Research completed: January 2025

DOI: http://dx.doi.org/10.7488/era/5650

Executive summary

Background

The planning system in Scotland is used to make decisions about future developments and use of land in towns, cities and countryside. Planning authorities are required to prepare evidence reports as part of the local development plan (LDP) process. These provide a summary of the baseline data used and explain the implications of the LDP.

Supported by National Planning Framework 4 (NPF4), planning LDPs should account for and address current and future climate risks, and enable places to adapt accordingly. Accurate, sub-national spatial data, which identifies geographic features such as rivers and utilities, is vital to create effective plans with a sound evidence base to evaluate climate risks. Fully evidencing climate risk requires an understanding of hazards, but also exposure and vulnerability, typically requiring interpretation of multiple datasets at once.

This report explores the geospatial resources that are available to support the evidence gathering stage with a view to improving access to geospatial data on climate risk. It identifies existing data, data gaps, barriers, and resources needed for evidence-based planning and delivery.

Key findings

Through engagement with a selection of Scottish Planning Authorities, we found:

Data for evidence reports

  • A wide range of data is required to assess climate vulnerabilities and impacts, some of which require substantial climate and data expertise to interpret.
  • Most required data is free for planning authorities.
  • Planning authorities tend to rely on datasets familiar to them – such as Flood Maps (SEPA), Dynamic Coast, Scottish Index of Multiple Deprivation (SIMD), and OS MasterMap to assess climate risks like flooding, coastal erosion, and social vulnerability. These datasets are highly usable, with consistent coverage and quality across Scotland, but sometimes require geospatial expertise for analysis.
  • There are additional datasets and tools which would benefit from further adoption by Planning Authorities, especially the Local Authority Climate Service. Additional datasets related to wildfire risk, air quality and land use may offer value, but would require some transformation, processing and interpretation to the climate context.
  • Significant data gaps exist for urban heat islands, storm damage, health, water, infrastructure and landslides. Proxies (e.g. combining urban form, green space, and housing quality data) are suggested for urban heat island assessments. However, these must be approached in a considered way, which balances the potential effort to develop the interpretation against the likely risk.

Planning authorities’ approach

  • There is a knowledge gap on how climate risk impacts planning. Some planning authorities have limited prior experience on climate risk, fewer technical data skills within their teams and no dedicated climate change professional. This leads to planning authorities mainly focusing on flood risk, where they have more familiarity.
  • Planning authority use of spatial data is limited, despite support for it in the Local Development Planning Guidance. This underuse may result from limited awareness of the guidance and expectations of evidence reports, and a lack of capacity and skills to interpret geospatial data.
  • Planners expressed a wish for a simplified approach to incorporate climate adaptation considerations into their plans.
  • Planning authorities find it challenging and time-consuming to gather data from multiple providers.
  • There is value in carrying out Climate Risk and Vulnerability Assessments (CRVAs) to better direct the use of data but there is no consistent approach or simple tool available for planning authorities to use.
  • Collaboration across planning authorities allows knowledge and resources sharing, which leads to more consistent and effective outcomes.
  • Given the wide range of potential data and analysis, planning authorities benefit from instances where work had been undertaken ahead of the LDP process to provide a view of which risks are most impactful, allowing a more focused approach to data.

Briefing note for planning authorities

  • Many planning authorities lack clarity on which data should be used for assessing climate risks and vulnerabilities, and how to interpret it. We have created an accompanying briefing note (Section 9.5), which should help by providing guidance on more usable and interpretable data.

Glossary / Abbreviations table

ADMS

Atmospheric Dispersion Modelling System

BGS

British Geological Survey

CC BY

Creative Commons Attribution License (further detail in 9.1.2)

CLIMADA

CLIMate ADAptation, Economics of Climate Adaptation

CRVA

Climate Risk and Vulnerability Assessment

CCRA

Climate Change Risk Assessment

DSM

Digital Surface Model

DTM

Digital Terrain Mode

EFFIS

European Forest Fire Information System

GIS

Geographic Information System

HabMoS

Habitat Map of Scotland

LA

Local Authority

LACS

Local Authority Climate Service

LDP

Local Development Plan

LiDAR

Light Detection and Ranging

LPA

Local Planning Authority

LSOA

Lower Super Output Area

NGD

National Geographic Database

NPF4

National Planning Framework 4

OGL

Open Government Licence (further detail in 9.1.2)

OpenCLIM

Open Climate Impacts Modelling framework

OS

Ordnance Survey

SNAP3

(Third) Scottish National Adaptation Plan

SEPA

Scottish Environmental Protection Agency

SIMD

Scottish Index of Multiple Deprivation

Sniffer

Independent charity – knowledge brokers for a resilient Scotland

PSGA

Public Sector Geospatial Agreement (further detail in 9.1.2)

UHI

Urban Heat Island

UKCCRA3

(Third) UK Climate Change Risk Assessment

UKCP18

UK Climate Projections 2018

UK-CRI

UK Climate Risk Indicators

Context and approach

Context

The reduction of emissions and adaptation to current and future risks of climate change is a challenge which is vital to be addressed via the planning system. The planning system provides opportunities to adapt to both current and future risks of climate change, as well as the potential to promote nature recovery and restoration in the area.

As part of the effort to modernise and update the planning system, the Scottish Government aims to align land-use planning with an outcomes-based approach to deliver sustainable development. This approach supports the National Performance Framework National Outcomes (Scottish Government, 2015) and supports the United Nations Sustainable Development Goals (United Nations, 2015).

Development planning, which outlines how places should change and where development should and should not happen, requires planning authorities to prepare and publish a local development plan (LDP)[1], updating on a 5 yearly basis.

The National Planning Framework 4 (NPF4) (Scottish Government, 2023c),puts climate change adaptation and resilience front and centre. A clear understanding of the impact of hazards and risks related to climate is required for an effective plan, and this must be underpinned by the effective use of climate risk data.

Defining climate risk

In this report, we refer climate risk in line with existing climate literature. Risk is defined as a combination of hazard, exposure and vulnerability (IPCC 2014).

Hazards are physical events which may have adverse effects, such as sea level rise & increased heat.

Exposure indicates the presence of people, resources, infrastructure which could be impacted by the hazard, and the extent to which they can be reached by the hazard. Physical proximity is one key consideration in understanding degree of exposure.

Vulnerability indicates to which extent people, resources or infrastructure could be more or less impacted by a hazard

Crucially, data can indicate hazard, exposure, vulnerability, or potentially a combination of the factors if indicating risk. However, if a dataset was not designed with the above in mind, it would need to be reinterpreted to a climate risk context. As an example, Ordnance Survey provides extensive data on the location of buildings, infrastructure and natural features, but geospatial analysis would be required to derive metrics such location to flood zones to indicate risk of flooding.

There is a substantial range of potential hazards associated with climate change in Scotland (Grace et. Al 2025). For this report, our engagement with the planning authorities focussed on the applicability of data, therefore a simplified grouping of hazards and risks was used (Table 1). In instances where datasets were particularly applicable to vulnerability and exposure, this is discussed in detail in Section 4.

Table 1 – Hazards and risks, as summarised in this report

Hazard Groups

Rainfall & Storms

Temperature & Water Scarcity

Sea Level Rise

Well Represented Hazards and Risks

Flooding

Costal Erosion

Health risks

Air pollution

Loss of land

Flood risk

Potentially Under Represented Hazards and Risks

Storm damage

Landslides

Water pollution

Agricultural changes

Habitat changes

Urban Heat Islands

Habitat Loss

Infrastructure damage

Local development plan evidence reports

Evidence reports are an early, statutory step in the development of a local plan. It provides a summary of the baseline data and other information which will form the basis of the plan.

This research focuses on the evidence gathering stage for climate risk – specifically, the tasks of early engagement and data collection, preparation of the evidence reports and a gate check by the Planning and Environmental Appeals Division (DPEA).

Evidence reports should be proportionate, with planning authorities having the discretion to tailor them to local characteristics and conditions. The Local Development Planning Guidance (Scottish Government, 2023b) provides guidance to support planning authorities in preparing evidence reports, including potential datasets relevant to NPF4 policies for climate change adaptation planning.

In addition to data access, there is a need to draw out implications of the data for the plan. It is not just about accessing the geospatial climate risk dataset but also ensuring its usability to accurately inform local development plans.

Rationale for this research

The lack of easily accessible spatial data on climate risk at a sub-national resolution has been identified as a key barrier to localised understanding of climate change adaptation by local authority planning officers.

Data gaps and accessibility issues create barriers to planning authorities producing proportionate, evidence-based plans. The aim of this research is to establish options for improved, simplified access by Scottish planning authorities to geospatial data that enables consistent, collaborative climate adaptation in local planning.

The intended audience for this research includes the Scottish Government and planning authorities. The work was commissioned on behalf of the Scottish Government, with particular interest for colleagues from the Climate Change Division and Planning, Architecture and Regeneration Directorate. A standalone briefing note and data catalogue (see Section 9.5) has also been produced specifically for planning authorities to showcase the available datasets.

Research methodology

The research involved an evidence review including a review of relevant literature, planning requirements and an in-depth data analysis of available risk data and its characteristics. Stakeholder engagement was conducted with planning authorities which were at various stages of evidence report development (see Figure 1) from early planning to successful completion. The engagement included interviews, as well as a wider workshop (See 9.3). Findings from these activities were the analysed to understand current needs, challenges and possible solutions to improve the process.

A map of Scotland, highlighting local authorities who were involved in the study. The LAs highlighted are the Western Isles, Moray, West Dumbarton, Glasglow City, the Lothians, the Borders and Fife

Figure 1 – Planning authorities engaged with in this study included Western Isles, Moray, West Dumbarton, Glasgow City, the Lothians, the Borders and Fife

 

Climate risk data

Effective data is central to the local development plan, and it is key that the right data is used and referenced for the evidence report. Additionally, the evidence report is expected to rely on spatial data, for which baseline evidence sources should be accessible.

There is a large range of data potentially available for use in evidence reports. This section provides a consolidated assessment of key datasets.

Our engagement with planning authorities identified:

  • Five climate-related datasets that were familiar to planning authorities and were – or were intended to be – used to produce the evidence report.
  • Eight datasets which would be valuable if used more extensively by planning authorities in the preparation of evidence reports.
  • Five areas of concern to planning authorities in relation to the evidence report which did not have a dataset available, or a clear methodology, documented below as data gaps.

In this section, key aspects of the data are provided, such as name, the organisation providing the data. The data license under which the data is made available is provided, the full implications of the license to usage by planning authorities is detailed in Section 9.1.2.

The majority of datasets reviewed are updated and published at a rate sufficient for their purpose, though we have noted instances where there may not be a clear long term plan for the maintenance of the data.

Several other datasets were identified as having potential value. For the full list of all data sources reviewed please see the accompanying data catalogue (Section 9.5)., which catalogue includes details of the metadata and access links.

Key datasets already in use

Through the interviews and workshop, there were multiple datasets already in use by planning authorities in the production of the evidence reports, though not consistently in all cases. The most popular datasets are discussed in this section, along with a narrative of how the datasets were applied and if any issues were faced.

Table 4.1 – Key datasets already in use by planning authorities

Section

Dataset name

Provider

License[2]

Hazard Applicability[3]

Usability[4]

4.1.1

Flood Maps

SEPA

OGL

Rainfall, Storms, Sea Level rise

High

4.1.2

Dynamic Coast

NatureScot

OGL and PGSA

Rainfall, Storms, Sea Level rise

High

4.1.3

Scottish Index of Multiple Deprivation

Scottish Government

OGL

All hazards/ vulnerability

High

4.1.4

OS MasterMap

Ordnance Survey

OGL/ PSGA

All hazards

Medium

4.1.5

Light Detection and Ranging (LiDAR)

Scottish Government

OGL

All hazards

Low

Flood Maps

Provider

License

Hazard Applicability

Usability

SEPA

OGL

Rainfall, Storms, Sea Level rise

High

The consensus among most participants was that the Flood Maps from the Scottish Environment Protection Agency (SEPA) were a useful source for assessing increased flooding risks, which could be an outcome of both increased magnitude and frequency of rainfall, storms and sea level rise. The SEPA data is presented using a simple index (high, medium and low risk) down to ‘street’ level, which lends to easy interpretation by all stakeholders. The SEPA data also distinguishes between current flood risk, and future flood risk up to the 2080s, in the ‘Future Flood Maps’ layer. One participant also commented that the support provided by SEPA is also incredibly useful. Given the flood data also overlaps with other planning use cases out with the evidence report, there is a lot of familiarity with the data.

Dynamic Coast

Provider

License

Hazard Applicability

Usability

NatureScot

OGL and PGSA

Rainfall, Storms, Sea Level rise

High

Data from Dynamic Coast is used by multiple planning authorities. This project undertook a wide range of analyses, from coastal change due to sea level rise to the social disadvantage of the population exposed to coastal erosion. The output is a series of datasets on coastal erosion, intended as a broad planning tool for ‘street’ to ‘regional scale’ mitigation. The data also includes social vulnerability as an indicator. For coastal planning authorities, the data was seen as valuable and usable, though may not be as accurate or applicable in estuarine areas. The outputs include a mixture of OGL and PSGA data, so while most of the data is fully open, not all layers can be supplied to all stakeholders.

Scottish Index of Multiple Deprivation

Provider

License

Hazard Applicability

Usability

Scottish Government

OGL

All hazards/ vulnerability

High

The Scottish Index of Multiple Deprivation (SIMD) dataset provides a range of indices which can be used to highlight areas of high deprivation that may face a higher impact from climate risks. The data is presented at Lower Layer Super Output Area (LSOA) level (e.g. ‘neighbourhood’ level) and summarises social issues in simple to interpret indices. The housing index specifically accounts for houses which are overcrowded, and those which do not have central heating – key factors to consider when assessing risks related to several climate hazards.

OS MasterMap

Provider

License

Hazard Applicability

Usability

Ordnance Survey

OGL/ PSGA

All hazards

Medium

There is a large range of data available from the Ordnance Survey (OS), which can cover a range of topics from housing, infrastructure to green space and biodiversity. OS also provides products which can be used as backdrop maps to improve the accessibility of data when shared with stakeholders. The OS MasterMap range of datasets has been used in local government for various purposes since its launch in 2001, so there is likely to be organisational familiarity, especially in GIS teams. OS has been in the process of refreshing its key products with the introduction of the National Geographic Database (NGD). This is intended to add additional data to OS’s products to serve further analytical use cases and adds data such as the presence of green roofs and solar panels on buildings (coming in future release), habitat classifications and building ages. OS data is largely licensed under PSGA or OGL, and access is provided via the OS Datahub. OS also has products which identify areas of greenspace, namely MasterMap Greenspace and OS Open Greenspace. OS data is all high resolution, ‘street’ level data.

OS data is of high quality and coverage, providing street level data across Great Britain, which is updated frequently. Indicators for climate hazards, however would need to be derived through analysis. This would generally require geospatial skills and tools, but additionally, OS datasets tend to be large and complex. OS has made some efforts to address the complexity of accessing large data, including ‘Select+Build’ features, and API access. All planning authorities, as PSGA members, can access direct technical support from OS.

Light Detection and Ranging (LiDAR)

Provider

License

Hazard Applicability

Usability

Scottish Government

OGL

All hazards

Low

LiDAR data from the Scottish Remote Sensing portal is valuable for assessing risks related to flooding. Digital Surface Model (DSM)/Digital Terrain Model (DTM) data from LiDAR can be easily interpreted and integrated with other steps in the analysis. The Scottish Remote Sensing portal has OGL licensed LiDAR data in a relatively easily accessible form – however, the coverage of the data is mostly focussed on the Central Belt, limiting the ability for some planning authorities to use. Additional coverage for the data was announced as part of the Future Farming Investment Scheme[5], which should improve the usability of this data in the future. The data is high resolution, supporting analysis at ‘street’ level.

Suggested datasets for future wider use

The following datasets were discussed in interviews and workshops, but we found that not all planning authorities sampled were using them. For some datasets, the low uptake by planning authorities was due to difficulty in the use, or accessing of the dataset, whereas for others low uptake was down to a lack of familiarity.

In this section we have provided a narrative for these datasets to indicate where they may be of value for planning authorities to use going forward.

Table 4.2 – Suggested datasets which could be used by Planning authorities for further value

Section

Dataset name

Provider

License[6]

Hazard Applicability[7]

Usability[8]

4.2.1

Local Authority Climate Service

Met Office

OGL

All hazards

High

4.2.2

Habitat Map of Scotland

NatureScot

OGL

All hazards

Medium

4.2.3

European Local Climate Zones

Demuzere et. al. (2022)

CC BY 4.0

All hazards

High

4.2.4

UK Climate Risk Indicators (UK-CRI)

UK Climate Resilience Programme

CC BY 4.0

All hazards

High

4.2.5

River Basin Management Plans

SEPA

OGL

All hazards

Medium

4.2.6

Neighbourhood Flood Vulnerability Index (NFVI) and Social Flood Risk Index (SFRI)

Climate Just

OGL

Rainfall & Storms

High

4.2.7

UK Climate Projections 2018 (UKCP18)

Met Office

OGL

All Hazards

Low

4.2.8

GeoSure, GeoCoast and GeoClimate

British Geological Survey

OGL and Licensed

Rainfall & storms, sea level rise

Low

Local Authority Climate Service

Provider

License

Hazard Applicability

Usability

Met Office

OGL

All hazards

High

The newly launched Local Authority Climate Service (LACS) from the Met Office aims to provide planning authorities across the UK with crucial information on climate change to support decision-making. The LACS provides a simple interface for analysing changes related to key hazards and includes climate averages and climate indicators. A Climate Report can be generated through the Climate Explorer. Planning authorities can add data and then use it in other applications such as Excel and Power BI. It is built using geospatial technology from Esri UK and is part of the Climate Data Portal (Met Office, 2024b) which hosts the information within the Local Authority Climate Projections Explorer. The LACS also includes guidance on the process of assessing climate risk with ‘regional’ level data. The Met Office launched the new beta service on 9 October, so as a new service has not yet seen widespread adoption in planning authorities. The Met Office are inviting feedback to help drive improvements of the LACS – the conclusions of which could be used as the basis to feed into this improvement process. Additionally, it could increase the number of Scottish planning authorities involved, increasing their awareness and knowledge of the system, and also make sure the LACS delivers the service that Scottish planners need. The LACS is not currently configured to provide reports for National Park planning authorities, but does cover all Scottish local authorities.

Habitat Map of Scotland

Provider

License

Hazard Applicability

Usability

NatureScot

OGL

All hazards

Medium

The Habitat Map of Scotland (HabMoS) is a composite dataset including different layers of detailed habitat data. All have been given a common Habitat Coding from the European Nature Information System (EUNIS). Using this data, a mapping of the existing habitats in a planning authority can be created. High value, or at risk habitats can then be identified, and habitat loss due to hazards such as sea level rise can be accounted for . The data is OGL licensed, with ‘street’ level resolution. HabMoS brings together habitat and land use data from multiple sources into one map, but the data is not interpreted in the context of climate hazards, so further interpretation and combination with additional datasets would be required to draw conclusions.

European Local Climate Zones

Provider

License

Hazard Applicability

Usability

Demuzere et. al. (2022)

CC BY 4.0

All hazards

High

The European Local Climate Zone (LCZ) data creates a simple typology for the built environment and landcover which is intended to support decision-making around climate risks. The data aims to characterise the urban landscape into broad categories (such as low-rise and high-rise housing) so that interactions between urban form and risks such as poor air quality, flooding and heatwaves can be modelled. Data is provided at ‘neighbourhood’ level resolution. One workshop participant reported that they had undertaken a ground truthing exercise in their local authority and confirmed that the data was broadly valid. As the data was recently, in 2022 and was aimed at the climate academic community, this dataset has not yet found widespread use in planning authorities. There are not currently any regular updates or revisions published for the LCZ data. Given the data is at ‘neighbourhood’ resolution, there is less need for it to be updated frequently, as only large changes to the urban landscape would be detected. As well as the detailed methodology being public, an LCZ Generator tool is provided by Ruhr University Bochum[9] which provides potential opportunities for updated datasets to be created for Scotland in the future.

UK Climate Risk Indicators (UK-CRI)

Provider

License

Hazard Applicability

Usability

UK Climate Resilience Programme

CC BY 4.0

All hazards

High

UK-CRI data simplifies analysis of many risks into indices. For temperature related risks, the data includes an estimation of days (or events) per year of events including heat waves, amber heat-health alerts, tropical nights (nights with a minimum temp of 20 °C). This extends to heat related impacts on infrastructure, such as road melting and high temperatures on rail. The impact of hazards on agriculture such as growing season and heat stress are also reported. Rather than creating new climate data, the UK-CRI is an interface on existing datasets (primarily Met Office) which simplifies complex data into more easily interpreted indices. The Met Office publishes annual updates to its climate data, though the UK-CRI tool does not receive updates as frequently. At ‘regional’ scale, it is less critical that the data is frequently updated, though after 5-10 years if the tool does not receive data updates, it may become far less appropriate to use.

River Basin Management Plans

Provider

License

Hazard Applicability

Usability

SEPA

OGL

All hazards

Medium

River basin management plans set out actions to address current issues affecting water quality, water resources and fish. The management plans can be used in context with other data sources to understand risks which impact river health. River basin management plans are not explicitly geospatial datasets but relate to river basins which can be represented geospatially. The issues faced using this data mainly lie in the river basin boundaries not aligning with local authority boundaries, so requires some analysis. In addition, the key use case of the dataset is not climate risk or hazard related, so will require reinterpreting to the climate context.

Neighbourhood Flood Vulnerability Index (NFVI) and Social Flood Risk Index (SFRI)

Provider

License

Hazard Applicability

Usability

Climate Just

OGL

Rainfall & Storms

High

A national flood vulnerability dataset was created by the Joseph Rowntree Foundation and is publicly available via the ClimateJust Maps tool. This dataset provides and easily to use, ready-made index describing flood vulnerability by combing physical flood risk with several factors which represent socio-economic vulnerability to flooding. However, it is based on ‘street level’ data published in 2011, which at this scale becomes quickly outdated. England and Wales had their index updated in 2022. An updated Scottish equivalent would be a useful tool for planning authorities to explore the vulnerability to this specific and pressing hazard.

UK Climate Projections 2018 (UKCP18)

Provider

License

Hazard Applicability

Usability

Met Office

OGL

All Hazards

Low

The Met Office is the authoritative source for key climate projection data for the UK. UKCP18 products are commonly used for temperature and precipitation projections, but it can also provide data on humidity, wind and sea level rise. The climate projections generally support analysis at a ‘neighbourhood’ to ‘regional’ level, dependent on the specific data UKCP18 product.

The Met Office provides a UKCP18 User Interface for querying and extracting the data, graphs and pre-paired maps (plus access to the full data catalogue for those experienced in handling large datasets), but this does require some expertise in the underlying data to navigate, limiting its usability to planning authorities that have GIS teams or capability. This was reflected in the workshops, as some participants expressed concern that the climate data accessed from the UKCP18 portal was sometimes difficult to use. In addition, there is further interpretation work required to convert a numerical value from the data into a clear indicator which can be used to influence a decision. This interpretation of the climate data and translation into implications for the LDP was also found challenging , with some planning authorities being unable to fully explore what the data means for their plan.

The UKCP18 data is a crucial underpinning to climate analysis and has been used by some planning authorities. More recently the data has been made more usable with a set of pre-prepared indicators by tools such as the Met Office Local Authority Climate Service (where GIS users can also visualise the mapped data and also add their own geospatial data), and UK Climate Risk Indicators.

GeoSure, GeoCoast and GeoClimate

Provider

License

Hazard Applicability

Usability

British Geological Survey (BGS)

OGL and Licensed

Rainfall & storms, sea level rise

Low

Participants expressed an interest in data from the British Geological Survey, which has the potential to address risks such as coastal erosion and landslides. The BGS GeoSure, GeoCoast and GeoClimate datasets indicate risks arising from multiple hazards, with a range of open and licensed datasets. The use of BGS data was not widespread among participants, partly due to the licensing cost associated with the premium datasets.

There may be more value to be gained from these datasets, but it would likely require the supporting geotechnical knowledge and interpretation, unless a simpler way of indicating future risks is provided.

Perceived gaps and ways to address gaps

When discussing risks, participants expressed several areas where they felt there was insufficient data available to meet their needs. This was due more to the limited understanding of what data was required to support the analysis, rather than specific datasets lacking appropriate spatial and temporal resolution or having gaps in coverage.

It should also be considered that if these data gaps were closed, what value would they provide to the evidence reports in each planning authority, and to what extent would the planning process be able to take useful action on the data. Urban heat islands serve as a useful example – while it would be possible to carry out a detailed analysis in each planning authority, for rural, or northerly authorities, the risk could be understood to be minimal by using an understanding of the local context and long term heat risk from tools like the Local Authority Climate Data Service (see 4.2.1).

In this section, we list the key gaps and explore some datasets and approaches which could be used to address those gaps.

Urban heat islands

Participants generally expressed a lack of data to understand the risks associated with the urban heat island (UHI) effect. The overheating risk methodology can be derived from both UKCCRA3 (Built Environment chapter) and the previous Environmental Audit Committee evidence reviews (e.g. 2018). Determining the extent of the effect of UHIs in urban areas can be done using a temperature sensor network (at high spatial resolution), modelling (e.g. using dedicated products such as Envi-MET, adapting more commonly used modelling approaches, e.g. atmospheric dispersion modelling systems (ADMS) (Zhong et al., 2024), or analysis of high-resolution satellite data products. However, these approaches may not be suitable for all planning authorities due to resource or lack of specialist knowledge. Overheating risk is likely to be greater in areas where urban form is compact, where there is less green and open space, and where the housing quality is poor. As such, combining datasets on Local Climate Zones (to give urban form), green space, and Scottish Index of Multiple Deprivation may act as a proxy for estimating urban heat island magnitude (e.g. Ferranti et al., 2023). Housing quality can also be indicated in further detail by Home Analytics data from the Energy Savings Trust which provides specific attributes on building fabric. This is a simpler approach using GIS datasets that planning authorities may be able to use for their evidence reports.

Storm and wind damage

While there are multiple datasets for inundation and coastal erosion, we did not find much work done to understand wind damage to buildings, or from trees. Tree fall risk is a statutory responsibility so it may be that planning authorities have some of this data held within parks or urban forestry teams. There are datasets which use remote sensing techniques to identify trees. One such dataset is National Tree Map from BlueSky – however, as this is a proprietary, licensed dataset it is unclear if the cost of this dataset outweighs the value which can be gained.

Landslides

While participants did discuss landslide risk, there was no broad consensus on the approach, nor most appropriate data. The open data published by the BGS could serve as a potential baseline assessment of current risk which, if found to be sufficiently high, further research could be carried out incorporating premium data, or input from specialists.

Health infrastructure

Data on the locations of key health infrastructure are available from NHS Scotland and accessible via the Spatial Hub. However, the use of these datasets in the context of the evidence reports would require further interpretation in order to drive decision making in the climate context. Whilst it would be possible to interpret which areas could be exposed to hazards such flooding and coastal erosion, understanding the magnitude of the risk on health infrastructure from hazards such as heating would require additional data to determine vulnerability such as building age and fabric. In the workshops, these aspects were not raised by participants, suggesting that this has not been a focus for planning authorities thus far.

Water infrastructure

Relevant data on water infrastructure, from Scottish Water for example, for the climate context is either available piecemeal, or not published. To understand which data would be required, planning authorities would need more knowledge as to which risks are likely to require water infrastructure data to assess.

Further observations

Wildfire risk was one aspect investigated by some planning authorities. Seasonal risk forecasts, as well as real-time monitoring is published by the European Forest Fire Information System[10] (EFFIS). This is a valuable resource for assessing the current risk landscape for fires, but additional context would be required for evaluating future risk (see UK-CRI in Section 4.3 above).

Datasets such as the Scottish Air Quality Database[11] provide information on air quality monitoring, analysis and interpretation of data, and pollutant trends at national and local levels. Historical data can also be accessed via the Met Office. Since these are observational datasets, they can be used for assessing current risk, but additional context would be required for evaluating future risk.

For more rural or agricultural planning authorities, there was also value in land use and land cover data from NatureScot, which allows risk to peatlands and croplands to be assessed. For coastal areas this data could also be analysed alongside Dynamic Coast data.

Based on the interviews and workshop discussions, participants expressed several areas where they had difficulty using data for specific outcomes or were not sure what to use.

Most of the datasets which were found to be of value for the evidence report were not hosted by a single source such as the Improvement Service Spatial Hub. The overhead effort of data acquisition for the planning authorities could be improved by more of the data providers providing a copy of their data to the Spatial Hub. However, this approach would not be straightforward with all datasets, such as those which are licensed (e.g. BGS), or those were the provider includes an analytical interface for extracting key indicators (Met Office LACS or UK-CRI).

Analytical tools

We reviewed several different analytical tools, such as CLIMADA[12] and OpenCLIM[13] which are designed to support users in analysing climate datasets and produce new data outputs indicating risk. These tools are open source, adaptable and suitable for academic use cases. In our interviews and workshops, we did not receive any feedback from planning authorities on these tools, suggesting they do not use them. As they require a high degree of specific technical proficiency (e.g. running python code), they may not be particularly suited to the planning authority teams who are producing evidence reports.

Current Approach

Climate Risk and Vulnerability Assessments

Climate Risk and Vulnerability Assessments (CRVAs) or Climate Change Risk Assessments (CCRAs) are available for some planning authorities and some regions of Scotland. These include the Clyde area, and one in preparation for south east Scotland.

Nationally, there is the UK CCRA Independent Assessment (Climate Change Committee, 2021a) and the National Summary for Scotland (Sniffer, 2021). These documents are long, difficult to navigate, and have a comprehensive list of wide-ranging risks. For anyone with limited familiarity with climate science and/or individual sectors, it is hard to understand which risks are most relevant to their planning authority or which risks are most important to planning. Risks in these documents are categorised with urgency and magnitude scores, and there is no scoring of impact or likelihood (apart from flooding likelihood) at a national, regional or local scale. Planning authorities need this information for their evidence report requirements, but it is not provided in the national CCRA3.

National documentation on adaptation (i.e. Scottish Climate Change Adaptation Programme: progress report 2023 to 2024) does not directly relate to local planning process and/or is difficult for the untrained person to see the links. The wider list of literature reviewed is given in Section 9.4.1.

Local climate risk assessment barriers and challenges – findings from the academic literature

Research related to mapping climate risk has increased rapidly in recent years. Studies are usually area- and problem-specific, which means that there is no standardised approach. Some maps focus on the local level, such as a city scale, but some have also looked nationally. Some also consider both spatial scales. Similarly, maps that assess climate risk can vary in perspective, such as focusing on one climate hazard because it disproportionately affects the study area the map is produced for. While many do take a multi-hazard approach, some focus on specific challenges such as heat, flooding, and drought.

Methodological process can also vary greatly across such assessments which may affect results so, for decision-makers, it can be challenging to decide which method is most appropriate to use. One key feature of many CRVA maps is the weighting of variables, which affects the extent of which specific variables may influence overall scoring. The SIMD dataset from the Scottish Government, as an example, weights income and employment indicators more heavily than housing in its determination of the deprivation index. However, in a climate risk context, a different weighting may be more appropriate. From a local perspective, weighting variables may be beneficial as they can provide more accurate results for decision-makers. However, in some cases it is difficult to achieve and an unweighted approach is preferred. Reasons can include

  • a lack of data or local studies
  • the risk of politicisation that may underpin the decisions upon weighting which links to subjectivity and
  • complexities around how different climate hazards may weight other variables differently.

Ultimately, adaptation to climate change should be a process that is iterative and embedded into organisational practices. Knowledge underpinning decisions may be imperfect, incomplete, or comprise other challenges such as those outlined above. It is important nevertheless that the process is started with the best knowledge and data available at the time. In repeating the process, more experience is gained, and the challenges can begin to be addressed (Greenham et al., 2024b).

Approach to the evidence report

Current position

In both the interviews and workshop, the planning authorities were at different stages of preparing their evidence reports. This ranged from those at very early stages of preparation through to authorities who have drafted their evidence report and received feedback from the Gate Check[14]. It is important to note that the small number of authorities having received the Gate Check at the point of the interviews and workshop, meaning a small sample may have impacted some of the feedback, alongside the relatively small sample of planning authorities that could be engaged during this short project.

The participants’ attitudes towards producing the evidence report were slightly more positive than their understanding of climate risks in general, with a generally positive sentiment (Figure 2)

Two bar graphs showing how participants in the workshop felt regarding their understanding of climate risks in general and how they felt about producing evidence reports with climate risks considered. The top bar graph in orange showing understanding of climate risk indicates respondents ranged from indifferent to happy and the bottom bar graph in teal shows respondents were slightly more positive regarding incorporating climate risk in evidence reports.

Figure 2 – Sentiment captured during the workshop from the participants

Different approaches

The approaches used by planning authorities varied significantly, with different methods to identify data including policy review, evidence audits and workshops.

The teams undertaking evidence reports ranged in number of staff from 1-2 to 4-5 people. The use of specialist data or climate specialist colleagues in other departments within the planning authorities varied.

There appears to be a disparity on the anticipated timescales and resources required to undertake the evidence report. This depends on the extent to which planning authorities have already undertaken a climate change risk or vulnerability assessment and could be more reflective of local authority capabilities to conduct and deliver the output.

Some authorities have access to pre-prepared local or regional climate risk assessments or are part of existing climate ready projects (see Section 5.6). Others have access to climate change profiles, which provided an overview of expected future climate change. We also found some authorities had not explored climate risk and therefore had little existing evidence or experience to work from.

However, it was noted that even those planning authorities which had undertaken previous assessments found it difficult to access primary data. They were mainly using the conclusions of the past risk assessments to inform their evidence reports.

The implications of interpreting the data in a climate context and what the evidence actual means for informing or changing the local development plans was not always clear.

Using data to produce the reports

Concerns were raised by participants over the dynamic nature of the data, new data being published, and old data being updated. Not only did this make it hard to identify the latest datasets, but it also gave rise to concerns about evidence becoming out of date soon after reports were developed[15].

Concerns were also raised about the complex array of caveats and limitations that are inherent in much of the data. This included concerns about their own understanding and interpretation, and how these limitations should be portrayed in the reports in a non-technical manner.

Another issue raised was an inability to find locally specific data at a sub-local authority resolution; one local authority wanted to take a ‘neighbourhood’-level approach but felt that data did not exist to support this.

Data accessibility challenges

Challenges in accessing and fully utilising data exist at several points, and in ways which varied across planning authorities.

Firstly, a very broad set of potential datasets which could be used exists. The planning authorities had to locate many different data sources to compile the data they needed.

Next, the data needed to be downloaded and formatted from the different data sources and while most of the data required is licensable freely to planning authorities, we found a subset where the licensing implications and restrictions were unclear. In the case where the work was being carried out by organisations external to the planning authorities (e.g. Sniffer), additional barriers were faced as access to PSGA licensed data is not immediately granted, and additional contractor licenses need to be provided. PSGA contractor licenses are free, and they limit the scope of external use of the data to specifically the contracted work.

Once the data is obtained, its application to understanding climate risks and hazards is not always straightforward. Some information is in a readily usable format, while others require expert input before analysis is possible. In the case of datasets such as Dynamic Coast, or data presented via the Met Office Local Authority Climate Service, data is pre-transformed and interpreted in a climate context. As an example, the Met Office LACS provides simple indices such as “Average Number of Extreme Summer Days”. This contrasts with datasets such as UKCP18, where a user will need to download the dataset, isolate the area of interest, extract the climate values, and determine what metric to rate them against. This is a time-consuming process, requiring both geospatial and climate expertise.

Understanding how to link the data back to the guidance and the requirements of the evidence report is a key required outcome, and the extent to which accessing this insight from the data can be achieved varies widely across the datasets used.

Understanding climate risks

Concerns were expressed in the workshop by participants from smaller planning and development teams about resourcing, where there was little or no dedicated resource within the team, or even access to a dedicated individual with climate change knowledge. This makes the process more difficult and time consuming for these planning authorities.

Risks vary from area to area, but additionally will vary over time as the climate changes. We found that many workshop participants were focused on a current view of risk, rather than being informed on how risks might change based on future projections. Risks across different hazard areas discussed, and whether they seemed well represented or potentially underrepresented in the workshops are outlined in Table 1. Additionally, not all planning authorities had fully defined which hazards were most appropriate for their region.

Given many planning authorities already have a track record in modelling flood risk, and have a greater understanding of flood risks specifically, there is a heavy focus on flooding. There is less awareness of other climate risks, specifically future climate risks, and how they may relate to development planning. In some cases, there is confusion between climate mitigation (through reduction of greenhouse gas emissions) and adaption to reduce climate risk.

The value of pre-existing work

In some instances, planning authorities were (or will be) able to build upon pre-existing work. Of particular value is work focused on climate risk, and the production of data layers specifically to allow easy interpretation from a wide range of users.

The data and findings from examples like Climate Ready Clyde and Climate Ready South East Scotland can be re-used and built upon for consistency, as well as reducing the effort required for an evidence report specifically. However, planning authorities who have not benefited from these will be at a relative disadvantage.

Climate Ready Clyde

A screenshot from the Glasgow City Region Climate Vulnerability webmap showing the Glasgow City Region. Data layers shown include local authority boundaries, postcodes affected by flooding and postcodes affected by heat. Climate Ready Clyde (CRC)[16] is a leading cross-sector initiative funded by 12 member organisations and supported by Scottish Government to create and deliver a shared vision, strategy and action plan for an adapting Glasgow City Region. CRC have produced Glasgow City Region’s Adaptation Strategy and Action Plan (Sniffer, 2024a) which includes a webmap (created by Clydeplan) that shows the location of postcodes most vulnerable to the impacts of climate change (Clydeplan, 2022). This includes heat risk (derived from the 4EI Heat Hazard Index[17]) and a layer highlighting postcodes within the top two heat risk bands. The work from CRC on the Climate Risk and Opportunity Assessment and data layers in the vulnerability map directly informed Glasgow City Council’s Evidence report.

Figure 3 – Glasgow City Region Climate Vulnerability Map

Climate Ready South East Scotland

A new project to support collaborative climate action in the Edinburgh and south east Scotland City Region. Climate Ready South East Scotland[18] is led by Sniffer, working in partnership with the region’s six local authorities: City of Edinburgh, East Lothian, Fife, Midlothian, Scottish Borders and West Lothian.

Climate Ready South East Scotland plans to:

  • Identify and prioritise the risks and opportunities from climate change to Edinburgh and south east Scotland’s society, economy and environment between now and 2080.
  • Lay the foundation for a transformational approach to climate adaptation and resilience for the city region.
  • Support a just transition to a net zero and climate resilient economy, in a way that delivers fairness and tackles inequality and injustice.

A detailed assessment of the climate risks and opportunities faced by the Edinburgh and south east Scotland City Region will be carried out, and is intended to be published by March 2025. This assessment will both draw on the best available scientific evidence, and work with communities across the region to gather and share their experiences of climate change. It will inform decision-making across the region, laying the foundation for collaborative climate adaptation action (Sniffer, 2024b).

Overall observations planning authorities’ approaches

We collated six overall observations, looking across the literature review, interviews and workshop.

A focus on flooding and a lack of awareness of available non-flood data

Knowledge and understanding of flood risk and applicable datasets is much more established with planning authorities. While this experience is valuable, it does lead to a focus on flooding to the detriment of the consideration of other risks.

In general, the participants revealed a lack of awareness around climate change projection data, including where to source it and how to use it. As an example, whilst some participants with backgrounds and expertise in climate had knowledge of the data, planners in general were far less familiar with UKCP18 data, when asked about data they used. Most questions on data were directed back to flood information. In one interview, when questioned more on UKCP18 there appeared to be no knowledge of where this data can be located and how to access it. Some statements suggested a lack of understanding of what climate projections are and different scenarios used, however this was not fully probed in the interviews. This data is key in understanding the risks that planning authorities will face in the future and the degree of potential impact.

Spatial data not always used

The use of spatial data appears limited even though the use of it in evidence reports is supported by the Local Development Planning Guidance (Scottish Government, 2023b). Whilst some spatial datasets are well known by planning authorities (e.g. SEPA flood maps) the use of further datasets is not extensive due to poor understanding of the geospatial data required and/or ability and access to staff with the right skills to use and interpret geospatial data.

Simple indices support interpretation

Interviewees generally favoured datasets which provide simple indices tailored to the climate risk context, such as SEPA flood maps and Dynamic Coast. These datasets allow interpretation by users without specific climate or data expertise. This contrasts with the UKCP18 data, as an example, which provides users with hazard data like temperature and rainfall values over time. Considerable interpretation would need to be done to translate this data into a measure of risk which can be interpreted. Users without climate or geospatial data experience can be supported in understanding the implications if the data is pre-prepared, and presented with relatively simple indicators.

Section 9.2 provides examples of tools and datasets which have been developed outwith Scotland, used to support users without climate expertise in understanding risks.

Simplification of the approach is needed

There is a need to simplify the approach that planners adopt, to enable them to incorporate climate adaptation into their plans. The evidence report is an important part of this process to help development of a baseline and support understanding of the climate risks faced by planning authorities now and in the future. To do this, a Climate Risk and Vulnerability Assessment (CRVA), which considers key hazard, vulnerability and exposure data, is a valuable prerequisite to identify those risks which can be mitigated by planning. Spatial data is key to undertaking an accurate and specific assessment, although there is currently no simple tool to support it. An example of this would be the methods and approach taken by the University of Birmingham for work done for one local authority (Birmingham) and one regional authority (West Midlands) in England (see Section 9.2). Aside from a tool, authorities would benefit from greater understanding of the key datasets which provide the best outcomes. This mirrors findings from the evidence report gate checks completed to date.

Prior work and climate data skills are advantageous

There was a general observation (which was also identified by several stakeholders) that some planning authorities faced greater challenges in the evidence report process. This is because they have little prior work on climate risk, less technical data skills within the team and no dedicated climate change professional within the Council.

Planning support and guidance is not specific on the application of data

The literature review illustrates that there is little information on climate risks and resilience that is written to support either local authority planners or the evidence report process. There is a wide range of data available, which could be used in many different approaches to be applied to understanding climate risk and appropriate adaptations. Furthermore, there is a gap in knowledge on how climate risk impacts planning and how planners can enhance climate resilience through planning requirements and the local development plan. Such information contextualised for Scottish planners would be invaluable to support the evidence report process and would allow adaptation to become business as usual within planning processes.

 

Conclusions

The following conclusions drawn from this research project to improve the evidence base for climate resilient planning policy are:

Accessibility and usability of data

  • There are numerous and varied datasets required to consider the range of vulnerabilities to, and impacts from, climate risks. There are several key datasets which are underutilised by planning authorities currently.
  • Many planning authorities do not have a clear and specific understanding of what data is needed to assess climate risk and vulnerabilities. The accompanying Briefing Note for Scottish Planning authorities to this research report (see Section 9.5) should provide support in providing signposted usable data.
  • Significant data gaps exist for urban heat islands, storm damage, health, water infrastructure and landslides. Proxies can be used, e.g. combining urban form, green space, and housing quality to assess urban heat island risk. However, consideration should be taken to ensure a consistent methodology, and a proportional amount of effort given potential risk.
  • The most useable and accessible data sources, such SEPA, Dynamic Coast, and Met Office LACS provide pre-determined, simple indices which provide a clear indication of climate risk. These allow planners to make clear decisions, without having to apply climate or data expertise to determine risk themselves.
  • Not all datasets provide simple indices, however, there are several datasets which could be used by planning authorities in the evidence reports which are not widely used currently. A consistent methodology for planners on how the indicators can be derived and used to incorporate adaptation and resilience into local planning would be advantageous.
  • Longer term, a single entry-point to these datasets would make this process easier for the planners and ensure that all Planning authorities have similar data to undertake the assessments
  • The data required is also mostly free for planning authorities, however, there are some licensing differences to be aware of when publishing to the public. See 9.1.2 – Data Licensing for further detail.
  • Accessibility could also be improved with further guidance on certain requirements mean and how they can be achieved. For example, the requirements ask planning authorities to assess the likelihood of risks occurring. This is a complex task, requiring knowledge of the climate hazards, how they will change, uncertainties, the ranges of climate outcomes depending on scenarios. Guidance on how to define likelihood and how to use data to evaluate likelihood is important, and can be paired with a specific indication of which dataset can be used for that purpose.

 

Understanding and capacity

  • Planning authorities find it time-consuming and difficult to get the required data from all the different providers.
  • Undertaking climate change risk assessments prior to the evidence report would provide a better understanding of which risks and hazards are most impactful.
  • However, planning authorities may need help doing this (especially the smaller planning authorities and/or those without climate and GIS and data experts), including:
  • Direct funding to outsource.
  • Support to identify partners and apply for funding.
  • Sharing or secondment of staff with climate resilience/climate science and GIS and data skills.
  • Collaboration and co-funding with neighbouring/regional planning authorities, like the ‘Climate Ready’ regional projects.
  • As an example, Sniffer is an independent charity that supports and coordinates the climate ready programmes in Scotland, including work such as webinars which discuss the use of different datasets. Sniffer currently hold a Scottish Government funded contract (Adaptation Scotland) to provide some capacity building support to planning authorities. This could be expanded to provide wider support for the climate change risk assessment process and support planners in translating the findings into the evidence report and the local development plans.
  • It should also be noted that the assessment of likelihood of risks occurring, beyond flood risk, is not undertaken in the UKCCRA3 or Scotland’s national summary.
  • It is useful to understand and address vulnerability at the evidence report stage, although stakeholders did not seem familiar with this as a concept or how it might be assessed.

Potential for action

Based on the findings from this research, the following actions could be explored in the short term to enhance and improve the coverage and usefulness of evidence reports:

  • Engage with the Met Office for a review of planner-specific user experience when accessing the latest UK Climate Projections (UKCP18)
  • The impression from most stakeholders was that UKCP18 projections are daunting and avoided by planners. The Met Office Local Authority Climate Service (LACS) (Met Office, 2024a) is still in beta, and feedback should be provided on how it could further meet the needs of Scottish planners.
  • Explore whether non-flood related climate data could be sourced directly via an existing data service for the creation of bespoke Climate Risk and Vulnerability Assessment indices and geospatial data portal relevant to planning in Scotland.
  • Explore the inclusion of features to support the National Park planning authorities in the LACS.
  • Engage with the British Geological Survey (BGS) to explore expansion of access for the assessment of landslide risk – and potential inclusion of licensed data.
  • Provide planners with further detail on which aspects of various datasets are valuable for their local plans, including the climate risks which planning should address (e.g. overheating, surface water flooding).
  • Encourage cross-authority engagement and collaboration. Given the inconsistent availability of knowledge, skills and capacity, peer learning and support can potentially provide a valuable approach to improving quality and consistency.
  • Share and promote the list of data (from this research) as a standalone resource, cross referenced with the relevant climate risks. See accompanying data catalogue (Section 9.5).
  • This research also clarifies which data licences may be required to support evidence report production, and further guidance on the impacts of the different license types.
  • Investigate funding options for regional Climate Risk and Vulnerability Assessments. As a first step, a CRVA provides a clear steer on what the key risks are, therefore allowing a more targeted approach to the Evidence reports.
  • Scope out the requirements for a Climate Risk and Vulnerability Assessment data platform for centralising the hosting of key datasets. In addition, this should include the development of new datasets and indicators which allow interpretation to non-climate, or non-geospatial users more easily. This could be delivered as a new tool or an extension to an existing one.

There is potential in the longer term to make the key national datasets available, with pre-interpreted indices available in one location. The data could have simple (e.g. high, medium, low) indices with user friendly guidance on what the data is, what it means and caveats (this could be 4-5 key hazards, with a climate vulnerability index). It could link directly to the datasets that have been identified in this report and could also potentially use some of the data from the analytics tools. This would require further research and dialogue with potential providers.

 

References

Birmingham City Council (2024) Climate Risk and Vulnerability Assessment map. Available online: https://maps.birmingham.gov.uk/webapps/CRVA/ [last accessed October 2024]

Clydeplan (2022) Glasgow City Region Climate Vulnerability Map. Available online: https://climatereadyclyde.org.uk/climate-vulnerability-map/ [last accessed October 2024]

Environmental Audit Committee (2018) Heatwaves: Adapting to Climate Change. UK Parliament Commons Select Committee. Environmental Audit. 2018. Available online: https://publications.parliament.uk/pa/cm201719/cmselect/cmenvaud/826/82604.htm [last accessed October 2024].

Ferranti, E., Cook, S., Greenham, S.V., Grayson, N., Futcher, J. and Salter, K., (2023) Incorporating Heat Vulnerability into Local Authority Decision Making: An Open Access Approach. Sustainability15(18), p.13501. https://doi.org/10.3390/su151813501

Grace, E., Marcinko, C., Paterson, C., & Stobbs, W. (2025). Using future climate scenarios to support today’s decision making. CXC/Government Actuary’s Department.

Greenham, SV., Jones, SA., Ferranti, EJS., Zhong, J., Acton, WJF., MacKenzie, AR., Grayson, N., (2023) Mapping climate risk and vulnerability with publicly available data. A guidance document produced by the WM-Air project, University of Birmingham. Available online: https://doi.org/10.25500/epapers.bham.00004259 [last accessed October 2024]

Greenham, S, Ferranti, E, Jones, S, Zhong, J, Grayson, N, Needle, S, Acton, J, MacKenzie, AR & Bloss, W. (2024a) An open access approach to mapping climate risk and vulnerability for decision-making: A case study of Birmingham, United Kingdom, Climate Services, vol. 36, 100521. https://doi.org/10.1016/j.cliser.2024.100521

Greenham, SV., Ferranti, EJS., Cork, NA., Jones, SA., Zhong, J., Haskins, B., Grayson, N., Needle, S., Acton, WJF., MacKenzie, AR., Bloss, WJ. (2024b). Mapping climate risk and vulnerability in the West Midlands. A guidance document produced by the WM-Air project, University of Birmingham. https://doi.org/10.25500/epapers.bham.00004371

IPCC (2014a). Summary for policymakers. In: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1-32. Available at https://www.ipcc.ch/report/ar5/wg2/.

Met Office (2024a) Local Authority Climate Service. Available online at: https://climatedataportal.metoffice.gov.uk/pages/lacs [last accessed September 2024]

Met Office (2024b) Met Office Climate Data Portal. Available online at: https://climatedataportal.metoffice.gov.uk/ [last accessed September 2024]

Scottish Government (2015) National Performance Framework National Outcomes. Available online at: https://nationalperformance.gov.scot/national-outcomes [last accessed October 2024].

Scottish Government (2019) Planning (Scotland) Act 2019. Available online at: https://www.legislation.gov.uk/asp/2019/13/contents/enacted [last accessed October 2024].

Scottish Government (2023a) The Town and Country Planning (Development Planning) (Scotland) Regulations 2023. Available online at: https://www.legislation.gov.uk/ukpga/1997/8/contents [last accessed October 2024].

Scottish Government (2023b) Local development planning Guidance, May 2023. Available online at: https://www.gov.scot/binaries/content/documents/govscot/publications/advice-and-guidance/2023/05/local-development-planning-guidance/documents/local-development-planning-guidance/local-development-planning-guidance/govscot%3Adocument/local-development-planning-guidance.pdf [last accessed September 2024].

Scottish Government (2023c) National Planning Framework 4 (NPF4). Available online at: https://www.gov.scot/publications/national-planning-framework-4/ [last accessed October 2024].

Scottish Government (2024a) Research to Inform National Planning Framework 4: Planning and Climate Change Guidance Report Issue 3. Available online at: https://www.gov.scot/publications/research-inform-national-planning-framework-4-planning-climate-change-guidance-report-issue-3/ [last accessed November 2024].

Scottish Government (2024b) Scottish National Adaptation Plan 2024 – 2029. Available online at: https://www.gov.scot/publications/scottish-national-adaptation-plan-2024-2029-2/ [last accessed November 2024].

Sniffer (2021) Third UK Climate Change Risk Assessment Technical Report: Summary for Scotland. Available online at: https://www.ukclimaterisk.org/wp-content/uploads/2021/06/CCRA-Evidence-Report-Scotland-Summary-Final-1.pdf [last accessed September 2024].

Sniffer (2024a) Climate Ready Clyde, Building a more resilient, prosperous and fairer Glasgow City Region. Available online: https://climatereadyclyde.org.uk/ [last accessed October 2024].

Sniffer (2024b) Climate Ready South East Scotland, Supporting regional climate action in the Edinburgh and South East Scotland City Region. Available online: https://climatereadyses.org.uk/about/ [last accessed October 2024]

UK Climate Change Committee (2021a) Independent Assessment of UK Climate Risk

Advice to Government For The UK’s Third Climate Change Risk Assessment (CCRA3), June 2021. Available online at: https://www.theccc.org.uk/wp-content/uploads/2021/07/Independent-Assessment-of-UK-Climate-Risk-Advice-to-Govt-for-CCRA3-CCC.pdf [last accessed September 2024].

United Nations (2015) The 2030 Agenda for Sustainable Development. Available online at: https://sdgs.un.org/2030agenda [last access October 2024].

WMCA (2022) West Midlands Levelling Up Growth Prospectus. Available at: https://www.wmca.org.uk/documents/levelling-up/west-midlands-levelling-up-prospectus/ [last accessed October 2024]

WMCA (2024) West Midlands Climate Risk and Vulnerability Assessment (WM-CRVA) Map. Available online: https://west-midlands-combined-authority.github.io/crva/ [last accessed October 2024]

Zhong, J, Lu, Y, Stocker, J, Hamilton, V & Johnson, K. (2024) Modelling the urban heat island in Birmingham, UK at the neighbourhood scale. In EGU General Assembly 2024., EGU24-19930, EGU General Assembly 2024, Vienna, Austria, 14/04/24. https://doi.org/10.5194/egusphere-egu24-19930

 

Appendices

Definition of Terms

Usability

Usability is summarised as follows:

  • High’ – a dataset which provides simple indices in a climate hazard and risk context and access and can be interpreted easily. Users will not need specific GIS or climate expertise to understand planning outcomes from these datasets.
  • Medium’ – data is relatively accessible but requires expertise to interpret or transform. To understand the data in a climate hazard and risk context, as well as planning outcomes, specific expertise in either climate, or GIS will be required.
  • ‘Low’ – a dataset which requires specialist knowledge, expertise or skills. Extensive expertise, as well as time and effort will need to be applied to this data in order to arrive at indicators that can be used to make planning decisions.

Data Licensing

The information is provided as guidance on the description and general consequences of the common license types encountered for data. However, care should always be taken to ensure that if any data is used, the license and its limits should be validated before use or distribution.

Table 9.1 – Relevant data licences and their impact on planning authorities

License Name

Description

Outcomes for planning authorities

Link

OGL – Open Government License

A UK government defined license that encourages the public sharing of government created data

OGL generally supports data being used for most purposes internally at a local authority, and shared publicly in full

Open Government Licence (nationalarchives.gov.uk)

PSGA – Public Sector Geospatial Agreement

The license under which premium Ordnance Survey data is licensed to UK central and local governments

The PSGA license generally supports planning authorities in using data internally for all government functions. However, the data cannot be published and shared publicly in full. OS provides details on the full obligations.[19]

Public sector licensing guide | OS (ordnancesurvey.co.uk)

CC-BY – Creative Commons Attribution

A permissive public copyright license that enables the free distribution of copyrighted work

CC-BY generally supports data being used for most purposes internally at a local authority, and shared publicly in full, so long as attribution is given.

There are many sub types of Creative Commons licenses, so refer to the Creative Commons site for more details

Deed – Attribution 4.0 International – Creative Commons

BSD – Berkly Software Distribution

A permissive, free software license

BSD is licenses are generally for software rather than data, but it is a very permissive license that imposes few limits on what can be done – a local authority could use BSD licensed software for any use internally, and then publish publicly in full

BSD licenses – Wikipedia

Copyright or Proprietary

Some of the datasets listed carry specific licensing terms. These must be validated against the specific use cases in any instance.

Refer to the given license directly – but generally, there will be limits to internal use and external publishing.

N/A

Data Scale and Resolution

Table 9.2 – Description of the shorthand terms used to describe spatial resolution as used in this report. Inset maps © OpenStreetMap contributors

Scale

Spatial Resolution

Example

‘street’

<50cm

A small map - it is showing an area the size of Edinburgh Castle

‘neighbourhood’

50cm – 1km

A small map - it is showing an area the size of Edinburgh city centre

‘town’

1km – 15km

A Small map - it is showing an area the size of Edinburgh

‘regional’

15km+

A small map - it is showing an area the size of the Lothians

‘national’

100km+

A small map - it is showing the entirety of Scotland

 

Example Tools to support Interpretation

Climate Risk Vulnerability Assessment methods – the University of Birmingham

A screenshot of the Birmingham City Council Climate Risk and Vulnerability Map showing the climate risk layer. The climate risk layer ranges from low (yellow) to high (red). A Climate Risk and Vulnerability Assessment (CRVA) map is a method co-developed by the WM-Air project team at the University of Birmingham with local and regional stakeholders across Birmingham and the West Midlands. A CRVA map shows how geospatial climate risk data may be used by local planning authorities. It is pulled together using different environmental, physical, and socio-economic datasets to understand how climate risk varies across an area. The mapping approach prioritises using publicly accessible data and can be replicated by other planning authorities to improve climate resilience (Greenham et al., 2023).

Figure 4 – Birmingham City Council Climate Risk and Vulnerability Assessment map

Birmingham City Council recently published their CRVA (Greenham et al., 2023) on the city’s website (Birmingham City Council, 2024). The CRVA map scores areas of Birmingham based on compiling the presence and extent of 11 different factors that may influence the impact of climate change, where the higher the score, the more at-risk and vulnerable an area and its citizens are likely to be to climate change. The approach is considered a Minimum Viable Product (MVP), i.e. it works, and refinements can be made through use.

A screenshot of the West Midlands Combined Authority Climate Risk and Vulnerability Map showing the climate vulnerability layer. The climate vulnerability layer ranges from low (blue) to high (yellow).
West Midlands Climate Risk and Vulnerability Assessment (WM-CRVA) Map

Figure 5 – West Midlands Combined Authority Climate Risk and Vulnerability Assessment Map

The University of Birmingham also collaborated with the West Midlands Combined Authority (WMCA); co-developing a CRVA map for the wider West Midlands (Greenham et al., 2024a). It takes forward the Birmingham MVP approach by including greater consideration of vulnerability. The overall CRVA map scores are based on 24 different factors, each of which is considered one of either a hazard, vulnerability, or exposure factor influencing climate risk.

Methodology

Our approach included two key phases the Discovery phase and the Analysis phase. The discovery phase involved a continuation of planning and refining the scope, and identifying the key tasks needed to ensure we had the full background and context to successfully undertake the research. The Analysis phase involved the main research tasks, including stakeholder engagement and a deep dive analysis of currently available climate risk and hazard data. Both are described in more detail below.

Discovery Phase

  • A desktop literature review was conducted (August 2024). The literature included covered information on climate change methods, past climate risk or vulnerability studies (where spatial data was used), and information relevant to climate risk in Scotland as well as the latest policy documents around climate adaptation for Scotland. Here we identified which risks were commonly highlighted within Scotland and what data has been used by others to represent those risks. As well as summarising the key policies relevant to the topic climate change risk and adaptation for the Evidence reports. The literature review findings were summarised in an excel spreadsheet. The full references to the literature are included in Appendix Literature review (Section 9.4.1).
  • Three of the currently available evidence reports were also reviewed, this allowed us to understand the current work by planning authorities and what approaches they took. We also began to identify gaps between the produced Evidence reports and the requirements.
  • A long list of potential workshop invitees was developed, this was to be refined within the analysis phase.
  • Identified a proposed list of relevant data with key search parameters for deep dive assessment. Research partners the University of Birmingham shared the data lists for both their CRVA mapping projects for Birmingham City Council and the West Midlands Combined Authority for review in the context of identifying the same UK wide datasets of their Scottish equivalents.
  • Set out an initial stakeholder engagement plan for the approach to both the interviews and a workshop, which was reviewed by and agreed with CXC.

Analysis Phase

  • Undertook the dataset deep dive and identified key practical characteristics including cost, availability, and accessibility
  • In the stakeholder engagement plan the approach for both the interviews and workshops were also set out. For the interviews we identified a list of stakeholders, this included three planning authorities that had or were in the process of undertaking the Evidence reports. We asked to speak to relevant individuals who had written the reports or who would be or were significantly involved in gathering climate evidence. Here, knowledge gained from the literature review was used to develop appropriate questions to help us better understand the local authority’s approach to gathering evidence, their understanding of the requirements and any difficulties they had faced or anticipated facing, and confidence with the topic (a full list of the interview questions can be found in Appendix Interview responses, Section 9.4.2).
  • When selecting stakeholders for both interviews and workshops we aimed to get a mix of stages within the development report process. We also ensured we had a good geographic spread of participants representing the wide range of planning authorities in Scotland. This included, coastal, city based, and Island based planning authorities.
  • During this analysis phase we held three interviews with representatives of Fife Council (21st August 2024), Comhairle Nan Eilean Siar (28th August 2024) and Glasgow City Council (3rd September 2024). Interviews included multiple members of the Arup team representing planning, Climate and data expertise as well as a note taker. All interviews were recorded with the permission of the participants. Interview findings were summarised in Appendix Interview responses (Section 9.4.2).
  • After the initial interviews a virtual ‘Prioritisation Workshop’ (17th September 2024) which included representatives from the planning authorities we interviewed, other planning authorities (across a geographic spread and at differing stages in their LDP) and other relevant wider stakeholders (such as representative from Sniffer). The workshop was developed using the findings of the interviews, so that the activities probed at areas of interest and or areas not fully covered by the interviews. The aim of this workshop was to further discuss how planning authorities can improve their access to geospatial data for climate adaptation.

Underlying assumptions

CXC facilitated introductions to key stakeholders for engagement. Engagements were virtual, via Microsoft Teams.

The sample of planning authorities involved was not aiming to be extensive or include all Scottish LPAs, given the scope, size and duration of this research project, but aimed to have good representation across geography, size and stage of progress with the Evidence report.

Literature review and stakeholder engagement

Literature review

A desktop literature review was conducted during the discovery phase, and a full list of references is provided here.

Table 9.3: Full list of references for literature review

Full reference

Link

Birmingham City Council (2024) Climate Risk and Vulnerability Assessment map.

https://maps.birmingham.gov.uk/webapps/CRVA/

Bristol City Council (2021) “Keep Bristol Cool”

https://bcc.maps.arcgis.com/apps/instant/portfolio/index.html?appid=986e3531099f48d393052fab91ceff51

Centre for Sustainable Energy and the Town and Country Planning Association (2023) Spatial planning for Climate resilience and Net Zero (CSE&TCPA). UK Climate Change Committee

Spatial planning for climate resilience and Net Zero (CSE & TCPA) – Climate Change Committee (theccc.org.uk)

Climate Ready Clyde – Glasgow City Region (GCR) Climate Vulnerability Map 2022

GCR Climate Vulnerability Map 2022 (arcgis.com)

Climate Ready Clyde: Climate Risk and Opportunity Assessment for Glasgow City Region (2022)

Climate Ready Clyde

Falkirk Council (2024) Falkirk Local Development Plan 3 Evidence report

Topic Paper – Energy, Climate Change and Resources (falkirk.gov.uk)

Fife Council (2024) Fife Local Development Plan 2 – Evidence report

01-The-Evidence-Report-with-images-Council-version.pdf (fife.gov.uk)

Glasgow City Council (2024) City Development Plan 2 Evidence report

CDP2 Climate Mitigation and Adaptation (glasgow.gov.uk)

Greater London Authority (2022) London Climate Risk – A Spatial Analysis of Climate Risk Across Greater London: Methodology Report.

https://data.london.gov.uk/dataset/climate-risk-mapping

Greenham, SV., Ferranti, EJS., Cork, NA., Jones, SA., Zhong, J., Haskins, B., Grayson, N., Needle, S., Acton, WJF., MacKenzie, AR., Bloss, WJ. (2024b). Mapping climate risk and vulnerability in the West Midlands. A guidance document produced by the WM-Air project, University of Birmingham

https://doi.org/10.25500/epapers.bham.00004371

Greenham, SV., Jones, SA., Ferranti, EJS., Zhong, J., Acton, WJF., MacKenzie, AR., Grayson, N., 2023. Mapping climate risk and vulnerability with publicly available data. A guidance document produced by the WM-Air project, University of Birmingham.

Mapping climate risk and vulnerability with publicly available data. A guidance document produced by the WM-Air project, University of Birmingham. – ePapers Repository (bham.ac.uk)

Kent and Medway Council (2020) Kent and Medway Climate Change Risk and Impact Assessment​

https://www.kent.gov.uk/__data/assets/pdf_file/0015/111381/CCRIA-for-Kent-and-Medway-part-one-methodology-and-summary-findings.pdf

Met Office (2024) Spatial Climate Risk Assessments: A tool for understanding future risk and adaptation planning. Insights.

Spatial Climate Risk Assessments: A tool for understanding future risk and adaptation planning – Met Office and its Local Authority

Perth and Kinross Climate change risk and vulnerability assessment (in press)

NA – not published

Ricardo (2023) Surveying the evidence landscape for UK-focused spatial climate risk assessment.

Surveying the evidence landscape for UK-focused spatial climate risk assessment (Ricardo) (ukclimaterisk.org)

Scottish Government (2019) Climate Ready Scotland: Second climate change adaptation programme 2019-2024

Climate Ready Scotland: climate change adaptation programme 2019-2024 – gov.scot (www.gov.scot)

Scottish Government (2023b) Local Development Planning Guidance

Local development planning guidance (www.gov.scot)

Scottish Government (2024) Scottish Climate Change Adaptation Programme: progress report 2023 to 2024

Scottish Climate Change Adaptation Programme: progress report 2023 to 2024 – gov.scot (www.gov.scot)

Scottish Government / Riaghaltas an h-Alba (2024) Draft Scottish National Adaptation Plan (2024-2029): Actions today, for a climate resilient future. 31 January 2024.

Supporting documents – Climate change – national adaptation plan 2024 to 2029: consultation – gov.scot (www.gov.scot)

Sniffer (2021) Third UK Climate Change Risk Assessment (CCRA3) Technical Report: Summary for Scotland

Summary for Scotland (CCRA3-IA) – UK Climate Risk

UK Climate risk indicators (2024) University of Reading and Institute of Environmental Analytics.

https://uk-cri.org/

West Midlands Combined Authority (2024) Climate Risk and Vulnerability Assessment map.

West Midlands Climate Risk and Vulnerability Assessment (WM-CRVA): LSOA — West Midlands Combined Authority (west-midlands-combined-authority.github.io)

Interview responses

This section provides the interview questions and a summary of the answer given by all three planning authorities interviewed.

Q1: What is your role in preparing the Evidence report?

  • Most stakeholders interviewed were planning officers based in planning services or equivalent.
  • Teams working on this topic of the Evidence report ranged from 1-2 to 4-5 members of staff as the core team. Though generally one or two key individuals took responsibility or a key co-ordination role.
  • Use of expertise outside of teams also varied including some drawing on data individuals or climate and sustainability officers.

Q2: What is the status of your Evidence report? And what are the next steps?

  • Ranged from early stages of prep to just complete and complete and addressing feedback.

Q3: How clear to you were the requirements / guidance for assessing climate risk through the Evidence report?

  • Responses to this question were mixed, some stated the guidance “left a lot open to interpretation”, feeling it was hard to understand what they actually needed to do.
  • One Local Authority said the guidance was clear in answer to this question but after further probing it appeared they were not sure on several of the elements within the requirements.
  • One response stated that requirements were easier to interpret due to knowledge of other resources.

Q4: How did you assess climate risk/climate change within your Evidence report?

  • In one interview the approach had not been developed and it was too early to discuss.
  • The other two planning authorities relied heavily on information that had been previously produced for the area, such as past climate profiles or regional risk assessments. Using this information and interpreting it rather than new information or raw data designed specifically for the Evidence report.
  • One Local Authority took a place-based approach but struggled with assessing climate risk on this level.

Q5: How have you assessed vulnerability to climate change and inequalities?

  • This question was generally not well answered indicating that there was a lack of understanding on the requirements around assessing vulnerability.
  • One Local Authority alluded to have a copy of a vulnerability index, but not sure where it was sourced from (potentially from SEPA).

Q6: Do you know what datasets were required to undertake climate risk assessment? 

  • One Council in the early stages indicated that they did not yet know what datasets would be required to complete assessments but were aware of the recommended data sets.
  • Another realised on using report summarising previous regional risk assessments and interpreted screenshots from these reports. They had tried to get the data but had difficulty locating/accessing it.
  • Generally, when talking about data the focus was flood data. No participant mentioned raw climate projection data. Heat hazard data was mentioned by a single Local Authority but in the context of difficulties getting the data.

Q7: Do you know how to/have the ability to access them (within the team)?

  • Answers for this question were mixed some had dedicated contacts they could reach out too for data others stated they struggled knowing which data was relevant.
  • When probed there generally seemed to be a lack of knowledge on what data was out there, without even thinking about how to access, use and interpret the data.
  • General staff resources were flagged as an issue and time needed to use datasets.
  • One Local Authority had external GIS support for these kind of tasks from a cross local authority collaboration to share resource, with a 2-year secondment, though this was a resource with a limited timescale.

Q8: Is there anything else you would like to share about the process?

  • One set of interviews mentioned that they were beginning to realise the size and scope of the task of gathering and analysing climate risk data as they begin process of evidence gathering.
  • One Local Authority mentioned concern about understanding how all of this actually linked into to planning and how in general the evidence would be used to influence planning.
  • One also mentioned they had a lot of support from their climate team and could sense check and problem solve with their guidance. This was an invaluable resource.

Workshop

Arup and the University of Birmingham undertook a stakeholder workshop on 17 September 2024 for ClimateXChange Scotland and the Scottish Government on Improving access to geospatial climate risk data. The purpose of this workshop was to discuss together how planning authorities can improve their access to geospatial data for climate adaptation in the context of development planning.

The online workshop brought together planning authorities (across a geographic spread and at differing stages in their LDP) to better understand their needs as a local planning authority and/or climate policy team:

  • to prepare Evidence reports, 
  • as users of this geospatial climate risk data and;
  • understand any current challenges or gaps that need addressing

The workshop provided information on key hazards and risks the planning authorities had been or anticipated focussing on and what data would or had been used. The workshop built on the interviews by delving deeper into the data and methods of analysis. Providing further insight on data gaps, ease of use and challenges faced by the planning authorities.

Additional Resources

Data catalogue

The data catalogue spreadsheet is available online:

Improving access to geospatial climate risk data – Data catalogue

Briefing note for planning authorities

The briefing note for planning authorities is available online:

Geospatial climate data for evidence reports briefing note

How to cite this publication:

Corrigan, J., McNeill, C., Kent, N., Keane, M., Brown, C., Hanson, D., Halliday, C., Ferranti, E., Greenham, S., Horrocks, L., Doherty, J. (2025) ‘Improving access to geospatial climate risk data’, ClimateXChange. http://dx.doi.org/10.7488/era/5650

© The University of Edinburgh, 2025
Prepared by Arup and the University of Birmingham on behalf of ClimateXChange, The University of Edinburgh. All rights reserved.

While every effort is made to ensure the information in this report is accurate, no legal responsibility is accepted for any errors, omissions or misleading statements. The views expressed represent those of the author(s), and do not necessarily represent those of the host institutions or funders.

This work was supported by the Rural and Environment Science and Analytical Services Division of the Scottish Government (CoE – CXC).

ClimateXChange

Edinburgh Climate Change Institute

High School Yards

Edinburgh EH1 1LZ

+44 (0) 131 651 4783

info@climatexchange.org.uk

www.climatexchange.org.uk


  1. The LDP is required under The Town and Country Planning (Scotland) Act 1997 (Scottish Government, 1997), as amended by the Planning (Scotland) Act 2019 (Scottish Government, 2019). Relevant secondary legislation and published guidance includes The Town and Country Planning (Development Planning) (Scotland) Regulations 2023 (Scottish Government, 2023a) as well as Local Development Planning Guidance (Scottish Government, 2023b).



  2. A detailed description of licensing terms and their implication, such as OGL, PSGA, BSD and CC-BY are provided in 9.1.2 – Data Licensing



  3. The relevance of the dataset to the hazard groups as discussed with participants. Definitions are shown in Table 1



  4. Captures ease of use by local authority officials. See 9.1.1 – Usability for more detail



  5. New deal for agriculture – gov.scot



  6. A detailed description of licensing terms and their implication, such as OGL, PSGA, BSD and CC-BY are provided in 9.1.2 – Data Licensing



  7. The relevance of the dataset to the hazard groups as discussed with participants. Definitions are shown in Table 1



  8. Captures ease of use by local authority officials. See 9.1.1 – Usability for more detail



  9. LCZ Generator



  10. https://forest-fire.emergency.copernicus.eu/apps/effis_current_situation/index.html



  11. https://www.scottishairquality.scot/



  12. https://wcr.ethz.ch/research/climada.html



  13. https://tyndall.ac.uk/projects/openclim/



  14. Administered by the Planning and Environmental Appeals Division, the Gate Check is a process through which the sufficiency of the evidence report is assessed, to confirm there is a sound evidence base on which to prepare a Local Development Plan



  15. From an LDP guidance perspective the evidence available at the time of writing the report is proportionate and sufficient.



  16. https://climatereadyclyde.org.uk/



  17. https://www.4earthintelligence.com/capabilities/heat/



  18. https://climatereadyses.org.uk/



  19. https://www.ordnancesurvey.co.uk/customers/public-sector/public-sector-licensing/publish-share-data


The agriculture policies outlined in the Update to the Climate Change Plan (CCP) provide a route map for agricultural transformation to reduce greenhouse gas emissions. They take a co-development approach and work with stakeholders and farmer-led groups to secure increased uptake of low-emission farming measures through new schemes and approaches.

This project examined the potential reductions in livestock methane emissions through breeding, and the policy levers that could motivate these changes.

Findings

  • Breeding could reduce methane emissions from the digestive process in livestock by up to 9.5% by 2045.
  • Actions and behaviour changes will be required of Government policymakers, pre- and post-farm gate actors and farmers, with key barriers being lack of knowledge and perceived cost.
  • Scotland has a well-developed research base around breeding livestock for reduced emissions, placing it in good stead to develop further work in this area.
  • Relevant technologies that could be mainstream in Scotland by 2030 include a national breeding programme, sexed semen and the breeding potential of an animal for a specific trait.
  • There are very few instances of methane detection methods being used on farm in the UK. The use of proxies such as mid-infrared spectra in milk could be encouraged to determine methane emissions.
  • There are many reproductive technologies already in use, particularly in the dairy industry. The report estimates these to be mainstream across the cattle sector by 2045, with lower uptake in the sheep sector due to artificial insemination being a complex procedure.

For further details, please read the report.

If you require the report in an alternative format, such as a Word document, please contact info@climatexchange.org.uk or 0131 651 4783.

Research completed: May 2024

DOI: http://dx.doi.org/10.7488/era/5569

Executive summary

The agriculture policies outlined in the Update to the Climate Change Plan (CCP) provide a route map for agricultural transformation, to reduce greenhouse gas emissions. They take a co-development approach and work with stakeholders and farmer-led groups to secure increased uptake of low-emission farming measures through new schemes and approaches.

This project examined the potential reductions in livestock methane emissions through breeding, and the policy levers that could motivate these changes.

We began by exploring the technologies that detect and measure methane, manage data and are used in the breeding process. This included considering the availability of these technologies in Scotland in 2030 and 2045, with practical considerations for a Scottish context, and identifying the breeding traits that can lead to lower methane emissions.

We then identified the relevant policy levers and behaviour changes and considered what Government, the post-farm market, pre-farm gate actors and farmers can do differently to encourage methane reductions through breeding.

Key findings

  • By 2045, breeding could reduce methane emissions from the digestive process in livestock, known as enteric methane, by up to 9.5% (382.2 kt CO2 equivalent). This is under the “Policy changes” scenario, where legislation will require farmers to introduce methane reducing breeding techniques to their herds (with uptake rates of 100% in dairy, 80% in beef, and 60% in sheep).
    • This includes a 6.8% reduction in emissions from beef, 6% from dairy and 17.5% from sheep.
    • This reduction is achieved by selecting traits for methane efficiency (methane production, intensity and yield), feed efficiency, offspring carcass weight, milk yield and milk fat and protein when choosing breeding stock.
    • Our research highlighted selective breeding for feed efficiency as a promising option. This is because, despite its lower methane reduction potential, it builds on a practice that is already well understood by farmers.
  • To achieve emission reductions, actions and behaviour changes will be required of Government policymakers, pre- and post-farm gate actors and farmers. We found key barriers were lack of knowledge and perceived cost.
  • Scotland has a well-developed research base around breeding livestock for reduced emissions, placing it in good stead to develop further work in this area. Funding could be targeted towards building on this research, with more data points to support innovation and enhance the robustness of results. Further research could include the potential for a specific methane reduction target to increase clarity and focus action. Funding would be useful if targeted to better communication of the research findings to inform farm advisers, pre- and post-farm actors and supporting farmer peer-to-peer learning. Collaboration between stakeholder groups will achieve greater progress.
  • Relevant technologies include methods to detect and measure enteric methane in animals, data management, reproductive technologies and genomics. Those that could be mainstream in Scotland by 2030 include a national breeding programme, sexed semen and the breeding potential of an animal for a specific trait, known as estimated breeding values. The interaction between technologies is key to success. For instance, the wide use of data management tools will depend on the wide use of genomics to collect data.
  • We found very few instances of methane detection methods being used on farm in the UK. We therefore believe it is unlikely these will be used beyond research and innovators by 2045. As such, we recommend encouraging the use of proxies such as mid-infrared (MIR) spectra in milk to determine methane emissions.
  • Many reproductive technologies are already in use, particularly in the dairy industry, so we estimate these to be mainstream across the cattle sector by 2045. We estimate lower uptake in the sheep sector due to artificial insemination being a complex procedure. However, as sheep start breeding at an early age and often have multiple births per animal, there is greater potential for emission reductions if low-emitting traits are introduced into the herd such as through a ram.

On this basis, we think there is a strong foundation for breeding for reduced methane emissions to contribute to Scottish Government’s methane and climate commitments and to support Scottish livestock farmers’ future resilience. 

Glossary / Abbreviations

AI

Artificial insemination

DNA

Deoxyribonucleic acid is an organic chemical that contains genetic information and instructions for protein synthesis

EBVs

Estimated breeding values

DMI

Dry Matter Intake

FAO

Food and Agriculture Organisation

Gene

A genetic sequence that contains information on specific traits.

Genetic modification

Any process by which genes are changed or deleted in order to adjust a certain characteristic of an organism. It is the manipulation of traits at the cellular level.

Genetic selection

Selecting for specific genes that carry desirable traits.

Genetics

The study of how genes are passed down from one generation to the next.

GHG

Greenhouse gas

CO2

Carbon dioxide

ICBF

Irish Cattle Breeding Federation

Methane

A powerful greenhouse gas, a chemical compound with the chemical formula CH4.

Microbes

Microscopic organisms

Microbiome

A collection of microbes (e.g. bacteria) that occur in the rumen.

NERC

Natural Environment Research Council

PAC

Portable Accumulation Chambers

Precision breeding

Amends sections of DNA by adding or moving genetic material

Proxy

An object/thing that is being used in the place of something else

REA

Rapid evidence assessment

Rumen

The specialised stomach of a ruminant (e.g. cow) that digests feed by microbial fermentation.

Ruminant

Animals, including cattle and sheep, that have more than one stomach and have the ability to bring food up from their stomach and chew it again.

Selective breeding

Choosing animals that carry desirable traits to be bred so that the traits are passed on to their offspring.

Traits

Specific characteristics that are genetically determined.

Introduction

Methane is a powerful greenhouse gas (GHG), 28 times more potent than CO2, produced as a by-product of the ruminant digestive process called enteric fermentation. During enteric fermentation, microbes digest feed in a specialised stomach, known as the rumen, subsequently releasing enteric methane. In 2021, enteric fermentation from ruminant livestock, such as cattle and sheep, was responsible for 48% of GHG emissions from agriculture in Scotland.

The UK signed the Paris Agreement, committing to limit global warming to 1.5°C and is a signatory of the Global Methane Pledge, aiming to reduce global methane emissions by at least 30% from 2020 levels by 2030. The Climate Change (Emissions Reduction Targets) (Scotland) Act 2019 outlines a net zero target for Scotland by 2045, with a 75% reduction in emissions by 2030. The strategy to meet these targets is laid out in Scotland’s Climate Change Plan (CCP) 2018-2032 and Climate Change Plan Update (CCPU).

One potential way to reduce emissions from the livestock sector is to select breeding traits in livestock that lead to lower methane emissions.

Traditional breeding programmes select cows or ewes producing offspring with desirable characteristics to either produce meat, milk or fibre, or to continue in the breeding herd. This method relies on waiting for the offspring to mature before the desired traits can be identified. The use of genetic technologies allows desired traits to be chosen at the point of breeding, giving a more assured outcome at an earlier stage.

Genetics are already used to facilitate precision breeding to improve livestock performance. As genetic changes are permanent and cumulative, it is an attractive option for targeting and reducing GHG emissions from ruminants (González-Recio et al., 2020; Manzanilla-Pech et al., 2021; Rowe et al., 2021).

Scottish research is at the forefront in breeding livestock for reduced methane. A recent project by the Roslin Institute highlighted the strong relationship between the rumen microbiome and methane emissions; SRUC has several relevant research studies (published and ongoing), with research facilities such as GreenCow measuring GHG emissions, and Moredun has researched the impact of livestock health and welfare on methane emissions. In 2023, Defra awarded £2.9 million to the sheep sector to launch ‘Breed for Ch4nge’ which aims to measure methane from 13,500 sheep to improve the efficiency of the UK flock; some of the research is taking place on Scottish farms.

The issue is of interest internationally. New Zealand research has shown that breeding for reduced emissions in sheep does not impact productivity and health; Canadian traders are marketing dairy semen with methane efficiency traits, and beef farmers in Ireland are being paid to take part in genomic programmes.

Please note, reducing methane through dietary amendments (such as feed additives) is out of scope for this project.

Project aims

This research project has two key aims:

  1. To understand the methane emission reductions that could be achieved in Scotland through breeding. We do this by identifying technologies that detect and measure methane, manage data and are involved in the breeding process. We look at the likely availability of these technologies in Scotland in 2030 and 2045, with practical considerations. Finally, we identify the breeding traits that can lead to lower methane emissions and quantify these.
  2. To identify what is needed to support this through policy levers and behaviour change. Using the findings of our literature review and stakeholder consultation, we suggest behaviour changes and discuss their impacts.

Identifying the evidence

To better understand where and how methane emissions could be reduced for project aim 1, we performed a Rapid Evidence Assessment (REA) and a series of stakeholder interviews[1] (now on referred to as our review) to understand:

  • The technologies involved in reduced emission breeding;
  • The important traits to select for reduced emissions;
  • Emission reduction values;
  • The benefits and challenges of breeding for reduced emissions;

The review also sought evidence on what is needed to support further uptake of these technologies in Scotland, for project aim 2.

The technologies involved in breeding for reduced emissions

We grouped the technologies used to identify livestock with low methane emissions into four categories: detection methods, data management, reproductive technologies and animal genomics.

We found little information regarding the timeline of availability for the technologies on farms in Scotland. In the stakeholder interviews, many were not aware of specific technologies being used unless they were directly involved in research. Our research did find international evidence, for example, portable accumulation chambers (PAC) in New Zealand support The Cool Sheep™ Programme. Due to this limited data on timing, we categorised the availability of the technology in Scotland in 2030 and 2045 under the following headings:

Experimental (E): used in research only, with no use on Scottish farms.

Innovative (I): used in trials on Scottish farms by a few innovators.

Mainstream (M): considered mainstream and being used on Scottish farms.

Future possibility (FP): unlikely the technology will be used by 2030 or 2045, however not ruling out its availability in the future.

Not applicable (NA): not relevant to the sector.

The rate of technology uptake will differ between and within sectors. For instance, dairy cattle are milked multiple times a day, providing an opportunity to closely assess individuals interacting with the technology. For the same assessment in the beef and sheep sectors, the grazing nature of the system may require cultural and habitual change for widespread uptake (Jones and Haresign, 2020). Farmers also have different interests, business structures, cash flow etc which impacts their decisions on changing farm practices.

Cost was excluded from our review due to the complexities in estimation. The cost of a technology is likely to depend on the individual farm situation, for example, the number of livestock or proximity to infrastructure or manufacturers. Technologies requiring installation may vary depending on whether adjustments are required to an existing building.

We understand the technologies presented below have the potential to be used in Scotland. The full list of technologies discovered in our research can be found in Appendix A, section 9.1.

Detection methods

Detection methods are used to detect and measure enteric methane to identify which animals emit less. Examples include a respiration chamber which measures the difference in methane emissions with and without the animal, while spot sampling uses head chamber systems or hand-held lasers to take short-term measurements from the animal’s breath (Tedeschi et al., 2022). Further examples can be seen in Table 1.

We found very few instances of detection methods being used in UK research, but we estimate that some will be available in 2030 and more by 2045 (see Table 1). However, as detection methods are primarily a research tool, it is unlikely they will be used beyond innovators by 2045. Practical constraints such as large technological components and measuring a few animals at a time make it challenging to introduce respiration chambers (which are considered the ‘gold standard’ of measurements) on a large scale (Manzanilla-Pech et al., 2021; Rowe et al., 2020). As such, we recommend encouraging use of proxies such as mid-infrared (MIR) spectra in milk to determine methane emissions.

Portable Accumulation Chambers (PACs) have been launched recently by scientists at Scotland’s Rural College (SRUC) for use across the UK. The two units (of 12 trailers) are currently only being used for research purposes. Each trailer holds 12 chambers and is capable of measuring between 60 – 80 sheep per day providing breeding values for methane emissions for representative samples of sheep within a breeding programme (Duthie et al., 2024)

New Zealand currently incorporates the use of PACs in breeding programmes through The Cool Sheep™ Programme, where breeders use PACs to measure and select for low-emitting rams available for breeding. Research trials are underway in countries such as Australia, Norway and Uruguay and now the UK. This technology provides a promising option for Scotland as it is transportable between farms and has a short measurement period which limits stress in livestock. However, current research trials on UK sheep systems need to be completed before PACs can be used widely (Duthie et al., 2024).

Data management

Data management technologies are essential to store, share and analyse data, while also tracking individuals and breeding lines with desired traits to improve target outcomes (including emissions reductions).

The dairy sector is advanced in this area compared to beef and sheep sectors, with established tools for monitoring and measuring production characteristics. Stakeholders discussed the possibility to enhance or repackage these tools and platforms, such as ScotEID, to incorporate methane traits. Using a tool that is familiar for farmers might reduce resistance for adoption.

  1. Case study: New Zealand

N-Prove is a free website tool for New Zealand farmers to find the best rams for breeding. Using a series of button­­­­­s and slider scales, farmers can customise what traits they are looking for in a ram. NProve then generates a list of breeders with rams that best fit. Farmers can select terminal or maternal traits, as well as breeders based on location, breed and exclude certain flocks from results. Methane production is an option to select from the maternal traits. The tool is free to use and registration is not required. The tools anonymity means farmers can gather their options for the best breeder for their farm. NProve sources data from a central database and genetic evaluation service (SIL database) that holds information for more than 600 flocks, making it one of the largest genetic evaluations of sheep in the world. This tool could be used in a similar fashion for other species in other geographies as long as an appropriate database was available or was developed to source information.

Data technologies rely on wider infrastructure, such as website portals or cross-country collaboration, making it challenging to estimate the availability for 2030 and 2045. However, there is high potential. Stakeholders discussed that a risk for these technologies is the lack of interest and uptake from farmers, so it is important to inform and engage the industry regarding their benefits.

These technologies offer benefits for farmers by improving the understanding of the genetic qualities of their livestock and having a head-start on understanding the genetics and traits being brought into the herd. See Table 2 for the relevant data management technologies.

Table 1. Examples of the detection methods involved in breeding livestock for reduced methane emissions. Please see Appendix A, section 9.1 for the full list of the technologies found in our review.

 

Description

Livestock Sector

Data collected

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M),

Future possibility (FP), Not applicable (NA)

Practical considerations in Scotland

Beef

Dairy

Sheep

 

Automated head chamber system (e.g. GreenFeed)

A head chamber unit that can be positioned in housing or pasture. Feed is used to attract livestock to the unit (van Breukelen, 2023; Zaman et al., 2021).

All

Methane and CO2 concentrations

Non-invasive.

Can be set up in grazing fields or in housing.

Portable

High purchase and running costs.

A spot measurement, not a true reflection of emissions per day.

Feed to attract livestock increases costs.

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

No evidence was found for use in the UK. It could be a feasible option for Scotland due to the benefits of transportability and ability to measure grazing livestock.

Mid-Infrared (MIR) data

MIR spectroscopy is used to predict the fat and protein content of milk. As methane is linked to milk composition, the latter can be used as a proxy to predict methane emissions (Dehareng et al., 2012; Semex, 2023).

Dairy

Milk components such as lactose, protein and fat

MIR technology is already used routinely in milk recording. Therefore providing an existing infrastructure to integrate methane reporting to.

Because it is a proxy, validation of results (for example with a respiration chamber) is required (Denninger et al., 2020).

NA

2030: I

2045: I

NA

No evidence found of MIR in the UK to estimate methane, but European examples were found. The data could become available through existing milk recording schemes, so it could be introduced by innovators by 2030. If the need for verifying results via detection methods is removed, this could be mainstream by 2045.

Portable accumulation chambers (PAC)

A portable respiration chamber which takes measurements over a short period of time (e.g. 1 hour) (Cummins et al., 2022).

All

Methane and CO2 concentrations

Quick measurement period reduces animal stress (Cummins et al., 2022).

Transportable (NZHerald, 2023).

Feeding and management protocols must be followed prior to measurements (Duthie et al., 2024).

Not suitable for long-term measurements (Cummins et al., 2022).

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

A promising option for Scotland as it is transportable between farms. SRUC recently acquired a PAC for sheep. However, current research needs to be completed before they can be used widely (Duthie et al., 2024).

Handheld lasers

A handheld device originally developed to detect gas leaks can measure concentrations of methane in livestock breath (Sorg, 2021).

All

Methane concentration

Non-invasive and portable.

Can take measurements from grazing livestock.

Can take measurements from several animals in one day.

Results can be sent to a smart phone (Sorg, 2021).

Has a lower accuracy, measurements are highly affected by environmental conditions (de Haas et al., 2021; Sorg, 2021).

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

No evidence found for use in UK research. However, the benefit of taking measurements from several animals in the same day may make it an attractive option for Scotland. Its widespread use may depend on supporting infrastructure such as reporting systems.

Table 2. Examples of data management tools involved in the process of breeding livestock for reduced methane emissions. Please see Appendix A, section 9.1 for the full list of the technologies found in our review.

 

Description

Sector

Data collected

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M),

Future possibility (FP), Not applicable (NA)

Practical considerations in Scotland

Beef

Dairy

Sheep

nProve

A free tool for New Zealand farmers to use to choose rams for breeding. They can choose the terminal or maternal traits that fit their breeding goals. When choosing maternal traits, methane production is an option.

Sheep

Reproduction, lamb growth, size, meat, wool, health indices, methane production.

User friendly.

Farmers can choose rams based on location, breed and exclude certain flocks from results.

 

NA

NA

2030: FP

2045: I

Success requires genetic evaluation and measuring methane (via PAC) to be common practice. Existing tools such as ScotEID (records births, deaths, and movements), and RamCompare (presents performance recorded ram data), could be repackaged to incorporate methane production.

National breeding programme

A programme which plans and identifies breeding objectives, traits and information on selection criteria

All

Methane emissions

UK wide

To be successful at a national scale, significant data, cooperation and initial funding is required.

2030: M

2045: M

2030: M

2045: M

2030: M

2045: M

In 2023, The National Sheep Association began a 3-year initiative to measure methane from 13,500 sheep to incorporate production traits into breeding programmes. With progress like this, it is possible that national breeding programmes will be mainstream by 2030.

Multi-country database

An international database that contains data from many livestock (Manzanilla-Pech et al., 2021).

All

performance/ production (trait-related) records

A larger dataset

improves robustness (Manzanilla-Pech et al., 2021).

Combining data from different countries can be challenging due to differences in reporting, recording, technology, favoured breeds and management style (Van Staaveren e al., 2023).

Sharing genetic information between countries requires compliance with the Nagoya Protocol.

2030: FP

2045: FP

2030: E

2045: I

2030: FP

2045: FP

Due to data sharing challenges, it is unlikely this will be available by 2045 in this context. There may be progress in the dairy sector due to the use of methane indexes, e.g. in Canada and the international scope of many dairy processors.

Bull catalogues (e.g. Genus Bull search)

This index allows farmers to see the scores of certain traits in bulls.

Dairy, beef

One of these traits is called Feed Advantage which can identify bulls with the greatest feed conversion (ABS, 2023).

Farmers can choose bulls with the desired characteristics to use in breeding.

 

2030: M

2024: M

2030: M

2024: M

NA

These are already available for farmers to use, so we would estimate them to be mainstream by 2030.

Reproductive technologies

Reproductive technologies are directly used for breeding. With many already in use on Scottish dairy farms, we estimate that it is likely most will be mainstream in the cattle sectors by 2045. We estimate lower progress in the sheep sector reflecting the current low uptake. Stakeholders discussed the reasons for low uptake in the sheep sector are due to the extensive nature of sheep farming in Scotland and less infrastructure for sheep in this area, such as semen collection and storage, the availability of which determines uptake. In addition to this, artificial insemination (AI) in sheep requires a vet to perform a surgical procedure (in cattle it can be done by a qualified farmer), adding a practical and financial hurdle.

Table 3. Examples of reproductive technologies involved in the process of breeding livestock for reduced methane emissions. Please see Appendix A, section 9.1 for the full list of the technologies found in our review.

 

Description

Sector

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M),Future possibility (FP), Not applicable (NA)

Practical considerations in Scotland

Beef

Dairy

Sheep

Artificial insemination (AI)

A technique to inseminate females, using fresh or frozen semen.

All

High success rate for cattle.

No requirement for a bull to be on the farm.

Better guarantee of uniform calving.

AI in sheep is often done by laparoscopic artificial insemination which is a surgical procedure done by a vet. Due to the scale and extensive nature of sheep farming, this brings practical challenges.

Relies on sufficient infrastructure to collect and store semen (Stakeholder comment, 2023).

2030: M

2045: M

2030: M

2045: M

2030: I

2045: I

AI is common practice in the dairy sector, with some use in the beef sector. It’s likely this will be mainstream by 2030 for cattle. Due to the practical challenges in sheep, it may still only apply to innovators.

Sexed semen

A method which allows control over the sex of the offspring by separating sperm cells based on their X or Y chromosome content. By focusing on females for example, there is the potential to reduce methane emissions by reducing the number of unwanted males (Duthie et al., 2024).

All

Increasing selection of females in the dairy sector improves productivity.

Success relies on the uptake of AI.

2030: M

2045: M

2030: M

2045: M

2030: I

2045: I

This is widely done in the dairy sector. Use in the beef sector is currently lower, however by 2030 there is the potential for this to be mainstream. Progress is determined by the uptake of AI in the sector. Due to the practical challenges associated with AI, it will likely remain an innovative practice in the sheep sector.

Conventional breeding

The use of bull/ram to cow/ewe breeding. Selecting cows or ewes producing offspring with desirable characteristics to remain in the breeding herd.

All

Minimal technical input.

Familiar practice for farmers.

Little control over selecting desirable traits.

Time intensive as it requires offspring maturity before seeing if they have the desired traits.

2030: M

2045: M

2030: M

2045: M

2030: M

2045: M

Already common practice for general breeding, so breeding for methane reduction could be mainstream by 2030.

Animal Genomics

Genomics is the study of the genome, a complete set of an organism’s DNA[2]. Genomics provides the opportunity to better understand how well an animal will perform based on its DNA profile. DNA and management both determine performance qualities, such as milk yield. Precision breeding (which is not genetic modification) amends sections of DNA by adding or moving genetic material. This has been used in the cropping sector to improve yields and/or disease resistance. In the livestock sector, research focusses on increased resilience to bovine tuberculosis and mastitis. In 2023, England introduced The Precision Breeding Act, outlining classifications for using precision breeding on crops and livestock, including how the products from them should be regulated, “Neither the Scottish nor Welsh Parliaments have granted legislative consent to the Bill.”.

Table 4. Examples of animal genomic technologies involved in the process of breeding livestock for reduced methane emissions. Please see Appendix A, section 9.1 for the full list of the technologies found in our review.

 

Description

Sector

Data collected

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M), Future possibility (FP), Not applicable (NA)

Practical considerations in Scotland

Beef

Dairy

Sheep

Microbiome-driven breeding

Emphasis is on selecting livestock with a rumen microbiome composition which is more efficient at fermenting feed so producing less methane.

All

Rumen fluid samples – sequencing of microbial DNA.

Potential method for improving animal health and reducing environmental impact.

This is a relatively new field and much is unknown about how the gut microbiome develops and is maintained over time.

It is unclear how much influence the animal may have over those processes.

2030: E

2045: E

2030: E

2045: E

2030: E

2045: E

Good early signs but still at research stage.

Genomic breeding values (GEBVs)

Values that are based on information from livestock DNA and measured performance. Can be used with EBVs to improve accuracy of breeding programmes. (Meat Promotion Wales. 2013).

All

DNA and performance records.

Can be used to identify traits that

are difficult to record.

Beneficial for traits measured in only one sex.

Useful for accurately measuring traits that occur later in life (Scholtens et al., 2020).

Accuracy of the estimate is dependent on the number of animals included in the reference population (Scholtens et al., 2020).

2030: I

2045: M

2030: M

2045: M

2030: I

2045: M

GEBVs are currently available for a number of carcass traits in Limousin cattle in the UK (Business Wales, 2016) and offered by the genetic company Genus.

Estimated Breeding values (EBVs)

Calculated from the performance data of recorded animals. Environmental factors (e.g. feeding) are filtered out to provide a genetic value for each trait (Stout, D. 2021).

All

Performance records – parentage and traits of interest (e.g. weight traits).

Provides a more objective (data driven approach) towards selection.

Genetic selection based on EBVs leads to faster rates of genetic gain and flock improvement (compared to selection based on raw data or basic observation).

Allows comparisons within breeds, not between breeds.

2030: M

2045: M

2030: M

2045: M

2030: M

2045: M

Use as a tool to aid in the selection of healthy and structurally sound animals.

Traits

Traits are specific characteristics of an individual (physical or behavioural) that are influenced by genes and environmental factors. Understanding the traits that lead to lower methane emissions is key to a successful breeding programme for methane emissions reduction.

It should be noted that the breeding focus, and therefore traits selected, depends on the farmer’s goals. For example, breeding for breeding stock would focus on selecting offspring traits, such as calving or lambing ease, while farms producing fat or store stock would focus on product traits, such as increased liveweight gain (Stakeholder comment, 2023). Currently, most traits are associated with productivity, such as increasing milk yield in the dairy sector. Progress in the beef and sheep sectors has been much slower, with fewer examples found of genetics used in breeding programmes.

The traits in Table 5 are used for breeding in global research to reduce methane emissions directly and indirectly. We have categorised these traits into the following groups:

Production – offspring: Traits associated with reproduction.

Production – product: Traits associated with products from the animal.

Functional: Traits that underpin the function of the animal and are not specific to production or emissions improvements.

Climate: Traits directly linked to reducing methane emissions.

Stakeholders and the literature emphasised that selection for methane reduction traits should ensure production traits, such as health, are not compromised (Stakeholder comment, 2023; Llonch et al., 2017). To look into this further, we examined performance and methane efficiency data from SEMEX. For their Holstein bulls with above average methane efficiency scores, we could not identify any clear relationship between this trait and the other traits. However, this is only for one breed of cattle from one company.

  1. Case study: New Zealand
  2. Research in New Zealand genotyped low emitting sheep which identified traits that lead to reduced methane emission. The research found no negative impacts on physiology, productivity and health when selecting for reduced emissions.

Our research highlighted the importance of selecting for feed efficiency. Despite this trait having a lower methane reduction potential than others, it will benefit farmers through more efficient use of feed through better feed conversion (Stakeholder comment, 2023).

Table 6 presents the traits that were selected for further analysis, including quantification and the technologies used to detect or select them. Only a few of the traits found in our review were taken forward because some of the traits did not have robust emission reduction values, so were therefore excluded from our calculations.

Table 5. Traits included in breeding indexes around the world, split by sector and type.

 

Production – offspring

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Calving ease

Carcass conformation

Carcass weight (kg)

Cow calving interval

Fertility

Longevity (years)[3]

Maternal weaning weight

Offspring carcass conformation

Offspring carcass fat

Offspring carcass weight

Offspring feed intake

Offspring survival

Energy corrected milk

Lambing percentage[4]

Maternal instinct

Beef

x

x

x

x

x

x

x

x

x

x

x

x

   

Dairy

x

x

x

x

x

x

x

x

x

x

x

x

x

  

Sheep

     

x

     

x

 

x

x

 

Production – product

 

 

 

 

 

 

 

 

 

    
 

Mature weight

Feed efficiency[5]

Growth rate[6]

Heifer live weight

Body condition score

Heat tolerance

Milk fat + protein

Milk yield

Production efficiency[7]

Residual feed intake

Fleece weight

    

Beef

x

x

x

x

           

Dairy

 

x

  

x

x

x

x

x

x

     

Sheep

x

x

x

 

x

     

x

    
 

Functional

           

 

Cow health

Disease resistance

Microbiome

           

Beef

x

x

x

           

Dairy

x

x

x

           

Sheep

 

 

 

           
 

Climate

 

 

           
 

Methane efficiency2,[8]

Methane intensity[9]

Methane production

           

Beef

 

 

 

           

Dairy

x

x

x

           

Sheep

 

x

x

           

Table 6. The quantifiable traits in each sector, with the technologies which can be used to detect or select them.

Technologies used to detect or select traits

 

 

Quantifiable traits in each sector

Beef

Dairy

Sheep

Feed efficiency

Offspring carcass weight

Methane production

Feed efficiency

Milk fat and protein

Milk yield

Methane intensity

Feed efficiency

Methane yield

Detection methods

Respiration chambers

  

X

   

X

 

X

Sniffers

  

X

   

X

 

X

SF6 tracer gas

  

X

   

X

 

X

Automated head chamber system

  

X

   

X

 

X

Mid-Infrared (MIR) data (proxy)

  

X

 

X

 

X

 

X

PAC

  

X

   

X

 

X

Handheld lasers

  

X

   

X

 

X

Rumen microbial composition

  

X

   

X

 

X

Feed efficiency index

X

  

X

   

X

 

Data management

Selection index theory

X

X

X

X

X

X

X

X

X

National breeding programmes

X

X

X

X

X

X

X

X

X

Multi-country database

X

X

X

X

X

X

X

X

X

Efficient Dairy Genome Project

   

X

X

X

X

  

Ram Compare

       

X

X

Bull catalogues

X

X

X

X

X

X

X

  

Reproductive technologies

Artificial Insemination (AI)

X

X

X

X

X

X

X

  

Conventional breeding

 

X

  

X

X

   

Animal genomics

Microbiome-driven breeding

X

 

X

X

  

X

X

X

Genomic breeding values (GEBVs)

X

X

X

X

X

X

X

X

X

Estimated Breeding values (EBVs)

X

X

X

X

X

X

X

X

X

Genotyping

X

X

X

X

X

X

X

X

X

Genetic markers

X

X

X

X

X

X

X

X

X

Quantifying the potential emission savings

We calculated the potential methane emission reductions under different traits for dairy, beef and sheep. Further information can be found in Appendix E.

The traits identified in our review (see Section 4.2) were further evaluated to assess their applicability to emission reduction calculations, based on requirements for defined quantification of methane emission values (either absolute or relative) and values to have a comparative emission baseline. A summary of the applicable traits used in the quantification calculations are presented in Table 7 below, with further information presented in Appendix E, Section 10.6.4.

Table 7. Traits used in the calculations of emissions savings

Sector

Trait Category

Trait Name

Unit of baseline

Value of methane reduction from baseline

Beef

Production

Feed efficiency

kg CO2e/kg product

7%

Offspring carcass weight

kgCO2e/per kg meat per breeding cow per year

1.3%

Climate

Methane yield

gCH4/kgDMI per generation

12%

Dairy

Production

Feed efficiency

kg CO2e/kg product

5%

Milk fat + protein

MJ CH4/kg milk

12%

Milk yield

kg CH4/kg milk

15%

Climate

Methane intensity

kg CH4/kg milk

24%

Sheep

Production

Feed efficiency

kg CO2e/kg product

7%

Climate

Methane yield

g CH4/kg DMI

35%

The current uptake of genetic traits focused on methane emissions is estimated based on our review and discussions with Scottish Government. This was based on an understanding on the currently uptake of AI and breeding technologies used within the sector from expert knowledge and limited research able to be found online. This rate provides a baseline for the quantification of additional uptake in 2030 and 2045 under four scenarios (further described in Appendix E, Section 10.6.4). The scenarios include: no additional intervention, voluntary uptake, supplier demand and policy changes. Scenario uptake percentages are presented with the current baselines in Table 8 below. These values were developed based on technical expertise and discussion with both stakeholders and Scottish Government, as well as published research. The impact of other traits (such as functional, health related traits) could not be estimated in this work as relevant values for methane reduction potential could not be identified in the literature. Further information in the calculation methodology, including additional detail on the selected scenarios, traits selected and limitations to the data is presented in Appendix E, Section 10.6.

Table 8. Scenario implementation values for dairy, beef and sheep

Type

Scenario

Current baseline

2030 uptake

2045 uptake

Dairy

1. No intervention

75%

80%

80%

2. Voluntary uptake

75%

80%

85%

3. Supplier demand

75%

82.5%

92.5%

4. Policy changes

75%

85%

100%

Beef

1. No intervention

40%

45%

45%

2. Voluntary uptake

40%

45%

50%

3. Supplier demand

40%

47.5%

65%

4. Policy changes

40%

50%

80%

Sheep

1. No intervention

10%

15%

15%

2. Voluntary uptake

10%

15%

20%

3. Supplier demand

10%

17.5%

40%

4. Policy changes

10%

20%

60%

Baseline enteric fermentation methane emissions for beef, dairy cattle and sheep in Scotland in 2021 (totalling 4,020 kt CO2e ), show beef cattle emitted the most at 59% (2,370 kt CO2e ), sheep emitted 26% (1,061 kt CO2e ), and dairy cattle 15% of (590 kt CO2e).

Our calculations found that methane focused traits (methane production/intensity/yield) presented the highest emission reductions for all livestock categories. As the impact of the interaction between traits are unknown, reductions from traits focused on feed efficiency, offspring carcass weight (beef specific) and milk yield, milk fat and protein (dairy specific) are not presented in the maximum reduction potential. However, we acknowledge that reductions for these traits were found within the three livestock categories. Results are presented in Figure 1, Figure 2 and Figure 3 below. These figures show that in each sector, up to 2030, the reductions are relatively steady, but there is a greater reduction at 2045, influenced by the proposed increase in uptake. Due to the proposed uptake percentages the policy change scenario presents the greatest reduction under all traits, with the no intervention scenario showing the smallest reduction due to a 5% increase in uptake in 2030 and no further uptake in 2045.

In the policy change scenario, choosing climate traits, we estimate that emissions would reduce in 2045 up to 382.2 kt CO2e or 9.5% of enteric methane emissions. This includes a 6.8% reduction from beef cattle (161.1 kt CO2e), 6% in dairy cattle (35.4 kt CO2e) and 17.5% in sheep (185.6 kt CO2e). Smaller reductions are feasible from traits focused on feed efficiency, offspring carcass weight (beef specific) and milk yield, milk fat and protein (dairy specific). Further details presented in Appendix E.

Figure 1. Methane emissions for beef cattle traits against the 2021 baseline enteric methane emissions of beef cattle in Scotland. Please note the y-axes do not start at zero to allow for greater visibility of results.

Figure 2. Methane emissions for dairy traits against the 2021 baseline enteric emissions of dairy cattle in Scotland. Please note the y-axes do not start at zero to allow for greater visibility of results.

Figure 3. Methane emissions for sheep traits against the 2021 baseline enteric emissions of sheep in Scotland. Please note the y-axes do not start at zero to allow for greater visibility of results.

Identifying policy drivers and behaviour change needs

This section examines actions to encourage behaviour change. We understand that behaviour change is needed by four stakeholder groups:

  1. Government, which would be policy drivers
  2. Post-farm gate market, such as supermarkets, wholesalers, caterers, hospitality etc
  3. Pre-farm gate, such as livestock markets, breed societies
  4. Farmers

We explored how actions taken by each stakeholder group can enable further behaviour change in the other groups, and present three national level case studies to show actions that promote breeding practices to reduce methane emissions. Examples from these case studies are dispersed through the report in text boxes where the surrounding information was relevant. The countries are as follows:

  • Ireland, which has incentivised and subsidised breeding practices.
  • Canada, which has incentivised and subsidised breeding practices.
  • New Zealand, which has started to take a regulatory approach and has incentivised breeding practices.

All three countries have strong research programmes supporting their policies.

Government action

Scottish Government have an important role in supporting uptake of new breeding techniques through policy. Below are policy drivers that can influence behaviour changes across the other stakeholder groups (post-farm gate market, pre-farm gate actors and farmers).

Legislation and targets

  1. Setting a legal target for methane reduction in Scotland can help to shift the focus of the agricultural industry to methane emissions and align with climate commitments that have been made, such as the Global Methane Pledge at COP26. Other countries have set separate targets for biogenic methane, nitrous oxide, and carbon dioxide, such as New Zealand.
  2. Case study: New Zealand
  3. New Zealand aims to achieve net-zero emissions by 2050 and has a target to reduce biogenic methane by 10% relative to 2017 levels by 2030 and 24 – 47% by 2050. This ‘split-gas’ approach helped focus policy development and action, informed by strong research programmes and stakeholder dialogue. A split-gas approach can also give farmers flexibility to determine the most efficient, cost-effective mitigation practices for their farms (Stakeholder comment, 2023).
  4. A methane target for Scotland could encourage constructive conversations among stakeholders about how to reduce emissions, leading to a higher uptake of relevant practices.

Financial incentives

The concept of breeding livestock for reduced methane emissions may be new for many farmers in Scotland. Methane emissions from ruminant livestock are viewed by many as a natural part of livestock farming, particularly in upland farming systems (Bruce, 2013). Therefore, the economic benefits of breeding for reduced methane emissions will need to be clearly demonstrated to farmers.

Cost was mentioned by some stakeholders as a barrier to selecting livestock based on lower emissions. However, there was little understanding of what the specific costs are. Given this, the perceived cost of adopting new breeding techniques might become just as significant as the barrier of cost itself. However, measuring methane from individual animals in a herd using the technologies in Table 1 is labour intensive and not widely available, which creates financial and labour bottlenecks (CIEL, 2023).

6.1.2.1 Subsidies

Some stakeholders believe that new policies could drive financial incentives (Stakeholder comment, 2023). For example, payments for using the technologies presented in section 4.1.

  1. Case study: Ireland
  2. In Ireland, the Beef Data and Genomics Programme (BDGP) provided payments to suckler beef farmers to improve the genetic merit and GHG emissions of their herd through data collection and genotyping. It was succeeded by the Suckler Carbon Efficiency Programme.
6.1.2.2. Specific funds incentivising measuring emissions

New Zealand supported a programme via funding to enable every stud ram breeder to use PAC chambers to measure emissions. This service was oversubscribed in 2023, indicating that the adoption of measurement techniques could be encouraged by government funding.

  1. Case study: New Zealand

The Cool Sheep™ Programme, launched in 2022, is a three-year programme aiming to offer genetic selection to every sheep farmer in New Zealand to reduce GHG emissions. It gathers phenotype data to provide a methane breeding value which will be available on NProve. Breeders wanting to produce low-methane rams can measure a proportion of their flock using a PAC.

6.1.2.3. Research

All three case study countries have strong Government funded research programmes. The outputs from these informs the policies and actions designed to reduce emissions. Scotland is at the forefront of research on breeding livestock for reduced methane, so this just emphasises the importance of focussing research in this area.

  1. Case study: Canada
  2. Canada’s Agricultural Methane Reduction Challenge will award up to $12 million CD$ to innovators designing practices, processes, and technologies to reduce enteric methane emissions.

Education and advice

Effective communication around breeding for reduced methane and the climate benefits for reducing methane are essential to support uptake. Farmers are crucial stakeholders and while some may be confident in trialling new approaches, advice must be available to help all understand why and how to implement innovative techniques on their farm, manage their farm in a new system and where to ask for help (Stakeholder comment, 2023). Training could also be provided by the private sector.

  1. Case study: New Zealand
  2. The Pastoral Greenhouse Gas Research Consortium (PGgRc) published a series of factsheets to increase understanding of methane research.

Peer to peer learning is very successful as it provides an informal opportunity to ask practical questions of farmers who have already tried and hopefully succeeded.

  1. Example: Northern Ireland farmers visit Scotland

As part of the Farm Innovation Visits, a group of dairy farmers from Northern Ireland visited farms in Scotland to see breeding technologies in practice, such as genetic reports and use of sexed semen.

Farm advisers would be essential to ensure consistent and clear messaging to farmers. Training and communication material could be provided for advisers through existing Government schemes such as the Scottish Farm Advisory Service.

Consumers should be made aware of the importance of reducing methane emissions and of the industry’s associated actions .

Behaviour change

Table 10 shows the outcome of our review on possible Government actions that could lead to behaviour change among farmers, the post-farm gate market and pre-farm gate actors. The three key actions we identified are 1) legislative targets for methane reductions, 2) financial incentives and 3) education and advice programmes.

Table 107: Behaviour changes caused by actions taken by Government

Government actions

Behaviour changes due to Government actions

Farmers

Pre-farm gate actors

Post-farm gate market

Legislative targets for methane emissions reductions

Provides a legislative backstop that must be met. Increased awareness of emissions helps farmers to visualise their emissions and select practices for adoption.

Provides a legislative backstop that must be met. Livestock markets and breed societies prompted to support farmers by providing information on emissions from animals.

Provides a legislative backstop, therefore retailers may encourage suppliers to take on low-emission breeding practices.

Financial incentives

Farmers are more likely to invest time and money in adopting breeding practices if they receive payments for their efforts or if (real and perceived) financial barriers are reduced.

Stronger demand from farmers to understand emissions from livestock will drive breed societies and markets to provide information about emissions.

If breed societies provide advice on reducing emissions from a herd, they could gain a competitive and possibly over time cultural advantage.

Reduced emission livestock products could be marketed for a higher price, aimed at more environmentally conscious consumers.

Risk: if government subsidies were already supporting farmers adopting emission reduction practices, retailers may be less incentivised to pay a premium price.

Education and advice programmes

Increased awareness and clarity on breeding practices to reduce emissions may encourage increased uptake.

Advisers will be able to influence farmers.

Increased awareness of low emissions products may influence consumers to buy food produced using low emission breeding strategies.

Risk: consumers will ask for one thing but often pay for something different

Post-farm gate market

The post-farm gate market includes supermarkets, farm shops, other retailers, consumers and food chain assurance schemes. It has an important role in supporting uptake of new breeding techniques through demonstrating demand and providing price signals. Using our review, we explored actions where the market can influence behaviour change across the other stakeholder groups.

Price signals

Stakeholders discussed the important role of supermarkets, retailers, hospitality businesses, and their suppliers and consumers as these groups can set standards for better prices or to meet customer/societal demands. For example, Tesco aims to be net zero from farm to fork by 2050 , Waitrose has committed to source only from net zero carbon farms in the UK by 2035, and Morrisons aim to be supplied by ‘Net Zero’ carbon British farms as a whole by 2030. Others along the supply chain may need to start to provide evidence of emission reductions as these different retailers and suppliers reduce their Scope 3 emissions, for example as outlined in the British Retail Consortium’s Net Zero Roadmap for the Retail Industry.

Validation of the claims through assurance schemes are important to ensure trust in the food chain. A stakeholder said, “if you take an animal to a ‘normal’ livestock market and claim it has reduced methane emissions, you’ll probably get the same price as any other animal regardless of the additional effort”.

Consumer demand

Consumers paying a premium price are likely to drive new practice adoption. Transparent communication about low emission breeding practices, supply chains and actions on farm is important to demonstrate to consumers the benefits of their choices and reduce the risk of ‘greenwashing’.

  1. International example: Sweden
  2. In 2022, methane-reduced beef was sold in Sweden. It was well received by consumers, selling out in less than a week. There was however backlash in the media with claims of greenwashing. This example emphasises consumers’ interests in climate-friendly options. while ensuring transparency.

Behaviour change

How the market influences other stakeholders is explored in more detail in Table 10. The key actions are 1) improved price signals from retailers and 2) increased consumer demand which is realised at the sales point.

Table 11: Behaviour changes caused by post-farm gate market actions

Post-farm gate actions

 

Behaviour changes as a result of post-farm gate actions

Government

Farmers

Pre-farm gate industry

Post-farm gate market retailers

Price signals from retailers

 

Similar to government financial incentives, farmers are more likely to invest time and money in adopting breeding practices if they receive payments for their efforts.

Risk: uptake by farmers could be inconsistent depending on which retailers adopt this action first.

Livestock markets or breed societies could display methane scores if they know this is something that farmers are looking for.

Retailers offering a premium for low-emitting products will encourage uptake of practices.

Marketing low-emitting products will raise awareness among consumers, possibly increasing demand for low-emission products.

Post farm gate actors own emission reduction targets to meet societal demand for low emission products will require farms to reduce emissions

Increased consumer demand for low emissions livestock products

Government may be encouraged to support low methane emissions breeding practices due to a higher demand.

Procurement guidelines for catering in Government funded facilities could include low methane emitting meat.

Increased demand for low emissions products may prompt adoption of practices.

Due to farming in Scotland not being solely driven by the market, consumer demand alone may not influence the pre-farm gate industry. Yet it may lead to actions that prompt further actions related to emission savings.

Increased demand for low-emission products will incentivise retailers and hospitality to provide these, possibly paying a premium to farmers.

Pre-farm gate actors

Pre-farm gate actors refers to industry representatives, levy groups, research institutions, breed societies, and livestock markets. They have an important role in supporting uptake of new techniques through increasing understanding and supporting data collection. Below are actions that can influence behaviour change.

Improving data and data sharing

A key infrastructure need is an accessible database of genetic information, including methane emissions, to enable benchmarking (Stakeholder comment, 2023). Stakeholders noted that farmers may struggle to envision new practices on their farms, and a database can help to conceptualise the traits.

Case study: New Zealand

The ram selection tool nProve provides a user-friendly platform to select required traits in a ram, including methane production.

Existing platforms already used by farmers, such as ScotEID, the Beef Efficiency Scheme (BES), and SRUC’s genetic tool EGENES could add new elements around methane (Stakeholder comment, 2023). For example, Nprove allows farmers to assess methane elements in a user-friendly way.

The Beef Efficiency Scheme (BES) required farmers and land managers to submit tissue samples and other metrics of their beef herd to develop an understanding of the genes within the herd to improve efficiency. Uptake from the industry was low, with only 30% of the national breeding herd participating in the scheme. It currently remains unclear in the literature if the captured data has been incorporated into any local breeding schemes or progressed following the end of the scheme. This scheme could provide valuable learning on the integration of positive genetic traits across the herd in Scotland.

In our review, a stakeholder commented that as only a handful of breeds make up most of the livestock sector in Scotland, the establishment of a database would not take long to create (Stakeholder comment, 2023). This comment however shows the lack of understanding that the genetic material for breeding for methane is independent of breed and based on individual animals.

Case study: Ireland

The Irish Cattle Breeding Federation (ICBF) launched the National Genotyping Programme (NGP) in 2023 to achieve a fully genotyped cattle herd in Ireland. The programme offers beef and dairy farmers a low-cost option to collect DNA samples from calves at birth. The collected information is used to identify specific traits which contribute to national genetic indexes, including methane traits. It also allows farmers to optimise the health and productivity of their herd, while reducing the emissions intensity. The ICBF further publish methane evaluations for AI sires when methane data has been recorded.

Ireland’s NGP and New Zealand’s N Prove provide examples of the development of national databases. In Ireland, the use of metrics like Residual Methane Emissions (RME) index and predicted transmitting ability (PTA) aim to provide an easy way of comparing livestock to the average and to other farmers. Stakeholders noted that a challenge in the Scottish context could be a reluctance by stakeholders to pool data. However this has been successfully achieved in the Scottish pig industry with a number of health and productivity benefits to the individual farmers and to the sector. The NGP also allowed for subsidising DNA sampling of calves which helps to genotype the national herd

Stakeholders discussed the potential for livestock markets to display information on methane emissions. In many markets, a screen displays the weight of the animal and the name of the seller; it could be possible to add the expected or benchmarked methane emissions.

Case study: New Zealand

A methane breeding value was launched in 2019 by Beef and Lamb New Zealand, giving the sector a practical decision making tool. This led to the development of The Cool Sheep™ Programme (see section 6.1.2).

Metrics for methane emissions

Stakeholders recommend adding methane as an estimated breeding value (EBV) as this would allow farmers to benchmark. Stakeholders emphasised that metrics would only be used if they are adopted consistently across Scotland (and perhaps the UK) with cross sector collaboration and there was some incentive for farmers to reduce methane emissions from their livestock. Similarly, to the adoption of RME and PTA figures in Ireland, regulation and guidance from Scottish Government would be advisable to make sure the most sensible metric was adopted.

Case study: Ireland

Residual methane emissions (RME) index is a metric to understanding the difference between the expected methane emissions based on feed intake and the actual emissions. High RME is undesirable and low RME is desirable.

ICBF methane predicted transmitting ability (PTA) values have been produced by recording methane emissions from over 1,500 animals from 19 breeds. These are publicly available for AI beef and dairy bulls. Bulls are classed as favourable or unfavourable compared with the average sire.

Behaviour change

  1. The two key take-aways from our review are 1) improved data and data sharing amongst farmers, researchers and across stakeholders and 2) developing metrics for methane emissions to enable benchmarking between farmers and products. Table 12 describes how actions by pre-farm gate actors could support behaviour change among other stakeholders.

Table 12: Behaviour change due to actions taken by the pre-farm gate actors

Pre-farm gate action

Behaviour change due to pre-farm gate action

Government

Farmers

Pre-farm gate actors

Post-farm gate market

Improved data and data sharing

A database can inform policy.

Enables farmers to understand the emission reduction potential of their animals.

Displaying methane information at markets can help choose livestock based on emissions.

More data would support more robust research, thereby increasing the output of Scotland-specific research.

Markets around Scotland displaying methane data would raise awareness among farmers.

Better data would enable retailers to communicate sustainability data to customers, increasing trust in the food system.

 

Metrics for methane emissions

Scottish Government could ensure all relevant stakeholders are involved in developing a metric.

Metrics would enable farmers to make comparisons against individual animals when deciding which ones to breed or purchase.

Breed societies and livestock markets would be able to display methane emissions.

Breed society representatives can discuss options for reducing emissions.

Retailers have a consistent metric they can use to communicate the methane emissions of products to consumers.

Farmers

Farmer behaviour change in this context relates to choosing animals with low methane traits to breed, and implementing systems on farm that support this. Some farmers could measure emissions from their livestock to verify the effectiveness of breeding for reduced emissions. Uptake of technologies outlined in section 4 provides the opportunity to better track genetics and traits in their herd.

Farmers will need support to make these changes and to enable behaviour change from the pre-market, post-market and government stakeholder groups identified in the sections above. In addition, the adoption of new practices will likely vary between dairy, beef and sheep producers, and the challenges they face will be different. Farmers who are already using reproductive technologies, such as sexed semen and AI, are expected to progress fastest in this area, given their familiarity with the processes. It is likely that the dairy sector will lead the way, and to a smaller extent, the beef sector. Rapid uptake of AI (and therefore sexed semen) in the sheep sector faces practical challenges, therefore it may be best to prioritise low-emitting traits in rams.

The financial benefit of farmers selecting methane traits is currently unclear. It is likely that the primary motivation will come from the supply chain; it will be important to have specific supply chain indicators. For example, if a milk buyer sets methane reduction goals, suppliers will need to respond. Behaviour change is also influenced by seeing neighbours or peers taking on new practices for example. Below are some points for each of the different livestock sectors groups that should be considered to enable the behaviour change actions identified in the previous sections.

Cummins et al (2022) advise that further research is needed on how breeding for low methane emissions affects the productive and profitable genes that make an animal appealing to farmers. However, research in New Zealand on genotyped low emitting sheep showed no negative impacts on physiology, productivity and health when selecting for reduced emissions and preliminary economic analysis shows that low-emitting sheep could lead to higher profits, primarily due to higher growth rates, a greater proportion of meat, and increased wool production. This section also briefly covers some actions that could be undertaken on farm to support farmers to shift to breeding lower methane emitting livestock.

Sheep farmers

Sheep farmers deal with a large number of animals which tend to be farmed extensively in Scotland, so using methane detecting technologies is potentially more difficult than for other livestock sectors. Despite this challenge, the shorter time to slaughter means that low-emitting traits can be introduced regularly and methane reductions can accumulate quickly (Stakeholder comment, 2023). In addition, other countries such as New Zealand have implemented programmes to begin to measure the national flock such as The Cool Sheep Programme (see section 6.1.2). Stakeholders discussed how the sheep sector produces a lower-value product compared to the cattle sector, so cash flow may be a prohibiting factor in taking on new practices.

Beef farmers

Stakeholders asserted that the beef sector is complicated by several commercial interests in the market which influence genetic improvement. Unlike the dairy sector, AI is not widely used in the beef sector (Stakeholder comment, 2023). However, there are opportunities to influence the genetics of the herd by encouraging bull breeders or bull stud farms to take on practices to support low-emitting traits.

As it is common for dairy cow offspring to enter the beef system, there is the opportunity to use lower emitting dairy animals to feed into emissions reductions in the beef sector (Stakeholder comment, 2023).

Dairy farmers

The dairy sector is the most advanced ruminant sector in using genetic technology and tools for selective breeding. For example, AI is fairly common practice, currently with the objective of increasing productivity rather than targeting emissions. Progress in the sheep and beef sectors is much slower due to challenges around practicalities, sufficient data and uptake of technologies in these sectors. The dairy industry also has a steadier cashflow than beef and sheep (Stakeholder comment, 2023), and is more progressive when it comes to real-time data collection and data management. This puts the dairy sector in a good position to advance breeding for reduced methane emissions.

Cross-farm actions to support breeding lower methane livestock

Strong and structured communication, sharing of ideas and engagement locally are important drivers to enable behaviour change in farming communities. Peer to peer support, for example through breeding groups, to share ideas, showcase technologies and discuss successful and disappointing technologies will enable neighbours and other local farmers to progress faster. Organising local workshops, either by Government supported advisers or leading farmers, would help to spread the word about the importance of breeding for reduced emissions and provide practical examples. The more discussion about the overall aim, the need to reduce emissions, the potential actions, outcomes and successes, the more likely that breeding for reduced methane emissions will become mainstream.

Gaps in the research

We identified the following gaps in research:

  • Timeline of availability for the technologies. Due to a lack of robust information in many cases, we made an expert judgement on the availability of the technologies in Scotland up to 2030 and 2045.
  • Quantified impact of introducing methane traits in case study countries. We did not find evidence for the actions and policies introduced in the case study countries reducing overall country emissions. A reason for this is that many of the examples presented in the case studies in the appendices are very recent, therefore there has not been enough time to quantify the emission savings. In addition, it could be challenging to see whether these actions had a specific impact emissions due to other surrounding factors, for example changes in stocking rate, or outbreak in disease.
  • Evidence for current level of uptake in Scotland and the UK. The review did not find much evidence for current levels of uptake of breeding livestock for reduced emissions.
  • Mitigation potentials of some traits. Many sources did not present methane emission values, but instead covered genetic correlations between traits. This meant that due to a lack of data many of the traits identified in the REA (see Table 5) were excluded from quantification. In other cases, some mitigation potentials were not comparative to the baseline used in our study because it presented changes from an entire lifecycle or system.
  • The interaction between traits. Emission calculations were quantified for individual traits, rather than combining the mitigation potential for all traits because the relationship and interaction between traits is unknown.
  • Due to the smaller quantity of literature available on methane efficiency focused traits, the reduction potential values may be less robust. Greater consistency in measurement, modelling, and presentation and their impacts on emissions savings and animal production would fill this knowledge gap.

Conclusions

We estimate that, by 2045, breeding for reduced methane emissions could achieve a reduction in enteric methane emissions of 9.5% from the baseline, including 6.8% reduction from beef, 6% from dairy and 17.5% from sheep assuming livestock numbers remain constant. This would be achieved by selecting breeding traits for methane efficiency (methane production, intensity and yield), feed efficiency, offspring carcass weight, milk yield and milk fat and protein. Selecting for these traits brings cumulative and permanent emission savings. A limited number of studies researched the impacts of selecting low-methane traits on productivity and health and found that these qualities were not compromised.

Scotland has a well-developed research base around breeding livestock for reduced methane emissions, placing it in good stead in developing further work and providing validation and trust. Research programmes in New Zealand, Canada and Ireland have successfully interacted with farmers, for example, by the development of user-friendly, accessible tools. Our stakeholder comments implies that a comparable interaction between research and on-farm activities and innovation is currently lacking in Scotland.

To achieve the emissions reductions, actions and behaviour change will be required by four stakeholder groups: Scottish Government, pre- and post-farm gate industry and markets, and farmers. Change will need to be co-created across the stakeholder groups.

The financial benefit of farmers selecting methane traits remains uncertain. Therefore, it is likely that the primary motivation will be the supply chain which will need supply chain indicators. For example, if a milk buyer sets methane reduction goals, suppliers will need to respond. Behaviour change is also influenced by neighbours or peers taking on new practices.

The key barriers to uptake are around knowledge and perceived cost. To alleviate these, Government funding could be targeted towards more data collection and research with farmer involvement to improves robustness. Investment in adviser training and farmer peer-to-peer will enable local farmers to progress faster. Organising local workshops, either by Government supported advisers or leading farmers, would help to spread the word about the importance of breeding for reduced emissions and provide practical examples. The more discussion about the overall aim, the actions, outcomes and successes, the more likely it is that breeding for reduced methane emissions will become mainstream.

The technologies we estimate could be mainstream by 2030 include a national breeding programme, sexed semen, artificial insemination (AI) and estimated breeding values (EBVs). However, their success will be about but the interactions between them. For example, data will inform EVBs, which in turn will inform a national breeding programme. If the constant use of methane detecting technologies is required, this may be difficult to implement in extensive farming systems. However, if a proxy measurement was used or the breeding stock was known to provide the necessary traits, this would allow existing systems to continue.

On this basis, we think there is a strong foundation for breeding for reduced emissions to become part of Scottish Government’s commitments.

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Quinton, C.D., Hely, F.S., Amer, P.R., Byrne, T.J. and Cromie, A.R., 2018. Prediction of effects of beef selection indexes on greenhouse gas emissions. Animal, 12(5), pp.889-897.

Reid, A. and Wainwright, W., 2018. Climate Change and Agriculture: How Can Scottish Agriculture Contribute to Climate Change Targets.

Rowe, S.J., Hickey, S.M., Johnson, P.L., Bilton, T.P., Jonker, A., Bain, W., Veenvliet, B., Pilel, G., Bryson, B. and Knowler, K., 2021. The contribution animal breeding can make to industry carbon neutrality goals. In Proc. Assoc. Advmt. Anim. Breed. Genet (Vol. 24, pp. 15-18).

Rowe, S.J., Hess, M., Zetouni, L., Hickey, S., Brauning, R., Henry, H., Flay, H., Budel, J., Bryson, B., Janssen, P. and Jonker, A., 2020. Breeding low emitting ruminants: predicting methane from microbes. Multidisciplinary Digital Publishing Institute Proceedings, 36(1), p.177.

Scholtens, M., Lopez-Villalobos, N., Lehnert, K., Snell, R., Garrick, D. and Blair, H.T., 2020. Advantage of including genomic information to predict breeding values for lactation yields of milk, fat, and protein or somatic cell score in a New Zealand dairy goat herd. Animals, 11(1), p.24.

ScotEID, n.d. Beef Efficiency Scheme. Available from: https://www.scoteid.com/bes

Scottish Government, 2023. Climate Change. Available from: https://www.gov.scot/policies/climate-change/reducing-emissions/

 

Scottish Government, 2022. Gene editing. Available from: https://www.gov.scot/binaries/content/documents/govscot/publications/foi-eir-release/2023/12/national-farmers-union-of-scotland-and-gene-editing-eir-release/documents/202200280877—item-01—feb-2022/202200280877—item-01—feb-2022/govscot%3Adocument/202200280877%2B-%2BItem%2B01%2B-%2BFeb%2B2022.pdf

Scottish Government, 2020. Securing a green recovery on a path to net zero: climate change plan 2018–2032 – update. Available from: https://www.gov.scot/publications/securing-green-recovery-path-net-zero-update-climate-change-plan-20182032/pages/13/

Semex, 2023. Semex & methane efficiency. Available from: https://www.semex.com/fi/i?lang=en&page=methane

Semex, 2023. Catalogue. Available from: https://www.semex.com/uk/i?lang=en&view=list&breed=HO&data=tpi

Sorg, D., 2021. Measuring livestock CH4 emissions with the laser methane detector: A review. Methane, 1(1), pp.38-57.

SRUC, 2020. GreenCow. Available from: https://www.sruc.ac.uk/research/research-facilities/beef-sheep-research-facility/beef-sheep-research-projects/greencow/

SRUC, 2023. EGENES. Available from: https://www.sruc.ac.uk/research/research-areas/genetics-genomics/#EGENES

Stout, D. 2021. Using Estimated Breeding Values (EBVs) in Sheep – TECHNICAL NOTE TN755. SAC Consulting.

TEAGASC, 2022. Strategies to reduce methane emissions from Irish beef production. Available from: https://www.teagasc.ie/animals/beef/grange/beef2022-open-day/strategies-to-reduce-methane-emissions-/

Tedeschi, L.O., Abdalla, A.L., Álvarez, C., Anuga, S.W., Arango, J., Beauchemin, K.A., Becquet, P., Berndt, A., Burns, R., De Camillis, C. and Chará, J., 2022. Quantification of methane emitted by ruminants: a review of methods. Journal of Animal Science, 100(7), p.skac197.

Tesco, 2021. Certifications. Available from: https://www.tescoplc.com/sustainability/certifications

Tesco, 2023. Sustainability. Available from: https://www.tescoplc.com/sustainability/

UK Parliament, 2023. Genetic Technology (Precision Breeding) Bill 2022-23. Available from: https://commonslibrary.parliament.uk/research-briefings/cbp-9557/

UK Research and Innovation, 2022. Where livestock agriculture fits in a net zero future. Available from: https://www.ukri.org/who-we-are/how-we-are-doing/research-outcomes-and-impact/bbsrc/where-livestock-agriculture-fits-in-a-net-zero-future/#:~:text=Cattle%20breeders%20can%20now%20use,immediate%20fall%20in%20methane%20emissions.

van Breukelen, A.E., Aldridge, M.N., Veerkamp, R.F., Koning, L., Sebek, L.B. and de Haas, Y., 2023. Heritability and genetic correlations between enteric methane production and concentration recorded by GreenFeed and sniffers on dairy cows. Journal of Dairy Science106(6), pp.4121-4132.

van Staaveren, N., Oliveira, H.R., Houlahan, K., Chud, T.C., Oliveira Jr, G.A., Hailemariam, D., Kistemaker, G., Miglior, F., Plastow, G., Schenkel, F.S. and Cerri, R., 2023. The Resilient Dairy Genome Project–a general overview of methods and objectives related to feed efficiency and methane emissions. Journal of dairy science.

Wellmann, R., 2023. Selection index theory for populations under directional and stabilizing selection. Genetics Selection Evolution, 55(1), p.10.

Worden, D. and Hailu, G., 2020. Do genomic innovations enable an economic and environmental win-win in dairy production?. Agricultural Systems, 181, p.102807.

Appendix / Appendices

Technologies involved in breeding for reduced methane, full tables

Table 13. Examples of the detection methods involved in the process of breeding livestock for reduced methane emissions.

 

Description

Sector

Data collected

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M),

Future possibility (FP), Not applicable (NA)

Practical considerations in Scotland

Beef

Dairy

Sheep

 

Respiration chamber

A sealed chamber taking samples from an animal in a controlled environment. The animal is typically kept in the measurement chamber for a couple of days and is provided with food and water (Zaman et al., 2021).

All

Methane concentration

Believed to be the most accurate way to measure methane from livestock (Zaman et al., 2021).

Measurements taken over several days increases robustness (Manzanilla-Pech et al., 2021).

Restricts normal animal behaviour and movement (Zaman et al., 2021; Manzanilla-Pech et al., 2021).

High capital cost.

Limited to a few or one animal per chamber (Manzanilla-Pech et al., 2021).

2030: E

2045: E

2030: E

2045: E

2030: E

2045: E

Used in research facilities in Scotland, however there is limited scope to use them on farms due to the high cost (Stakeholder comment, 2023).

Sniffers

Non-dispersive infrared unit that can be installed in feeding areas or milking parlours (van Breukelen, 2023; de Haas et al., 2021).

All

Methane and CO2 concentration

Non-invasive, can be incorporated into existing milking technologies (de Haas et al., 2021).

Offers large scale recording (de Haas et al., 2021).

A spot measurement, not a true reflection of emissions per day.

Limited to indoor measuring (Cummins et al., 2022).

More difficult to introduce in beef and sheep sectors compared to dairy due to frequent milking.

2030: FP

2045: FP

2030: E

2045: E

2030: FP

2045: FP

In 2021 ‘the first’ was installed at a Dutch dairy farm for research (CRV, 2021). No evidence found for use on farms in the UK.

SF6 tracer gas

A tube containing sulfur hexafluoride (SF6) tracer gas is placed inside the rumen and collection lines are used to collect breath samples (Cummins etal., 2022).

All

Methane concentrations

Measurements can be taken from confined, free range, and grazing animals (Manzanilla-Pech et al., 2021).

Invasive measure which has animal welfare concerns (de Haas et al., 2021).

SF6 is a greenhouse gas itself (Tedeschi et al., 2022).

Daily canister collection means high labour (Cummins etal., 2022).

2030: E

2045: E

2030: E

2045: E

2030: E

2045: E

No evidence was found for use in UK trials and research, but it used widely in globally. It would be beneficial in Scottish research due to measuring livestock while grazing.

Automated head chamber system (e.g. GreenFeed)

A transportable head chamber unit that can be positioned in housing or pasture. Feed is used to attract livestock to the unit (van Breukelen, 2023; Zaman et al., 2021).

All

Methane and CO2 concentrations

Non-invasive.

It can be set up in grazing fields or in housing.

High purchase and running costs.

A spot measurement, not a true reflection of emissions per day.

Feed to attract livestock increases costs.

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

No evidence was found for use in UK trials and research. However it is potentially a feasible option for Scotland due to the benefits of transportability and measuring grazing livestock.

Mid-Infrared (MIR) data

MIR spectroscopy is used to predict the fat and protein content of milk. As methane is linked to milk composition, it can be used as a proxy to predict methane emissions (Dehareng et al., 2012; Semex, 2023)

Dairy

Milk component such as lactose, protein and fat

MIR technology is already used in milk recording, so could provide an existing infrastructure to integrate methane reporting into.

Because it is a proxy, validation of results (for example with a respiration chamber) is required (Denninger et al., 2020).

NA

2030: I

2045: I

NA

No evidence found of MIR being used in the UK to estimate methane, but European examples were found. As data could become available through existing milk recording schemes, it could be introduced by innovators by 2030. If the need for verifying results via detection methods is removed, this could be mainstream by 2045.

Portable accumulation chambers (PAC)

A portable respiration chamber which takes measurements over a short period of time (e.g. 1 hour) (Cummins et al., 2022).

All

Methane and CO2 concentrations

Quick measurement period reduces animal stress (Cummins et al., 2022).

Transportable (NZHerald, 2023).

Feeding and management protocols must be followed prior to measurements (Duthie et al., 2024).

Not suitable for long-term measurements (Cummins et al., 2022).

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

A promising option for Scotland, given its transportable between farms. SRUC recently acquired a PAC for sheep in the UK. However current research needs to be completed before they can be used widely (Duthie et al., 2024).

Handheld lasers

A handheld device originally developed to detect gas leaks can measure concentrations of methane in livestock breath (Sorg, 2021).

All

Methane concentrations

Non-invasive and portable.

Can take measurements from grazing livestock.

Can take measurements from several animals in one day.

Results can be sent to a smart phone (Sorg, 2021)

Has a lower accuracy, measurements are highly affected by environmental conditions (de Haas et al., 2021; Sorg, 2021)

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

No evidence found for use in UK research. However, the benefit of taking measurements from several animals in the same day may make it an attractive option for Scotland. Its widespread use may depend on supporting infrastructure such as reporting systems.

Rumen microbial composition

The rumen holds a variety of microorganisms that aid in the digestion of feed. By studying the microbes present in the rumen, those influencing the production of methane can be identified and used as a proxy to identify animals with the microbiome composition which emits lower methane (Miller et al., 2023).

All

Dry matter intake and methane concentrations

It can also be used to improve feed conversion and disease resistance (Duthie et al., 2024).

The composition of the microbiome is largely influenced by the ratio of feed (i.e. forage vs concentrate) so accuracy of results may be influenced by diet (Miller et al., 2023).

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

A technique being used in Scottish research in all sectors. Likely to remain an experimental technology, with future trials on some farms in the future.

Feed efficiency index

An indicator showing how efficient a cow is at converting feed into product, for example, into milk. Research shows that selecting for feed efficiency reduces methane emissions (Manzanilla-Pech et al., 2022).

Dairy, beef

Feed efficiency,

feed intake + milk yield (dairy) / meat quality (beef)

Helps to reduce the amount of feed required and therefore associated costs.

It’s important that selecting for feed-efficiency does not compromise growth.

2030: M

2045: M

2030: M

2045: M

2030: M

2045: M

No evidence found of this being done with the aim of reducing methane emissions in the UK, but it is used in the UK to improve efficiency in dairy.

Table 14. Examples of data management tools involved in the process of breeding livestock for reduced methane emissions.

 

Description

Sector

Data collected

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M), Future possibility (FP),

Not applicable (NA)

Practical considerations related to the feasibility in Scotland

Beef

Dairy

Sheep

ScotEID

A multispecies database which records and tracks livestock information. It may be possible to build on this in the future to introduce information relevant to methane.

All

Births, deaths and movements.

A familiar platform for farmers in Scotland.

 

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

An established infrastructure exists and is familiar to the industry, therefore a promising option to repurpose to include methane traits.

nProve

A free tool for New Zealand farmers to use to choose rams for breeding. They can choose the terminal or maternal traits that fit their breeding goals. When choosing maternal traits, methane production is an option.

Sheep

Reproduction, lamb growth, size, meat, wool, health indices

Very user friendly, guides the user through the selection process. Contact details are provided for breeders that meet chosen criteria.

Farmers can choose rams based on location, breed and exclude certain flocks from results.

 

NA

NA

2030: FP

2045: I

To be successful in Scotland, genetic evaluation and measuring methane from sheep would need to be common practice. There are existing tools such as ScotEID which records births, deaths and movements, and RamCompare which presents data from performance recorded rams i.e. carcass weight, that could be repackaged to incorporate methane production. But success would also depend on wide use of PAC (as done in New Zealand).

Selection index

Combines information to predict an animals estimated breeding value (EBV). It can be used to select traits for breeding goals, for example, milk production, feed efficiency and health to maximise future profit (Wellmann, 2023; de Haas et al., 2021).

All

 

It is possible to apply weightings to traits in relation to its importance in the breeding goals

Before a trait can be added to a selection index, it needs to be “clearly defined, recordable, affordable, have phenotypic variation, be heritable, and the genetic correlations between other traits in the index need to be known” (de Haas et al., 2021).

2030: E

2045: I

2030: E

2045: I

2030: E

2045: I

In 2023, Semex introduced a methane index for Holsteins in Canada. Availability in Scotland depends on the progress of measuring methane.

National breeding programme

A programme which plans and identifies breeding objectives, traits and information on selection criteria.

All

 

It can optimise gains and trait changes (De Haas et al., 2021).

To be successful at a national scale, significant data and cooperation is required.

For a trait to be included in a programme it must be environmentally important, express genetic variation and be measurable (Teagasc, 2012).

2030: M

2045: M

2030: M

2045: M

2030: M

2045: M

In 2023, The National Sheep Association began a 3-year initiative to measure methane from 13,500 sheep. The aim of this is to measure production traits to incorporate into breeding programmes. With progress like this, it is possible that national breeding programmes will be mainstream by 2030.

Multi-country database

An international database that contains performance/production (trait-related) records from a large number of livestock (Manzanilla-Pech et al., 2021).

All

 

An increased dataset

Improves robustness (Manzanilla-Pech et al., 2021)

Combining data from different countries can be challenging due to differences in reporting and recording, technology, favoured breeds and management style (Van Staaveren e al., 2023).

2030: FP

2045: FP

2030: E

2045: I

2030: FP

2045: FP

A significant amount of collaboration is required to make this effective. Due to having to overcome the data sharing challenges, it is possibly unlikely this will be available with the aim of reducing methane emissions by 2045. There may be some progress in the dairy sector however due to the introduction of the methane index in Canada.

Efficient Dairy Genome Project

An international initiative that combines data from 6 countries (Australia, Canada, Denmark, United Kingdom, United States, and Switzerland) aiming to build one genomic reference population and a unique database of DMI records.

Dairy

DMI, milk, methane was measured in 4 of the 6 countries participating in the initiative

The overall objective is to potentially improve feed efficiency (cost benefit) and reduce methane emissions (environmental benefit).

Combining data from different countries can be challenging due to differences in areas such as reporting and recording, technology, favoured breeds and management style (Van Staaveren e al., 2023).

NA

2030: I

2045: I

NA

 

Bull catalogues (such as Genus Bull search)

This index allows farmers to see the scores of certain traits in bulls. One of these traits is called Feed Advantage which can identify bulls with the greatest feed conversion (ABS, 2023).

Dairy, beef

 

Farmers can choose bulls with the desired characteristics to use in breeding.

 

2030: M

2024: M

2030: M

2024: M

NA

These are already available for farmers to use, so we would estimate them to be mainstream by 2030.

Beef Efficiency Scheme

A 5-year scheme funded by Scottish Government to help improve the efficiency, sustainability and quality of beef herds – helping to increase genetic value and reduce GHG emissions. The scheme focused on cattle genetics and management practices on-farm.

Beef

Tissue samples – genotyping

blood samples,

calving data,

culling/death reasons, dam data (docility)

Funding was provided to farmers for data collection and entry.

A free advisory service was also provided to assist farmers in developing their beef herd.

 

2030: FP

2045: FP

NA

NA

This scheme ended in 2021. It may be possible to build on and repackage the scheme to consider methane traits in the future.

Table 15. Examples of reproductive technologies involved in the process of breeding livestock for reduced methane emissions.

 

Description

Sector

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M)

Future possibility (FP) Not applicable (NA)Practical considerations related to the feasibility in Scotland

 

Beef

Dairy

Sheep

 

Semen freezing

A technique to preserve semen.

All

Provides security in an instance that could risk a breed’s survival (Jones et al., 2020)

Variable success rate using thawed semen.

2030: M

2045: M

2030: M

2045: M

2030: I

2045: I

 

Artificial insemination (AI)

A technique to inseminate females, using fresh or frozen semen.

All

High success rate for cattle.

Not required to have a bull on the farm.

Better guarantee of uniform calving.

To be most efficient, livestock are required to come into heat at the same time as AI takes place. This is done artificially by the farmer, adding additional labour.

AI in sheep is often done laparoscopically, which is a surgical procedure performed by a vet. Due to the scale and extensive nature of sheep farming, this brings practical challenges.

Relies on sufficient infrastructure to collect and store semen of which there are limited facilities in Scotland (in particular for the sheep sector) (Stakeholder comment, 2023).

2030: M

2045: M

2030: M

2045: M

2030: I

2045: I

AI is already common practice in the dairy sector, with some use in the beef sector too. It’s likely this will be mainstream by 2030 for cattle. However, due to the practical challenges in sheep, it may still only apply to innovators.

Sexed semen

A method which allows control over the sex of the offspring by separating sperm cells based on their X or Y chromosome content. By focusing on females for example, there is the potential to reduce methane by reducing the number of unwanted males (Duthie et al., 2024).

All

Increases the selection of females in the dairy sector.

Improves productivity.

Success relies on the uptake of AI.

2030: M

2045: M

2030: M

2045: M

2030: I

2045: I

This is widely practiced in the dairy sector. Use in the beef sector is currently lower, however by 2030 there is the potential for this to be mainstream. Progress is determined by the uptake of AI in the sector. Due to the practical challenges associated with AI, it will likely remain an innovative practice.

In-vitro fertilisation (IVF)

Harvested oocytes are taken from donor cows and fertilised in a petri dish with semen to create an embryo.

Beef, dairy

Less semen required

Nutrition and diet need to be consistent in the lead up to extracting oocytes.

2030: I

M

NA

Process is conducted in a lab under sterile conditions.

Embryo freezing

A method for cryopreservation of embryos for long-term storage or transport. This tends to occur in conjunction with MOET.

All

  

I?

I?

I?

Lack of suitable laboratories

Conventional breeding

The use of bull/ram to cow/ewe breeding. Enhanced tools to select lower than average emitting bulls or rams.

All

Minimal technical input.

Familiar management practice for farmers.

Little control over selecting desirable traits.

It requires waiting for offspring to become fully grown before seeing if they have taken on the desired traits.

M

M

M

 

Table 16. Examples of animal genomics involved in the process of breeding livestock for reduced methane emissions.

 

Description

Sector

Data collected

Benefits

Risks

Timeline of availability in Scotland: Experimental (E), Innovators (I), Mainstream (M), Future possibility (FP), Not applicable (NA)

Practical considerations in Scotland

Beef

Dairy

Sheep

Microbiome-driven breeding

Emphasis is on selecting livestock with a rumen microbiome composition which is more efficient at fermenting of feed so that less excess hydrogen and thus less methane is produced.

Livestock genetics and therefore breeding influences the composition of the microbiome which therefore affects the amount of methane released.

All

Rumen fluid samples – sequencing of microbial DNA

There is a growing demand for livestock that emit less methane.

Potential method for improving animal health and reduce environmental impact.

This is a relatively new field, and much is unknown about how the gut microbiome develops and is maintained over time.

It is unclear how much influence the animal may have over those processes.

2030: E

2045: E

2030: E

2045: E

2030: E

2045: E

Good early signs but still at research stage.

Genomic breeding values (GEBVs)

Values that are based on information from livestock DNA and measured performance. Can be used with EBVs to improve accuracy of breeding programmes. (Meat Promotion Wales. 2013).

All

DNA and performance records

Can be used to identify traits that are difficult to record

Beneficial for traits measured in only one sex

Useful for accurately measuring traits that occur later in life (Scholtens et al., 2020).

Accuracy of the estimate is dependent on the number of animals included in the reference population (Scholtens et al., 2020).

2030: E

2045: I

2030: E

2045: I

2030: E

2045: E

For the UK beef industry, GEBVs are currently available for a number of carcass traits in Limousin cattle (Business Wales, 2016)

Estimated Breeding values (EBVs)

Calculated from the performance data of recorded animals. Environmental factors (e.g. feeding) are filtered out to provide a genetic value for each trait (Stout, D. 2021).

All

Performance records – parentage and traits of interest (e.g. weight traits).

Provides a more objective (data driven approach) towards selection.

Genetic selection based on EBVs leads to faster rates of genetic gain and flock improvement (compared to selection based on raw data or basic observation)

Allows comparisons within breeds, not between breeds.

2030: M

2045: M

2030: M

2045: M

2030: M

2045: M

Use as a tool to aid in the selection of healthy and structurally sound animals.

Genotyping

The process of determining/comparing the genetic variation of DNA sequences (or whole genomes) amongst individuals or populations.

All

 

Aids in genomic selection of both desirable (and harmful) traits.

Prediction accuracy of genomic selection is influenced by the type (male/female, previous generations) and number of animals that are genotyped (Mohammaddiyeh et al., 2023)

NA

NA

NA

Farmers cannot use this method themselves and therefore require the use of external service providers.

Genetic markers

Genetic markers identify desirable traits in animals which can then be selected for breeding (Meat Promotion Wales. 2013).

All

 

DNA marker information can be obtained from animals at birth (Hayes et al., 2013).

Can be used to select for traits that are difficult to record.

Genetic progress in slow given the relatively long generation interval in cattle and sheep

NA

NA

NA

Farmers cannot use this method themselves and therefore require the use of external service providers.

Gene editing

A method for editing individual genes within the genome of a cell, embryo or ovum to bring about a desired genetic change.

All

 

The ability to eliminate undesirable traits.

Accelerates rate of genetic improvement.

Introduces variation into a population e.g. disease resistance

Identifying the appropriate genes/ genomic site can be challenging, time consuming and expensive.

FP (provided a change in policy)

FP (provided a change in policy)

FP (provided a change in policy)

Gene editing is not legal in the UK and the Scottish Government is opposed to the use of GM in farming.

Appendix A: REA and stakeholder interviews methodology

REA methodology

The REA methodology used for this project aligned with NERC methodology (Collins et al., 2015) and comprised of the following steps.

  1. Define the search strategy protocol, identify key search words or terms, define inclusion/exclusion criteria. This step helped to focus the review on the most relevant sources. Inclusion and exclusion criteria were also defined. For example, studies related to reducing emissions through feed additives were excluded.
  2. Searching for evidence and recording findings. Due to the short timescales of this REA, we searched for literature using Google Scholar, utilising our accounts with Science Direct and Research Gate to access restricted pdfs where required. For each search, we recorded the date, search string and number of results found, each search string was assigned a reference number. Examples of search strings include:
    1. breeding for reduced methane emissions
    2. policy drivers for reduced methane emissions in livestock “breeding”
    3. breeding for reduced methane emissions in livestock “Scotland”
  3. Screening. Evidence was then screened, initially by title and a selection of sources were screened by the abstract, applying the criteria developed in step 1. This step ensures the relevance and robustness of the evidence that was included in the study.
  4. Extract and appraise the evidence. Evidence was then extracted from the papers after screening, this included methane reduction values, traits that lead to reduced emissions and the technologies involved in the process.

Stakeholder interview methodology

Stakeholder interviews were used to collect information that may have been absent from the literature, for example on trials currently taking place that will not yet be included in publications. The stakeholders included researchers and individuals from farmer representative groups. We invited farmers for interview, however, only confirmed one farmer for an interview.

The semi-structured interviews took place over Microsoft Teams, with questions covering all parts of the study. For instance, asking for views on the key traits to select for, any examples of farmers choosing livestock based on emissions and the benefits and risks.

We did seven one-to-one interviews (with four stakeholders based in Scotland) and a group interview with nine stakeholders, all located in Scotland. The group interview was done to allow space for conversation and discussion between stakeholders. During this meeting, we presented the key themes raised in the one-to-one interviews. This included the barriers and drivers to uptake, the availability of technologies and the structural needs to support uptake.

Appendix B: New Zealand sheep case study

Country information

New Zealand is an island nation in the South Pacific and has many similarities to Scotland in terms of its geography and climate. Agriculture is integral to the New Zealand economy with the sector accounting for 10% of gross domestic product (GDP), over 65% of export revenue and almost 12% of the workforce. In 2023 there were 26,821,846 sheep in New Zealand, down from approximately 70,000,000 in the 1980s.

Around half of GHG emissions in New Zealand (49% in 2021) and 91% of biogenic methane emissions stem from agriculture, with sheep farming a key contributor.

New Zealand has relevant international and domestic emissiontargets, including the Global Methane Pledge, and the Climate Change Response (Zero Carbon) Amendment Act 2019, which sets a net zero target by 2050. There is a specific reduction target for biogenic methane of 10% relative to 2017 levels by 2030, and 24 – 47% by 2050. New Zealand also has emissions’ budgets and emissions’ reduction plans which sets out policies and strategies for meeting the budgets.

Accelerating new mitigations such as breeding for low-methane sheep is seen as an important way to reduce emissions alongside the pricing of agriculture emissions, as well as support initiatives.

Relevant research, programmes and technologies

The New Zealand Agricultural Greenhouse Gas Research Centre (NZAGRC) and the Pastoral Greenhouse Gas Research Consortium (PGgRc) are key leaders in the robust and comprehensive programme of research in New Zealand.

  • The NZAGRC is a Government funded centre which invests and coordinates research for practical and cost-effective reductions of agricultural GHG. One of its main targets of reducing enteric methane emissions.
  • The PGgRc is a joint initiative of the New Zealand Government and the agricultural sector which funds research into ways to reduce methane emissions, including from sheep, such as breeding. It also provides knowledge and tools for farmers to help mitigate GHG, for instance research reports (‘Sheep farmers now able to breed “low methane” sheep’), and fact sheets, with the aim of increasing understanding around the research.

The NZAGRC and PGgRc led the following research programmes related to breeding for reduced methane emissions:

  • Low emitting sheep were genotyped and markers were used to identify low emitting traits which confirmed a genetic basis for the variation in methane emissions. After 13 years of selecting for low emitting traits, a 16% difference in methane emissions was found between low and high emitting sheep. Other key findings include no negative impacts on physiology, productivity and health when selecting for reduced emissions. Predications have also been made that with the low emitting flock a 1% decrease in methane emissions per year is achievable The low emitting flock has been producing more wool and leaner meat and the emissions savings are both permanent and cumulative. This programme is ongoing and has produced one of the most comprehensive datasets in the world.
  • A methane breeding value was launched in 2019 from research undertaken by NZAGRC and PGRC. This was made available to selected ram breeders through Beef + Lamb Genetics and gives the sector a practical tool to make decisions with. This has then led to the development of the Cool Sheep Programme.
  • The Cool Sheep™ Programme was launched in 2022. This three-year programme aims to provide every sheep farmer in New Zealand the chance to use genetic selection to reduce GHG emissions. As well as supporting farmers, this programme gathers phenotype data which feeds back into research. This is available to farmers who are reviewing rams for selection on N Prove. Breeders wanting to produce low-methane rams do so by measuring a proportion of their flock using PAC. When combined with other information and sheep genotyping, this is used to provide a methane breeding value. In November 2023, bookings for use of the PAC chambers by stud breeders were fully subscribed, indicating uptake is high. They note that progress is slow in terms of methane emissions reduction around 2-3% per year, with single trait selection, although this is cumulative.

The four workstreams of the project are:

  1. Ram supply: Measuring rams with PAC to make low-emitting rams available for breeding.
  2. nProve enhancement: adding methane to nProve.nz.
  3. National Impact: using GHG calculators on farms to show methane reductions, rewarding farmers for their efforts.
  4. Awareness and outreach: increasing knowledge for farmers, improving public awareness of efforts to reduce emissions while improving national productivity.

Key policies

There is no government policy legislating livestock breeding for reduced methane emissions in New Zealand. However, there are policies that that may contribute to introducing this in the future.

The Emissions Trading Scheme (ETS) is a key tool in New Zealand to help reduce emissions. Under the ETS, businesses must measure and report on their GHG emissions, and surrender one ‘emissions unit’ (an NZU) to the Government for each tonne of emissions emitted. They do this by purchasing NZU. The Government sets and reduces the number of NZU supplied into the scheme over time. This limits the quantity that emitters can emit, in line with emission reduction targets. Businesses who participate in the ETS can also buy and sell units from each other i.e. emitters can buy NZU from forestry companies or farmers to offset emissions. The price for units reflects supply and demand in the scheme. All sectors of New Zealand’s economy, apart from agriculture, pay for their emissions through their ETS surrender obligations. The agriculture sector must report its emissions but does not have surrender obligations.

Currently, no major incentive exists for agricultural producers to reduce their emissions. The ETS was not seen as the right mechanism to price agricultural emissions.

Instead, Government, industry representatives and Māori formed the He Waka Eke Noa – Primary Sector Climate Action Partnership (the Partnership) to reduce agricultural emissions. It is committed to designing an on-farm pricing system that ensures New Zealand’s agricultural products remain internationally competitive while reducing emissions.

Key Stakeholders

Key stakeholders involved in the research, technologies, programmes and policies include:

  • Agricultural Greenhouse Gas Research Centre, Government-funded centre which invests and coordinates research for reductions of agricultural GHG.
  • Crown Research Institutes, Crown-owned companies that carry out scientific research.
  • Beef + Lamb New Zealand, a farmer-owned, industry organisation representing New Zealand’s sheep and beef farmers.
  • Dairy Companies Association of New Zealand, representing dairy manufacturing and exporting companies.
  • Dairy NZ, industry organisation that represents all dairy farmers.
  • Farmers.
  • He Pou a Rangi – Climate Change Commission, an independent Crown entity that provides advice to government on climate issues
  • Iwi Māori, tribal entities and largest social units in Māori society that represent a group of people and land area
  • Māori Landowner groups, groups that represent Māori land that is governed and protected under specific statutes
  • Meat Industry Association, voluntary trade association representing red meat processors, marketers and exporters
  • Ministry for the Environment, New Zealand Government’s primary adviser on environmental matters
  • Pastoral Greenhouse Gas Research Consortium, provides knowledge and tools for farmers, to mitigate GHG
  • Public
  • Scientists and academics

Successes of research, technologies, programmes and policies

There are many successes in New Zealand for identifying emissions savings, policy drivers and behaviour change which would lead to improved breeding for reduced emissions.

  • Full subscription of the Cool Sheep programme to use genetic selection to reduce GHG emissions highlights the keen interest in this programme from farmers

Research indicated that sheep can be bred to produce less methane without sacrificing productivity.

Within the proposal for emission pricing, there have been the following successes that are likely to help drive behaviour change to uptake methane emission reduction breeding selection:

  • A farm level, split-gas levy gives farmers flexibility to determine the most efficient, cost-effective mitigation practices for their farms (Stakeholder comment, 2023).
  • The He Waka Eke Noa partnership involved key stakeholders discussing practical solutions to reducing emissions (Stakeholder comment, 2023).
  • While a policy for pricing agricultural emissions has not yet been legislated and implemented, discussions about a policy helped make New Zealand farmers more aware of their emissions and how to manage them.

Challenges of research, technologies, programmes and policies

There are some challenges with the New Zealand scenario that are relevant for identifying emissions savings, policy drivers and behaviour change which would lead to improved breeding for reduced emissions.

  • The fully prescribed uptake of the Cool Sheep programme in 2023 may highlight potential challenges with sourcing enough infrastructure to support all farmers interested in the programme.

In particular, there are challenges related to the agriculture emissions pricing:

Mitigation options under proposed policies are more currently more suited to dairy farmers than sheep and beef farmers.

The sheep and beef sectors are expected to be impacted by the pricing of emissions more than other farming sectors. There are likely to be disproportionate impacts on Māori due to the large proportion of Māori ownership in the sheep and beef sectors and historical context.

 

Potentially ancillary challenges and unforeseen challenges from the proposal such as environmental and social challenges due to land use changes due to the need to reduce emissions i.e. increased planting of forest may lead to landscapes changes etc.

The recent change in Government has posed a challenge. The 2025 implementation target for implementing the pricing of emissions is expected to be pushed back until 2030 (Stakeholder comment, 2023) and uptake of other methane related programmes could waver too.

Relevance in Scotland

There are some key learnings from the New Zealand scenario that are relevant for identifying emissions savings, policy drivers and behaviour change which would lead to improved breeding for reduced emissions.

  • At this stage, it is hard to determine exactly what has encouraged uptake of the Cool Sheep Programme and PAC measurements by sheep farmers. However it is assumed that discussions around agriculture emissions pricing and increased awareness, as well as financial assistance, has no doubt contributed to uptake.
  • The He Waka Eke Noa partnership highlighted that each livestock sector has different requirements. In Scotland, for example, stakeholders interviewed for this project suggested that it may be difficult to introduce breeding practices in the sheep sector due to its extensive nature. In addition, there is less frequent cashflow in the sheep and beef sectors compared to dairy, making it more difficult to introduce new practices. In New Zealand suggestions have been made that the dairy industry has had a better lobbying influence in the development of the policy than the sheep and beef industry and have been more successful at influencing a policy that better suits their needs (Stakeholder comment, 2023). Therefore, any consultations or partnerships must include different livestock types and stakeholders, and consider the differences between upland or lowland systems.

New Zealand is one of the first countries in the world to attempt to price agriculture emissions therefore can provide a huge amount of learning that should be considered by Scotland in developing policy around methane reduction.

Having an emissions number to reduce from makes it easier to see how actions will impact. This will encourage the consideration of emission reductions as part of general on-farm decision making, on-farm investment decisions and other considerations.

  • The policy impacts on certain farmers and Māori may be of relevance to island farmers and crofters with unique challenges, who may be disproportionately impacted by any climate policies in Scotland.
  • Research from the NZAGRC and the PGgRc has produced schemes like the Cool Sheep Programme.
  • The ram selection tool nProve provides a user-friendly platform for farmers to select the traits they want from a ram, including methane production. It gives farmers a tool to compare emissions between different animals before purchasing a ram, bull or semen. Because of the Cool Sheep programme and because there are planned policies to reduce emissions, there may be an incentive to use this metric. It may be possible to build on existing tools such as ScotEID and RamCompare in the future to create a similar platform (not only for sheep).

A policy for pricing agricultural emissions has not yet been legislated and therefore whether it has/will contribute to reduced emissions is yet to be realised. However government modelling suggests that the levy could achieve sufficient emissions reductions to meet or exceed methane targets. Discussions about a policy helped make New Zealand farmers more aware of their emissions and how to manage them.

Appendix C: Canada dairy case study

Country information

Canada has similarities in climate and geography to Scotland. Agriculture is a key aspect of the Canadian economy with agriculture and the agri-food system generating $143.8 billion Canadian Dollars (CD$) (around 7%) of Canada’s GDP. Canada is also the fifth-largest exporter of agri-food and seafood in the world. Dairy is a key part of the sector and is a top commodity in five of Canada’s provinces/territories.

In 2020, agriculture was responsible for 30% of Canada’s total methane emissions, with 86% of that being attributed to enteric fermentation. Canada has an emissions reduction target of 40% below 2005 levels by 2030 and to be net-zero by 2050 and joined the Global Methane Pledge. The advocacy group, Dairy Farmers of Canada, have voluntarily set a goal to reach net-zero by 2050.

Description of relevant research, programmes and technologies

Canada is undertaking research and programmes focused on breeding and new genomic technologies for reduced methane emissions in dairy production systems:

  • The Efficient Dairy Genome Project (EDGP) developed genomic-based methods for selecting dairy cattle with reduced methane emissions and improved feed efficiency. The project was underpinned by an extensive database used for genomic analysis. For example, correlating MIR with reduced methane emissions. The project also recognised the necessity of featuring the economic, environmental and social benefits of selecting for reduced methane emissions.
  • The Resilient Dairy Genome Project (RDGP) aims to integrate genomic approaches to improve dairy cattle resilience and industry sustainability. The project builds on the EDGP, with a focus on additional data collection, management and visualisation to support genomic analyses. Researchers noted an essential component is understanding the interaction between enteric methane emissions and specific farm conditions. For example, predicting methane emissions of individual animals and whole herds using milk MIR spectroscopy. By acknowledging the crucialness of collaboration with industry partners, the project will ensure results will render user-friendly products to enable technological uptake.
  • An ongoing commercial endeavour between genetic evaluation provider, Lactanet Canada and genetics supplier, Semex Alliance aims to develop a reliable methane efficiency index that can be easily integrated with common selection indices such as fertility, disease resistance and lifetime profitability.

Description of key policies related to reducing methane emissions through breeding

There are currently no government policies legislating livestock breeding for reduced methane emissions in Canada, however there are some policies that are likely to eventually incentivise it.

Key Stakeholders

Key stakeholders involved in the research, technologies, programmes and policies include:

Successes of research, technologies, programmes and policies

There are many successes in the Canadian scenario that are relevant to identifying potential emissions savings, and in identifying policy drivers and behaviour change which would lead to improved breeding for reduced emissions.

  • Researchers from the EDGP and RDGP recorded enteric methane emissions of reference populations predominantly via a GreenFeed system, a device measuring air composition exhaled by each cow during feeding. Exploiting the correlation between milk composition and emissions instigated the proposal of a genomic evaluation of methane efficiency without sacrificing other production traits. The projects demonstrated a 30% difference either side of average in enteric methane emissions between Holstein cows. This result highlights the importance of genetic selection if breeding for reduced methane emissions is to be an effective option.
  • Public-Private Partnerships (PPP) between research and industry can be accredited for the establishment of Canada’s major EDGP and RDGP, and were paramount in the development of the sophisticated database. Stakeholders Lactanet Canada and Semex Alliance effectively utilised this database, and in April 2023, Canada became the first country in the world to commercially market dairy semen containing methane efficiency as a relative breeding value (RBV). Their database and AI catalogue now includes 26 Holstein bulls with proven methane reduction capabilities, and a further 165 predicted. Semex Alliance also estimate widespread adoption of the low-methane trait could reduce methane emissions from Canada’s dairy herd by 1.5% annually, and up to 20-30% by 2050. The collective effort of all members of the Canadian dairy industry has enabled significant progression, to which the inclusion of a methane efficiency genetic valuation can be traced to.
  • A GHG Offset Credit System can incentivise farmers to undertake innovative projects that reduce GHGs for financial reward.

Challenges of research, technologies, programmes and policies

There are some challenges with the Canadian scenario that are relevant to identifying potential emissions savings, and in identifying policy drivers and behaviour change for improved breeding for reduced emissions.

Relevance in Scotland

There are some key learnings from the Canadian scenario that are relevant for Scotland in terms of identifying potential emissions savings, and in identifying policy drivers and behaviour change for improved breeding for reduced emissions.

  • When compared to other livestock sectors, the data gathering process in the dairy industry is unique as daily milking and feeding activities provide a non-invasive opportunity to measure individual animals without major management changes. Coupling the simplistic nature of data collection with advanced existing genetic databases and the widespread use of artificial insemination (AI), the Scottish dairy industry is capable of reducing enteric methane emissions efficiently. Applying knowledge or making predictions from existing information has great potential to eliminate and/or significantly reduce cost, data collection periods and the requirement of on-farm experimentation.
  • Genetic change is a simple and low-cost approach to reduce enteric methane emissions in dairy production systems. Owing to modern technologies and transport capabilities, the methane efficiency RBV developed in Canada is compatible with the Scottish dairy herd and can be purchased and administered via AI to help begin reducing enteric methane emissions.
  • Canada has precedented instigating good working relationships with farmers, a goal achieved by highlighting the primary objective of research is to enhance industry sustainability. In response, many Canadian dairy farmers have also recognised constructive engagement with research and industry is fundamental. The establishment of a comprehensive and transparent database has provided assurance and confidence to adopt new best management practices.
  • Scotland could consider monitoring the effectiveness of the Offset Credit System currently being considered in Ottawa to see if it incentivises behaviour change or changes finances and markets.
  • Canada does not currently offer incentives for low-methane cattle breeding, and livestock breeders do not charge a premium for methane efficiency traits. However, discussions on this topic are ongoing between stakeholders and policy makers and it is looking likely a financial benefit will be introduced in the future.

Appendix D: Ireland beef case study

Country information

Ireland has a similar climate and geography to Scotland. Agriculture is key aspect of the Irish economy with the agriculture, forestry and fishing GDP valued at €3,672m in 2020. In 2020, 55% of farms were specialist beef, with many others including cattle as part of a mixed farm.

In 2022, agriculture was responsible for 38.4% of GHG emissions, making it the sector with the biggest share of emissions. 62.6% was caused by enteric fermentation.

Ireland is part of the Global Methane pledge and legally obliged as an EU Member State to reduce emissions under the EU’s Effort Sharing Regulation, including in agriculture. Ireland’s 2030 target is to deliver at least a 42% reduction by 2030 compared to 2005 levels.

Ireland has developed the Food Vision 2030 Strategy for the Irish agri-food sector which commits to reducing biogenic methane. This includes the ‘Ag Climatise’ Roadmap, covering animal breeding, with an aim to genotype the entire national herd by 2030 to develop and enhance dairy and beef breeding programmes.

Description of relevant research, programmes and technologies

The Irish Cattle Breeding Federation (ICBF) launched the National Genotyping Programme (NGP) for cattle in 2023. This offers beef and dairy farmers a low-cost option to collect DNA samples from calves at birth which can be used for genotyping to identify specific traits or characteristics. The aim of the programme is to achieve a fully genotyped herd in Ireland. This has made national genetic indexes available to farmers, including methane traits. It also allows farmers to optimise the health and productivity of their herd, reducing its emissions intensity. The ICBF also publish methane evaluations for AI sires that have had methane data recorded.

Teagasc has an important role in the research in Ireland. Animal breeding is one of the four solutions from Teagasc to reduce methane emissions from livestock. Current research projects include:

  • GREENBREED: Measured methane at the Tully Progeny Test centre using a GreenFeed automated head chamber system. This research led to the publication of genomic evaluations for methane emissions in Irish beef cattle and sheep. It found notable differences in methane emissions from livestock being fed the same diet, 11% of these in cattle were found to be due to genetic differences. This indicates that breeding programmes to reduce methane will be effective in Ireland.
  • Collaborative research by Teagasc and ICBF found a 30% difference in methane emissions from beef cattle of a similar size. This lead to the residual methane emissions (RME)[10] index being identified as a metric to rank animals.

Description of key policies

There is no legislation on livestock breeding for reduced methane emissions in Ireland, but the following policies related to GHGs may support this.

  • The Beef Data and Genomics Programme (BDGP) paid suckler farmers to improve the genetic merit of their herd through data collection and genotyping, with the aim of lowering GHG emissions by improving quality and efficiency.
    • Payments were made of €142.50/ha for the first 6.66 ha and €120/ha for the remaining eligible hectares (the equivalent of €95 for the first 10 cows and €80 for the remaining cows), farmers have to undertake specific requirements.
    • These requirements include calf registration, detailed surveys of animal characteristics, genotyping and tissue tag sampling, and implementing a replacement strategy based on high genetic merit animals.
    • Additional support in the form of the carbon navigator decision making tool and training courses for farmers are also provided.
    • Participants of the programme were found to be achieving improvements at a faster rate compared to farms not taking part. The impact of the programme can help to promote smaller, more efficient suckler cows to produce more efficient beef.
  • The Suckler Carbon Efficiency Programme:

As part of its Common Agriculture Policy Strategic Plan (CSP), Ireland developed ENVCLIM (70) 53SCEP as a follow-on from the BDGP, providing support to beef farmers who implement breeding actions that aim to lower the overall GHG emissions. The BDGP was shown to deliver on both environmental and productive efficiency and emissions per suckler cow are being reduced through breeding strategies. Another measure in the CSP, 53SCT, targets training to complement the Suckler Carbon Efficiency Programme.

Key Stakeholders

Key stakeholders involved in the research, technologies, programmes and policies include:

  • Teagasc, Agriculture and Food Development Authority providing research, advisory and training to the agriculture and food industry and rural communities.
  • Department of Agriculture, Food and the Marine, Irish government department leading, developing and regulating the agri-food sector, protecting public health and optimising social, economic and environmental benefits.
  • Irish Cattle Breeding Federation (ICBF), non-profit organisation charged with providing cattle breeding information services.
  • Irish Environmental Protection Agency, independent public body to protect, improve and restore the environment through regulation, scientific knowledge and working with others.
  • Irish Farmers Association, Ireland’s largest farming representative organisation.
  • Farmers.
  • Food Vision Sheep and Beef Group, group of stakeholders established by the Minister for Agriculture Food and the Marine to identify measures that the sector can take to contribute to reducing emissions from the agricultural sector

Successes of research, technologies, programmes and policies

There are many successes in the Irish scenario that are relevant to identifying potential emissions savings, and in identifying policy drivers and behaviour change which would lead to improved breeding for reduced emissions.

  • The NGP is a useable database of genotyped methane information available for farmers to use. This is the result of comprehensive research programmes, collaboration between breed societies, and creating useful systems for farmers to benefit from. Making this data easily available to all farmers across Ireland can encourage behaviour change and is a successful programme that could be considered in Scotland. The creation of the ICBF has been essential for this, as it means there is one body overseeing all genotyping and data storage.
  • The BDGP is an example of how payments to farmers can be used to gather data and reward farmers for adopting positive practices.
  • Research from GREENBREED indicates that breeding programs to reduce methane emissions will be effective for selecting low-emitting livestock, especially combined with the national genomic evaluations, and will have no negative impact on performance and profitability.
  • Ireland has produced methane evaluations to enable farmers to identify opportunities to reduce emissions and improve the sustainability of their enterprise.
  • Overall, the authors did not find evidence of a quantifiable impact from introducing methane related actions and policies. This may be because the relevant research, programmes and technologies as mentioned above are still relatively new and it is too early to quantify. For example, the NGP is to only be completed by 2027, whereas following on from data collected from methane evaluations, methods are still being developed on how best to incorporate methane traits into beef and dairy production.

Challenges of research, technologies, programmes and policies

Additional research would be required to understand how the policies and programmes were received by farmers and how successful the agricultural community views them to be. We contacted Ireland representatives for involvement in stakeholder interviews however we did not get a response.

Relevance to Scotland

There are some key learnings from Ireland that are relevant for Scotland in terms of identifying potential emissions savings, and in identifying policy drivers and behaviour change for improved breeding for reduced emissions.

  • A national database was suggested by Scottish stakeholders (Stakeholder comment, 2023). Therefore, Ireland’s NGP provides an example for Scotland if this was to develop. In particular:
  • The use of metrics like Residual methane emissions (RME) index and

predicted transmitting ability (PTA) could give Scottish farmers and crofters an easy way of comparing their livestock to other farmers and understanding where they are compared to the average.

  • Challenges in the Scottish context could include reluctance on the part of different breed societies to pool data.
  • Ireland have shown that emissions for cattle can be reduced through appropriate breeding strategies and incentives for farmers. Such as subsidising DNA sampling of calves which helps to genotype the national herd.
  • The creation of the Food Vision Beef and Sheep Group to chart a path for the sector to meet the emissions emission targets is a potential model for ways that Scotland might bring key stakeholders into the development of key policies to reduce emissions.
  • The main ways behaviour change has been encouraged is by making the programmes and policies mentioned above easy to access, for example, the ICBF also provides information to help farmers make decisions about their herd through HerdPlus.
  • The BDGP and CSP provides training to farmers who are using the scheme, for which funding is provided.

Appendix E: Methodology and results for the quantification of potential emission savings

Methane emission savings are achievable through breeding and new genomic technologies. The main sources of methane from cattle and sheep in Scotland are enteric fermentation and managed manures. We have chosen to focus our calculations on emissions from enteric fermentation for two reasons:

  1. Methane emissions from managed manures are much smaller.
  2. Changes to livestock by selecting traits which lead to lower methane emissions will have a greater impact on the emissions from enteric fermentation rather than the emissions produced from livestock manures.

To align with the CCP’s targets, of achieving net zero in Scotland by 2045 and a 75% reduction in emissions by 2030, we present data for potential emission reductions for 2030 and 2045. The following data were used to quantify the potential emission savings:

  • Key traits leading to reduced methane emissions, from the REA.
  • Methane reduction values associated with traits, from the REA.
  • Note: A particular challenge was identifying emission reduction values that were associated with specific traits, that we could use in our calculations. We have used the data available to draw conclusions.
  • Baseline emissions data for Scotland from the National Atmospheric Emissions Inventory (NAEI, 2023).
  • Uptake values (sector specific) for adoption of chosen traits through breeding, based on findings in the REA, stakeholder interviews and expert judgement.

Baseline methane emissions

To calculate the baseline methane emissions for dairy, beef and sheep, the enteric fermentation emissions of the livestock types for Scotland in 2021 were extracted from the NAEI (2023)[11]

Current uptake rate for adoption of traits

The current uptake rate is an estimated current baseline based on evidence gathered in the REA review of evidence and technical knowledge. This provides a baseline for additional uptake under the scenarios presented below.

Current uptake is set at 75% for dairy cattle, due to the high usage of reproductive technologies (see Section 4.1.3), in particular use of sexed semen and artificial insemination (AI) using Holstein Friesian semen, a key breed which already has proven methane efficiency ratings published as part of the breeding profile. It is understood that methane efficiency ratings are also being developed for other key dairy breeds as observed on UK dairy and beef cattle semen sales websites.

Beef cattle uptake has been set at a 40% baseline as findings show that methane efficiency ratings are less regularly published as part of the beef breed profile on UK semen sales websites. However, artificial insemination of beef cattle is relatively common, although it is not a standard practice as in the dairy industry. It is understood adoption of breeding for reduced emissions is developing and evidence is being gathered (see Section 4).

The current baseline for sheep has been set at 10% based on a comparison with New Zealand where there is an uptake rate of 30% (Rowe et al. in 2020). Following discussions with Scottish Government it is acknowledged that there is some technology usage around the world, but that adoption in Scotland is not yet as high as in New Zealand. Therefore, 10% has been chosen as the baseline. This links to understanding of technology uptake in Section 4.

Scenarios

The quantification of emissions savings was based on four different scenarios to reflect various levels of uptake:

  • The no intervention scenario reflects an increase in uptake of 5% from the current baseline by 2030 and remains at the same level until 2045 for all livestock types.
  • The voluntary uptake scenario is designed to reflect levels of uptake expected with no other push such as a financial incentive or a relevant policy.  This scenario reflects a 5% increase in uptake from the current baseline by 2030, and an additional 5% increase in uptake by 2045 for all livestock types.
  • The supplier demand scenario is based on companies along the supply chain offering financial incentives to farmers that implement breeding techniques to reduce methane emissions.  This value is set at a mid-point between the voluntary uptake and the regulatory scenario.
  • The policy changes scenario represents the uptake where legislation has been introduced that will require farmers to introduce methane reducing breeding techniques to their herds. This scenario reflects a 10% increase in uptake from the current baseline by 2030. By 2045 it is assumed there would be 100% uptake for dairy cattle due to the large-scale usage of AI within the industry and progress seen on methane efficiency profiling already published within the key breed profile. It is assumed that beef cattle could reach 80% uptake by 2045, and sheep could reach a 60% uptake by 2045 under a regulatory scenario.

Scenario uptake values are presented for dairy, beef and sheep in Table 17.

Table 17. Scenario implementation values for dairy, beef and sheep

Type

Scenario

Current baseline

Change from current baseline to 2030

2030 uptake

Change from current baseline to 2045

2045 uptake

Dairy

1. No intervention

75%

5%

80%

5%

80%

2. Voluntary uptake

75%

5%

80%

10%

85%

3. Supplier demand

75%

7.5%

82.5%

17.5%

92.5%

4. Policy changes

75%

10%

85%

25%

100%

Beef

1. No intervention

40%

5%

45%

5%

45%

2. Voluntary uptake

40%

5%

45%

10%

50%

3. Supplier demand

40%

7.5%

47.5%

25%

65%

4. Policy changes

40%

10%

50%

40%

80%

Sheep

1. No intervention

10%

5%

15%

5%

15%

2. Voluntary uptake

10%

5%

15%

10%

20%

3. Supplier demand

10%

7.5%

17.5%

30%

40%

4. Policy changes

10%

10%

20%

50%

60%

Traits

Traits and technologies with a possible relationship with methane emissions and emission reductions were identified through a REA of relevant literature (see Section 4).

Traits identified were further reviewed to assess their applicability to emission reduction calculations. When assessing each trait to quantify the emissions savings, appropriate values were found to be scarce in the literature. There were two key reasons that led to studies and/or traits being excluded from use in this task:

  1. A significant portion of the literature did not present methane emission values and was instead looking at genetic correlations between traits. Therefore, literature that did not present methane emission values or change in methane emissions, either as absolute or relative values, were excluded.
  2. Often the changes in methane emission were comparative to a baseline that was not appropriate for our calculations focusing on methane emission from enteric fermentation. For example, papers excluded in our review presented changes to emissions from the entire lifecycle or system.

A summary of the traits, where appropriate values were obtained, are presented in Table 17 below.

Table 18. Traits identified with appropriate methane reduction values used in the calculations of emissions savings

Sector

Trait Category

Trait Name

Unit of baseline

Value of methane reduction from baseline

Beef

Production

Feed efficiency

kg CO2e/kg product

7%

Offspring carcass weight

kgCO2e/per kg meat per breeding cow per year

1.3%

Climate

Methane yield

gCH4/kgDMI per generation

12%

Dairy

Production

Feed efficiency

kg CO2e/kg product

5%

Milk fat + protein

MJ CH4/kg milk

12%

Milk yield

kg CH4/kg milk

15%

Climate

Methane intensity

kg CH4/kg milk

24%

Sheep

Production

Feed efficiency

kg CO2e/kg product

7%

Climate

Methane yield

g CH4/kg DMI

35%

Feed efficiency

References: (Alford, A.R. et al. 2006; Worden, D. et al. 2020; Rowe, S.J. et al. 2021)

The ability of animals to optimally convert feed into liveweight with minimal losses of energy, meaning that animals with high feed efficiency consume less than their peers with equivalent liveweight and weight gain. This trait was identified across all three livestock types and has been highlighted by the stakeholders and the literature as a key trait for emission reductions (see Section 4).

Methane focused climate traits

References: (Quinton, C.D. et al. 2018; De Haas, Y. et al. 2021; Jonker, A. et al. 2018)

Methane traits are likely to have the greatest impact on methane emissions. Here the methane related traits were focused on manipulating the gut microbiome and selecting for animals with certain microbial populations that led to lower methane emissions. While methane traits were identified for all three livestock types, they were presented differently across the literature.

Offspring carcass weight – Specific to beef cattle

References: (Martínez-Álvaro, M. et al., 2022)

Focus on offspring carcass weight in beef cattle reduces methane emissions through increased quantity of product per animal, therefore reducing the number of animals required to produce the same amount of beef product.

Milk yield and Milk fat and protein – Specific to dairy cattle

References: (Bell, M.J. et al. 2010)

Traits reduce methane emissions per kg of milk while maintaining production levels and quality.

Emissions reduction

To calculate the emission reduction of different traits under the different scenarios the following formula is used:

Where:

= Emissions savings (kt CH4 for the livestock type)

= Baseline emissions (kt CH4 for the livestock type)

= Uptake (U) for the projected year (y)

= Emission reduction coefficient (%)

This formula calculates a percentage of emissions based on emissions reduction potential and uptake rate and subtracts this portion from baseline emissions. The result is an estimate of methane emissions if the reduction potential and uptake for the trait is achieved. The savings were then calculated by subtracting the estimated emissions from the baseline emissions, and both were calculated in units of percentage of baseline and absolute values (kt CO2e). This calculation was completed for each trait found in beef, dairy, and sheep sectors, for the years 2030 and 2045.

Limitations in the data:

  • All traits have been presented separately as the interaction between traits and the impact this would have on emission reductions is unknown.
  • It is acknowledged that traits found within the literature are presented in different units (see Table 7). Traits selected from the literature also presented a percentage change which was used within the change calculations. The percentage change has been applied to total emissions from the relevant livestock sector due to limited data on specific emissions related to more specific production categories such as CH4 emissions per kg milk produced.
  • Methane efficiency focused traits have shown to have the greatest methane reduction potential for all three livestock types. However, it is noted that there was less literature available on this subject compared to feed efficiency. Due to the smaller quantity of literature available the reduction potential values selected for methane efficiency could be less robust. Greater consistency in measurement, modelling, and presentation of methane efficiency traits and their impacts on emissions savings and animal performance production could be useful research to fill this knowledge gap.
  • Traits reduction factors compiled within the review were presented in different units, however, all presented a percentage reduction. It has been assumed that the percentage reduction would be applicable to be used as a reduction factor as this would have a direct impact on methane reductions independent of the unit the factor was recorded in.
  • Limited data was provided within the literature reviewed on the length of time until each trait reaches maximum potential within the population. However, it is assumed that once the trait has been bred into the total population there will be no additional improvements unless new breeding traits are selected. Within the calculations we have assumed that traits will account for their maximum potential to the selected population at the assessment point (i.e., in 2030 100% of the trait will apply to the current baseline uptake with the additional percentage uptake).
  • There is the possibility that, due to the nature of genetics, when selecting for certain traits, that they will not fully spread throughout the entire population where the trait is applied. This is a complicated process, and it has been assumed that at each assessment point (2030 and 2045) each trait has reached maximum spread in the portion of the population that has taken up the measure (i.e., in 2030 100% of the trait will apply to the current baseline uptake with the additional percentage uptake).

Results

Figures 4-7 show that in each sector, up to 2030, the reductions are relatively steady, but there is a greater reduction at 2045, influenced by the proposed increase in uptake. Due to the proposed uptake percentages the policy change scenario presents the greatest reduction under all traits, with the no intervention scenario showing the smallest reduction due to a 5% increase in uptake in 2030 and no further uptake in 2045.

Figure 4 presents the methane emissions under the four scenarios for the three traits selected for beef cattle: feed efficiency, offspring carcass weight and methane production. The methane production focused trait has the largest emission reduction (reduction of 161.1 kt CO2e in 2045 under the policy changes scenario), whereas the offspring carcass weight focused trait has the smallest impact at less than 12.4 kt CO2e reduced by 2045 under the maximum reduction scenario.

In correlation with beef trait reductions, methane intensity traits have the largest reduction to methane emissions in dairy cattle, with a reduction of 35.4 kt CO2e observed under the policy change scenario by 2045, as presented in Figure 5. While breeding for methane reductions through feed efficiency has the least change at 7.4 kt CO2e reduced by 2045, this could be due to the work already completed on feed efficiency breeding within dairy. Traits focused on milk fat and protein and milk yield provide similar reduction level levels, however there is the potential for overlapping improvements with feed efficiency as breeding focused on improvements to milk production traits could also link to improvements to feed efficiency.

Reduction potential for sheep is presented in Figure 6 for the two selected traits: feed efficiency and methane yield. As with the cattle categories, the trait focused on methane improvements (methane yield) had the largest potential reduction at 185.6 kt CO2e reduced by 2045 under the policy change scenario, whilst feed efficiency traits saw a smaller reduction of 37.1 kt CO2e by 2045 under the policy change scenario.

Figure 4. Methane emissions for beef cattle traits against the 2021 baseline enteric methane emissions of beef cattle in Scotland. Please note the y-axes do not start at zero to allow for greater visibility of results.

 

Figure 5. Methane emissions for dairy traits against the 2021 baseline enteric emissions of dairy cattle in Scotland. Please note the y-axes do not start at zero to allow for greater visibility of results.

Figure 6. Methane emissions for sheep traits against the 2021 baseline enteric emissions of sheep in Scotland. Please note the y-axes do not start at zero to allow for greater visibility of results.

Figure 7 presents the methane emissions by 2045 under all scenarios for all traits for each livestock type. The difference in total enteric fermentation emissions for each livestock type can be seen by the dotted baseline line. Beef cattle emitted the majority of the methane from enteric fermentation in Scotland in 2021, with sheep emissions being less than half those of beef cattle, and dairy under a quarter those of beef cattle.

 

Figure 7. Methane emissions for all livestock for all traits presented against baseline enteric emissions of beef, dairy and sheep in Scotland.

How to cite this publication:

Jenkins, B., Herold, L., de Mendonça, M., Loughnan, H., Willcocks, J., David, T., Ginns, B., Rock, L., Wilshire, J., Avis, K (2024) ‘Breeding for reduced methane emissions in livestock’, ClimateXChange. http://dx.doi.org/10.7488/era/5569

© The University of Edinburgh, 2024
Prepared by Ricardo PLC on behalf of ClimateXChange, The University of Edinburgh. All rights reserved.

While every effort is made to ensure the information in this report is accurate, no legal responsibility is accepted for any errors, omissions or misleading statements. The views expressed represent those of the author(s), and do not necessarily represent those of the host institutions or funders.

ClimateXChange

Edinburgh Climate Change Institute

High School Yards

Edinburgh EH1 1LZ

+44 (0) 131 651 4783

info@climatexchange.org.uk

www.climatexchange.org.uk


  1. See methodology in Appendix A, section 9.1



  2. DNA contains the information required to create the entire organism, a unit of DNA containing specific information to create a protein or set of proteins is referred to as a gene. It is these proteins which make up the body and control chemical reactions between cells. the study of genes is referred to as genetics.



  3. The productive lifespan of livestock. For beef and dairy – a longer productive lifetime would reduce the number of replacement heifers needed to maintain a constant herd size. For sheep – the longer ewes can produce lambs, production efficiency improves.



  4. The number of lambs born per number of ewes mated, expressed as a percentage.



  5. For beef and dairy – less feed is used for the same output of product and less loss of energy to methane (kg CO2e/kg product). For sheep – this is CO2e but as far as can be told it is only methane in this value. Less feed is used for the same output of product and less loss of energy to methane (kg CO2e/kg product).



  6. The number of kilograms gained by the animal per day, measured in kg/day.



  7. Overall production of the animal (including feed efficiency), supporting the animal to reach its full genetic potential and ensuring it reaches the highest possible level of performance.



  8. ME is expressed as a Relative Breeding Value (RBV) with a mean score of 100 and a standard deviation (how much a point differs from the average), of five. A score below 100 indicates below average and a score above 100 indicates above average. A higher RBV indicates a higher methane reduction potential.



  9. The amount of methane produced per unit of milk or sheepmeat produced (kg CH4/kg milk/sheepmeat).



  10. RME is the difference between the expected methane emissions from an animal based on its size and feed intake, compared to what it actually produces. High RME is undesirable and low RME is desirable.



  11. © Crown 2024 copyright Defra & BEIS via naei.beis.gov.uk, licenced under the Open Government Licence (OGL).


The generation of energy from organic matter, such as plants, is called bioenergy. The Update to the Climate Change Plan (CCPu) identifies the significant role that bioenergy could play in delivering Scotland’s legally binding commitment to achieve net zero by 2045.

This research examines the economic potential of perennial energy crops (PECs) for farmers and land-managers in Scotland, as well as the wider economic implications.

The three PECs considered are miscanthus, short rotation coppice (SRC) and short rotation forestry (SRF).

Findings

  • PECs have the potential to generate income for farmers and land-managers in Scotland.  
  • Miscanthus showed the highest average gross margin of the three crops studied but in Scotland there is more suitable land for growing SRC and SRF.
  • Farmers and land managers may view PECs as a risky proposition due to uncertainty about market demand and achievable crop sale prices, combined with the need for upfront investment to establish production.
  • The most economically and environmentally advantageous approach is likely to be site-specific and determined by local circumstances. 

For further information on the findings please download the report.

If you require the report in an alternative format, such as a Word document, please contact info@climatexchange.org.uk or 0131 651 4783.

Research completed in December 2023

DOI: http://dx.doi.org/10.7488/era/5478

Executive summary

Background

The generation of energy from organic matter, such as plants, is called bioenergy. The Update to the Climate Change Plan (CCPu) identifies the significant role that bioenergy could play in delivering Scotland’s legally binding commitment to achieve net zero by 2045. This could be achieved whilst also supporting a green economic recovery from the effects of the Covid-19 pandemic and a just transition that creates jobs and supports people and rural communities.

To meet this expanded role for bioenergy in Scotland, a scaling up of domestic biomass production would be required. The UK Climate Change Committee (CCC) highlighted the opportunity for domestic production as a key pillar for delivering the CCPu ambition.

This research examines the economic potential of perennial energy crops (PECs) for farmers and land-managers, as well as the wider economic implications. The three PECs considered are miscanthus, short rotation coppice (SRC) and short rotation forestry (SRF).

Key findings

Profitability of perennial energy crops

  • PECs have the potential to generate income for farmers and land-managers in Scotland.
  • Comparison of gross margins shows income from PECs is likely to be lower than from other typical farm enterprises on suitable land, such as lowland cattle and sheep and ‘mixed agriculture’. This is assessed on the basis of yearly average gross margins over the lifetime of the PEC in comparison to equivalent gross margins for other farm enterprises.
  • Income (gross margin calculation) from PECs compared very favourably in the analysis compared to the farming type known as ‘general cropping: forage’. This is growing crops for animal consumption, usually on lower quality land, and it typically makes a significant loss.
  • There is a need for greater confidence that PECs will deliver good economic returns in order for them to be viewed as an attractive, economically viable option by farmers and land managers in Scotland. High upfront establishment costs for perennial energy crops and low revenue potential are both likely to hinder uptake.
  • Miscanthus showed the highest average gross margin of the three crops studied, at £382 per hectare per year. However, there are some potentially limiting factors:
    • There is uncertainty about achievable yields in the Scottish climate and on the grades of land above category 4.1 in the Land Capability for Agriculture in Scotland.
    • There is limited theoretical growing area in Scotland, which is much lower than for SRF or SRC.
  • SRF and SRC showed lower profitability for farmers: £80 and £87 per hectare per year over their lifetime respectively for ‘SRF: broadleaved’ and SRC. However, there is more suitable land for growing these.
  • SRF conifer would see a negative gross margin, given that the production costs outweigh the value of the crop sold.

Potential opportunities

  • PECs could help diversify a business, creating additional income, without adding significant additional labour requirements or ongoing input costs because minimal management time and inputs are required once crops are established.

Potential barriers

  • Cash flow could pose a barrier to uptake. The distribution of costs and income year-on-year for PECs is significantly different to typical farming activities which have an annual profit cycle. PECs need investment in site preparation and planting upfront, but income only arrives after first harvest several years later. This is 2-3 years for miscanthus with subsequent annual harvests, 6 years for SRC with periodical harvests thereafter, and 15 years for SRF first and only harvest.
  • Farmers and land managers may view PECs as a risky proposition due to uncertainty about market demand and achievable crop sale prices, combined with the need for upfront investment to establish production.
  • Other potential barriers to uptake include: farmer and land-manager unfamiliarity with PEC production, low appetite for risk, need for new skills, access to equipment and services, concerns about community perception of land-use change, and impacts on other agricultural production, e.g. available animal feed.

Enhancing economic potential and production

Potential approaches to improve the economic potential of PECs in Scotland include:

  • Financial incentives, such as government specific subsidies under future agricultural support or other market-focused incentives.
  • Risk reduction strategies, such as secure, attractively priced contracts with end markets, alongside expansion of the market.
  • Innovations to allow processing at the farm and to improve transportability of crops could also help to increase the economically viable travel distance.
  • Improving access to skills and knowledge to produce PECs could also remove a barrier to uptake, if economic prospects are improved.

Implications for wider Scottish economy

  • Future demand for PECs to support the Scottish Government’s climate ambition is likely to require increased production, and previous research suggests 38,000 hectares could be feasibly planted by 2032 and 90,000 by 2045.
  • We modelled two demand scenarios to illustrate the potential range in results if land was transitioned to growing PECs:
  • Scenario 1: conversion of approximately 38,000 hectares. This would result in an economic gain in terms of increased gross margin of around £9.6 million. This would however result in a shortfall in non-PEC agricultural yield (crops, stock-feeding crops and grass) of between 537,600 and 700,000 tonnes.
  • Scenario 2: conversion of approximately 90,000 hectares. This would result in an economic loss of around £9.5 million per year, based on gross margin, and a shortfall in non-PEC agricultural yield (crops, stock-feeding crops and grass) of between 708,200 and 1.6 million tonnes. The financial loss is because under this scenario more economically advantageous land is transitioned to PECs and the PECs perform less well economically.

Economically viable production locations

  • Economically viable production locations for PECs are influenced by multiple factors including proximity to markets and local access to services and facilities for crop management, such as harvesting contractors, to avoid incurring excessive costs.
  • The research identified suitable growing regions (some SRC/miscanthus and most for SRF) within an economically viable transport distance to existing biomass plants and potential sites for Bioenergy with Carbon Capture and Storage (BECCS) near the proposed east coast carbon capture and storage feeder pipeline (assumed 50-100 km).
  • Economic viability may be a barrier to SRF production increases even if suitable land is available, given that it is economically uncompetitive against other land use options.

Potential further steps

Key debates and areas for further research include:

  • Considering more in-depth ‘whole farm’ economic analysis. This study focused on gross margin comparison, which is useful for comparing specific crops and farm enterprises, but has limitations in terms of how well it allows assessment of integration of energy crops into a whole farm business. This will vary farm to farm but could be explored through farm case studies. This could include considering a wider range of costs for farmers and that after initial set up the PECs would require less workload.
  • Comparing the economic and environmental potential of using land for energy crops with utilising the same land for other renewable energy options, such as using the land for solar panels alongside grazing.
  • Exploring the potential role for on-farm use of perennial energy crops.
  • Considering future biomass markets, including how future Greenhouse Gas Removal (GGR) schemes, global demand and demand from biotechnology sector may impact it.
  • Identifying how to make domestic biomass from energy crops a more attractive option than imports and a more profitable use of land, and on what basis this can be justified. For example, taking account of full LCA and rewarding greatest emission saving.
  • Considering in more detail the role of PECs in the context of how the agriculture sector is changing and how it may have to change to reduce GHG emissions.
  • Considering the value, including the financial value, of other benefits of energy crops, such as flood mitigation or animal shelter, relative to existing or potential alternative land-uses.
  • Exploring how PECs support/interact with tier 2 or 3 objectives of the ARP.
  • Considering the impact of subsidies.

The most economically and environmentally advantageous approach is likely to be site-specific and determined by local circumstances. Making judgements about the best use of land is complex for policy makers, farmers and land managers alike. Guidance on this decision-making is likely to be needed.

Abbreviations table

BECCS

Bioenergy with Carbon Capture and Storage

CCC

UK Government Climate Change Committee

CCPu

Scotland’s Climate Change Plan Update (2020)

CXC

ClimateXChange

LFA

Less Favoured Area (a designation in Scotland for disadvantaged agricultural areas – including crofting)

NETs

Negative Emissions Technologies

PEC

Perennial energy crops

SRC

Short Rotation Coppice

SRF

Short Rotation Forestry

 

Introduction

This evidence assessment focuses on examining the economic potential of perennial energy crops (PECs) for farmers and land-managers in Scotland, along with considering the wider economic implications for Scotland. The assessment builds upon recent ClimateXChange reports which demonstrated that there are significant opportunities for the expansion of perennial energy crop cultivation in Scotland (Martin et al, 2020) and that increased supply of biomass for energy generation from such crops will be needed to meet forecast future demand in the context of Scotland’s climate mitigation plan goals (Meek et al, 2022). However, in scaling up domestic biomass production it is important to consider how the economics intersect with other relevant issues including biodiversity, land-use, water management and a ‘just transition’. This report aims to consider these issues, alongside the economics and support the Scottish Government’s development of policy in relation to perennial energy crop production.

The policy context for energy crops in Scotland

The Scottish Government’s Update to the Climate Change Plan (CCPu) forecast a role for Negative Emissions Technologies (NETs) , including bioenergy with carbon capture and storage (BECCS), to remove carbon dioxide from the atmosphere to compensate for residual emissions. ). The UK Climate Change Committee (CCC) acknowledges Scotland’s opportunity to scale up domestic biomass production to meet this aim, recommending careful consideration of impacts on land-use and agriculture. In line with Scottish Government’s Vision for Agriculture, and set out in the Scottish Agricultural Bill, future subsidy support which will replace Common Agricultural Policy, will be split across unconditional support and support targeted to sustainable food production and environmental outcomes, including low carbon farming and biodiversity. Scotland’s draft ‘Energy Strategy and Just Transition Plan’ aims to use bioenergy where it can best support Scotland’s Net Zero Journey, and aligns with and supports Scotland’s goals for protecting and restoring nature. Considering the role for production of PECs in the evolving Scottish policy landscape will be critical.

Alongside this the UK Government has also published a new biomass strategy, which aims to support sector growth and strengthen biomass sustainability. The strategy acknowledges that bioenergy policy involves a mix of reserved and non-reserved powers, and so as the Scottish Government develops its Bioenergy Policy Statement, Scotland has an opportunity to build on UK policies and develop policies appropriate for Scotland. Further policy information is included in Appendix A.

Introduction to perennial energy crops for Scotland:

Previous research for CXC identified that perennial energy crops (PEC) present opportunities for scaling up biomass production in Scotland, with short-rotation coppice (SRC), short-rotation forestry (SRF) and energy grass Miscanthus, showing most potential (Martin et al, 2020). Details of each crop can be found in Appendix B. PECs support climate mitigation by providing a renewable energy source; displacing fossil fuel use; helping to reverse soil carbon loss, and acting as a carbon sink. When used for energy generation and combined with carbon capture and storage (CCS), such crops have the potential to generate negative emissions and contribute towards Scotland’s net zero ambitions. PECs can also bring additional benefits, such as flood mitigation (see Section 4 below for further details).

Figure 3.2: Schematic diagram of bioenergy with carbon capture and storage [1]

Schematic diagram of bioenergy with carbon capture and storage showing how biomass absorbs carbon dioxide, which is then burned for electricity or converted into biofuels. The carbon dioxide emissions resulting from use of the biomass or biofuel combustion are then stored.

Currently, Scotland grows only a small area of PECs – about 250 ha (Martin et al, 2020). Previous geo-spatial mapping work for Scotland (Martin et al, 2020) has shown theoretical potential for approximately 900 kha of land, to be suitable for PECs (913kha SRF, 219 kha SRC and 52kha Miscanthus – with some overlap between suitable areas) mainly in the east and the lowlands. This analysis considered topography, soil type, climatic variables and suitable land capability classes[2] to identify these theoretically feasible growing areas. Future demand for PECs to support the Scottish Government’s climate ambition is likely to require increased production of such crops.

Markets for PEC Biomass in Scotland

Research[3] has identified the following potential uses of biomass via ‘Negative Emissions Technologies’:

  • BECCS Power – bioenergy with carbon capture and storage (BECCS) for electricity in a power station
  • BECCS hydrogen – either via gasification of biomass or steam methane reforming of biomethane, with carbon capture and storage
  • BECCS in industry (for heat and other industrial processes)
  • BECCS Biomethane – processing of biomass via Anaerobic Digestion (AD), gasification or pyrolysis, with carbon capture and storage
  • Biochar – pyrolysis of biomass, with carbon capture and storage

PEC biomass can also be used in combined heat and power plants and biomass boilers at a variety of scales. The market for the biomass produced from PECs is relatively immature in Scotland. There are several biomass energy plants ranging in size from large scale industrial units and power stations to small units supplying individual farms. These mostly utilise wood from local forests, waste wood from Scotland sawmills and other industries so the market for further PEC biomass is currently limited[4]. Scotland’s largest wood-fuelled power station, is located in Markinch, with 55MW capacity utilising mostly recovered wood, some virgin wood chip. The next biggest is Steven’s Croft, in Lockerbie which generates 44MW of electricity and 6MW of heat which initially planned to source fuel from local forests (60%), SRC willow (20%) grown within a 60-mile radius (and requiring around 4,000 hectares land) and recycled wood fibre (20%) (Warren et al., 2016), but the latest data suggests it mostly uses a mix of wood and waste wood[5]. BECCS plants are not expected to deploy in Scotland until 2030.

Evaluating economic potential of PEC in Scotland

To understand the real potential, it is critical to consider not just the overall economic viability of PECs, but also how the demand for land for PECs can be balanced against, or integrated with other uses such as food and fodder production and biodiversity, and the skills, knowledge and attitudes of the farmers or land managers.

The economic potential of energy crops

A Rapid Evidence Assessment (REA) seeking evidence of the economic potential of energy crops in Scotland was undertaken and identified peer-reviewed and grey literature. The methodology can be found in Appendix C. The review focused on Miscanthus, SRC and SRF to specifically identify:

  • The positive and negative economic potential of energy crops.
  • Other (non-economic) opportunities and barriers to deployment.
  • Further economic potential (e.g., in relation to employment; technologies; wider decarbonisation, just transition).

Key insights are presented here, along with relevant insights from the stakeholder research. For full details of information found in the literature review and references to information sources (please see Appendix d), for details of stakeholder interviews conducted see Appendix G.

Key findings of the rapid evidence assessment and stakeholder engagement 

Evidence of positive economic potential

  • There is evidence that PECs can be profitable, but there are limited studies directly applicable to Scotland and to the current economic climate (Appendix D: 15.1)
  • Economic performance of biomass production is influenced by production costs, crop yields, crop price and end-use/market opportunities. (Appendix D: 15.1)
  • Several studies comparing energy crops reported a high return per hectare for miscanthus primarily due to low maintenance cost along with the low requirement for field operations. (Appendix D: 15.1)
  • The tree species chosen for SRF influences plantation establishment costs and therefore profitability as costs vary between species. Initial indications from trials underway in Scotland suggest hybrid apsen to have most potential, with common alder, silver birch and Sitka spruce having potential at some sites. (Appendix D: 15.1)

Evidence of negative economic impacts

  • The most prominent evidence of negative economic impacts in the literature was the high upfront cost to establish PECs, lack of established markets, and the uncertainty over the stability of the long-term market. (Appendix D: 15.2)
  • Profitability and economic considerations for farmers are dominated by high establishment costs, uncertainties about the market, a delayed period of revenue, and biomass yield. (Appendix D: 15.2)

Economic potential of PECs in comparison to other land uses

  • The literature review did not provide clear evidence of how the three key PECs compare economically to other crops, annual crops and agricultural land-uses – some studies showed favourable comparison and others did not. Limited insights can be gained from the literature given the recent economic changes affecting agricultural costs and market prices (Appendix D: 15.3)

Influences on decisions to plant PECs

  • One of the main factors affecting the uptake of PEC is economic profitability (Appendix D: 15.4)
  • Appetite for and perception of financial risk, skills, attitudes and access to markets can influence farmer and land-manager decisions. (Appendix D: 15.4)
  • Even where PECs, or energy crops in general, can deliver positive economic results for farmers and land managers, this on its own is not always sufficient to convince them to start growing PECs. (Appendix D: 15.4)

Other features of PEC production that influence economic potential

  • Producing PECs has specific economic implications for growers which influence their economic potential and attractiveness. These include lack of flexibility of land-use, reduced market responsiveness, and opportunities for diversification alongside current farming enterprises. (Appendix D: 15.5)
  • To view PECs as economically worthwhile, farmers need confidence that they can achieve an acceptable and secure market price into the future. As farms typically operate in a risk-averse manner, reduced risk is an important factor in farmer decision-making for PECs. (Appendix D: 15.5)
  • The way PECs are deployed on farms influences their economic potential. Integration of PECs alongside other enterprises and on land which is not performing well could be advantageous. (Appendix D: 15.5)

Opportunities to improve economic potential

  • Cultivation techniques, crop variety choice and other technological developments can influence economic potential of PECs in Scotland and have potential to improve profitability for farmers and land managers in future. (Appendix D: 15.6)
  • There are factors which can negatively affect the economics of PEC production, which if addressed are potential opportunities to improve economic performance. (Appendix D: 15.6)
  • Gaps in the crop (i.e. patches where it didn’t grow) was a key factor reducing profitability of miscanthus in the UK.
  • Ensuring access and enabling harvesting equipment is essential for economics of SRF to be viable
  • For SRF effective plantation establishment is important for the economics and general success of a SRF plantation
  • Single species monocultures can offer greatest economic return by providing higher yields per hectare
  • Highest yield are achieved on fertile soil or under intensive management systems, including weed control, fertilizer application and irrigation

Evidence of potential for wider economy

  • There was limited research addressing the potential contribution to the wider Scottish economy and a just transition, but some opportunities and challenges can be inferred. These include sales for local energy generation and other industrial uses, employment opportunities in contract services, along with potential payments for environmental outcomes. (Appendix D: 15.7)

Evidence of non-economic opportunities

  • Non-economic opportunities and benefits of PECs were identified including several relating to positive environmental outcomes such as reduced agro-chemical use, reduced soil and water pollution, carbon sequestration, and biodiversity benefits. (Appendix D: 15.8)
  • The opportunities for environmental improvements resulting from PECs vary depending on planting, prior land-use and landscape context. (Appendix D: 15.8)

Challenges and deployment barriers

  • Non-economic challenges facing the production of PECs in Scotland, relate to skills, land-use commitment, compatibility with current culture and habits, farm businesses, perceived land suitability and environmental concerns. (Appendix D: 15.9)
  • Deployment barriers include the need for farmers to commit land for a long period of time, land quality, knowledge, profitability, time to financial return and social resistance relating to whether land should be used for energy or food production. In addition for SRC and SRF, converting land once planted is challenging, and additionally for SRF conversion be restricted by regulations as land will no longer be classed as agricultural. (Appendix D: 15.9)
  • Lack of access to specialist skills and to specialist contractors and machinery was identified as a barrier to deployment. While there is interest amongst farmers in diversification, appetite for change is tempered by concern about moving into unfamiliar activities which require new skills.
  • Culture and attitudes can be a barrier to PEC deployment. (Appendix D: 15.9)
  • There are concerns about the impact on biodiversity from PECs. (Appendix D: 15.9)
  • Energy generation from biomass is a potential source of direct and indirect emissions and limiting these emissions would need consideration. (Appendix D: 15.9)

Other relevant crops and planting regimes

  • Hemp has the potential to provide high yields or returns with little or no pesticides and insecticides, significant potential in carbon sequestration, fits well into crop rotations with food and feed crops and helps improve soil structure and soil-borne pests. Constraints on producing hemp in Scotland includes the current lack of market as there are no large processing facilities in or near Scotland, strict regulations on growing hemp including the need to obtain a costly license, and some reports of low profitability according to Scottish growers. (Appendix D: 15.10)
  • Specific studies focused on Scotland to show how PECs could be grown in agroforestry systems were not found, but provided the design of agroforestry systems can allow for economically efficient planting, management and harvesting it could provide an advantageous model. (Appendix D: 15.10)

Key evidence gaps

The research found some uncertainties – due to lack of Scottish specific data and in relation to climate impacts on PECs – which are described in the relevant sections above, and also some key gaps in the evidence which are summarised here.

Lack of Scottish data and research leading to economic uncertainty

Research related to the production and economic potential of energy crops in Scotland is limited. SRC is currently grown, but only at a small scale, and miscanthus still requires further trials and research before implementing at a commercial scale. SRF trials are currently underway in Scotland with findings slowly emerging as plantations reach maturity (Parratt, 2017). There is therefore uncertainty regarding the economic potential in Scotland.

The literature is inconclusive regarding the financial performance of PEC production. Conflicting results are found across studies, for example, a study in Ireland found miscanthus production to be an economically viable option (Zimmermann et al., 2014), yet in France, Miscanthus was found to be less profitable compared to conventional cropping systems (Glithero et al., 2013). Research by Warren (2014) reported that the soils and climate across Scotland offer significant biophysical potential, especially for SRC willow cultivation, which can also achieve good growth rates. However, with such limited data on Scotland and in light of the less favourable climate than found in locations of many studies there is uncertainty about the economic viability in Scotland.

Climate change

The effects of climate change on PECs are to some extent unknown. Research suggests that SRC willow yield may reduce as a result of rising temperatures, while miscanthus performs favourably (Alexander et al., 2014). However, as the temperature rises, this may change the habitat suitability, further research is required to establish the suitability and risks that a changing climate may have on seed development in miscanthus throughout the UK (Martin et al., 2020). We did not find research which commented on how extreme weather such as storms, flooding and drought would affect PECs. Some research suggests that water-logged soils hinder growth of PECs (Martin et al, 2020), but a recent technical webinar from Biomass Connect suggested that willow SRC is not negatively affected by water-logging, and can help improve water management when established.

Active debates within the sector

It is evident from the literature and stakeholder interviews that there are some topics with differing views including what types of land are most suitable for PEC growing considering the wider land-use debates, and likely impacts on biodiversity.

Land use and use of unproductive areas of land

In Scotland, there is competition for land to deliver food, materials, environmental services (such as carbon sequestration), leisure opportunities and more (Martin et al., 2020; Scottish Government, 2021). Scotland has the potential to produce 9.25TWh/yr and 1.75Modt/yr for SRC (Martin et al., 2020) such as SRC willow, however amongst the farming community there is social resistance relating to land being used for energy instead of food production (Anejionu and Woods 2019). The Scottish Government’s Land-use Strategy (Scottish Government, 2021) highlights the complexity of balancing the need for land to support the move to net zero with other essential activities such as food production, and that whilst land-use decisions are often determined by the land suitability, much land is suited to multiple different uses. In these cases multiple factors need to be considered as to whether PECs are a suitable use for the land.

Literature identifies that using ‘marginal’ land, for energy crop production could be a solution to this land use debate. However, there are several challenges in understanding whether this ‘solution’ could usefully apply in Scotland. Ranacher et al., 2021 found there is a gap in the available literature regarding farmers’ willingness to adopt short rotation plantations on marginal lands. There is also no agreed definition in the literature of what comprises ‘marginal’ land, so it is unclear how this would apply in the Scottish context. Much discussion in research focuses on cropland, yet in Scotland grasslands including rough grasslands, which may be viewed as ‘marginal’ from some perspectives, are a critical part of the Scottish rural economy and environment and so a more indepth analysis of the potential social, environmental and economic implications of PECs on grasslands is needed. Additionally, not all literature agrees on whether PECS will successfully grow on marginal land.

Biodiversity & ecosystem services

Converting land to energy production in Scotland will have direct impacts on biodiversity, wildlife, and landscape connectivity, yet the exact nature of these is unclear from the literature. Research shows that bioenergy crop choice and location influence biodiversity outcomes – choosing appropriate bioenergy crops in the right location is vital for the protection of biodiversity and ecosystems and to prevent damage to the surrounding ecosystem.[6] Contradictory evidence has been found throughout the REA on the effects of converting land for energy crop production in Scotland. Existing sustainability criteria for the use of biomass to produce heat or electricity require that PECs are not grown on land of high biodiversity value[7]. Beyond application of these criteria, the research could create uncertainty about how to select the right crops for the right locations in Scotland to ensure good outcomes for biodiversity and ecosystem services. Extrapolation of potential biodiversity effects from conversion of ‘marginal’ land has low confidence (Holland, et al., 2015) (Vanbeverena & Ceulemansa, 2019), and application of this research to the Scottish context with different land-use types is therefore very difficult.

The impact on biodiversity from SRC, SRF and Miscanthus differ depending on location, previous land use and crop type and management (e.g., cultivations, pesticide, and fertiliser use). The replacement of any semi-natural habitat by a dedicated bioenergy crop is likely to result in significant biodiversity losses due to creating a monoculture habitat (Martin et al., 2020). Significant areas of land classified as ‘Less Favoured Areas’ (LFA) in Scotland which were identified as potential PEC growing areas could be described as semi-natural – and seen as ‘marginal’ – but there is a risk of biodiversity loss if this is converted to PEC.

The REA identified a conflict in opinion as to whether PECs provide a biodiversity gain or loss. Firstly, factors such as reduced ground disturbance, increased diversity of nectar and pollen sources, and the potential to provide over wintering sites which are associated with energy crop production will benefit pollinating species. Conversely the monoculture nature of energy crops is likely to be detrimental to pollinator species as landscape homogenisation is widely accepted to be a driver for the current loss of pollinating species (Martin et al., 2020). Holland et al. (2015) identified ecosystem services such as hazard regulation, disease and pest control, water, and soil quality may benefit from the conversion of arable land to energy crop production, and that the transition of marginal land[8][9] to bioenergy crops will likely deliver benefits for some ecosystem services while remaining broadly neutral for others. On the other hand, conversion of forest to energy crops will likely have a negative impact due to the increased disturbance associated with the management cycle.

Estimating economic potential

This research looked at perennial energy crops (PECs), SRF, SRC and Miscanthus and included two core economic analyses:

  • Farm-scale economic analysis and comparison with typical land-use options:
  • A farm scale economic analysis of the net economic benefit for a farmer or land-manager from producing and selling the Miscanthus, SRC and SRF.
  • A comparison of this net economic benefit for a farmer or land-manager with typical existing land-uses.
  • Assessment of wider economic implications: drawing on geo-spatial data about existing farming and land-use types, the study analysed what the economics implications would be for the wider Scottish economy of a transition to growing more energy crops.

Farm Scale Economic Analysis

Methodology overview

  • For the farm-scale economic analysis high, medium and low-cost scenarios were developed for the production costs for: Miscanthus; short rotation coppice: willow; short rotation forestry: conifer; and short rotation forestry: broadleaved. The higher scenario includes high output/high price minus low costs, the medium scenario scenario includes medium output/medium price minus medium costs and the low scenario includes low output/low price minus high costs.
  • The following production costs were included; pre-planting/land preparation, planting, post-planting, harvesting and storage and reversion.
  • Capital investment costs were not included: where specialist equipment would be needed, which a farmer would not typically have on a farm, such as cutting equipment for SRF, we have assumed services of a specialist contractor would be utilised and this cost has been included within the production costs.
  • Estimates of likely income from PEC sales were combined with costs to create a ‘gross margin[10] (income minus costs) for each bioenergy crop. Because the PECs all have a long lifespan, time series charts are used to show the income minus costs over the lifetime of the crop. The results of which can be found in section 5.1.3. Depending on the crop, the yield changes over the lifespan of the rotation, for example due to lower yields in early years after establishment and harvest only occurring in some years. Details on the yields during rotation can be found in Appendix D. For Miscanthus and SRF a low, medium and high price presented, whereas for SRC a single price is used due to limited data. Prices used in the analysis are in Appendix D.
  • To compare to the economics of current land use, three farm types were used these were lowland cattle and sheep; mixed farming[11]; and general cropping – forage. These were selected because they are feasible on the land capability of grades; 4.1, 4.2, 5.1, 5.2, 5.3 and 6.1, – typically suitable for mixed agriculture, improved grassland and high-quality rough grazing, and also the land capability grades assumed suitable for PECs . To calculate the gross margins for the farm types used in the analysis the latest data from the ‘Scottish farm business income: annual estimates 2020-2021’ were used[12].
  • Subsidies are not included in this analysis.
  • Total average output in the farm business survey[13] includes the output categories; total crop output, total livestock output and miscellaneous output. For the ‘general cropping – forage’ category census data is used and output represents the estimated farm-gate worth (£s) of crops and animals without taking account of the costs incurred in production.

A more detailed description the methodology used, assumptions and data sources is included in Appendix E.

Limitations with the methodology

The calculations for the farm types used in the analysis are based on data from the Scotland Farm Business Income Survey, therefore the estimates are based on averages and so any other factors that might influence the costs and output for example climate, soil type will not be accounted for. This is the same for the costs and output estimates for the bioenergy crops. We have not allocated an economic value to any additional benefits a farmer may gain for the other farm enterprises, such as shelter for livestock on adjacent land.

It should also be noted that this study focused on gross margin comparison, which is useful for comparing specific crops and farm enterprises, but has limitations in terms of how well it allows assessment of integration of energy crops into a whole farm business. This will vary farm to farm and would require more in depth ‘whole farm’ economic analysis to be fully understood.

 

Results of Farm Scale Economic Analysis

Figure 5‑1 shows what land managers could earn on average in a year if costs and yield were spread equally over the lifecycle of the bioenergy crop as well as for farm types (for full details on the method please see Appendix E). There are gross margins for a low, medium and high scenario for each of the bioenergy crops and for the farm types (except for general cropping, forage[14]). The low, medium and high scenario for lowland cattle and sheep and mixed farming includes the lower (25%), average and upper (25%) of data from the farm business income data respectively, average data from 6 years 2016-17 to 2021-22 uprate to reflect 2023 prices[15].

Figure 5-1 ‑Yearly average gross margins for each of the PECs over the lifetime of the PEC and for each farm type £/ha (2023 prices)

If costs and income were spread equally over the lifetime of the crop, the medium scenario suggests:

  • Miscanthus produces a positive average annual gross margin of £382 per hectare, SRC £87 per hectare and SRF broadleaved £80 per hectare.
  • SRF conifer would see a negative gross margin i.e., the production costs outweigh the value of the crop sold. The planting and the ground preparation costs are the main drivers behind this negative gross margin (see Appendix D for more detailed costs).
  • Mixed farming and and lowland cattle and sheep farms both show a greater average annual gross margin than all of the PECs examined.
  • The average gross margin per year for general cropping, forage is negative at around £990 per hectare, significantly lower than for all of the PECs. Based on these average annual gross margins, growing PECs in lowland cattle and sheep and mixed farming would reduce financial returns in the farm. Whereas, growing PECs in farms in the general cropping forage category could improve their financial returns.

Figure 5‑2, Figure 5-3, Figure 5-4, Figure 5-5 shows the low, medium and high scenario gross margins (output minus variable costs) over time of each of the PECs: Miscanthus, SRC, SRF broadleaved (silver birch) and SRF conifer (Sitka spruce). The higher scenario includes high output/high price minus low costs, the medium scenario includes the medium output/medium price minus medium costs and the lower scenario includes low output/low price minus high costs.

Costs included in the calculations included:

  • Site preparation / land preparation (including from different prior land-uses where data is available)
  • Establishment / planting
  • Crop management costs e.g., during initial growth
  • Harvesting
  • Reversion (where relevant)

Detailed breakdowns of these costs for the PECs are included in Appendix E.

Figure 5-2 Gross margins for Miscanthus (£/ha) (2023 prices)

  • Miscanthus shows an initial negative gross margin in the first two years during the site preparation and plant stages, but then picks up in the following years with harvesting driving the positive gross margins in the following years. The gross margin drops slightly in the year 21 when the costs of reversion take place.

Figure 5-3 Gross margins for short rotation coppice (£/ha) (2023 prices)

  • Short rotation coppice shows a negative gross margin for the first 3 years, in part driven by the pre-planting/land preparation costs in years -1 and 0. Gross margin is then positive in the years 3, 6, 9, 12, 15 and 18 reflecting when harvesting takes place.

Figure 5-4 Gross margins for short rotation forestry – Sitka Spruce (£/ha) (2023 prices)

Figure 5-5 Gross margins for short rotation forestry – Silver Birch (£/ha) (2023 prices)

  • Short rotation forestry for silver birch and Sitka spruce shows a negative gross margin except for the year 15 when harvesting takes place.

Linking back to Figure 5-1 with the lowland cattle and sheep category on average earning £433 per hectare per year, the mixed farming category £597 per hectare per year and the general forage making a loss of £990 per ha per year the results show;

  • Miscanthus, initially has a lower gross margin than all the other farm types, however, after the first few years, land managers would be better off planting Miscanthus.
  • SRC, produces a better gross margin than general cropping-forage after the first few years but is outperformed by all other categories when the yield is harvested in years five, eight, 11, 14, 17, 20 and 23.
  • SRF, again outperforms general cropping- forage, but has a lower gross margin than the other farm types, except for when harvest takes place in year 18.

Assessment of implications for Scotland’s rural economy

To consider the potential implications of growing more PECs, the results from the farm-scale economic analysis (Section 5.1) were extrapolated across Scottish regions, to consider a transition of approximately 40,000 to 90,000 hectares of suitable land to grow PECs – the area judged to be feasible by 2032 and 2045 respectively (see below for the source of these estimates).

Key findings:

This transition of land in mixed holdings and non-LFA cattle and sheep to PECs would create a shortfall of non-energy crops and and reduced income across the Scottish rural economy due. Because PECs would be more profitable than ‘general cropping: forage’ land-use, there would be an economic gain from transition, but loss of production of animal feed, which may have knock-on implications for livestock production costs (which have not been quantified here).

This research found that, if land to match the level of demand as set out in these scenarios, was utilised for perennial energy crops it would create:

  • a gain in gross margin[16] of around £9.6 million (scenario 1) or a loss of around £9.5 million (scenario 2) per year across the regions.[17]
  • a shortfall in agricultural yields (of farm outputs generated by existing land-use activity, which would not be available when the activity ceased to be replaced with PECs) across the regions between 537,600 tonnes (scenario 1) and 708,200 tonnes (scenario 2).

Our analysis which forms the basis of this assessment is set out below – with details of each scenario (approximately 40,000 and 90,000 hectares).

Limitations:

This assessment does not consider potential loss or additions to the economy due to changes in associated services. Some additional contracting employment for PECs servicing is likely based on the research, but this, and any potential shortfall in other employment from reducing other farm enterprises have not been assessed.

It should also be noted that the findings relate solely to gross margin comparison. Actual farm income – whole farm business income – is very different, comprising multiple farm enterprises (livestock, crops, diversifications) and may be supplemented with off-farm income. For the farm types considered here typical farm income levels are shown in Table 5-1 below (note General Cropping, Forage is not a type assessed in the Scottish Farm Business Income Survey so data is not available). Assessment of implications for PECs on the overall farm costs and income has not been fully assessed here and may reveal additional positive and negative economic implications of PECs.

Table 5-1: Annual Farm Business Income (£) (average of 6 years 2016-17 to 2021-2022)

 

Farm total

Per hectare

Farm Type

Lower (25%)

Average

Upper (25%)

Lower (25%)

Average

Upper (25%)

Mixed Farming

-9271

37,791

129,023

-58

225

551

Lowland Sheep & Cattle (non-LFA)

-20,688

25,756

105,926

-176

191

451

Method and results

For each of non-LFA cattle & sheep, mixed holdings, general cropping; forage, areas that would be suitable to grow PECs have been identified (see Table 5-1). (See Appendix E for further details on how these areas were selected.) This was done by using the GIS mapping done in previous work for CxC (Martin et al,2020) which identified land suitable for PECs to identify the percentage of land in region which was suitable for PECs. This percentage was then applied to the land area estimated to be in each farm type in the region, to derive the land are potentially suitable for PECs by farm type. There is some overlap between the types of land suitable for each of the three types of PECs so the areas in the table cannot be summed to give a total area.

Table 5-1 Potential land suitable for each bioenergy crop on different farm types (hectares)

 

General Cropping, Forage

Non-LFA Cattle & Sheep

Mixed Holdings

Total

(all farm types)

Land potentially suitable for SRF

13,601

66,189

27,746

107,536

Land potentially suitable for SRC

7,967

50,520

20,156

78,643

Land potentially suitable for Miscanthus

1,352

12,633

4,770

18,755

A previous CXC study (Meek et al, 2022) indicated that, bearing in mind land suitability, an estimated total of approximately 27,000 ha PECs[18] could be planted by 2030, 38,000 by 2032 and 90,250 hectares by 2045. Using these estimates and the potential land that can grow bioenergy crops two illustrative scenarios have been created to estimate the potential economic gain/loss of growing bioenergy crops at the Scottish level.

Scenario 1:

From the results presented in section 5.1 it was financially beneficial to grow bioenergy crops on general cropping, forage land. Furthermore, of all the PECs, growing miscanthus was the most financially beneficial. Therefore, the first scenario assumes that two-thirds (66%) of the general cropping, forage land suitable for SRF and for SRC will be converted and 100% for Miscanthus. Only 66% of land for SRF and SRC are assumed to be converted to avoid double counting due to the likelihood that some areas identified are suitable for both PECs and thus appear in both estimates of suitable areas. Although the results in section 5.1 show that growing bioenergy crops on both non-LFA cattle and sheep and mixed holdings would not be financially beneficial, the loss was less on non-LFA cattle and sheep land. Therefore, to get to the 38,000 hectares, it was assumed that 15% of the land suitable for both SRF and SRC in non-LFA cattle and sheep holdings will be converted and 30% for Miscanthus (see Table 5-2). Overall this means that about 20% of total land in Non-LFA Cattle and Sheep[19] and 1.1% of land in general cropping, forage are converted to PECs.

Table 5-2 Land that is converted for each bioenergy crop for each farm type in scenario 1 (hectares)

 

General Cropping, Forage

Non-LFA Cattle & Sheep

Mixed Holdings

Total
(all farm types)

SRF

8,977

9,928

18,905

SRC

5,258

7,578

12,836

Miscanthus

1,352

3,790

5,142

Total (all PECs)

15,587

21,296

36,883

Total land in farm type in Scotland

1,378,365

107,712

304,901

1,790,978

Percentage of total area converted

1.1%

20%

0%

2.1%

Results: scenario 1

Figure 5-6, shows that, for Scenario 1 there would be an economic gain for converting land used for general cropping and forage to PECs. This is because PECs have a positive, albeit small gross margin, compared to the large negative gross margin for general cropping and forage. The total gain in gross margins across the region is around £16.6 million, of which almost half occurs in Grampian.

Figure 5-6 Change in gross margin for converting General Cropping, Forage land to Miscanthus, SRC and SRF (Scenario 1)

Figure 5-7, shows there would be potential economic loss for converting non-LFA cattle and sheep land to Miscanthus, SRC and SRF in table 5-2 (scenario 1) with Grampian showing a loss of a total of about £1.8 million. SRF showed the greatest loss in the majority of the regions, as it has the lowest gross margin of all the PECs but has more land suitable for it. Miscanthus showed the smallest loss across all regions. The total loss in gross margins across regions is just under £7 million. This loss is lower than the gain in gross margin from growing PECs on general cropping and forage farms, suggesting that achieving 38,000 ha of PECs could give a net increase in gross margins across the two farm categories of £9.6 million.

Figure 5-6 Change in gross margin from converting Non-LFA Cattle and Sheep land to Miscanthus, SRC and SRF (Scenario 1)

Figure 5-8 shows the reduction in production (crops, stock-feeding crops and grass from grazing land) that could occur when converting the land shown in Table 5-2 to PECs. From converting land to PECs, there is an estimated yield loss of 537,600 tonnes: 263,000 tonnes for crops replaced by with SRF, 85,300 tonnes for crops replaced by Miscanthus and 189,000 tonnes for crops replaced with SRC.

Figure 5-8 Reduction in production (barley, stock-feeding crops and grass) resulting from converting land to PECs (thousand tonnes) (Scenario 1)

Scenario 2:

For the second scenario to get to around 90,000 hectares of land, it was assumed that more of the suitable general cropping and forage land was converted to SRF and SRC (66%), and more of the non-LFA cattle and sheep land (30% of land suitable for SRF and SRC and 60% of land suitable for Miscanthus). It was assumed that a small percentage of the suitable land on mixed holdings was converted (50% of land suitable for SRF and SRC and 50% of land suitable for Miscanthus). Overall, this means that about 40% of the total land in non-LFA cattle and sheep farms, around 9% of total mixed holdings and 1.3% of total general cropping /forage land are converted to PECs.

Table 5-3 Land that is converted for each bioenergy crop for each farm type in scenario two (hectares) (Scenario 2)

 

General Cropping, Forage

Non-LFA Cattle & Sheep

Mixed Holdings

Total (all farm types)

SRF

10,201

19,857

13,873

43,931

SRC

5,975

15,156

10,078

31,209

Miscanthus

1,352

7,580

4,770

13,701

Total (all PECs)

17,528

42,592

28,721

88,841

Total land in farm type in Scotland

1,378,365

107,712

304,901

1,790,978

Percentage of total area converted

1.3%

40%

9%

5%

Results: scenario 2

Figure 5-9, show the results of the conversion rates set out in table 5-3 (scenario 2). The only farm type which shows an increase in gross margin for conversion to PECs is general cropping and forage (due to its current large negative gross margin). Conversions on the other farm types (necessary to meet the target planting area of around 90,000 ha) give a loss in gross margins. Overall, the increase in income in general and cropping farms of £18.6 million is not enough to offset losses in the other two farm types, (£13.9 million in non-LFA cattle and sheep farms and £14. 2 million on mixed holdings) meaning there is a net loss in gross margin of £9.5 million.

Figure 5-9 Change in gross margins from converting Non-LFA Cattle and Sheep land to Miscanthus, SRC and SRF (Scenario 2)

Figure 5-10 shows the crop production that could potentially be lost from converting the land shown in table 5-3 (scenario 2) to PECs. This based on loss of stock feeding crops (barley, maize and lupin) and grass silage and hay produced on each farm type. From converting land to PECs, there is estimated yield loss of 708,200 tonnes for replacing with SRF, 248,100 tonnes for replacing with Miscanthus and 523,900 tonnes for replacing with SRC.

Figure 5-10 Reduction in crop production (barley, stock-feeding crops and grass) resulting from converting land to PECs (thousand tonnes) (Scenario 2)

Preferred locations: considerations

Preferred locations for economically viable production of PECs are influenced by multiple factors including proximity to markets (current biomass energy plants and potential future BECCS plants) and local enough access to services and facilities for crop management (e.g. harvesting contractors) to avoid excessive costs. We assessed preferred locations for economically viable energy crops in Scotland considering the locations of end markets in relation to viable growing areas for PECs.[20]. Insights from our rapid evidence assessment and stakeholder consultation were also considered, for example comments on economically viable transport distance.

Our analysis showed economically viable areas for PEC production bearing in mind future anticipated demand resulting from Scotland’s net zero ambitions, but only SRF could provide quantity needed, due to lack of availability of suitable land for SRC and miscanthus. As SRF is economically uncompetitive against current land-use, this suggests economic viability may be a barrier to PEC production increases even if suitable land within economically viable distance of end markets is available.

Proximity to users of biomass for energy

Biomass energy crops are bulky to transport and so haulage cost from the location where they are grown to where they are used is a factor which determines which growing locations are economically viable – a crop grown too far from its end destination will be prohibitively expensive to transport. It has been difficult to identify a specific economically viable distance in the available research. Stakeholder comments suggest that whilst 100km is a typical maximum distance to haul wood to a sawmill, a significantly lower distance is economic for biomass crops, as their value is lower than wood which will become sawn timber. In our economic analysis transport costs pre-farm gate e.g. for delivery of planting material are included, but haulage of the bioenergy crops to biomass plants has not been included in the costs as this will depend on the distance and whether the price paid to the farmer is at the farm gate or at delivery to the bioenergy plant. For the purposes of the analysis here, we assume a maximum viable distance of 100km, and consider a shorter 50km distance to reflect stakeholder feedback.

Proximity to existing biomass plants:

Biomass plants in Scotland were identified from DESNZ’ Renewable Energy Planning database which lists both existing and planned plants[21]. Existing sites vary in scale and use – some are generating power for the grid, others are located on industrial sites such as distilleries, sawmills and papermills supplying heat and power for the industry, whilst others are small supplying e.g. a hotel. Eight sites were selected from the list as being most likely to consider using PECs as a fuel (See Appendix J). Plant which are located on sites where there is already a ready supply of fuel (e.g. sawmills, paper and pulp) were excluded as were very small sites and sites which were not yet operational or under construction.

A buffer of 50km and 100km from these biomass plants has been applied in Figure 6-1, to show the potential geographical areas which could supply biomass markets in Scotland.

Figure 6-1: Biomass plant locations

Map of Scotland showing a zone of 50km and 100km around  locations of main biomass plants and the locations of potential biomass growing locations.

Proximity to future BECCS facilities:

CCC[22] highlights that Scotland has very good potential for deploying Bioenergy with Carbon Capture and Storage (BECCS) due to its access to a potential CO2 storage site in the North Sea, along with its ability to produce domestic BECCS feedstocks. A pilot facility, the Acorn Transport and Storage Facility in Aberdeenshire looks set for further investment after the UK government announced in March 2023 that it considers this site to be one of the two best placed to deliver its objective of capturing 20-30 megatonnes of CO2 across the UK economy by 2030[23]. The proposed access points to this facility are via a feeder pipeline along Scotland’s east coast which starts at Bathgate and ends at St Fergus, with two injection points at Kirriemuir and Garlogie. Large scale BECCS plants for electricity, biomass gasification for hydrogen, or biofuel production[24] may be located in proximity to these access points to benefit from easy access to the pipeline. This study assesses how much land suitable for growing bioenergy crops is within 50km and 100km of these access points. This mapping is presented in Figure 6-2.

Kirriemuir

St. Fergus

Garlogie

Bathgate

Figure 6-2 Feeder pipeline locations and nearby land suitable for PECs

Table 6-1 shows the total potential PEC growing areas with these distances.

A previous CXC study (Meek et al, 2022) indicated that, bearing in mind land suitability, an estimated total of approximately 27,000 ha PECs[25] could be planted by 2030 and 38,000 by 2032; With this area of land, depending on the yields obtained for PECs and the efficiency of the power plant, PECs could provide feedstock for a BECCs power plant producing between 60 and 80 MWe. The data in Table 6-1 suggests that this land is available, within 50km of all proposed access points along the east coast feeder pipeline for SRC and Miscanthus, but this would require a large portion of the suitable land to be used. A larger land area which is suitable for growing SRF is available.

Table 6-1: Total potential PEC growing areas within 50km and 100km of potential BECCS sites, and existing biomass plant locations.

 

Feeder pipeline locations

Biomass plant locations

 

Within 50km

Within 100km

Within 50km

Within 100km

SRC

82,471 ha

161,016 ha

117,222 ha

225,013 ha

Miscanthus

8,224 ha

18,057 ha

18,280 ha

28,873 ha

SRF

551,303 ha

826,528 ha

555,193 ha

858,669 ha

Access to service and facilities for crop management, harvesting and processing.

Access to services and facilities for crop management harvesting and processing, such as local contractors with suitable equipment has been identified in the research and by stakeholders as a factor which would influence the suitability of growing areas for PACs. The evidence review did not provide information on the availability and access to these services in Scotland, or the speed with which services could develop if a growth in production were planned. Easy access should not be assumed, particularly given the shortage of forestry skills in Scotland and constraint on travel distance which influence the economic viability – access issues would need to be addressed before an area could be suitable for economically viable PEC growing.

Other location considerations

As is evident from the REA, biodiversity and other ecosystem services can impacted by PEC cultivation. Choice of crop, cultivation regime and location need to be carefully considered to optimise environmental benefits and avoid negative impacts. The impact is highly situation specific and could not be assessed in detail within scope of this research but should be considered carefully when selecting locations.

SWOT & PESTLE Analysis

This section provides analysis of the strengths and weaknesses of these crops, and the factors supporting or hindering uptake, drawing together the research findings. A PESTLE analysis was also carried to understand the potential enabling and preventative factors which could influence the economic viability of energy crops in Scotland. Further detailed SWOT and PESTLE analyses are available in Appendix I.

SWOT Analysis of energy crop economic potential

Table 7-1 presents SWOT analysis common to PECs assessed in this research. Further discussion of variations between Miscanthus, SRC and SRF is included in Section 9.

Table 7-1: Summary of strengths, weaknesses, opportunities and threats for PEC in Scotland.

Strengths

Weaknesses

  • Feasible growing areas including proximity to potential BECCS sites (varies by crop)
  • Low input & maintenance costs
  • Alternative markets beyond energy (e.g. Miscanthus for animal bedding; SRF grow on for other wood products)
  • Stable annual income if sequentially planted
  • Shading benefits for adjacent land
  • Cash flow- upfront cost to establish crops, and several years before first harvest income
  • Lack of specific subsidies / financial support for energy crops.
  • Need for specialist knowledge and equipment – access constraints
  • Lack of processing facilities
  • Biomass cost currently compares unfavourable to fossil fuels
  • Biomass for energy is a lower value crop than sawmill wood / biomass for other industries (such as bio-based plastics)[26]
  • Limits farmer land-use rotation choices
  • Costs of transport for bulky crop – constrains distance from end market
  • Shading disadvantage for adjacent crop.

Opportunities

Threats

  • Income diversification: potential additional revenue stream with limited workload after establishment.
  • To design PEC planting to deliver additional environmental benefits such as water management, biodiversity, soil health.
  • To improve farm energy security/costs by use of biomass on farms
  • To harness innovation pipeline and developing knowledge base to increase yields / cut costs (see Appendix H)
  • Contractor services employment e.g., establishment / harvest.
  • Uncertain/under-developed end market
  • Uncertain future market price
  • Competition from cheaper imported biomass
  • Potential competition between different Scottish users (e.g., on farm vs BECCS)
  • Public / NGO negative perceptions
  • Farmer/land-manager preferences for current land-use and perception of PECs as financially risky.
  • Limited geographical spread of contractors.

PESTLE Analysis

The PESTLE analysis considersthe political, economic, social technical, legal and environmental factors which currently enable or prevent energy crops becoming an economically viable prospect for farmers in Scotland. The summary PESTLE is set out in Table 7-2 below, discussion of the results follows in Section 9.

Table 7.2: Summary of PESTLE analysis for growing PECs in Scotland.

 

Enabling factors 

Preventative factors  

Political 

  • Political support by Scottish / UK government –identified as critical to climate goals.  
  • Uncertainty of specific policies/ government financial support. 
  • Limited grant funding opportunities for farmers and land-managers. 

Economic 

  • Low input costs / labour costs once established. 
  • Income diversification opportunity / additional income stream if planted on previous unproductive land. 
  • Machinery innovation could cut costs of production. 
  • Large initial investment and lack of cash flow in years before first harvest. 
  • High production costs, compared to imported biomass. 
  • Uncertain markets and market prices
  • Low profitability over whole crop lifetime.

Social 

  • Potential for employment in contracting services (e.g. planting / harvesting). 
  • Perception of PEC as financially risky. 
  • Attitudes / preferences of farmers and land-manager – preferences for familiar farm enterprises. 
  • Concerns about competition for land / resources e.g. livestock farmers concern about loss of local feed crops. 
  • Moral concerns about PEC replacing other land-uses e.g. food crops. 
  • Negative publicity about energy crops. 
  • Age of farmers: older farmers may not be in business long-enough to see profits. 

Technical 

  • Potential to use existing harvesters for Miscanthus.
  • Production and harvesting technology improvements in the pipeline. 
  • BECCS is an emerging technology – no current plants in Scotland. 
  • Need for specialist machinery, especially for SRC/SRF, which is limited in Scotland.  
  • Interdependence between producers and bioenergy plant: concurrent development of market and supply is challenging. 

Legal 

  • Long-term contracts between end users and farmers can give confidence for investments. 
  •  SRF results in legal land-use category change – reversion to farming may be prevented in future. 
  • Some crops are subject to cultivation licences (e.g. Hemp, Eucalyptus). 
  • Long-term land-use decisions difficult for tenant farmers. 

Environmental 

  • Desire for ecosystem services which some PECs could deliver e.g. flood control. 
  • Agrochemical restrictions driving interest in low-input PECs 
  • Potential to increase soil carbon
  • Biodiversity / habitat benefits in some circumstances, but some uncertainty 
  • Concerns about biodiversity impacts of ‘monoculture’. 
  • Environmental benefits depend on sustainable production methods.
  • Right crop – right land is critical: carbon stored in soils could be released by planting on peaty soils / uplands areas.  
  • Limited suitable areas e.g. some reports state SRC cannot tolerate water-logged soils. 
  • Winter hardiness of Miscanthus a constraint for Scotland.
  • Future climate change favour Miscanthus. 

Discussion

The research and analysis show multiple positive and negative features of the PECs. The implications of these for economic viability of PECs in Scotland is discussed here.

Economic potential to farmers and land managers

Economic potential of PECs in Scotland for farmer and land managers

Overall, the economic analysis showed Miscanthus could be most profitable over the life cycle, but though SRC and SRF broadleaves appear to achieve lower profitability, there are larger areas suited to these crops and less uncertainty about their suitability to the Scottish climate.

Achievable biomass yields, which significantly influences economic viability, is still subject to some uncertainty as commercial growing and trials in Scotland are limited, particularly for SRF and Miscanthus. The analysis shows a significant difference between high, medium and low costs and income from the three PECs considered. It could be reasonably assumed that this level of uncertainty may lead to farmers and land-managers having low confidence to plant the crops. Forthcoming results of Scottish research trials and developments may improve confidence, for example Miscanthus varieties more suitable to Scotland’s climate are in development (see Appendix H) which could extend the range or improve yields in Scotland.

Equipment needs, and therefore costs and economic potential, vary for the different PECs:

Miscanthus can be harvested by typical harvesting equipment which an arable or mixed farmer would either own, or have easy access to via local contractors; whereas for SRC and SRF the equipment needs are more specialist, so requires significant investment or access to local contractors, which is currently constrained in Scotland.

The PESTLE analysis shows that, of the factors which are likely to prevent farmers and land-managers from currently viewing PECs as an attractive proposition and hinder the uptake across Scotland. The most important, are:

  • the low or negative income from the crops,
  • upfront investment requirement, and
  • uncertain market for the crops.

Stakeholder feedback suggested some approaches which may addressing these issues:

  • Financial support for farmers, land-managers and other necessary parts of the sector including to enable adoption of forthcoming innovations aimed at improving yields and cutting costs, such as new harvesting techniques and mobile machinery for processing materials on farms.
  • Fixed price and long-term contracts for future crops, at prices higher than production costs. However, given imported biomass and fossil fuels appear to be available at lower cost it is unlikely that end-users will find it feasible to offer attractively priced contracts.
  • Greater clarity over the likely environmental impacts in Scottish context – both local impacts such as on biodiversity and wider impacts for example indirect land-use change from competition for food / animal feed crops – and how to design of PEC planting in Scotland to maximise positive environmental benefits.

Locational and temporal issues

In terms of suitable and preferred locations for energy crop production in Scotland, as described in Section 6, the proximity to biomass markets (such as power plants) is a key determining factor. The research has shown that there are suitable growing regions, primarily for SRC and SRF within 50km to 100km of existing biomass plants, or potential sites for BECCS plants close to the proposed east coast feeder pipeline, which are likely to be the dominant market demand in a future, more mature biomass market aligned to the Scottish Governments climate ambition. There is some uncertainty about the economically viable distance to transport energy crops, with stakeholders suggesting it would be significantly less than the typical 100km for sawmill quality wood. The number of viable production areas with 50km of potential sites is lower, but they are most advantageous due to lower transport costs (and GHG emissions).

The study did not explore in detail the potential for on-farm use of biomass, but stakeholder consultation suggested this may be an economically viable alternative, particularly for farms not located close to a suitable biomass plant, and given the context of high energy costs. On farm use of PECs is not a negative emissions technology, as it is not feasible to apply carbon capture to small scale plants, but it would contribute to decarbonising agriculture if it replaced fossil fuel use for power and heating in farm buildings.

Looking ahead, if demand for biomass grows in Scotand, UK and elsewhere as countries expand BECCS capacity the market prices for PECs may change. Input costs can also vary significantly. It is beyond scope of this research to deliver a full analysis of future scenarios for the market, or local market dynamics related to specific BECCS sites, but it is clear from the range of profitability demonstrated in Section 5.1, that a range of scenarios should be planned for.

Interactions between PECs and adjacent land-use and wider landscapes and ecology was shown to be an important location factor to consider. Impacts could be beneficial, such as shading / shelter for livestock and to reduce wind exposure for adjacent crops, or could be negative depending on local landscape features, for example reduced yields in adjacent crops due to shading. Positive potential biodiversity impacts have been suggested by some stakeholders, such as habitat for birds, mammals and beneficial insects if edges between PEC and other land-use is maximised, but there was also concern about negative consequences of land-use change and monoculture PECs on biodiversity. Water management benefits also vary across the crops, and the lifecycle of the crops. The implication of the research is that the effective integration of PECs into natural landscapes and farming systems in Scotland to deliver maximum additional environmental benefits will require careful design in relation to the specific local environmental context.

A key issue for economic viability of PECs is the distribution of costs and income over time. Poor cashflow for farmers and land-managers is typical for PECs, because initial costs of establishment are not recouped until harvest after several years. The time from establishment to first harvest varies so the time where a farmer/ land-manager would likely experience cash flow challenges would also vary. The shortest time to first harvest was for Miscanthus, at around 2-3 years for full harvest with potentially a small harvest in the first year, SRC is typically 3 years for first harvest, and 6 years to first full harvest, and for SRF there is typically around 15 years till first harvest. Sequential planting can help create a more regular income because a portion of the crop would be ready for harvest each year. For SRC/ SRF this can be feasible if the harvesting equipment is already available on the farm, or the yearly harvest would be enough to warrant a visit from a contractor. For Miscanthus, there is an annual harvest once established so sequential planting of a portion of land intended for Miscanthus each year would allow for some of initial income to be used for subsequent planting reducing the size of initial outlay whilst increasing the area allocated to the crop over time.

Income diversification

Stakeholder comments suggest that the current levels of interest from farmers in diversification, including into crops with lower input costs and stable income, could be a significant enabler to the uptake of PECs. However, the economic analysis suggests that this would only be the case, if the core barriers around profitability, cashflow and financial risk were addressed.

Other factors influencing PEC uptake

The research found that farmer and land manager attitudes, habits, skills and perceptions, as well as those of the wider community are likely to be influential, alongside the economics, in determining the degree to which energy crops are adopted in Scotland. Low appetite for financial risk is a key preventative factor, with most farmers looking to reduce their exposure to risk and so only likely to be interested in energy crops if they are perceived as a low risk strategy in their own right, or a beneficial diversification of income as part of a wider business risk reduction strategy. The research suggests that, without clearer evidence of favourable market, price and productivity the current perception of these crops as relatively risky is unlikely to change. Concerns about competition with other crops, sustainability credentials, and public perception of the ‘morality’ of energy crops is also likely to influence farmers and land-manager attitudes. Alongside these factors, it was highlighted during the research that farmers often have a strong preference for their current farming enterprises and so may be reluctant to adopt new crops even if they appear financially advantageous and that a significantly higher financial return may be needed to persuade a shift to energy crops in these circumstances.

State of the evidence base and identification of any key gaps

The key gaps and debates in the literature were described in Section 4, and limitations in economic analysis in Section 5. The research shows a need for more robust evidence on potential yields, production costs and environmental impacts specifically for Scotland.

Quantification of potential wider farm benefits, such as shelter for livestock, and estimation of economic value of these benefits to farmers was not identified through this research, but could help create a fuller picture of the economic potential of energy crops for Scotland.

We found limited research on the risks for crop failure / poor productivity from pest, diseases, extreme weather which hampers full assessment of the financial risk exposure of farmers and land-managers associated with planting PECs.

This study has not included a detailed comparison of PECs for NETs with annual bioenergy crops and other bioenergy technologies, such as anaerobic digestion or smaller scale use of PECs on farms for direct energy generation. The REA and stakeholder feedback indicated potential for farmers to benefit from energy security and reduce energy costs if they were to utilise energy crops for their own energy generation. This study has not modelled the current economics of investment in relevant plant and ongoing cost: benefit of this scenario. This research would be potentially beneficial to understand how local small-scale use compares to larger scale use in NETs, and therefore fully understand the relative economic potential of PECs in Scotland.

The research found debates and discussions about how land should be used to fulfil societies various material needs (food, fuel, fibre etc.) and provide space for biodiversity and deliver other ecosystem services. To inform this debate various additional factors, beyond the scope of this research are relevant including the relative benefits of using land for PECs vs other types of renewable energy such as wind and solar energy. Stakeholders highlighted that solar, for example compares, well and there is growing interest in agrivoltaics – solar voltaic panels within agricultural land that may still retain some of its agricultural use such as livestock grazing.

 

Conclusions

Perennial energy crops have the potential to generate income for farmers and land-managers in Scotland.

  • However, income is likely to be lower than they could earn from other farm enterprises, such as lowland cattle and sheep and ‘mixed agriculture’, that are typical on the types of land which may be suitable.
  • The exception is where PEC profitability is compared to ‘general cropping: forage’ farming type (growing crops for animal consumption, usually on lower quality land) this activity typically makes a significant loss, so PECs compared very favourably in the analysis.
  • for PECs to be viewed as an attractive, economically viable option by farmers and land managers there is a need for greater confidence that it will deliver good economic returns. The high upfront establishment costs for perennial energy crops and low revenue potential are both likely to hinder uptake.

Profitability of perennial energy crops based on gross margin calculations

If costs and income were spread equally over the lifetime of the crop and compared, PECs are less profitable than current farming enterprises, except for ‘general cropping: forage’ which is not typically making a profit.

  • Of the three crops studied, Miscanthus showed the highest average gross margin at £382 per hectare per year but there are some potentially limiting factors:
    • uncertainty about achievable yields in the Scottish climate and on the grades of land above category 4.1 in the Land Capability for Agriculture in Scotland. If yields were lower, then profit may be lower.
    • Limited theoretical growing area in Scotland – much lower than for SRF or SRC based on analysis of land quality and characteristics and Scotland’s climate.
  • SRF and SRC showed lower profitability for farmers: £80 and £87 per hectare per year over their lifetime respectively for SRF: broadleaved and SRC, making them less attractive but there is more suitable land for growing these. SRF conifer would see a negative gross margin i.e., the production costs outweigh the value of the crop sold.

Potential opportunities

  • The research also identified some potential positive attributes of PECs which might encourage uptake – PECs could help diversify a business, creating additional income, without adding significant additional labour requirements or ongoing input costs – minimal management time and inputs are required once crops are established.

Potential barriers

  • Cash flow could pose a problem – the distribution of costs and income year-on-year for PECs is significantly different to typical farming activities which have an annual profit cycle. PECs need investment in site preparation and planting upfront, but income only arrives after first harvest several years later (2-3 years Miscanthus, 6 for SRC, 15 for SRF) and then only periodically after that.
  • Coupled with uncertainty about market demand and achievable crop sale prices, the need for upfront investment to establish PEC production, means farmers and land managers may view them as a risky proposition and be reluctant to grow them.
  • We identified other potential barriers to uptake, including farmer and land-manager unfamiliarity with PEC production, low appetite for risk, need for new skills, access to equipment and services, and concerns about community perception of land-use change and impacts on other agricultural production, e.g. available animal feed.

Enhancing economic potential and production of PECs

Potential approaches to improve economic potential in Scotland include:

  • financial incentives, such as government specific subsidies under future agricultural support,
  • risk reduction strategies such as secure, attractively-priced contracts with end markets, alongside expansion of the market.
  • Innovations to allow processing at the farm and to improve transportability of crops could also help to increase the economically viable travel distance.

Implications for wider Scottish economy:

  • Previous research suggests 38000 could be feasibly planted by 2032 (scenario one) and 90,000 by 2045 (scenario two).
  • We found that, if land to match this level of demand, was utilised for perennial energy crops (using the scenarios as defined in section 5.2), it would create a gain in gross margin of around £9.6 million (scenario 1) or a loss of around £9.5 million (scenario two) across the regions.

Economically viable production locations:

Economically viable production locations for PECs are influenced by multiple factors including proximity to markets (current biomass energy plants and potential future BECCS plants) and local enough access to services and facilities for crop management (e.g. harvesting contractors) to avoid excessive costs.

  • We identified suitable growing regions (some SRC/Miscanthus and most for SRF) within an economically viable transport distance to existing biomass plants and potential sites for BECCS near the proposed east coast carbon capture and storage feeder pipeline (assumed 50-100 km).
  • As SRF is economically uncompetitive against current land-use, this suggests economic viability may be a barrier to PEC production increases even if suitable land is available.

Potential further steps

Key debates and areas for further research include:

  • Considering more in-depth ‘whole farm’ economic analysis.  This study focused on gross margin comparison, which is useful for comparing specific crops and farm enterprises, but has limitations in terms of how well it allows assessment of integration of energy crops into a whole farm business. This will vary farm to farm but could be explored through farm case studies. This could include considering a wider range of costs for farmers and that after initial set up the PECs would require less workload.
  • Comparing, the economic and environmental potential of using land for energy crops with utilising the same land for other renewable energy options (for example using the land for solar panels alongside grazing) and
  • Potential role for on-farm use of perennial energy crops.
  • Considering future biomass markets, including how future Greenhouse Gas Removal (GGR) schemes, global demand and demand from biotechnology sector may impact it.
  • Identifying how to make domestic biomass from energy crops a more attractive option than imports and a more profitable use of land, and on what basis this can be justified. For example, taking account of full LCA and rewarding greatest emission saving.
  • Considering in more detail the role of PECs in the context of how the agriculture sector is changing and how it may have to change to reduce GHG emissions.
  • Considering the value, including the financial value, of other benefits of energy crops, such as flood mitigation or animal shelter, relative to existing or potential alternative land-uses.
  • Exploring how PECs support/interact with tier 2 or 3 objectives of the ARP.
  • Considering the impact of subsidies.

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Appendix A: Policy Context for Energy Crops in Scotland

Climate Change Policy

The Update to the Climate Change Plan (CCPu)[27], published by the Scottish Government in December 2020, whilst focused on reducing emissions, identifies the need to also remove carbon dioxide from the atmosphere to compensate for residual emissions. It foresees a role for technologies to achieve a net reduction in emissions – often referred to as Negative Emissions technologies (NETs). It identifies several NETs pathways with potential in Scotland, including bioenergy with carbon capture and storage (BECCS). Climate Committee’s (CCC) 6th Carbon Budget sets out that achieving the required scale of BECCS will necessitate a significant increase in the domestic production of biomass feedstocks[28].

The CCC’s 2022 review of Scotland’s progress[29] highlighted that Scotland’s planned deployment of NETs was ambitious, comprising two thirds of UK government overall ambition for 2030, but also notes the advantage of Scotland’s large land area and potential to draw on substantial biomass stocks. It recommends consideration of the impacts and interactions that increased domestic biomass production could have on land use and agriculture. The Scottish Government has acknowledged that these targets can’t be met – the NETs feasibility study gives more realistic targets[30]. Failure to meet NETs targets for Scotland implies deeper emissions reductions in harder-to-decarbonise sectors, such as aviation and agriculture, and so it is critical to consider how farmers and land-managers can deliver the necessary biomass feedstocks. The CCPu includes a proposal to develop rural support policy to enable, encourage planting of biomass crops within broader measures on sustainable, low carbon farming[31]. The CCC recommends maintenance and enhancement of support for agroforestry[32], and a target of 5% trees on farmland by 2035.

Agricultural policy

Scottish Government’s Vision for Agriculture recognises the essential role agriculture has in delivering sustainable food production, climate adaptation and mitigation, biodiversity recovery and nature restoration and proposes that future subsidy support for agriculture will be split across unconditional support and support targeted to environmental outcomes, including low carbon farming and biodiversity The new Scottish Agriculture Bill as introduced to parliament on 28th September 2023 provides a replacement for the Common Agricultural Policy (CAP) and has been drafted to provide the required powers and framework to deliver the Vision for Agriculture. The bill would require Scottish Ministers to prepare a five-year Rural Support Plan for farming, forestry, and rural development. The Agricultural Reform Route Map (ruralpayments.org) sets out the milestones and timescales for change. The Agriculture Bill and Rural Support Plan will have implications for how economically viable it may be in future for farmers and land-managers to grow energy crops. Whilst the details are yet to be confirmed, it is clear that any expansion of perennial energy crops will need to take these policy developments into account.

Other key policies:

Principles of ‘just transition’ are defined in legislation[33] and Scotland’s draft ‘Energy Strategy and Just Transition Plan’[34] was published in January 2023. It describes Scotland’s aim to use bioenergy where it can best support Scotland’s Net Zero Journey, and aligns with and supports Scotland’s goals for protecting and restoring nature. It contains a commitment to review the potential to scale up domestic biomass supply chains. Bioenergy crops, if economically viable, could offer the agricultural sector a new income stream and support the rural economy, which would be consistent with the draft plan. The draft plan also includes a proposal to develop a strategic framework for the most appropriate use of finite bio-resources (published in a Bioenergy Action Plan), acknowledging the potential for competing demands on land and natural resources. CCPu also acknowledges the need for open a discussion on optimum land uses beyond just farming and food production to multi-faceted land use including forestry, peatland restoration and management and biomass production.

UK biomass policy context

The UK Government’s Department for Energy Security and Net Zero (DESNZ) published a Biomass Strategy in August 2023 which set out the Government’s view that well-regulated BECCS can deliver negative emissions and ensure positive outcomes for people, the environment, and the climate. It commits the UK Government to strengthen sustainability criteria and verification processes for biomass, acknowledging challenges with international supply chains, and creating a cross-sector sustainability framework for biomass (subject to consultation). The focus will be on addressing greenhouse gas emissions, indirect land-use change, and potentially soil carbon changes. The strategy anticipates a key role for both domestic and imported biomass use across the economy, on a limited timescale. It also sets out how the government is actively developing demand side policies to support emerging technologies such as BECCS and Greenhouse Gas Reduction (GGR) business models, for example the potential for a ‘Contracts for Difference’ (CfD)[35] approach. The strategy acknowledges that bioenergy policy involves a mix of reserved and non-reserved powers, and so as the Scottish Government develops its draft Bioenergy Policy Statement, Scotland has an opportunity to build on UK policies and develop policies appropriate for Scotland.

Appendix B: Introduction to Perennial Energy Crops

Introduction to Miscanthus

Miscanthus is a tall perennial grass with woody canes like bamboo, of East Asian Origin. The most common variety of Miscanthus grown is the sterile hybrid Miscanthus x giganteus (M. giganteus). Miscanthus is a renewable source of fibre which has a wide potential range of uses as biomass or fibre. Whilst Miscanthus can be grown in parts of Scotland, it is not currently grown at commercial scale and further trials are required to verify its potential future contribution (Meek et al., 2022). Nonetheless, Martin, et al 2020 found 51,800ha of land is theoretically suitable in Scotland to grow Miscanthus which could produce 2.59TWh/yr and 0.52Modt/yr.

To grow, the crop must be established by planting pieces of rhizome (underground plant stem capable of producing the shoot and root systems) which have been collected from fields where Miscanthus is already established[36]. Prior to planting, site preparation may typically involve breaking up compacted soil, removing weeds (using herbicides), ploughing to 30cm depth, then further levelling and soil cultivation to create a fine level soil to around 15cm[37]. Equipment which is typically available on an arable farm can be used for this site preparation and planting. Planting using specialist equipment achieves best results, but a potato planter could alternatively be used[38]. Biodegradable plastic film to prevent frost damage and retain moisture and fencing to prevent rabbits damage can improve success of crop establishment. Once planted, some gap filling might be needed (done manually) and chemical weed control in the first year or so. Fertilisers are not usually needed. After the first year the material is cut back and left in the field. In year 2, depending on the growth rate, there will be a small harvest, or another cut back. Once established a Miscanthus crop is harvested annually, usually in early spring when moisture content is lower, and can be productive for around 15 years. The material is baled, or sometime chipped, to enable easier transport and storage. Sometimes drying is required in storage (natural or mechanical ventilation). At the end of the crop lifetime, to revert the land to other uses, a herbicide is often used to kill Miscanthus shoots and rhizome, followed by ploughing.

Introduction to short rotation coppice[39]

Short Rotation Coppice (SRC) commonly consists of high-yielding varieties of either poplar or willow, densely planted on a piece of land. The solid, woody biomass provides a source of biofuel that is either used alone or combined with other fuels to power district heating systems and electric power generation stations[40],[41]. It was noted previously by Martin et al. (2020), that the production of energy crops in Scotland has in the past been limited, with only SRC currently grown at small commercial scale (250ha). There is greater potential for further SRC cultivation in Scotland provided that suitable land area is available.

Most types of land, except for heavy clay soils and water-logged land, are suitable for SRC. The initial steps to establishment include removing weeds using herbicide, ploughing to 30cm and further cultivation to 15cm. Rods or cuttings are planted with a specialist planter. Gap filling and protection using rabbit or deer fencing may also be needed. During the first year weed control using herbicides and control of plant diseases using pesticides may be needed. Once established, SRC plantations are typically harvested at 3-year intervals using a forage harvester with a specific cutting system, then chipped and stored outside on a concrete base or in the field. Plantations typically remain productive for 15-25 years[42]. After this, a new planting can be established, or the field reverted through a process that involves stump grinding and the application of herbicides to prevent regrowth.

Introduction to short rotation forestry

Short rotation forestry (SRF) involves planting relatively fast-growing tree species and harvesting them for biomass after around 15-20 years, which is much quicker than conventional forestry. Species can be coniferous (e.g., Sitka spruce, Douglas fir) or broadleaved (e.g., aspen, poplar, silver birch, downy birch, sycamore). SRF is not currently operated commercially in Scotland although there are some trial plots. Nonetheless 912,600 ha of suitable land is theoretically currently suitable for planting of SRF in Scotland (Martin et al., 2020). Limited, recent literature material and evidence was found in the REA relating to the economic potential of SRF in and around the UK.

Process steps are like conventional forestry: the plantation is grown from seedlings or cuttings, or sometimes direct seeding, into land prepared through steps such as drainage, ploughing, and fencing. Some weed control or replacement planting may be needed initially, but after this limited maintenance is required. All the trees in a growing area are harvested at the same time using specialist cutting equipment, then either cut into lengths and stacked to air dry ready for collection or chipped on site. With SRC the shorter rotation, and the higher planting density, reduces the potential for co-production of logs for sawmill timber[43]. After harvest the site can be cleared, using machinery and herbicides as per SRC and then replanted or reverted to other land-use. Alternatively new stems can be allowed to regrow for coppicing, or a single good stem selected to continue growing for harvest after 15-20 years. Broadleaved varieties tend to produce higher wood density which is advantageous for use as bioenergy.

Appendix C: Methodology to Rapid Evidence Review

  • The Rapid Evidence Assessment (REA) methodology used for this project aligns with NERC methodology[44] and comprised of the following steps.
  • Define the search strategy protocol, identify key search words or terms, define inclusion/exclusion criteria. A list of key words, terms and search strings was created and reviewed by Ricardo’s bioenergy and agriculture technical experts and the project steering group to direct the REA review to the most relevant sources. This list was and divided into six relevant categories ‘Energy Crops’; ‘Economic potential’; ‘Farm business and agronomic considerations’; ‘Preferred/feasible locations’; ‘Agricultural & land-use options’; ‘Other considerations e.g., just transition, decarbonisation’ to ensure that all appropriate aspects of the economic potential of energy crops were identified which supported the focus the review. Any literature that is considered out of scope based on our list of assumptions was excluded from the search. We also excluded literature that is older than 10 years, unless it was from a credible source and was the only piece of evidence available (particularly for data).
  • Searching for evidence and recording findings. Literature was searched using Google Scholar and Science Direct, utilising our accounts with Science Direct and Research Gate to access restricted pdfs where required. Grey literature, such as farming press and industry reports were used to provide examples and case studies of the economic potential of energy crops. In addition to the search engines, two existing evidence reviews, prepared by Ricardo were used to sources relevant literature: ‘Evidence review: Perennial energy crops and their potential in Scotland’ and ‘Evidence review: Increasing Sustainable Bioenergy Feedstocks Feasibility Study’. Academic paper ‘Greenhouse Gas Removal Technologies –approaches and implementation pathways in Scotland’ (Haszeldine et al, 2019) was also provided to us to supplement our evidence base. For each individual search a unique search reference was assigned, the date, search string used, total number of results found, and the total number of relevant papers found were recorded. Our search strings can be found in the table below.

TableA‑2: Search strings used for REA

“Perennial energy crops” “Scotland”

economic potential bioenergy crops Scotland

“Perennial energy crops” “farm level” “Scotland”

“Short rotation coppice” “economic potential” “Scotland”

Miscanthus energy crop Scotland

“Miscanthus” “economic potential” “UK”

economic potential “short rotation forestry” Scotland

economic impact short rotation coppice Scotland

profitability short rotation coppice UK

profitability short rotation forestry UK

farmers weekly economic potential of perennial energy crops

“short rotation forestry” “UK” “profit”

revenue + perennial energy crops Scotland

Short Rotation Forestry Trials in Scotland Forest Research

short rotation forestry for energy “willow” “poplar” “economics”

perennial energy crops “operating costs” “UK”

hemp energy crop economics Scotland

All results were recorded in an excel spreadsheet with information extracted on the following:

  • Country
  • Type of energy crop (SRC, SFC or Miscanthus)
  • Additional information on crop type
  • Scale of deployment
  • Positive economic potential
  • Negative economic potential
  • Issues/barriers of deployment (non-economic uptake considerations)
  • Temporal considerations (e.g., agronomic/climatic conditions)
  • Further economic potential (e.g., decarbonisation of agricultural practices and creation of new jobs)

A RAG (red, amber, green) rating was assigned to each source, based on the g criteria:

Description

Rating

Quality

Peer reviewed journal, sound data sources and methodology

Green

Government funded research reports, sound data sources and methodology

Green

Research funded by NGOs (e.g., AHDB), sound data sources and methodology

Amber

Work is unreliable because of unreliable data sources, or limited sources, or because the method is not robust

Red

Information from websites, blogs etc., of unknown quality

Red

Relevance

Timeframe: within last 10 years

Green

Timeframe: within last 20 years

Amber

Timeframe: older than 20 years

Red

  • Screening. Sources of evidence was then screened initially by title and then accepted papers were then screened again using the summary or abstract. Literature was screened for information on the following inclusion criteria:
  • SRC, SRF, Miscanthus (and hemp / alternatives if strong evidence to show economic viability)
  • Economic potential (positive and negative) of energy crops – qualitative and quantitative information
  • How farmers / land-managers are making decisions about which enterprises and land-uses to adopt and research which provides evidence of likely preferences and decision-making influences.
  • Agronomic or other considerations which would influence viability / adoption by farmers / land-managers.
  • Extract and appraise the evidence. The screening provided an organised list of papers which enabled evidence to be extracted directly from the literature into the report. Literature extracted also guided the internal workshop and supported information included in the SWOT and PESTLE tables.

Appendix D Evidence of positive economic potential

We found some evidence in literature that PECs can be profitable for farmers and land managers, but limited studies directly applicable to Scotland and to the current economic climate. The price of fuels and other agricultural inputs have been subject to significant rises and fluctuations since most studies were undertaken and studies were mostly in locations with different growing conditions to Scotland. Economic performance of biomass production is influenced by production costs, crop yields, crop price and end-use/market opportunities (Olba-Zięty et al., 2021).

Several studies comparing energy crops reported a high return per hectare for miscanthus, (Martin et al., 2020, Zhang et al, 2020). One reason for this is that miscanthus can produce high outputs from low inputs which is economically significant for farmers (Donnison and Fraser 2016), particularly in the current context of high agricultural input costs. Miscanthus is attractive as it requires few farm operations, has low labour needs, crop management is straightforward and existing farming machinery and skills can be utilised in its production (Shepherd et al., 2020a and Glithero et al 2013) thus improving its economic potential in comparison to annual crops (such as cereals) used for energy. Growers invest in miscanthus due to this low maintenance cost along with the low requirement for field operations (Shepherd et al., 2020). However, Mola-Yudego et al., (2014) in a Swedish study found SRC willow had the lowest production costs overall, compared with other energy crops (miscanthus, reed canary grass and triticale). The production costs, and therefore profit, will vary depending on equipment available on farm (Ostwald et al,2013a).

The tree species chosen for SRF influences plantation establishment costs and therefore enterprise profitability – costs vary between species: Hybrid Aspen requires a costly micro-propagation technique, and so is more costly to establish than Poplar (Tullus et al., 2013). The literature did not provide detailed information on how well-suited different species are to the Scottish climate and the expected yields of biomass in Scotland. Initial indications from trials currently underway in Scotland (Parratt, M, 2017) suggest Hybrid Apsen appears to have most potential, with common alder, silver birch and Sitka spruce having potential at some sites, but full assessment of biomass is not complete and economics are not assessed.

A farming press example of a grower for Terravesta, the major purchaser of Miscanthus in England (Davies, in Farmers Weekly, 2020), reported that for Miscanthus, an average net profit of £530.85/ha over a 15-year period based on a mature yield of 14/t/ha was achievable. Stakeholders interviewed for this study indicated that Miscanthus is still economically viable under this growing model in England, despite current economic conditions, but questioned whether this yield, which would be a key determinant of profit, is feasible in Scottish growing conditions.

Evidence for negative economic impacts

The most prominent evidence of negative economic impacts in the literature was the high upfront cost to establish PECs, lack of established markets, and the uncertainty over the stability of the long-term market (Martin et al., 2020 and Witzel and Finger 2016). Profitability and economic considerations for farmers are dominated by these costs, market dynamics and biomass yield (Zimmermann et al., 2014).

High establishment costs and uncertainties about the market, mean that farmers may perceive PECs as financially risky and are discouraged from growing them (Witzel and Finger 2016, Zimmermann et al., 2014, Hastings et al., 2017). Previous farm-scale modelling was conducted to improve the understanding of the potential economic PEC supply across the UK. The results concluded that without increases in market prices, SRC willow would likely only provide a small proportion of the UK’s PEC target (Alexander et al., 2014). Similar studies were not found for SRF and Miscanthus, and the economics will have changed since this study making it difficult to understand from the literature if this is still the case but it is clear market access and price is a key issue.

In relation to Scotland specifically, the research found that high initial capital investment and a delayed period of revenue are major factors that negatively influence economic potential of PECs. Farmers receive no income from crop sales in the first years after establishment of PECs leading to poor cash flow, which can be an obstacle preventing farmer uptake (Bocquého, 2017). This period before first crop sales varies: typically 2-3 years for miscanthus production (Martin et al. (2020), around 4 years for SRC (Warren, 2016), and 10-20 years for SRF (Martin et al., 2020, Tullus et al., 2013), meaning a farmer may be waiting several years before the crop breaks even, for example miscanthus typically breaks even after between 4 and 11 years (Martin et al 2020).

Economic potential of PECs, in comparison to other crops

The literature review did not provide clear evidence of how the three key PECs being studied here compare economically to other crops, annual crops and agricultural land-uses – some studies showed favourable comparison and others did not. Key studies are highlighted below, but limited insights can be gained on this question from the literature given the recent economic changes affecting agricultural costs and market prices. See Section 5 for a comparative analysis reflecting current economic situation. Petrenko and Searle (2016) found the profitability of miscanthus and SRC to be competitive, with oats in the south of England, and with oats and rye in Southern Germany and, but could not compete with wheat in Europe generally or typical arable rotations in France (Glithero et al., 2013). Lower input costs may mean that PECs are more competitive now, than arable crops which typically require high levels of expensive inputs (such as fuel, pesticides and fertiliser), but literature does not confirm this. Glithero et al (2013) showed miscanthus to have lower biomass production costs (calculated as cost per gigajoule of energy) in comparison to straw-based crops in England. Busch (2017), in Germany, found SRC to be financially superior when compared to three different crop rotation systems consisting of oilseed rape, wheat, barley, and maize crops, concluding that SRC can compete against annual crops provided proper site selection and a suitable market (in this case, wood chip production). Mola-Yudego et al., (2014) highlight research in Northern Ireland which showed similar gross margin to grain production, assuming average yields in both cases.

We did not find research which compared energy crop economics with livestock farming systems economics.

Influences on farmer and land-manager decisions on planting PECs

One of the main factors affecting the uptake of PEC is economic profitability (Olba-Zięty,2021). Appetite for and perception of financial risk, skills, attitudes and access to markets can also influence farmer and land-manager decisions about planting PECs. Evidence from the literature, and our research interviews with stakeholders suggests that even where PECs, or energy crops in general, can deliver positive economic results for farmers and land managers, this on its own is not always sufficient to convince them to start growing PECs. A choice-experiment study in Sweden, found that lower production costs can enable farmers to achieve higher profit from energy crops, in comparison the traditional crops, but that further compensation of up to 215 Euro per hectare would be needed to persuade a farmer to switch to SRC (Ostwald et al,2013a).

A study by Warren (2014) on farmers’ attitudes to PECs in south-west Scotland found that farmers perceived growing SRC to be ‘financially risky’. SRC production was associated with uncertain returns on harvested wood as prices can be volatile. A lack of access to local markets was also highlighted as a potential barrier to current market adoption by producers (Alexander et al., 2014).

Other economic features of PEC production which influence economic potential for farmers and land-managers in Scotland

Producing PECs has specific economic implications for growers which influence their economic potential and attractiveness. These include challenges: lack of flexibility of land-use, reduced market responsiveness; and opportunities for diversification alongside current farming enterprises.

Unlike with annual arable crops, miscanthus producers can’t maximise profitability by changing crop each year to react to market prices (Hastings et al. (2017). The implication of this, which was highlighted during stakeholder interviews, is that to view PECs as economically worthwhile, farmers need confidence that they can achieve an acceptable and secure market price into the future. Long term production contracts between private biomass processors/plants and farmers are an important consideration in managing financial risk for producers (Bocquého, 2017). Stakeholders highlighted that joined up contracts including harvesting and haulage services, currently being used for some crops, can also help reduce risk and simplify the economics for producers.

The literature review suggested that the way PECs are deployed on farms influences their economic potential. Integration of PECs alongside other enterprises and on land which is not performing well could be advantageous. Glithero et al., (2013) reported that when integrated as a diversification enterprise on-farm miscanthus can be highly competitive. Less productive land, for example poor agricultural land with insufficient returns for food crop, is suitable for miscanthus (Shepherd et al., 2020a), which implies it could provide an economic benefit if deployed on this type of land within a farm.

Brown et al., (2016) report that introducing SRC into traditional cropping systems allows producers to diversify their farming operation, which in turn enhances income, improves income security and reduces risk. Alexander and Moran., 2013, similarly found a portfolio of crops including conventional crops, alongside Miscanthus has been found to achieve a more stable income for farmers, and furthermore conclude that, as farms typically operate in a risk-averse manner, reduced risk is an important factor in farmer decision-making for PECs.

The economic potential of SRC is largely dependent on the establishment of strong markets and demand driven by power companies (Brown, 2016). In the UK, it is generally found that further development of energy cropping only occurs once a plant has been built and several farmers adopt SRC practices to supply crops for that plant (Alexander et al., 2015).

Opportunities to improve economic potential of PECs in Scotland

Cultivation techniques, crop variety choice and other technological developments can influence economic potential of PECs in Scotland and have potential to improve profitability for farmers and land managers in future. For example, the use of plastic mulch film to reduce establishment time can improve crop economics (Hastings et al. 2017). Introduction of new and seed propagated hybrids of Miscanthus alongside agronomic developments have been projected to significantly reduce the cost of Miscanthus production. Mobile briquetting of Miscanthus can also increase the economic potential of Miscanthus (Perrin et al., 2017). Through the Biomass Innovation Fund, £32 million of research funding was awarded to innovation projects across the UK to deliver ‘commercially viable innovations in biomass production. Several innovations have potential to improve yields and reduce production costs for Miscanthus in Scotland, including efficient and mobile harvesting equipment and development of new cultivars more suited to colder climates (see Appendix F).

The literature review and stakeholder interviews both highlighted some factors which can negatively affect the economics of PEC production, which if addressed are potential opportunities to improve economic performance. Gaps in the crop (patchiness) was a key factor reducing profitability of miscanthus in the UK, resulting in longer payback periods. Tackling this by addressing issues such as planting technique, bad rhizome quality, poor overwintering, or variations in the soil quality helps maximise crop yield and improve farmer income (Zimmermann et al., 2014). Ensuring access for harvesting equipment is essential for economics of SRF to be viable – ensuring areas planted are on slopes not more than around 20 degrees is important to ensure the economic benefits of mechanised harvesting can be accessed (Martin et al 2020). For SRF effective plantation establishment is important for the economics and general success of a SRF plantation, yet our research did not find clear consensus on how to achieve this: Tullus et al., 2013 found low planting density was preferred amongst producers to minimize establishment costs, although impact on yield is uncertain in the literature. Research also found that single species monocultures can offer greatest economic return by providing higher yields per hectare (Liu et al., 2018), highest yield are achieved on fertile soil (Tullus et al., 2013) or under intensive management systems, including weed control, fertilizer application and irrigation (Walle et al., 2007).

Evidence of potential for Scotland’s wider economy

There was limited research addressing the potential contribution to the wider Scottish economy and a just transition, but some opportunities and challenges can be inferred. These include sales for local energy generation and other industrial uses, employment opportunities in contract services, along with potential payments for environmental outcomes. The requirement for contractors and local services during annual Miscanthus harvesting presents employment opportunities (Martin et al., 2020), as does SRF planting and harvesting (Liu et al., 2018). Depending on the existing farm enterprises, and choice of PEC, the workload for PECs may fall at a different time of year to other peaks in labour demand, helping to spread labour requirement through the year and reduce overall labour requirement. This could make farming more economically viable on farms which rely on family labour or very small workforces and reduce seasonal labour demands.

In addition to being used as BECCS feedstock, PECs have other potential uses and markets. Miscanthus can be sold for animal bedding, thatching, paper production, horticulture, construction materials[45], and biodegradable plastics (Anejionu and Woods 2019). There has been research on using Miscanthus as a feedstock for fermentation to transport fuels or through anaerobic digestion (AD) to biogas (Witzel and Finger, 2016). Miscanthus for AD has been found to be uneconomical according to Whittaker et al.(2016). Our stakeholder interviews confirmed that farmers would benefit more from growing feedstocks tailored to AD if this is their desired market, yet Winkler et al. (2020) reported significant potential for additional income from biogas production.

SRF and SRC, (when processed into woodchips) can provide a fuel source for biomass boilers and CHP units on-farm and for local domestic or other use[46] (Spackman, 2012, Ranacher et al., 2021). This can be an alternative market to diversify income sources and also potentially save farmers money on their own energy bills. The literature did not provide details on the economic implications of this but the stakeholder interviews flagged that farmers are currently interested in exploring opportunities to cut energy bills. Miscanthus was also identified to be used in small scale CHP plants on-farms for heating buildings and for domestic uses such as wood burners[47].

Beyond selling the biomass from PECs as a product, the literature reviewed suggested the potential of PECs to deliver environmental and ecological benefits which could potentially be monetised. SRC and SRF are currently not eligible for carbon credits, and it is unlikely that PECs can provide evidenced carbon storage in biomass or soils in order to qualify under other certification schemes. There may be opportunities to gain economic benefit from flood protection and biodiversity benefits that some PECs can deliver – the research has not identified significant information on this.

Evidence of non-economic opportunities

Non-economic opportunities and benefits of PECs were identified during the research, including several relating to positive environmental outcomes such as reduced agro-chemical use and biodiversity. All three PECs investigated require less chemical inputs, and reduce soil and water pollution (McCalmont et al., 2017). They also sequester carbon, for example miscanthus has a carbon mitigation potential of 4.0–5.3 Mg C ha-1 yr-1 (Zimmermann et al., 2014). Conversion of agricultural land to SRC leads to a reduction in management intensity of the land, resulting in potential soil benefits (Schiberna et al., 2021). The impacts of SRF may be positive or negative depending on what the land was previously used for. Soil compaction and disturbance caused by the harvest of SRF can lead to erosion and a loss in soil organic matter (Martin et al., 2020). Impacts may be neutral or possibly negative if conversion of land is from pasture or native forest to SRF (Griffiths et al., 2019). However, if displacing arable production, SRF has been reported to improve soil stability (Martin et al., 2020) with the potential to have positive effects on carbon soil organic carbon, water retention and erosion rates (Griffiths et al., 2019). SRF can also help flood alleviation as a SRF plantation would slow the rate of water flow (Martin et al., 2020).

The opportunities for biodiversity improvements resulting from PECs vary depending on planting, prior land-use and landscape context. Miscanthus has been reported to have positive effects on biodiversity (Bourke et al 2014 and Berkley et al 2018) in comparison to arable cropping systems. Shepherd et al., 2020 found an abundance of wildlife in UK miscanthus fields which, apart from at harvest time is left undisturbed. However, the effects on biodiversity of large-scale plantations are unknown (Bourke et al 2014). The introduction of SRC sites within arable cropping systems has in some cases been found to enhance the presence of some pollinators (hoverflies, bumblebees and butterflies), which can benefit crop production. However, it should be noted that these benefits are highly context dependent (Berkley et al., 2018). Opportunities to increase bird populations and diversity is thought to increase if native species of SRF are introduced (Martin et al., 2020).

Challenges and deployment barriers

The research identified several non-economic challenges facing the production of PECs in Scotland, relating to skills, land-use commitment, compatibility with current culture and habits, farm businesses, perceived land suitability and environmental concerns. Deployment barriers for Miscanthus include the need for farmers to commit land for a long period of time, land quality, knowledge (Glithero et al 2013), profitability, time to financial return and social resistance relating to whether land should be used for energy or food production (Anejionu and Woods 2019). These barriers also apply largely to SRC and SRF: land committed towards SRC and SRF will be in production for several years and conversion back to arable and the removal of tree roots is challenging (Warren 2016). Additionally for SRF land conversion may be deemed irreversible as reversion to farming use may be prohibited by government regulations once SRF is planted, and the land will no longer be classed as agricultural.

Lack of access to specialist skills (including a shortage of trained foresters[48]) and to specialist contractors and machinery (e.g., for SRF mechanised planting machines was also identified as a barrier to deployment. The most likely cause of this is limited demand and a ‘lack of off the shelf machinery’[49]. Whilst this could be seen as an opportunity for development of new infrastructure and employment opportunities, it could currently also be seen as a practical constraint for many producers. The establishment of SRC requires new skills and different machinery compared to conventional cropping, this unfamiliarity and technical lack of knowledge prohibits adoption by producers (Warren, 2014). Stakeholders who we interviewed suggested that there is increased interest amongst farmers in diversification, but that appetite for change was tempered by concern about moving into unfamiliar activities which require new skills.

Culture and attitudes can be a barrier to PEC deployment. Warren et al. (2016) found Scottish farmers opposed SRC (willow) production because they considered it was not suitable for their current farming business or the land. Whilst fertile land is best for SRF production, a study conducted by Walle et al., 2007 found that farmers willing to introduce SRF, are not willing to do so on their ‘best agricultural soils’. Ranacher et al., 2021 found there is a gap in the available literature regarding farmers’ willingness to adopt short rotation plantations on less productive land. Another potential barrier which may prejudice farmers against SRC cultivation is the cultural separation of forestry and farming in Scotland – SRC has historically been viewed as a threat towards the socio-cultural identity of Scottish agriculture (Warren, 2014). In addition, an Environmental Impact Assessment – something which farmers may not be familiar with and is likely to incur costs – may be required[50] if converting agricultural land to forestry for SRF or SRC (Martin et al., 2020).

Concerns about biodiversity identified included, concern about SRF reducing the habitat for ground feeding birds and other ‘open land’ wildlife (Martin et al., 2020).The winterhardiness of miscanthus is considered a constraint for this crop in Scotland (Martin et al., 2020), and according to stakeholder may reduce achievable yields.

From a biofuel perspective, as with all PECs, it has been noted in the literature that energy generation from biomass is a potential source of direct and indirect emissions, despite carbon being captured during crop growth. Production, transport and processing are potential sources of direct emissions (Alexander et al., 2015). Considerations to limit such emissions, for example distance from farm to biomass plant, must therefore be taken into account. Indirect emissions related to land use change are more varied in the literature.It has been noted that the establishment of SRC on peat/high organic soils, found in the upland areas of Scotland, can potentially harm soil organic carbon (SOC) levels (Martin, 2020) . Existing sustainability criteria for the use of biomass to produce heat or electricity require that PECs are not grown on land that was peatland in January 2008, or of high biodiversity value, and that any change in SOC from cultivation of PECs is taken into account when checking that the electricity or heat produced meets the relevant GHG saving criteria (see e.g. Ofgem, 2018 and Ofgem, 2021, Low Carbon Contracts Company, 2022).

Other relevant crops and planting regimes

Aside from Miscanthus, SRC and SRF there are other potential energy crops – both perennial and annual crops – which can be used for bioenergy and which are potentially suitable for Scotland. The literature reviewed above mostly considered planting of PECs as replacement for arable crops . There is also literature to suggest integrating PECs alongside existing land-use may be feasible and potentially relevant for Scotland. These alternative crops and planting regimes are considered here. Note that relatively limited research was carried outon these as the PECs above were the core focus of this study.

Hemp

Hemp was once widely grown in Scotland and suits both the climate and growing conditions in the main agronomic areas especially parts of the Borders, East Lothian, Fife, Angus, Moray and the Black Isle. Hemp has a significant potential in carbon sequestration and there is evidence to demonstrate its suitability as a feedstock for bioenergy production therefore, bringing a new ‘cash-crop’ to Scotland which would also offer new job opportunities[51]. Dogbe and Revoredo-Giha., (2022) found through a farmer’s survey, that farmers identify diversification benefits i.e. planting hemp ‘as a safety net’ as a reason for producing hemp in Scotland. Biomass Connect technical article (2023), considering the UK as a whole, found hemp to have greater versatility and profitability than other biomass crops like Miscanthus, willow and poplar and high biomass yield (12-15t/ha of air-dried biomass). They also reported it to be an above-average energy crop for some biochemical-based biofuel production (in comparison to other similar yielding bioenergy crops)[52]. Hemp can also be used in bio-based building materials such as Hempcrete and textiles [53].

Hemp has the potential to provide high yields or returns with little or no pesticides and insecticides (Dogbe and Revoredo-Giha., 2022). It fits well into crop rotations with food and feed crops and helps improve soil structure and soil-borne pests. Constraints on producing hemp in Scotland includes the current lack of market as there are no large processing facilities in or near Scotland, strict regulations on growing hemp including, the need to obtain a costly license, and some reports of low profitability according to Scottish growers[54].

PECs in agroforestry systems,

Agroforestry is the planting of trees on farmland, alongside cropland or pastureland, usually in strips, clusters or scattered individual trees, that can be grazed or cultivated in between. The REA did not find specific studies focused on Scotland to show how PECs could be grown in agroforestry systems, but provided the design of agroforestry systems can allow for economically efficient planting, management and harvesting (i.e. still allow for machinery access), it could provide an advantageous model. Kralik et al., 2022[55] conducted a study to address the economic efficiency of agroforestry systems using SRC in comparison to conventional 4-year arable rotation, in Czechia. The results of this paper showed that the agroforestry system generate similar income and profits as the conventional annual crops when cultivating on appropriate sites and practicing good farming principles.

In terms of the scale of production which could be delivered through agroforestry, for the UK in general, Morris and Day (2023) estimated that 20% of UK farmland could transition to agroforestry by 2060. Utilising the aforementioned land area and yield data, the study observed three UK scenarios for SRC Willow. One scenario found where 30% of the yield arising from SRC Willow was used for bioenergy purpose and this would equate to 1.2 million tonnes of domestic wood fuel and therefore contribute significantly towards bioenergy needs and net zero.

Appendix E Methodology for economic analysis

Farm scale economic analysis

Calculating the gross margins for bioenergy crops

Step 1: Calculating the costs for the activities for the different types of bioenergy crops

Miscanthus, willow short rotation coppice (SRC), and short rotation forestry are the energy crops for which there is information that lets us build a baseline model that takes into consideration the different costs involved in the production process of these crops. We conducted an extensive literature review of the growing cycle for different crops, identifying the different steps for growing each of the crops and identifying the costs to undertake those actions. The costs used in our analysis are based on the costs that were used in the Sustainable Bioenergy Feedstocks Feasibility Study report for the Department for Business, Energy and Industrial Strategy (BEIS) published in 2021. This report carried out an extensive review of the available information for different types of bioenergy crops. Information was obtained through a literature review, which was supplemented by interviews with a range of key stakeholders, and expert insight from the project team. In addition, insights were gained through a review of development of SRC in Sweden, which has the largest planted area of SRC in the EU. A list of organisations consulted during the stakeholder analysis is given in appendix 2 of the Feedstocks Innovation Study report.

The three scenarios identified in the Feedstocks Innovation Study (low, medium and high-cost scenarios) were used in the analysis. This allows for some variation in factors that affect costs in agriculture and establish hypothetical scenarios that capture different combinations of costs. In the following sections, an overview of the actions and the costs are included for each of the three bioenergy crops;

  • Site preparation / land preparation (including from different prior land-uses where data is available)
  • Establishment / planting
  • Crop management costs e.g., during initial growth
  • Harvesting
  • Reversion (where relevant)

For information on the assumptions on the costs please see the Feedstock Innovation Study.

Miscanthus

For Miscanthus, the cost of production is made up from a number of elements that will be grouped in four phases. The phases for growing Miscanthus are:

  • Site preparation
  • Planting
  • Harvesting
  • Reversion

Figure B‑1 shows an example timeline of the Miscanthus growth cycle.

Figure B‑2 Growing cycle for Miscanthus

 ​

Year -1​

Year 0​

Year 1​

Year 2​

Every 3 years​

Jan​

Existing crop​

Site preparation​

Dormancy/Cut back​

Dormancy​

Harvest​

Feb​

Mar​

Apr​

Planting​

Growth​

Growth​

Growth​

May​

Jun​

Gap filling​

Jul​

Growth​

Aug​

Site preparation​

Sep​

Oct​

Nov​

Senescence​

Senescence​

Senescence/ Harvest​

Senescence​

Dec​

Table B‑1 shows all the input costs for Miscanthus used in this study taken from the Feedstocks Innovation Study adjusted to 2023 prices using the latest GDP deflators[56]. As well as adjusting for inflation, fertiliser costs have been increased using the latest data from AHDB on fertiliser prices[57]. Using this data, costs for fertilisers were adjusted by comparing the average annual increase in fertilisers from 2019 to 2023.

Table B‑1 Input costs for Miscanthus (2023 prices)

Broad action category

Cost element

Unit

Lower

Medium

Higher

Site preparation

Professional costs 1 (Advice on Environmental Impact Assessment)

£/ha

0

120

120

Professional costs 2 (Advice on agronomy)

£/ha

0

0

28

Soil sampling

£/ha

7

7

7

Land rent equivalent

£/ha

0

0

0

Clearance & ploughing

£/ha

89

97

106

Total herbicide / insecticide + application 1

£/ha

57

57

69

Miscellaneous / risk to allow for unforeseen issues in land preparation

£/ha

0

61

180

Planting

Power harrow

£/ha

57

68

68

Pest control incl. rabbit fencing

£/ha

0

0

341

Rhizomes, planting, rolling

£/ha

1533

1987

2271

Fertiliser + application 1

£/ha

18

61

67

Total herbicide + application 2

£/ha

57

66

69

Weed/spray

£/ha

84

93

102

Miscellaneous / risk to allow for unforeseen issues during planting

£/ha

0

57

142

Harvesting

Mowing / cutting

£/ha

79

85

97

Baling (at £12/wet tonne)

£/t

12

14

17

Loading, stacking, storage (at £2/wet tonne)

£/t

2

2

5

Fertiliser + application 2

£/ha

25

157

229

Miscellaneous / risk 2 to allow for unforeseen issues during havesting

£/ha

0

0

102

Reversion

Reversion costs (herbicide + plough)

£/ha

145

153

174

 

Overall Total

 

2143

3025

4105

The broad action category: site preparation category includes costs of establishment. The establishment phase involves preparing the soil for the new crops, acquiring all the plant material, weed control, and planting the crops. In the production phase, the crops are matured and harvested throughout the years. This is the longest phase as it repeats for every harvest and includes all processes related to harvesting and regrowing the crop. The third phase will be reversion, when the plant material is removed, and the field is made available for a new crop (see Figure 13‑1).

There are variabilities and uncertainties related to estimating the production costs for each crop. These may arise for a variety of reasons such as:

  • Differences in soil type and/or condition
  • Differences in climate
  • Differences in farming practices across different companies/farms
  • Differences in end-product requirements/specifications.

In the establishment phase, the first lifecycle stage of Miscanthus, the field is taken care of and prepared for plantation. In our model, we have done this in year -1, with year 0 being the reference year for the plantation of the crops. In year -1, the land is prepared for the plantation of the crops in year 0. Several factors affect the cost of planting such as the site, soil type, and drainage. We have incorporated this variance into our model by modelling for different cost scenarios to reflect different possible cost combinations.

In the high-end cost scenario, we have included a possible pest-control component, such as rabbit-fencing to protect the crops. If needed, the pest control section could possibly be a major cost factor.

A couple of years after planting the Miscanthus crops, the first harvest happens. This first harvest marks the beginning of the production phase, which happens every year for the next 18 years. In the production phase, all steps related to harvesting the Miscanthus yield take place. These include mowing/cutting the plant, baling the harvest, and loading it to be further processed or sold. A margin for miscellaneous costs has also been included in the high-cost scenario. At the end of the crop’s life cycle, the reversion process happens to make the land suitable for other crops.

SRC: In this study, we have considered short-rotation coppice such as poplar and willow, two species which can be used for energy generation. Similar to Miscanthus, we have considered different costing phases that are involved in the process of growing SRC. However, given the differences there are between growing these crops and Miscanthus, the processes will be different, meaning that costs will also differ from Miscanthus. We have considered the following phases in the SRC production process:

  • Pre-planting/land preparation
  • Planting
  • Post-planting
  • Harvesting
  • Reversion

The same as Miscanthus, the costs have been taken from the Feedstocks Innovation Study adjusted for inflation and the fertiliser costs adjusted as explained in the Miscanthus method section (see Figure B‑2).

Figure B‑2 Growing cycle for SRC

 ​

Year -1​

Year 0​

Year 1​

Year 2​

Every 3 years​

Jan​

Existing crop​

Site preparation​

Dormancy/Cut back​

Dormancy​

Harvest​

Feb​

Mar​

Apr​

Planting​

Growth​

Growth​

Growth​

May​

Jun​

Gap filling​

Jul​

Growth​

Aug​

Site preparation​

Sep​

Oct​

Nov​

Senescence​

Senescence​

Senescence/ Harvest​

Senescence​

Dec​

Table B‑2 Range of production costs for SRC (2023 prices)

Broad action category

Cost element

Unit

Lower

Medium

Higher

Pre-planting/land preparation

Professional costs 1 for EIA advice

£/ha

0

127

127

Professional costs 2 for agronomy advice

£/ha

0

28

28

Soil sampling and testing 1

£/ha

7

7

7

Soil sampling and testing 2

£/ha

7

7

7

Land rent equivalent

£/ha

0

0

0

Total herbicide plus application 1

£/ha

57

57

60

Land prep (ploughing)

£/ha

89

97

106

Land prep (power harrow)

£/ha

61

69

75

Land prep (miscellaneous / risks)

£/ha

34

68

103

Pest protection (rabbit fencing)

£/ha

0

341

341

Fertiliser + application 1

£/ha

18

112

164

Planting

Plant material

£/ha

1107

1249

1419

Planting

£/ha

454

454

511

Fertiliser + application 2

£/ha

18

112

164

Total herbicide plus application 2

£/ha

57

57

60

Post-planting

Herbicide / weed / spray 1

£/ha

84

93

93

Gapping up

£/ha

15

17

19

Cutback / mowing

£/ha

51

57

62

Harvesting and storage

Harvesting, handling and storage

£/ha

710

823

852

Fertiliser + application 3

£/ha

18

112

164

Herbicide / weed / spray 2

£/ha

84

102

102

Other annual costs

Miscellaneous / risks

£/ha

11

23

34

Reversion costs

£/ha

341

341

511

 

Overall Total

£/ha

3,242

4,301

4,911

In the pre-planting stage, the land is prepared for growing the SRC crop. Similar to Miscanthus, in the land preparation stage different steps to prepare the land such as soil sampling and testing, ploughing, and power harrow take place. We have modelled these to happen in year -1, with year 0 being the year in which planting takes place. Heavier or more compacted soils will require additional ploughing and sub-soiling compared to lighter costs. Multiple herbicide applications may be needed depending on the specific circumstances. A rabbit fence or other forms of pest control might be needed.

In the planting phase, costs for the plant material and other costs involved in the planting process (such as labour costs and fuel costs) are taken into consideration as well as the costs for soil fertilisation and herbicide application. Fertiliser will be applied either by the farmer or a contractor after planting in and around the plants. Fertiliser could be a purchased product or sewage sludge (if permitted) which comes at zero cost.

In the post-planting phase, the farmer maintains the plants to ensure the plants are healthy and the soil usage is being optimised. At the end of third year when the leaves have fallen, the farmer will apply herbicide and cut back the crop to encourage the plant to grow more stems and fill any gaps in the crop with new, larger size rods which can compete with the already established plants which have just been cut back. In this phase, the farmer also cuts the emerging shoots to encourage more shoots per plant.

Once the plants are ready for harvest, the harvesting process begins. We have combined all the different costs (machinery, labour, fuel, handling, storage, etc) into a single category as there would be too much granularity if we considered them separately. After each harvest, the application of fertiliser and weed/spraying takes place. We have also allowed for possible miscellaneous costs which could affect the final cost of this process.

Short Rotation Forestry (SRF)

Two scenarios have been defined for SRF:

  • SRF conifer scenario
  • SRF broadleaved scenario

As with Miscanthus and SRC the costs for SRF have been taken from the Sustainable Bioenergy Feedstocks Feasibility Study report for the Department for Business, Energy and Industrial Strategy (BEIS) published in 2021. The costs have been adjusted for inflation to 2023 prices using the latest GDP deflators[58].

A low, medium and high scenario for both SRF broadleaved and SRF conifer are included.

For the SRF broadleaved scenario, the costs are based on fast growing native broadleaves on medium quality land in lowlands, grown without thinning on a 15- to 20-year rotation and harvested conventionally as pole length or shortwood. The lower cost outcome uses fast growing poplar on farmland, whereas the medium and higher cost outcomes use birch in forest conditions. For more information on the costs please see the Feasibility Study. Details on the costs can be found in Table 13‑4. For the SRF conifer scenario, the costs are on the basis on a fast-growing conifer species (e.g., Sitka Spruce) on medium quality land, grown without thinning on a 15 to 20-year rotation and harvested conventionally as pole length or shortwood. The lower cost outcome assumes new planting, whereas the medium and higher cost outcome assume restocking in forest conditions. For all costs, please see Table B‑5.

Table B‑3 Range of production costs for broadleaved short rotation (2023 prices)

Broad action category

Cost element

Unit

Lower

Medium

Higher

Ground preparation

Deer fencing

£/ha

0

727

965

Rabbit control

£/ha

0

79

119

Spirals

£/ha

710

0

0

Draining

£/ha

0

45

85

Cultivation

£/ha

51

170

369

Planting

Plant supply

£/ha

1079

937

1516

Planting, restock

£/ha

0

250

443

Planting, New

£/ha

97

0

0

Beat up, Labour & plants

£/ha

125

392

766

Establishment and maintenance

Top up Spray (Hylobius)

£/ha

0

0

0

Weeding

£/ha

199

352

505

Cleaning/respacing

£/ha

0

0

51

General maintenance

£/ha

182

250

312

Forest-scale operations

£/ha

51

62

91

Management overhead

£/ha

0

0

0

Land rent equivalent

£/ha

0

149

206

Harvesting

Thinning

£/ha

0

0

0

Clearfell

£/odt

5

7

8

Residue removal

£/ha

0

0

0

Comminution (chipping)

£/odt

3

6

9

Reversion

Reversion

£/ha

1136

1419

1817

 

Overall Total

£/ha

3628

4833

7246

Table B4 Range of production costs for conifer short rotation (2023 prices)

Broad action category

Cost element

Unit

Lower

Medium

Higher

 

Deer fencing

£/ha

0

290

647

Rabbit control

£/ha

0

0

0

Spirals

£/ha

0

0

0

Draining

£/ha

0

45

85

Cultivation

£/ha

170

250

466

Planting

Plant supply

£/ha

676

738

1022

Planting, restock

£/ha

0

227

312

Planting, New

£/ha

153

0

0

Beat up, Labour & plants

£/ha

193

386

562

Establishment and maintenance

Top up Spray (Hylobius)

£/ha

0

102

261

Weeding

£/ha

165

324

432

Cleaning/respacing

£/ha

0

79

119

General maintenance

£/ha

182

250

312

Forest-scale operations

£/ha

51

62

91

Management overhead

£/ha

0

0

0

Harvesting

Thinning

£/ha

0

0

0

Clearfell

£/odt

5

7

8

Residue removal

£/ha

0

0

0

Comminution (chipping)

£/odt

3

6

9

Reversion

Reversion

£/ha

1136

1419

1817

 

Overall Total

£/ha

2700

4180

6135

Step 2: Calculating the output (yield and price)

Miscanthus

Data for yields in Scotland were obtained from the Scottish farm management handbook. Similar to what has been done in the costing section, different scenarios have been considered in order to account for possible variance in yields. 12 ODT, 14 ODT and 15 ODT were used for the low, medium and high scenario, respectively. ODT/ha stands for Oven dry tonne per hectare and corresponds to the total amount of above-ground living organic matter produced in a single hectare. Harvesting takes place in year 3 and is harvested on annual basis. Pricing data for Miscanthus was obtained from the John Nix pocketbook, £95, £97, £98 £/odt for the lower, medium and higher scenario, respectively (adjusted from 2021 to 2023 prices using the latest GDP deflators). This value is taken from the value that is offered to farmers from Terravesta. There are penalties if the crop is out of specification and bonuses available of £2/tonne if bales have been stored in a barn.

SRC

SRC is harvested with 2–3-year intervals and similar to Miscanthus, yields can vary for a wide range of reasons such as site conditions, type of planting method, years since planting, crop type, orography, and weather conditions. The yields used in the analysis come from the official statistics published by Defra which looks at Plant biomass: Miscanthus, short rotation coppice and straw[59]. These are 24, 35, 45 odt/ha, respectively. In the analysis, fluctuations in the yield of SRC have been included (Table ‑6).

Table B5 SRC rotation used in analysis if assuming fluctuations take place

Year

Units

Lower

Medium

Higher

Year 1

odt/ha

 

 

 

Year 2

odt/ha

 

 

 

Year 3

odt/ha

20

29

38

Year 4

odt/ha

 

 

 

Year 5

odt/ha

 

 

 

Year 6

odt/ha

26

38

49

Year 7

odt/ha

 

 

 

Year 8

odt/ha

 

 

 

Year 9

odt/ha

26

38

49

Year 10

odt/ha

 

 

 

Year 11

odt/ha

 

 

 

Year 12

odt/ha

26

38

49

Year 13

odt/ha

 

 

 

Year 14

odt/ha

 

 

 

Year 15

odt/ha

25

35

46

Year 16

odt/ha

 

 

 

Year 17

odt/ha

 

 

 

Year 18

odt/ha

23

33

43

Year 19

odt/ha

 

 

 

Year 20

odt/ha

 

 

 

Year 21

odt/ha

21

31

40

For the price of SRC, the value used in the latest John Nixs Pocketbook (2022) has been used. Adjusted to 2023 prices this is £59 per odt. This figure is based on what a grower in Cumbria could get.

SRF

SRF is harvested at 15-year intervals for both conifer (sikca spruce) and broadleaved (silver birch). The yield estimates were taken from the Feedstock Innovation Study. The price for both types of SRF were taken from a stakeholder from Scottish Forestry, which estimated that the payment for SRF that had been stacked and cut would be between £50 to £64.

Step 3: Calculating the gross margin

To calculate the gross margins for the bioenergy crops, firstly the costs were placed over the lifetime of the crop. For example, clearance and ploughing costs for Miscanthus were included in the first year (-1). The accompanying spreadsheet shows how all the costs are spread over the lifecycle of the crop. The costs were then taken away from the output estimates to calculate the gross margins over the lifecycle of the crop.

To calculate the gross margins for all the farm types used in the analysis the latest data from the Scotland farm business survey[60] was used using data from the years 2016 to 2022. An average over these years was used to take account of variability in agricultural costs and outputs. To get to the £ per hectare value, using the time series data from 2016, total average output for each of the farm types was divided by the average size of the farm. For variable costs, total average inputs – other fixed costs were taken away from the total average inputs to get to the variable costs. This was then converted to per hectare values. For the general cropping, forage category data was taken from the latest census[61] for the output data and the costs were taken from the farm management handbook[62].

Table C: Breakdown of costs and outputs used for gross margin calculations (average data from 6 years from 2016-17 to 2021-22 from Scottish Farm Business Income Survey)

Type of farm

Lowland Sheep & Cattle

Mixed

Performance band

Lower 25%

Average

Upper 25%

Lower 25%

Average

Upper 25%

Total crop output

10,516

22,962

48,895

73,507

102,314

180,117

Total livestock output

74,755

126,232

304,160

72,675

104,739

165,523

Miscellaneous output

7,184

8,973

11,508

13,028

20,741

50,036

Total average output

92,455

158,167

364,563

159,210

227,793

395,676

Crop expenses

15,097

20,175

38,586

37,388

45,197

67,023

Livestock expenses

42,485

62,298

142,947

41,068

52,412

73,146

Other fixed costs

92,125

91,391

151,465

133,423

146,043

208,434

Total average inputs

149,707

173,864

332,999

211,879

243,652

348,603

Total average inputs – other fixed costs

57,582

82,473

181,534

78,457

97,609

140,169

Table D: General cropping – forage gross margin calculation data

 

Arable silage

forage maize

Whole winter wheat fermented

Whole winter wheat cracked

Average

Total

Total cost per annum (£/ha)[63]

1,193

1,113

1,441

1,625

1,343

 

General cropping – forage output (£/ha)[64]

     

58

Gross margin (£/ha)

     

1285

Gross margin calculation: Average total cost per annum – forage output = gross margin

Figure A: Excerpt from Scottish Farm Mangement Handbook showing data used in the calculations in Table D above.

Comparing bioenergy crops to existing land-use economics: three scenarios

Bioenergy energy crop scenarios

For the low scenario, high costs were compared with lower output. For the medium scenario, medium costs were compared with medium output. For the high scenario, low costs were compared with high output.

Farm scenarios

For the different farm income scenarios, the farm business income definitions were used from the Scotland farm business survey. For low this uses the lower 25% percentile for that farm category, for medium the average percentile was used and for the higher, the upper 25% percentile was used.

Yearly average gross margins for each of the bioenergy crops and farm types

To calculate the yearly average gross margins for each of the bioenergy crop and the farm type scenarios a discount rate was applied to future years. The discount rate applied is the standard discount rate recommended by the green book[65]. The Green Book recommends that costs and benefits occurring in the first 30 years of a programme, project or policy be discounted at an annual rate of 3.5%, and recommends a schedule of declining discount rates thereafter. A discount rate is applied as it is assumed that people prefer to receive financial outputs now rather then in the future.

Assessment of implications for Scotland’s rural economy

Using the geo-spatial mapping data from the previous project, which identified land that was theoretically suitable for PEC production considering land capability, slope, and climate (Martin et al, 2020), percentages of the land that could be converted to bioenergy crops were derived for each of the regions. This percentage was then applied to the land area estimated to be in each farm type in the region, to derive the land are potentially suitable for PECs by farm type. The land area in each farm type in each region was estimated by combining data on crop areas in each region with estimates of the percentge of crop area at the Scottish level which occurs in each each farm type.

A previous CXC study (Meek et al, 2022) indicated that, bearing in mind land suitability, an estimated total of approximately 27,000 ha PECs could be planted by 2030, 38,000 by 2032 and 90,250 hectares by 2045. Two scenarios were then constructed to see what land transitions could meet these areas of PECS. Using information on the gross margins for the three farm types of interest and the gross margins for the PECs, the economic impact of each land use change can be ranked.

Table E Change in gross margin (£/ha) in transitioning to PECs

 

SRF

SRC

Miscanthus

Non-LFA Cattle & Sheep

-£414

-£347

-£52

Mixed holdings

-£577

-£511

-£215

General cropping

£1,009

£1,076

£1,371

These rankings were used to guide how much of the potential land suitable for PECs in each farm type was assumed to be converted, with more land converted for more economically beneficial transitions. Care was also taken, particularly in Scenario 2, where high levels of trnaition are needed to meet the higher PEC target area, that levels of overall change were not too high. This resulted in the assumed changes shown in the Tables below

Table F Assumed changes in land use Scenario 1

 

Percentage of suitable land assumed converted to PECs

Ha converted to PECs

 

Non-LFA Cattle & Sheep

Mixed Holdings

General Cropping, Forage

Non-LFA Cattle & Sheep

Mixed Holdings

General Cropping, Forage

Total area

 PEC

 

 

 

ha

ha

ha

ha

SRF

15%

 

66%

9,928

8,977

18,905

SRC

15%

 

66%

7,578

5,258

12,836

Miscanthus

30%

 

100%

3,790

1,352

5,142

Total land are converted

21,296

15,587

36,883

Percentage of total land in farm type converted

20%

0%

1.1%

2.1%

Table G Assumed changes in land use Scenario 2

 

Percentage of suitable land assumed converted to PECs

Ha converted to PECs

PEC

Non-LFA Cattle & Sheep

Mixed Holdings

General Cropping, Forage

Non-LFA Cattle & Sheep

Mixed Holdings

General Cropping, Forage

Total area

 

 

 

 

ha

ha

ha

ha

SRF

30%

50%

75%

19,857

13,873

10,201

43,931

SRC

30%

50%

75%

15,156

10,078

5,975

31,209

Miscanthus

60%

100%

100%

7,580

4,770

1,352

13,701

Total land are converted

21,296

15,587

42,592

Percentage of total land in farm type converted

40%

9%

1.3%

5.0%

The Potential change in farm income due to change in gross margin was calculated by multiplying the change in gross margin from each transition in Tables E, with the areas in transition in Tables F and G. This was done on a regional basis.

The estimated shortfall in crop production from a shift to PECs, was calculated by using data on the areas of crop land in each farm type and the areas converted to PECs to calculate lost areas of crop production. These were then multiplied by typical crop yields[66]. This was all done at a regional level. Estimate the change in livestock production that might come from the shift to PECs would require a more detailed analysis than was possible in this study.

Appendix F: Mapping outputs from 2020 project

A previous CXC Project (Martin et al, 2020) used geo-spatial mapping to identify suitable areas of land in Scotland for growing PECs. The project focused on land capability of grades; 4.1, 4.2, 5.1, 5.2, 5.3 and 6.1, which are typically suitable for mixed agriculture, improved grassland and high-quality rough grazing [67], and assessed what area of these grades where suitable for SRC and Miscanthus growth which limited the potential production area. For SRF the assessment also included land capability for agriculture grades F1, F2, F3, F4 and F5.

Figure C-1: Distribution of suitable land available for Short Rotation Forestry

Map of Scotland showing land suitable for Short Rotation Forestry, mostly located along the Eastern side of the country.

 

Figure C-2: Distribution of suitable land available for Short Rotation Coppice

Map of Scotland showing land suitable for growing Short Rotation Coppice. As with Short Rotation Forestry, this is mostly in the Eastern Part of the country but with small area of land.

 

Figure C-3: Distribution of suitable land available for Miscanthus

Map of Scotland showing land suitable for growing Miscanthus. A very small suitable area, scattered across the country in small patches.

Data attributions

The data used in the bioenergy crop growth analysis was downloaded from multiple sources. In order to comply with their licences, as well as to acknowledge the use of the data, attributions for each data source is provided in Table C-1. In all cases these attributions are those directly required by the data licence or metadata.

Table C-1: Data attributions

Dataset name and data source

Data attribution

James Hutton Institute: Land Capability for Agriculture, 1:250,000

James Hutton Institute: Land Capability for Agriculture, 1:250,000 copyright and database right The James Hutton Institute 1980. Used with permission of The James Hutton Institute. All rights reserved.

Any public sector information contained in these data is licensed under the Open Government Licence v.2.0

James Hutton Institute: Land Capability for Forestry, 1:250,000

James Hutton Institute: Land Capability for Forestry, 1:250,000 copyright and database right The James Hutton Institute 1980. Used with permission of The James Hutton Institute. All rights reserved.

Any public sector information contained in these data is licensed under the Open Government Licence v.2.0

Ordnance Survey: Terrain 50 50m resolution digital elevation model

Contains OS data © Crown Copyright [and database right] (2019).

Ecological Site Classification

Forestry Commission, (2019).

Centre for Ecology and Hydrology: Gridded Estimates of Areal Rainfall (GEAR)

Tanguy, M.; Dixon, H.; Prosdocimi, I.; Morris, D.G.; Keller, V.D.J. (2019). Gridded estimates of daily and monthly areal rainfall for the United Kingdom (1890-2017) [CEH-GEAR]. NERC Environmental Information Data Centre. https://doi.org/10.5285/ee9ab43d-a4fe-4e73-afd5-cd4fc4c82556

Centre for Ecology and Hydrology: Climate Hydrology and Ecology Research Support System (CHESS)

Martinez-de la Torre, A.; Blyth, E.M.; Robinson, E.L. (2018). Water, carbon and energy fluxes simulation for Great Britain using the JULES Land Surface Model and the Climate Hydrology and Ecology research Support System meteorology dataset (1961-2015) [CHESS-land]. NERC Environmental Information Data Centre. https://doi.org/10.5285/c76096d6-45d4-4a69-a310-4c67f8dcf096

James Hutton Institute: National Soils of Scotland, 1:250,000

James Hutton Institute: National Soils of Scotland, 1:250,000 copyright and database right The James Hutton Institute 2019. Used with permission of The James Hutton Institute. All rights reserved.

Any public sector information contained in these data is licensed under the Open Government Licence v.2.0

Scottish Natural Heritage: Carbon and Peatland Map 2016.

Contains public sector information licensed under the Open Government Licence v3.0.

Forestry Commission: National Forestry Inventory Woodland Scotland 2017

Contains Forestry Commission information licensed under the Open Government License v3.0.

European Space Agency: CORINE 2018

© European Union, Copernicus Land Monitoring Service 2019, European Environment Agency (EEA)

Ordnance Survey: Open Zoomstack

Contains OS data © Crown Copyright [and database right] (2019).

Scottish Natural Heritage: National Parks, National Scenic Areas, Country Parks etc.

Contains public sector information licensed under the Open Government Licence v3.0.

Scottish Natural Heritage: World Heritage Sites, Battlefields, Conservation Areas etc.

Contains public sector information licensed under the Open Government Licence v3.0.

Scottish Natural Heritage: Ramsar, SAC, SPA, SSSI etc.

Contains public sector information licensed under the Open Government Licence v3.0.

AppendixG: Methology for geospatial analysis of agricultural land use change

Geospatial analysis

To calculate the current land area available for change to bioenergy cropping, based on the locations from the previous CXC project, geospatial analysis was completed. The percentage of the total land area suitable for bioenergy growth in each agricultural region was calculated and applied to the total hectarage of the the agricultural land used within the land capability categories. This was then divided into three main farm types: Non-LFA cattle and sheep, Mixed holdings, General cropping – forage. This presented a total hectarage by agricultural region and farm type that could be converted to SRC, Miscanthus and SRF. This data was used in economic calculations to present the change in economic potential for the three farm types under a land use change to bioenergy crops. Details of sources used are presented in Table D-1.

Table D‑1 Data sources and usage

Data type

Source

Reference

Usage

Assumption

Table 14 Land Use by Region Dataset

Scottish Agricultural Census June 2021

agricultural-census-june-2021-tables.xlsx

Hectarage of barley (spring and winter), stockfeeding crops (maize and lupin) and grass (under 5 years old, and 5 years old and over) used to calculate the current land usage within the Scottish agricultural regions.

N/A

Table 17 Livestock by Region (Number of heads) Dataset

Scottish Agricultural Census June 2021

agricultural-census-june-2021-tables.xlsx

Data used to calculate the percentage split of the number of animals using grass (hay and silage) within Scotland.

Assumption that beef and dairy cattle will consume similar feed amounts each day, supported by review or recommended dry matter intake by online sources.

Table 1 Crops and grass area, hay and silage production, 2010 to 2020

Agricultural Statistics: Results of December 2020 Agricultural Survey

agricultural-statistics-december-2020.xlsx

Data used to calculate the percentage split of grass cut for hay and silage.

Assumption that all grass yield would match yields of hay and silage crops.

Table 1b. Agricultural area in hectares, 2011 to 2021

Scottish Agricultural Census June 2021

agricultural-census-june-2021-tables.xlsx

Data used to calculate the percentage split of stockfeeding crops between maize and lupin.

Only Maize and Lupin stockfeeding crops have been included as these have been named in the Table 14 footnote.

Barley usage in Scotland

NFU Scotland: What we produce

https://www.nfus.org.uk/farming-facts/what-we-produce.aspx

Data used to calculate the percentage of barley produced in Scotland used for animal feed.

Assumed that all barley produced for animal feed is produced in land capability categories 3.3-5.3, in line with the areas selected for potential growth of SRC and Miscanthus.

Land capability – agriculture

James Hutton Institute: Land Capability for Agriculture, 1:250,000

https://www.hutton.ac.uk/learning/exploringscotland/land-capability-agriculture-scotland

Dataset used to compare the land capability categories against the potential growth area of SRC and Miscanthus to calculate the percentage of land area for bioenergy growth applied in calculations.

 

Land capability – forestry

James Hutton Institute: Land Capability for Forestry, 1:250,000

https://www.hutton.ac.uk/learning/natural-resource-datasets/landcover/land-capability-forestry

Dataset used to compare the land capability categories against the potential growth area of SRF to calculate the percentage of land area for bioenergy growth applied in calculations.

 

Percentage of crops by farm type

Technical knowledge

 

Division of crops between farm types used to split the total hectarage of crops into three main farm type categories: Non-LFA cattle and sheep, Mixed holdings, General cropping – forage for economic farm level analysis.

Assumptions have been made on the percentage split of the crops focused within the mixed agriculture and improved grassland land capability categories, based on the removal of total crops used for other farm types (e.g. specialist dairy and non-animal feed cropping categories – general cropping and specialist cereals).

Appendix H: Stakeholder engagement methodology and key findings

In addition to the rapid evidence assessment and economic analysis, we conducted stakeholder engagement with a robust representative sample of stakeholders from across the Scottish agricultural network to provide input into the project. The engagement was conducted in two stages: 

  1. Topic expert research interviews: eight semi-structured interviews of approx. one hr were carried out as part of the evidence gathering process. Interviewees were sent a briefing of key areas of enquiry prior to their interview to aid their preparation. Ricardo recorded each discussion as meeting recording, transcript and attendee notes.

 

  1. Stakeholder workshop: Stakeholder input was sought to scrutinise findings and ensure the SWOT and PESTLE are as complete and robust as possible.  This engagement was delivered through a one hour structured on-line meeting held on the 16th October 2023 with a combination of stakeholders who had already contributed to individual interviews and representatives of wider organisation and businesses. Initial finding were presented by the project team and comment on accuracy, completeness and additional considerations sought throughout. 
    Following the meeting, the presentation and list of questions (below) was sent to all attendees with an invitation for follow up comment. 

Insights were gained into:

  • What influences farmer and land-manager decisions on energy cropping.
  • Wider concerns or questions about potential implications.
  • Benefits and disadvantages of energy crops.
  • Opportunities to drive greater uptake.
  • Insights in economic aspects and state of knowledge on this for Scotland in particular.

Feedback reflected some of the points of discussion and debate that were identified in the REA such as questions over what land is suitable and how best to use land given Scotland’s climate targets and other priorities, and debate over yields, prices and how to ensure wider environmental benefits from energy crops, and to what extent this is possible in Scotland.

The insights from this stakeholder engagement have been integrated into Section 4 Evidence Base and Section 7 SWOT & PESTLE analysis.

Summary of questions posed to stakeholders during the engagement element of the project: 

General: 

  • Do you think there are opportunities for farmers and land managers in Scotland to benefit from producing perennial energy crops? 
  • If so, which crops, locations and circumstances do you think could be most economically viable, and why?  
  • How could we improve our costings and economic assumptions to make them more reflective of the reality of the Scottish context? 
  • What economic and other considerations would most influence farmers’ and land-managers’ decision to start producing energy crops? 
  • What are the most significant potential benefits and challenges at a wider economy scale?  

 Economic analysis at farm scale 

  • How could we improve our costings and economic assumptions to make them more reflective of the reality of the Scottish context? 
  • Would you suggest any adjustments to our costs?   
  • Would you suggest any adjustment to our yield or prices? 
  • Are the rotation lengths appropriate?  

 Preferred locations 

  • How is best to select preferred biomass locations? E.g. based on areas in proximity to market usage? Or based on land with best production potential? 
  • Are there any existing or proposed large-scale biomass plants in Scotland? 
  • What is a maximum travel distance from farm to plant? 
  • Are there any key biomass planting / harvesting contractors in Scotland? If so, where? 

 

Output of Stakeholder Engagement 

The output of the stakeholder interviews included suggestions for data and information sources to support the economic analysis. Stakeholders also provided commentary on the opportunities and challenges of perennial energy crop production in Scotland; this is summarized below: 

 

Miscanthus 

Short Rotation Coppice 

Short Rotation Forestry 

Low input & maintenance costs 

Use existing harvester (maize harvester) 

Alternative markets (eg bedding) 

Earlier harvest income than SRC/SRF & annual harvest 

Knowledge base/innovation pipeline 

Harvest contractor employment 

Soil health 

Sequential planting to allow harvest every year (albeit small volumes) 

Opportunity to improve efficiency with modern machinery 

Potential for biodiversity net gain / natural capital payments 

Soil health / shelter benefits for other enterprises on farm. 

No costs whilst growing 

Alternative markets (for same diameter wood/ maybe to grow on) 

Suits wider range of conditions 

Potential community involvement 

Shelter for livestock / crops 

Poor cashflow 

 

Miscanthus 

Short Rotation Coppice 

Short Rotation Forestry 

Upfront cost: 2-3yrs to harvest 

Winter hardiness challenge (although new cultivars being developed) 

Land-use change carbon stock 

Challenge sourcing planting stock 

Need access to drying / chipping 

Farmers consider financially risky 

Limits rotation flexibility 

Risk of sharing neighbour crop 

Pests: willow rust 

Yield uncertain over lifetime 

Need access to drying / chipping 

Change of land-use/payment lost 

Limits rotation flexibility 

Risk of sharing neighbour crop 

Longest period before harvest 

Less research in Scotland 

Competition for wood output 

 Individual stakeholder interviews:

Crops4Energy

Kevin Lindegaard 

Director of Crops for Energy

Eadha Enterprises

Peter Livingstone

CEO

NatureScot

Cécile Smith

Climate Change & Land Use Adviser

NatureScot

Kirsty Hutchison

Agricultural Officer | Natural Resource Management

NFUS

David Michie

Crop Policy Lead

NFUS

Kate Hopper

Policy Manage Climate Change

Scottish Forestry

Jason Hubert

Head of Forest Sector Development

Willow Energy

Jamie Rickerby

Director

Stakeholder online workshop attendees:

Scottish Land and Estates

Terravesta

Crown Estate Scotland

SRUC/BiomassConnect

CONFOR

SEPA

NFUS

AHDB

Willow Energy

CAAV

SOAS

Crops4Energy

Scottish Forestry

Director of International Land Use Study Centre – James Hutton Institute

NatureScot

AHDB

Scottish Land and Estates

Appendix I: Biomass Feedstock Innovation Funding in the UK

There is currently significant investment in innovation to increase the production of sustainable domestic biomass, including the Biomass Feedstocks Innovation Programme[68], which is funding innovative ideas that address barriers to biomass feedstock production across the UK. It is supporting projects those seeking to improve productivity through breeding, planting, cultivating and harvesting. Summaries of the 12 funded projects, taken from the GOV.UK programme page, are given below[69].

  1. Biomass Connect: Biomass Innovation and Information

Led by UK Centre for Ecology & Hydrology. The Biomass Connect Phase 2 project will create a demonstration and knowledge sharing platform to showcase best practice and innovations in land-based biomass feedstock production.

  • Project BIOFORCE (BIOmass FORestry CrEation): Creating geospatial data systems to upscale national forestry-based biomass production.

Led by Verna Earth Solutions Ltd (formerly Forest Creation Partners Limited). Project BIOFORCE will create and demonstrate new, upgraded versions of Forest Research’s industry-standard Ecological Site Classification (ESC) tool, and Verna’s successful ForestFounder system.

  • Transforming UK offshore marine algae biomass production

Led by SeaGrown Limited. Scarborough-based SeaGrown operates a 25-hectare offshore seaweed farm in the North Sea off the Yorkshire Coast. This project seeks to apply SeaGrown’s experience in pioneering this new sector to create an innovative, automated end-to-end seaweed farming system.

  1. EnviroCrops – Perennial Energy Crops Decision Support System (PEC-DSS)

Led by Agri Food and Biosciences Institute (AFBI).The EnviroCrops web app is envisaged as a central source of impartial information in an easy to access, free or low-cost, user-friendly format, that will enable farmers, land managers and consultants to make an informed decision about planting biomass crops.

  1. Miscanspeed – accelerating Miscanthus breeding using genomic selection.

Led by Aberystwyth University. The aim of this project is to demonstrate the application of genomic selection (GS) in accelerating the breeding of high yielding, resilient Miscanthus varieties for the UK.

  • Technologies to enhance the multiplication and propagation of energy crops (TEMPEC)

Led by New Energy Farms EU Limited. The project objectives are to increase the number of energy grass varieties that are available, increase yield and develop agronomic improvements to multiplying and planting energy crops.

  • Optimising Miscanthus Establishment through improved mechanisation and data capture to meet Net Zero targets (OMENZ)

Led by Terravesta Farms Ltd. The project will utilise the Terravesta Harvest Hub platform to integrate data collected from all stages of our establishment pipeline alongside their existing harvest and growth data. Through data integration with the current supply chain, the OMENZ team will gain insights into long term crop performance and improve the entire Miscanthus biomass supply chain, benefiting both growers and end-users.

  • Demonstration of on-­farm pelletisation technology.

Led by White Horse Energy Ltd in developing and constructing a robust mobile pelletiser enabling farms to process a range of feedstocks, enabling domestic biomass pellets to displace imported pellets in the UK energy supply mix.

  • Teesdale Moorland Biomass Project

Led by Teesdale Environmental Consulting Ltd (TEC Ltd). The Teesdale Moorland Biomass Project aims to utilise existing managed heather moort and harvest commercially viable biomass products from naturally generated moorland crops that are currently burned in situ as part of annual land management practices.

  1. Taeda Tech Project – Soilless cultivation for rapid biomass feedstock production

Led by University of Surrey. The project uses novel aeroponic technology to rapidly cultivate Short Rotation Coppice (SRC) willow cuttings which can be planted into the field for bioenergy.

  • Net Zero Willow

Led by Rickerby Estates Ltd. The team is developing innovations aimed at revolutionising the industry and maximising marginal gains through more efficient machinery.

  1. Accelerating Willow Breeding and Deployment

Led by Rothamsted Research. The Accelerating Willow Breeding and Deployment (AWBD) project will accelerate the breeding of SRC willow and generate information to guide the intelligent deployment of current varieties. 

 

Appendix J: SWOT and PESTLE Analysis: Detailed Results

The SWOT analysis assessed the current economic potential for perennial energy crops for farmers and land-managers in Scotland, looking at strengths, weaknesses, opportunities, and threats (SWOT) to provide a simplified picture and more clarity of what would be needed in order for these crops to be an attractive proposition economically, whilst also considering the other factors which farmers and land-managers would be likely to consider alongside the economics. The SWOT tables below are grouped according to the following categorisations:

  • Perennial energy grasses (primarily Miscanthus);
  • Short rotation coppice (primarily Willow);
  • Short rotation forestry (including broadleaved; conifer)

Table G1. SWOT table covering Perennial energy grasses, focused on Miscanthus.

Strengths

Weaknesses

  • Can harvest with maize harvester – farmer / contractor will have this (but not many people grow maize in Scotland).
    • Alternative markets e.g. bedding provides more security for farmers to encourage adoption.
    • Early harvest, better cashflow for farmers – 3yrs to first harvest (but some small harvest in first year)
    • Knowledge gaps – not flagged in research.
    • Limited input needs – lower costs
  • Upfront investment; delay in income (2-3yrs)
  • Winter hardiness (Scotland);
  • Gap in support e.g. grants (energy crop scheme for establishment grants in early 2000s) – nothing right now.
  • Limited market right now, uncertainty for future market.
  • Higher yield than SRC
  • Doesn’t respond to N fertilizer – limited opportunity to boost yield
  • Not frost tolerant – less suited to Scotland. But there are more frost hardy cultivars being developed.

Opportunities

Threats

    • To incentivise with grants, as there are none right now;
    • Employment opportunity in harvesting contracting.
    • Biodegradable film mulch – can boost economic performance; other innovations under biomass feedstock – opportunity to take these up (e.g. hybrid varieties which are more
    • Grassland that is becoming unprofitable – could be used.
  • Loss of carbon stock through land-use change (eg. if convert grassland)
  • Challenges in sourcing high-quality planting stock (esp. if there is uptake in planting)

Table G2. SWOT table covering Short Rotation Coppice

Strengths

Weaknesses

  • Sequential planting; allows harvest every year. But limits economics with small amounts.
  • Farmers consider financially risky; low selling price; high cost of harvest.
  • Low selling price / high harvest costs.
  • Single market for energy
  • Focused on a small number of species – more data needed on e.g. aspen
  • Concern re. removal of flexibility of land use in a rotation
  • Challenges around growth area (willow won’t grow well everywhere)

Opportunities

Threats

  • Modern machinery can improve efficiency.
  • Breeding to achieve higher yields happening.
  • Opportunities for biodiversity net gain and natural capital
  • Additional benefits of woodland habitat linkage
  • Benefits as a neighbour crop for shelter
  • Soil health benefits of willow?
  • Purification of contaminated soils? (willow)
  • Variable yield / uncertainty over lifecycle.
  • Risks as a neighbour crop for shading
  • Risks of pest (rust) for SRC willow

Table G3. SWOT table covering Short Rotation Forestry

Strengths

Weaknesses

  • No costs whilst growing – to harvest point.
  • Alternative markets potentially for same small diameter wood.
  • Wider range of growing conditions
  • Longer growing period before harvest.
  • Need to replant after harvest.
  • Loss of ‘agriculture’ classification as land and resulting loss of farm subsidy payment.
  • Less research: only the Forest Research plots – a few years ago, but not yet got full result.
  • Storage / transport: particularly for SRF in research (check)
  • Concern re. removal of flexibility of land use in a rotation

Opportunities

Threats

  • Variable yield / uncertainty over lifecycle.
  • Community-scale growth plans and ownership: potential economic driver for socio-economic regeneration
  • Biodiversity/conservation/amenity value
  • Grazing options on planted land and animal welfare benefits
  • Benefits as a neighbour crop for shelter
  • Options for diversification/flexibility through growing on to larger trees for other uses (e.g. timber)
  • Competition for output for other (possible more profitable) wood uses, such as timber
  • Risks as a neighbour crop for shading

PESTLE Analysis of economic potential of energy crops in Scotland

Energy crops are subject to a range of enabling and preventative factors which would influence the benefits and potential uptake of the crops in Scotland. A political, economic, social, technical, legal, and environmental (PESTLE) analysis was therefore undertaken to assess the potential to…increase economic viability and uptake of energy crops in Scotland This assessment was produced following the SWOT analysis to incorporate the strengths and opportunities of each energy crops (and more generally) identified in the SWOT.

Table G4. Summary PESTLE Analysis: enabling and preventative factors for economically viable energy crops in Scotland

The combination of high production costs, particularly the upfront investments uncertain policies and uncertain market prices for future harvests discourage farmers from growing SRC plants. (Zięty et al, 2022)

 

ENABLER  

BARRIER 

Political  

 

  • Uncertain policies /lack of political support for key energy crops over multiple governments (Zięty et al, 2022, Davies et al, 2020) For example, the Energy Crops Scheme which provided establishment grants was withdrawn in 2013, and despite strong lobbying, Defra had resisted allowing Miscanthus to be counted as an ecological focus area (EFA) under greening.
  • Lack of specific grant funding available to help pay for establishment Miscanthus (Davies 2020).
  • The combination of high production costs and uncertain policies as well as the prices of the products discourage farmers from growing SRC plants. (Zięty et al, 2022)

Economic 

  • Miscanthus- ‘high return per hectare’ (Martin et al., 2020 D1) 
  • Yield and sale price are biggest contributing factors to achieving good economics (Martin et al., 2020 D1) 
  • Farmers currently growing a bioenergy crop also had a higher average income compared to their nongrowing counterparts. (Brown et al 2016 D2) 
  • Establishment grants and cash advance systems are widespread and efficient ways of limiting liquidity constraints (Bocquého, G., 2017 D3) 
  • profitability was the main reason for growing these crops (Glithero et al., 2013)  
  • Large initial investment and no income for 2-3 years (Miscanthus), 4-5 years (SRC), (10-20 years) SRF (Martin et al., 2020 D1) 
  • SRF – Poor cash flow (Martin et al., 2020 D1) 
  • Uncertain profitability in comparison to land-uses that are better known (Martin et al., 2020 D1)
  • Many farmers regard SRC willow as a financially risky (Warren et al., 2016 D2) 
  • liquidity constraints hinder adoption (Bocquého, G., 2017 D3) 
  • There are no stable markets for Miscanthus biomass and relevant applications are low-value (Lewandowski, I., J. Clifton-Brown, et al. 2016).

Social 

 

  • Miscanthus- planting and annual harvesting will require supportive contractor and other local employment services. (Martin et al., 2020 D1) 
  • Local economic activity related to employment opportunities. Local employment at conversion plant and associated activities (Thornley, P., 2006.) 

 

  • SRF -Negative publicity regarding the benefits of energy crops (Martin et al., 2020 D1)  
  • SRF- Objections to planning applications for biomass power stations leads to limited feedstock market and demand (Martin et al., 2020 D1) 
  • Attitudes can take longer to change than awareness (Brown et al 2016 D2) 
  • Farmers cited a range of ‘moral’ (e.g. should not be using land for energy crops when there is a shortage of food), land quality, knowledge, profit and current farming practice comments as reasons for not growing DECs (Glithero et al., 2013) 

Technical  

 

  • The energy crop market displays path dependence, arising from the reinforcement of the location of plant construction and energy crop selection, based on the locations of the previous plants and energy crops. Once a plant has been built at a location, and a number of farmers have adopted to produce supply for that plant, that area is more likely to be selected for further plant development, and associated energy crop growth (Alexander et al 2015 D14).  
  • SRC- modern machinery, with high efficiency, working in fields with a larger area, reduces costs significantly (Kwaśniewski et al 2021 D17) 

 

  • SRF-Limited specialist machinery for SRF management (Martin et al., 2020 D1) 
  • need for smaller harvest equipment adapted to small-and-medium-scale area plantations of SRWC (Savoie et al 2013 B) 
  • SRC – technical lack of knowledge (Wolbert-Haverkamp, M. and Musshoff, O., 2014). 

Legal 

 

  • Private long-term production contracts between farmers and biomass processors can act as a risk barrier (Bocquého, G., 2017 D3) 
  • SRF-Irreversible land conversion- Reversion to farming use may not be allowed once SRF is planted as deemed change of use (Martin et al., 2020 D1) 
  • legal conditions? (e.g., cultivation licenses) (Ostwald 2013) 
  • Long-term contracts and legal restrictions may become obstacles in the establishment of SRC (Long-termland contracts, which are essential for establishing SRC plantations, are one of the biggest obstacles for farmers engaging in SRC projects. Consequently, annual payments are an important compensation ) (Fürtner et al 2022 D9) 

Environmental  

 

  • careful allocation of perennial cropping systems into a cropland could produce positive impacts on climate, water, and biodiversity (foster multiple ecosystem services and mitigate ecosystem disservices (Anejionu, O.C. and Woods, J., 2019 D3) 
  • long term weed control (Glithero et al., 2013) 
  • The second-generation bioenergy crop Miscanthus almost always has a smaller environmental footprint than first generation annual bioenergy ones (Hastings et al., 2017). 
  • SRC- Establishment on high organic/peaty soils (upland areas) potentially detrimental to soil carbon levels, soil damage and erosion. (Martin et al., 2020 D1) 
  • SRC-cannot be planted on land with soils that are water-logged (Martin et al., 2020 D1) 
  • Miscanthus-Winterhardiness of Miscanthus is a major constraint (can halt growth, causing diminished achievable yield) (Martin et al., 2020 D1) 
  • Current varieties of Miscanthus are constrained by climate to the south and south east of Scotland (Martin et al., 2020 D1) 
  • Miscanthus- have lower or similar SOC (soil carbon stocks) when compared to grassland controls (Holder et al., 2019 D1) 
  • Direct emissions can occur in the production, transport, handling and processing, while indirect emissions are associated with land use change potentially causing SOC changes (Alexander et al., 2015 D14). 
  • The response to climate change scenarios further favours Miscanthus, suggesting that Miscanthus supply increases under future climate, while SRC willow supply is expected to reduce (Alexander, P., D. Moran, et al. 2014) 
  • large-scale bioenergy production and associated additional demand for irrigation may further intensify existing pressures on water resources (Popp et al 2011) 
  • The reduction of management intensity originating from converting agricultural land use to SRC cultivation results in additional environmental benefits, especially in soil protection and the enhancement of soil life (Schiberna et al., 2021 D9) 

Appendix K: Biomass plants included for proximity analysis

Operator

Site Name

Installed Capacity (MWel)

CHP

Development Status

RWE

Markinch Biomass CHP Plant

65.00

Yes

Operational

E.ON

Stevens Croft

50.40

No

Operational

SIMEC/ Liberty House

Liberty Steel Dalzell

17.00

 

Operational

Norbord (West Fraser)

Cowie Biomass Facility

15.00

No

Operational

EPR Scotland

Westfield Biomass Power Station

12.50

No

Operational

Speyside Renewable Energy Partnership

Speyside Biomass CHP Plant

12.50

Yes

Operational

Scottish Bio-Power

Rothes Bio-Plant

8.30

Yes

Operational

University of St Andrews

Sustainable Power and Research Campus

6.50

Yes

Operational

How to cite this publication: Dowson, F., Leake, A., Harpham, L., Willcocks, J., Peters, E., David, T., Bates, T., Wood, C. (2024). ‘Economic potential of energy crops in Scotland’, ClimateXChange. http://dx.doi.org/10.7488/era/5478

© The University of Edinburgh, 2024
Prepared by Ricardo plc on behalf of ClimateXChange, The University of Edinburgh. All rights reserved.

While every effort is made to ensure the information in this report is accurate, no legal responsibility is accepted for any errors, omissions or misleading statements. The views expressed represent those of the author(s), and do not necessarily represent those of the host institutions or funders.

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info@climatexchange.org.uk

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  1. IEA, 2017 IEA Technology Roadmap: Delivering Sustainable Bioenergy, Unlocking the potential of bioenergy with carbon capture and utilisation or storage (BECCUS) – Analysis – IEA, License: CC 4.0



  2. Land Capability for Agriculture in Scotland | Exploring Scotland | The James Hutton Institute – the study identified the capability classes for agriculture 4.1 to 6.1 and classes for forestry F1 to F5.



  3. Williams et al (for Ricardo), 2023, Report for the Scottish Government: Negative Emissions Technologies (NETS): Feasibility Study: Negative Emissions Technologies (NETS): Feasibility Study – gov.scot (www.gov.scot)



  4. Stakeholder interview





  5. Bioenergy Crops Better For Biodiversity Than Food-Based Agriculture | University of Southampton



  6. Defined as land which was primary forest, designated for nature protection, highly biodiverse grassland (except where harvesting is necessary to maintain grassland status), peatland, continuously forested, wetland in or after 2008.



  7. Based on a meta-analysis of 45 studies on transition to energy crops from ‘marginal’ land.



  8. Definition of marginal land may not be applicable to Scotland.



  9. Gross margin in agricultural costings is typically defined as ‘Output from the enterprise less the Variable Costs, including the allocated variable costs of grass and other forage’



  10. Defined in the Scottish Farm business income survey as “Farms with no enterprise contributing more than two-thirds of their total standard output” – typically including livestock and crops, including animal fodder. An average income



  11. Scottish farm business income: annual estimates 2020-2021 – gov.scot (www.gov.scot) – note that the mixed farming data is an average across farms that meet the definition above.



  12. Scottish Agricultural Census: results – gov.scot (www.gov.scot)



  13. The general cropping, forage category has only one scenario due to the data coming from the Scottish Government Census data which doesn’t provide a low, medium and high scenario and the cost data coming form the Farm Management Handbook 2023/2024



  14. Scottish farm business income: annual estimates 2021-2022 – gov.scot (www.gov.scot)



  15. Gross margin is farm income from a specific production enterprise, e,g, crop or livestock minus costs directly associated with production of that output, but excluding ‘fixed costs’ such as costs associated with farm buildings, general labour and finance costs. Further detail available in: Appendix E Methodology for economic analysis.



  16. The transition of a large land area – scenario 2 – to PECs creates a loss because of the assumptions within our study – we assumed that land which is more economically advantageous for PECs would be converted preferentially, so a larger portion of land transitioned in scenario 1 would make a profit from the transition to PECs, whereas in scenario 2 a large area of land which would make a loss from the transition was included, and so resulted in a total loss on balance.



  17. This study focused mostly on Miscanthus and SRC, but has been used as a best estimate here to give some basis for understanding how potential demand for bioenergy crops could evolve in future to meet Scottish Government NETs ambition.



  18. This refers to the percentage of all Non-LFA Cattle and Sheep land in Scotland – suitable and not suitable for PECs.



  19. Methodology and maps of potential production areas of the three crops produced within the previous project are in Appendix F.



  20. https://www.gov.uk/government/publications/renewable-energy-planning-database-monthly-extract. The database only includes plants generating electricity so large biomass boilers are not captured.



  21. Scottish Emissions Targets – first five-yearly review (theccc.org.uk)



  22. Green growth for Scotland with multi billion pound investment – GOV.UK (www.gov.uk)



  23. These three types of BECCS (Bioenergy with Carbon Capture and Storage) were identified in CCPu, along with BECCS in industry, as potential options for Scotland.



  24. This study focused mostly on Miscanthus and SRC, but has been used as a best estimate here to give some basis for understanding how potential demand for bioenergy crops could evolve in future to meet Scottish Government NETs ambition.



  25. Based on stakeholder comments.



  26. Securing a green recovery on a path to net zero: climate change plan 2018–2032 – update – gov.scot (www.gov.scot)



  27. The-Sixth-Carbon-Budget-The-UKs-path-to-Net-Zero.pdf (theccc.org.uk)



  28. https://www.theccc.org.uk/publication/scottish-emission-targets-progress-in-reducing-emissions-in-scotland-2022-report-to-parliament/



  29. Supporting documents – Negative Emissions Technologies (NETS): Feasibility Study – gov.scot (www.gov.scot)



  30. Update to the Climate Change Plan 2018 – 2032: Securing a Green Recovery on a Path to Net Zero (www.gov.scot) p. 193



  31. Agroforestry is the practice of planting trees, usually to produce a crop of food or wood products, on farmland in combination with arable or livestock farming, often in small patches or strips with fields.



  32. The just transition principles are defined in the Scottish legislation as:


    ‘the importance of taking action to reduce net Scottish emissions of greenhouse gases in a way which:


    a) supports environmentally and socially sustainable jobs,


    b) supports low-carbon investment and infrastructure,


    c) develops and maintains social consensus through engagement with workers, trade unions, communities, non-governmental organisations, representatives of the interests of business and industry and such other persons as the Scottish Ministers consider appropriate,


    d) creates decent, fair and high-value work in a way which does not negatively affect the current workforce and overall economy,


    e) contributes to resource efficient and sustainable economic approaches which help to address inequality and poverty.’



  33. Draft Energy Strategy and Just Transition Plan (www.gov.scot)



  34. A Contract for Difference (CfD) is a private law contract between a low carbon electricity generator and the Low Carbon Contracts Company (LCCC), a government-owned company. Contracts for Difference – GOV.UK (www.gov.uk)



  35. Teagasc- Miscanthus Energy Crop Miscanthus Energy Crop – Teagasc | Agriculture and Food Development Authority



  36. Sustainable Bioenergy Feedstocks Feasibility Study report for the Department for Business, Energy and Industrial Strategy (BEIS) published in 2021



  37. Miscanthus Growers’ Handbook (forestresearch.gov.uk)



  38. Sustainable Bioenergy Feedstocks Feasibility Study report for the Department for Business, Energy and Industrial Strategy (BEIS) published in 2021



  39. Short rotation coppice (SRC) – Crops4energy



  40. Short rotation coppice establishment – Forest research



  41. As above



  42. Feedstocks innovation study task 1 report



  43. https://nora.nerc.ac.uk/id/eprint/512448/1/N512448CR.pdf



  44. Teagasc Miscanthus best practice guidelines Miscanthus_Best_Practice_Guidelines.pdf (teagasc.ie)



  45. Energy crops need support to fulfil potential – Farmers Weekly



  46. DEFRA Area of crops grown for bioenergy in England and the UK Area of crops grown for bioenergy in England and the UK: 2008-2014 – GOV.UK (www.gov.uk)



  47. Forestry sector workforce ‘chronically under-resourced’ | The Scottish Farmer



  48. Forest Research -Short Rotation Forestry Establishment Microsoft Word – TD Project Report FCS SRF DI SRMast v AJH.doc (forestry.gov.scot)



  49. Dependent on size of planting area and location in relation to National Scenic Areas and other sensitive areas – latest guidance available from Forestry Scotland. Scottish Forestry – Environmental Impact Assessments



  50. Hemp Project | The Rowett Institute | The University of Aberdeen (abdn.ac.uk)



  51. Hemp-as-Biomass-Crop-1.pdf (biomassconnect.org)



  52. HEMP-30 catalysing a step change in the production – phase 1 report (publishing.service.gov.uk)



  53. Carbon-busting hemp could help transform Scottish agriculture to zero emissions (theconversation.com)



  54. Agroforestry systems as new strategy for bioenergy — Case example of Czech Republic – ScienceDirect



  55. GDP deflators at market prices, and money GDP March 2023 (Quarterly National Accounts) – GOV.UK (www.gov.uk)



  56. GB fertiliser prices | AHDB



  57. GDP deflators at market prices, and money GDP March 2023 (Quarterly National Accounts) – GOV.UK (www.gov.uk)



  58. Section 2: Plant biomass: Miscanthus, short rotation coppice and straw – GOV.UK (www.gov.uk)



  59. Scottish farm business income: annual estimates 2021-2022 – gov.scot (www.gov.scot)



  60. Scottish Agricultural Census: results – gov.scot (www.gov.scot)



  61. fas.scot/downloads/farm-management-handbook-2022-23/



  62. Source: Scottish Farm Management Handbook 2022-23



  63. Source: Final Results of the June 2021 Agricultural Census: Table 12



  64. Green Book supplementary guidance: discounting – GOV.UK (www.gov.uk)



  65. June Agricultural Census (ruralpayments.org)



  66. The James Hutton Institute, N.D., Land Capability for Agriculture in Scotland. https://www.hutton.ac.uk/sites/default/files/files/soils/lca_leaflet_hutton.pdf



  67. https://www.gov.uk/government/publications/biomass-feedstocks-innovation-programme-successful-projects



  68. https://www.gov.uk/government/publications/biomass-feedstocks-innovation-programme-successful-projects/biomass-feedstocks-innovation-programme-phase-2-successful-projects


The Scottish Government’s Carbon Calculator for wind farms on Scottish peatlands was developed in 2008, to calculate the impact of wind farm development on peatland carbon stocks in Scotland and thereby support decision making. Electricity generation emission factors are updated annually, but no major revisions have been made to the Carbon Calculator since 2014.

Aims

The increased focus on the transition to net zero might affect the suitability of the Carbon Calculator for future use. This research conducted a detailed review of the latest spreadsheet version of the Carbon Calculator (v2.14), which mirrors the web version (v1.8.1). It provides an evidence base for future considerations and recommendations.

This review has initiated further discussions and highlighted the need for ongoing engagement, which will be instrumental in the development of the Carbon Calculator.

Key findings

Based on the findings of a technical assessment, evidence review and quality control mechanisms, the report recommends that when considered against recent policy updates and advancements in science, the Carbon Calculator, in its current form, should be updated. Each area of the Carbon Calculator was assessed for scientific accuracy and data availability:

  • The ‘payback time and CO2 emissions’ are not relevant/consistent with the findings of the technical assessment and literature review. It is important to consider whether emissions due to turbine life and back up are required, given new planning policy and the applicability of whole lifecycle carbon assessments.
  • For all peat-related areas of the Carbon Calculator, as well as the forestry area, accuracy is lacking in one or more methodologies, use of emission factors and assumptions.
  • While some data are accessible to users, it is not clear if they are able to accurately obtain some of that data – in particular, for variables that drive the results (the water table depth and extent of drainage), which could affect the accuracy of outputs.

This study is the first phase of a review of the Carbon Calculator. The findings of the report will be used to inform the next phase.

For further details, please read the report.

If you require the report in an alternative format, such as a Word document, please contact info@climatexchange.org.uk or 0131 651 4783.

Research completed: July 2024

DOI: http://dx.doi.org/10.7488/era/5506

Executive summary

The Scottish Government’s Carbon Calculator for wind farms on Scottish peatlands was developed in 2008, to calculate the impact of wind farm development on peatland carbon stocks in Scotland and thereby support decision making. Electricity generation emission factors are updated annually, but no major revisions have been made to the Carbon Calculator since 2014.

Aims

The increased focus on the transition to net zero might affect the suitability of the Carbon Calculator for future use. This research conducted a detailed review of the latest spreadsheet version of the Carbon Calculator (v2.14), which mirrors the web version (v1.8.1). It provides an evidence base for future considerations and recommendations.

This review has initiated further discussions and highlighted the need for ongoing engagement, which will be instrumental in the development of the Carbon Calculator.

Key findings

Based on the findings of a technical assessment, evidence review and quality control mechanisms, we recommend that when considered against recent policy updates and advancements in science, the Carbon Calculator, in its current form, should be updated. Each area of the Carbon Calculator was assessed for scientific accuracy and data availability:

  • The ‘payback time and CO2 emissions’ are not relevant/consistent with the findings of the technical assessment and literature review. It is important to consider whether emissions due to turbine life and back up are required, given new planning policy and the applicability of whole lifecycle carbon assessments.
  • For all peat-related areas of the Carbon Calculator, as well as the forestry area, accuracy is lacking in one or more methodologies, use of emission factors and assumptions.
  • While some data are accessible to users, it is not clear if they are able to accurately obtain some of that data – in particular, for variables that drive the results (the water table depth and extent of drainage), which could affect the accuracy of outputs.

In addition to the technical assessment, the research has triggered the need to examine the wider planning and consenting context through the following questions:

Does the calculator need to consider the lifecycle emissions of the wind farm, or could the focus be purely on the impact of development on peat?

Well established methods and tools are available to undertake Whole Life Carbon Assessments (e.g. PAS2080), including forthcoming offshore wind carbon footprinting guidance. This aspect of the Carbon Calculator might not be necessary as it replicates these approaches. Instead, it may be more beneficial to concentrate efforts on analysing the specific impacts of development on peatlands/habitat carbon emissions.

Is the output of the Carbon Calculator useful as a decision-making tool?

Since the inception of the Carbon Calculator, it has become clearer that improving and restoring biodiversity is important to tackling climate change. This progress is reflected the National Planning Framework 4’s mitigation hierarchy.

As the UK transitions to net zero, the current ‘carbon payback’ approach becomes less relevant, as it compares development emissions to the counterfactual of electricity generated by fossil fuels. The focus should shift to evaluating the impact of the developments on the natural environment, specifically, whether it improves the environment and sequesters CO2 effectively.

To better assess the development’s impact on peatland carbon emissions, the timeline for achieving ‘carbon payback’ or ‘carbon neutrality’ should consider land-based emissions. For example, ‘payback time’ could be defined as the period needed to restore peatland to a ‘near pristine’ condition from a reported baseline, compared to the site’s baseline emissions without development and counterfactual scenarios for non-peaty sites, and Scotland’s widespread peatland restoration efforts.

Should the Carbon Calculator incorporate other land use types?

This would offer a more comprehensive view of the carbon impact on other land use types, as compared to the carbon impact on peatland. This aspect should be evaluated considering Scotland’s evolving biodiversity net gain requirements, current Peatland Management Plans (PMP), Habitat Management Plans (HMP), and their anticipated updates.

Are the quality controls sufficient?

There are no in-built quality control mechanisms within the Carbon Calculator. Due to its complexity and skillsets required to review the data outputs, the Carbon Calculator is not used as a decision-making tool in the capacity it is intended. Additional quality controls would be beneficial.

The future of the Carbon Calculator

In addition to the technical review, the report also considers the future of the Carbon Calculator in terms of a review of incorporating high-resolution spatial data (HRSD) and/or peatland condition categories (from the Peatland Carbon Code), and applicability of the Carbon Calculator to other developments.

Integrating HRSD into the Carbon Calculator would enable an understanding of land cover types, providing proxies for peat condition and water table depth. This could reduce the need for manual site surveying for data collection and enable wider evaluation of the site.

We recommend that the integration of HRSD is explored for future versions of the Carbon Calculator, to ascertain the level of accuracy these enhancements could bring (i.e. through reduced manual inputs and/or quality controls). This can be done in conjunction with the findings from Scottish Government’s exploration of a national LiDAR mapping scheme.

The Peatland Code’s emission calculator provides emission factors to calculate the average net emissions from peatland in various conditions, based on the UK inventory. Whilst not Scotland-specific, integration of the peatland condition categories could provide a recognised approach to quantifying the benefits of peatland restoration activities.

There is potential for the Carbon Calculator to be adapted and applied to grid infrastructure and other development types on peatland and carbon rich soils, even though it is currently employed solely for wind farm developments. There are no concerns on the Carbon Calculator’s ability to be used on projects of all sizes. However, to be applied to different infrastructure types, consideration would need to be given to their unique spatial aspects, e.g. the effects of shading and effect of excess heat for solar farms. Further research is needed to understand the implications of other infrastructure developments on peatland and carbon rich soils prior to extending the applicability of the Carbon Calculator.

Glossary / Abbreviations

Baseline

Current baseline represents existing GHG emissions from the project boundary site prior to construction and operation of the project under consideration (IEMA, 2022).

Carbon-rich soils

Organo-mineral and peat soils are known as carbon-rich soils. A peat soil is defined in Scotland as when soil has an organic layer at the surface which is at least 50cm deep. Organo-mineral soil or peaty soil is soil which has an organic layer at the surface less than 50cm thick and overlies mineral layers (e.g. sand, silt and clay particles). There is also a relatively rare group of soils in Scotland known as humose soils. These have organic rich layers with between 15 and 35% organic matter. These are mineral soils but also considered to be carbon rich.

Dissolved Organic Carbon

fraction of organic carbon that can pass through a filter with a pore size between 0.22 and 0.7 micrometres.

High-Resolution Spatial Data

High-resolution spatial data refers to detailed information about the Earth’s surface captured with exceptional precision by satellite imagery.

Life Cycle Assessment

A Life Cycle Assessment (LCA) is a methodology for assessing environmental impacts associated with all the stages of the life cycle of a commercial product, process, or service.

PAS 2080

PAS 2080 is a globally applicable standard for managing carbon in infrastructure. The standard looks at the whole value chain of a project and aims to reduce carbon and cost through design, construction, and use.

Particulate Organic Carbon

fraction of organic carbon that can’t pass through a filter with a pore size between 0.22 and 0.7 micrometres.

Payback period

Payback period is used within the Carbon Calculator to estimate the time it will take for a wind farm to ‘offset’ the greenhouse gases emitted. I.e., the displacement of the carbon ‘costs’ of construction with the carbon ‘savings’ due to the displacement of grid-based electricity generation from non-renewable sources.

Peat

Peat is organic material formed when dead plant material collects in cool, waterlogged conditions where there is very little oxygen, it breaks down slowly forming a layer of mainly organic matter.

Peat soil

(organic soil) in Scotland is defined as soil with a surface peat layer with more than 60% organic matter and of at least 50cm thickness.

Peaty soils

(organo-mineral soil) have a shallower peat layer at the surface less than 50cm thickness over mineral layers.

Peatland

Under NPF4, peatland is defined by the presence of peat soil or peaty soil types. This means that “peat-forming” vegetation is growing and actively forming peat, or it has been grown and formed peat at some point in the past. Peatlands can include blanket bog, upland raised bog, lowland raised bog and fens.

Peatland Code

The Peatland Code is a voluntary certification standard in the UK and is designed for peatland restoration projects aiming to market the climate benefits of restoration. The Peatland Code ensures that restoration projects are credible and deliverable, providing assurances to carbon market buyers.

The Peatland Code defines ‘peatland’ as ‘areas of land with a naturally accumulated layer of peat, formed from carbon-rich dead and decaying plant material under waterlogged conditions’.

Peat Management Plan

A peat management plan (PMP) is an operational plan in development projects on peat, describing baseline peat conditions, detail on excavation and reuse volumes, classification of the excavated material, how the excavated peat will be handled, stored, reinstated or other use or disposal.

Peatland Restoration

Carrying out an intervention which in combination with natural processes improves the hydrological function and coverage and good condition of priority peatland habitat vegetation, aiming to result in a peatland that is actively forming peat and sequestering carbon. Further detail will be stated in the Peatland Standard (under preparation).

Priority Peatland Habitat

Peatland National Vegetation Classification communities noted as a Priority Peatland Habitat are: M1, M2, M3, M15, M17, M18, M19, M20 and M25, together with their intermediates. These have been recognised under the Scottish Biodiversity Framework as being important to protect for their conservation and biodiversity value.

Scottish Environment Protection Agency

The Scottish Environment Protection Agency is Scotland’s principal environmental regulator, its main role is to protect and improve Scotland’s environment.

Whole life carbon

Assessment of emissions associated with an asset over its entire life; encompassing its development, operation, and end-of-life.

CH4

Methane

CO2

Carbon Dioxide

DOC

Dissolved organic carbon

ECU

Energy Consents Unit

EIA

Environmental Impact Assessment

ESA

European Space Agency

GHG

Greenhouse Gas

GIS

Geographic Information Systems

HRSD

High-Resolution Spatial Data

IPCC

Intergovernmental Panel on Climate Change

JHI

James Hutton Institute

kWh

Kilowatt-Hour

LCA

Life Cycle Assessment

LiDAR

Light Detection and Ranging airborne mapping technique

MW

Megawatt

MWh

Megawatt-Hour

NASA

National Aeronautics and Space Administration

NPF4

National Planning Framework 4

N2O

Nitrous Oxide

PEAG

Scottish Government’s Peatland Expert Advisory Group

PMP

Peat Management Plan

POC

Particulate Organic Carbon

SAR

Synthetic Aperture Radar

SEPA

Scottish Environment Protection Agency

IUCN

International Union for Conservation of Nature

WLCA

Whole lifecycle carbon assessment

Introduction

Background

The Scottish Government’s Carbon Calculator for wind farms on Scottish peatlands (hereafter referred to as ‘the Carbon Calculator’) was developed in 2008 and updated in 2011 and 2014. It was developed due to concerns raised about the reliability of methods used to calculate the time taken for these facilities to reduce greenhouse gas emissions, combined with an increasing public policy demand for renewable energy following Scotland’s commitments at the time to reduce greenhouse gas emissions by reducing the use of fossil fuels for energy generation, principally; Scottish Planning Policy 6: Renewable Energy to deliver renewable energy in a way that “affords appropriate protection to the natural and historic environment without unreasonably restricting the potential for renewable energy development” (Scottish Government, 2007).

The Carbon Calculator was developed to ‘support the process of determining wind farm developments in Scotland. The tool’s purpose is to assess, in a comprehensive and consistent way, the carbon impact of wind farm developments. This is done by comparing the carbon costs of wind farm developments with the carbon savings attributable to the wind farm.’ (Nayak et al, 2008). The output of the Carbon Calculator compares the carbon costs of a wind farm development with the carbon savings attributable to the production of renewable energy (when compared to a counterfactual alternative). Electricity generation emission factors are updated annually, but no major revisions have been made to the Carbon Calculator since 2014.

The Scottish Environment Protection Agency (SEPA) developed the Carbon Calculator into a web Carbon Calculator (C-CalcWebV1.0), which has been available since 2016. The calculator is currently owned by the Scottish Government and is hosted and maintained by SEPA. The Carbon Calculator is currently used by developers to submit project carbon assessments. These submissions are then evaluated by the Energy Consents Unit (ECU) as part of the application for consent.

An evolving legislative, policy, science, and technology landscape

In the 16 years since the Carbon Calculator’s inception, there has been an increased focus on the transition to net zero, with updates to Scottish legislation and policy reflecting this shift. Key legislation and policy drivers include:

  • The Climate Change (Emissions Reduction Targets) (Scotland) Act 2019 (updated): sets a key driver for Scotland to deliver and meet its carbon reduction targets.
  • Scotland’s National Planning Framework 4 (NPF4) (adopted in February 2023): sets the framework for development across Scotland, including renewable energy. NPF4 includes national planning policies which set out ‘to protect carbon-rich soils, restore peatlands and minimise disturbance to soils from development’. Policy 5 sets out a mitigation hierarchy[1], and new development proposals on peatlands, carbon-rich soils, and priority peatland habitat are only supported in certain limited circumstances, including renewable energy generation. The policy also outlines the need for a site-specific assessment (such assessments may include peat depth surveys, Peat Landslide Hazard Risk Assessment, and detailed habitat and condition surveys) to identify the likely net effects of the development on climate emissions and loss of carbon. The mitigation hierarchy can be achieved through the Construction Environmental Management Plan, Habitat Management Plan (HMP), and Peat Management Plan (PMP), developed at the application stage.

There have also been significant advancements in science and technology during this period. The collective understanding of peatland science has evolved, and research, technology, and collaborative groups have fostered a greater understanding of the science, with the likes of the Peatland Code and NatureScot National Peatland Plan emerging as a result. This new legislative, policy and science landscape highlight the need for a comprehensive review of the Carbon Calculator’s original design and purpose.

Aim of the report

This report provides the findings of a technical assessment of the latest spreadsheet version of the Carbon Calculator (v2.14), which mirrors the web-version (v1.8.1) to determine if in its current form it remains fit for purpose, considering recent policy updates, the ongoing transition to net zero, and advancements in science. Furthermore, the report provides an evidence base for future considerations and explores how the Carbon Calculator could be improved via Peatland Code category integration, use of High-Resolution Spatial Data (HRSD), and improved quality controls.

Carbon Calculator Technical Assessment

Overview

The Carbon Calculator features numerous components used to assess the carbon impact of wind farm developments on Scottish peatland. The Carbon Calculator is split into the areas shown in Table 1. Appendix 11.3 provides a detailed breakdown of each section, including their specific calculations and assumptions.

Table 1: Carbon Calculator Section

Areas of the Carbon Calculator

Report Section

Data inputs

3.2

The core input data, forestry input data, and construction input data tabs are used by the user to insert key variables into the Carbon Calculator, to inform the development’s estimated payback time and CO2 emissions.

 

Payback time and CO2 emissions

3.3

Collates the results from each area of the Carbon Calculator and presents the carbon payback period and carbon intensity per kWh electricity generated.

 

Wind farm CO2 emission savings

3.4

Savings are calculated against the electricity generated by coal, a fossil-fuel mix, and the UK average grid mix, multiplied by the wind farm’s lifetime electricity generation at the time of the development’s application.

 

Emissions due to turbine life

3.5

Emissions associated with turbine life (manufacturing, construction, and decommissioning) are presented based on user input or estimated based on installed capacity. Emissions associated with foundations (concrete) are calculated separately.

 

Loss of carbon due to back up power generation

3.6

Emissions associated with back up requirements are calculated against the electricity generated by coal, a fossil-fuel mix, and the UK average grid mix, multiplied by the wind farm’s lifetime electricity generation.

 

Loss of carbon fixing potential of peatlands

3.7

Quantification of the annual carbon sequestration from bog plant fixation (without the wind farm) and thereby the loss as a result of development.

 

Loss of soil CO2

3.8

Emissions associated with loss of soil organic carbon from the peat removed and peat drained.

 

CO2 loss by DOC and POC loss

3.9

CO2 losses from dissolved organic carbon (DOC) and particulate organic carbon (POC) within waters in drained land that has been restored.

 

Loss of carbon due to forestry loss

3.10

Loss of future carbon sequestration associated with forest felling as part of the wind farm development.

 

Carbon saving due to improvement of peatland habitat

3.11

Estimates the reduction in GHG emissions due to restoration following the end of the wind farm’s lifespan.

 

 

The assessment provides a review of each area of the Carbon Calculator as outlined in Table 1. Each section consists of the following:

  • Assessment findings – narrative summarising the findings from the technical assessment and evidence review. For the technical areas of the Carbon Calculator a Red, Amber, Green (RAG) rating has been provided to illustrate the technical accuracy and data availability of each area. It uses the colour rating system presented in Table 2.
  • Key considerations and questions – considers the key takeaways from the assessment, and outlines questions for policy decision makers when considering revisions to the current Carbon Calculator.

Table 2. RAG Ratings

RAG

Criteria: Scientific accuracy

Criteria: Usability

White

Not applicable (rationale explained within narrative).

Green

The methodologies, use of emissions factors and assumptions are relevant and consistent with best practice.

Data is site/project specific, is available to the Carbon Calculator user, and supports an accurate outcome.

Amber

Accuracy is lacking in one or more methodologies, use of emissions factors and assumptions.

There is some uncertainty around the data availability.

Red

The methodologies, use of emissions factors and assumptions are not relevant/consistent with findings of the literature review.

Data is not site specific/ is inaccessible/unavailable to the user.

Assessment findings: Data inputs

Scientific accuracy

The scientific accuracy of the data inputs is provided as part of the narrative within the assessment findings for the corresponding technical areas of the Carbon Calculator (Sections 3.3-3.11). Therefore, no RAG rating has been provided.

Usability

The following commentary applies to the Carbon Calculator’s core input data. Specific commentary relating to data inputs of the technical areas of the Carbon Calculator are covered within the corresponding sections of this report (Sections 3.3-3.11).

  • The user is required to input a high number of variables (i.e. for the core input data, 70 input variables are required).
  • Each input variable requires an expected value, as well as a minimum and maximum range, therefore over ~200 input variables are required in total for core inputs.
  • For infrastructure design related inputs (wind farm characteristics, borrow pits, foundations, access tracks, cable trenches and peat excavated) the values are well defined based on the wind farm design, therefore the minimum and maximum ranges could represent unnecessary data requirements for design related inputs given their level of certainty. If still viewed as necessary in some instances, a minimum and maximum range could be automated, and/or an optional requirement for users.

Key consideration: Minimum and maximum data inputs

Wind farm characteristics – consider removal/option to ‘opt out’ of minimum and maximum variables where site specific data is known and can be evidenced by the user.

Peat variables – Review the minimum and maximum parameters for peat variables and explore replacing with individual infrastructure specific inputs (i.e. Turbine 1, 2 etc). Industry feedback indicated that prior to completing the Carbon Calculator, users proactively aim to reduce the impact of development on peat through the design process. If there is large variation in peat parameters around the site, should more detailed site-specific data be captured (to reflect the construction and forestry ‘areas’, and/or align with the PMP reporting where individual infrastructure outputs are provided) as an alternative?

Assessment findings: Payback time and CO2 emissions

Scientific accuracy

  • Although the calculations that produce the payback time and CO2 emissions are accurate (i.e. there are no errors in them), the carbon payback time that is generated (measured against the current fossil-mix of electricity generation) is a significant simplification which does not present an accurate representation of future payback. This is because the payback calculations assume a consistent counterfactual for the lifetime of the wind farm. However, as we transition to net zero, the National Grid is rapidly decarbonising and forecast to be near net zero by 2035 (DESNZ, 2023).

Usability

  • Payback combines infrastructure emissions (embodied carbon from wind turbines and their construction) with site-specific factors associated with peatland disturbance, and/or management. Emissions from the wind turbine manufacturing make up the largest proportion of the emissions, and so in this context, the overall carbon impact on peat (i.e. all peat related carbon calculations) appears to the user as a small proportion.
  • Currently there are no official guidelines about what constitutes an acceptable or unacceptable payback time, which would benefit both users and decision makers in determining ‘what good looks like’ for land based emissions.

Key consideration: Is the output of the Carbon Calculator useful as a decision-making tool?

As the National Grid transitions to net zero, the presented ‘savings’ (comparison to fossil generated electricity) become less relevant. It may be more appropriate to consider the ‘payback time’ as the time taken to restore the peatland condition to ‘near pristine’ from a reported baseline. To inform this, the sources of emissions could be split out and reported separately:

  • Emissions resulting from land use change (the impact on land carbon emissions as a result of the development including all peatland and other carbon rich soil related carbon sources), should be compared against the project site’s baseline emissions.
  • Emissions associated with the construction, operation, and decommissioning (Whole Lifecycle Carbon Assessment (WLCA)) of the wind farm. To aid decision making, this should be benchmarked against industry best practice, and/or compared against the whole life carbon impact of the counterfactual (e.g. gas turbine plant). Although this may be included within a WLCA, in which case this function is not required.
  • The carbon intensity of electricity generated could primarily be compared against i) the current back-up energy source of natural gas and ii) against the UK average (considering future decarbonisation) if not done so via a WLCA.

Key consideration: Is the focus of the Carbon Calculator correct?

Currently, the main use within decision making is the payback period. However, this is based on the counterfactual of electricity generated by fossil fuels. Focusing on land-based emissions and the impact of development on peatland, an alternative would be to consider the baseline site conditions and ‘payback’ time to a restored site (see 3.3.3 for suggested approach). There is widespread action to restore degraded peatland across Scotland (Scottish Government, 2024), it could be expected that if a wind farm is not developed, the sites would be restored through a variety of financial mechanisms such as the Peatland Code, and Scottish Government funding (ibid). Another relevant counterfactual could include the land-based emissions from a non-peaty site. Whether a counterfactual payback period should be updated to reflect this context is an important consideration.

Key consideration: Does the Carbon Calculator need to consider the lifecycle emissions of the wind farm, or could the focus be purely on the impact of development on peat and other carbon rich soils?

In order to demonstrate a minimisation of emissions, established methods and tools are available to undertake WLCA (e.g. PAS2080), which will include materials, construction, operational and decommissioning emissions of the entire wind farm. NPF4 Policy 2 (climate mitigation and adaptation) states that all proposals will be ‘be sited and designed to minimise lifecycle greenhouse gas emissions as far as possible.’ Given the new policy context in combination with the Carbon Calculator’s core aim (to determine the impact of development on peatland carbon emissions), key considerations include:

  • Whether the lifecycle emissions of a wind farm need to be included in the Carbon Calculator?
  • Could the calculations in the Carbon Calculator solely be focused on the impact of the development on peatland emissions?
  • Is the presentation of the current payback output necessary or appropriate for decision making?

Assessment findings: Wind farm CO2 emission savings

Scientific accuracy

  • The UK grid average is forecast to be broadly decarbonised by 2035 (BEIS, 2020). Using the current grid average (DESNZ, 2023) across the lifetime of the wind farm project represents a ‘static’ coefficient which is not representative of long-term UK grid decarbonisation over time. Additionally, over time as the grid average decarbonises this comparison will not show an operational benefit of using renewable energy.
  • The UK generates ca. 1% of electricity from coal (Statista, 2024). The emissions factors in the Carbon Calculator are updated annually. If users apply the current (optional) coal factor, this factor is also a ‘static’ coefficient. Coal is due to be phased out completely by the end of September 2024 (BEIS, 2021), and therefore the ‘coal-fired electricity generation’ comparison should be removed as it is not a representative comparison.
  • Renewable energy from wind and solar is not guaranteed and therefore a backup is required. Currently, where back up for renewables is required, gas peaking plants provide additional capacity. As we transition to a zero-carbon grid, natural gas will continue to be used to support both renewable back-up and additional demand (BEIS, 2020). There is also work ongoing nationally (Great Grid Upgrade, (National Grid, 2024)) to improve infrastructure and connectivity which will reduce the reliance on back-up energy requirements.
  • Most of Scotland’s electricity demand is already met by renewables (Scottish Government, 2024). There is an opportunity to increase renewables across the UK and for exports, however, this will require appropriate infrastructure.
  • The counterfactual emission factors only include electricity generation (i.e. the emissions associated with burning fossil fuels to generate electricity). They exclude the development of the infrastructure (i.e. the power station). Therefore, savings are based on operational energy efficiency, there is no consideration to the embodied carbon or operational maintenance of the alternative power.
  • Noting the transition to net zero, consideration needs to be given to the appropriateness of represented savings.

Usability

  • This section of the Carbon Calculator is used to calculate the Wind farm CO2 emissions. The input variables which inform it are acceptable in terms of usability.

See Section 3.3.4 Key consideration: Is the focus of the Carbon Calculator correct?

 

Assessment findings: Emissions due to turbine life

Scientific accuracy

  • The methodology for estimating emissions is based on turbine capacity derived from the regression analysis of data points found within a selection of papers dated between 2002 and 2006. The wind industry has evolved in the last 20 years and these assumptions are outdated, for the following reasons:
  • The average onshore wind turbine has increased over recent years to 2.5-3MW (National Grid, n.d.). the references within the current Carbon Calculator are based on studies around 1MW (Lenzen and Munksgaard, 2002; Ardente et al., 2006; Vestas, 2005) and have a direct correlation between turbine MW and embodied carbon (i.e. the greater the power, the higher the embodied carbon), however due to technology advancements (i.e. lightweighting), increased power may not require increased materials. The methodology should be updated to consider more recent manufacturer lifecycle assessments.
  • The physical size of UK wind turbines (i.e. height and turbine span) have increased.
  • The Carbon Calculator uses an emissions factor for reinforced concrete taken from The Concrete Centre (2013). This reference has been superseded with the most recent market data being available for 2023 (Concrete Centre, 2023) and should be updated.
  • Estimations only account for lifetime emissions attributed to turbine structures and concrete hard standings. The methodology disregards emissions from the manufacture, construction, and disassembly of other wind farm assets (e.g., site fences, access tracks, battery storage, etc) (Appendix 10.1). Carbon emissions resulting from the transport of labour and materials to the construction-site is also excluded. This underestimates emissions and does not align to common WLCA practice (e.g., PAS 2080).
  • Emissions exclude decommissioning; due to the uncertainty in this area this would be difficult to estimate, however it should be recognised that decommissioning activities would result in additional disruption to peat. With the net zero transition and increasing energy demand it is likely that sites will be repowered rather than decommissioned. However, as wind farm developments are only provided with consent to operate for fixed period (and should be followed by decommissioning), it may not be appropriate to include this functionality.

Usability

  • Many lifecycle assessments for wind turbines include foundations (e.g. Vesta, n.d.). Therefore the ‘carbon dioxide emissions from turbine life’ variable may result in double counting of construction emissions when using the ‘direct input of total emissions’ option if not split out by the turbine provider and/or Carbon Calculator user, when paired with foundations and hardstanding emissions, and/or the construction input data tab.
  • As this is a significant part of the assessment, lifecycle emissions should be modelled on site specific data.
  • Depending on the size of the development, developers may be required to submit an Environmental Impact Assessment (EIA), including a WLCA. Scottish Government is preparing Planning and Climate Change guidance, which includes consideration of information sources, tools, methods and approaches (including WLCAs) that can be used to demonstrate whether and how lifecycle greenhouse gas emissions of development proposals have been minimised. For reference, there is currently an industry standard approach for wind farm LCA being developed for offshore wind developments through the Offshore Wind Sustainability JIP (anticipated to be released by the end of 2024) (The Carbon Trust, 2022).

See Section 3.3.4 Key consideration: Is the focus of the Carbon Calculator correct?

See Section 3.3.5 Key consideration: Does the Carbon Calculator need to consider the lifecycle emissions of the wind farm, or could the focus be purely on the impact of development on peat?

Assessment findings: Emissions due to back up power generation

Scientific accuracy

  • Back up requirements are typically modelled using the guidance note assumption of 5% of the wind farm capacity following guidance within the Carbon Calculator (Dales et al, 2004). The wind industry has evolved in the last 20 years. From a review of literature and current policy, there are no specific requirements for back-up in planning applications for renewable energy. As the National Grid decarbonises (DESNZ, 2023) back-up will increasing be supplied by other renewable energy. Therefore, this area of the Carbon Calculator could be redundant.
  • Emissions associated with back up are calculated based on a grid connection. See Section 3.4 regarding selection of counterfactual emission factors. There are other options such as interconnections, energy storage solutions and nuclear that provide alternatives (National Grid, 2024).

Usability

  • The input variable is acceptable in terms of usability.

Key consideration: Should the Carbon Calculator include ‘Back-up requirements’?

From a review of literature and current policy, there are no specific requirements for back-up in planning applications for renewable energy, As the National Grid decarbonises (DESNZ, 2023) back-up will increasing be supplied by other renewable energy. Where back-up requirements are specified, it’s anticipated that these would be included within an WLCA. Therefore, this area of the Carbon Calculator could be redundant.

Assessment findings: Loss of CO2 fixing potential

Scientific accuracy

  • This section of the Carbon Calculator quantifies the annual carbon sequestration from bog plant fixation (without the wind farm). The loss of carbon fixing potential is calculated from user inputs for the area which peat is removed (m2) as well as the area affected due to drainage (m2). Loss of CO2 fixing potential has a low significance within the outputs of the Carbon Calculator (typically 1-2% of the total lifetime emissions), most land-based CO2 losses due to wind farm development are associated with soil organic matter (see Appendix 11.3).
  • Loss of carbon fixation is calculated based on the lifetime of the wind farm and time required until full peatland functioning is restored. No consideration is given to the condition the peatland will be restored to.
  • The Carbon Calculator currently assumes that peatland is in a pristine condition and therefore is a net carbon sink. However, 80% of UK peatland is already degraded (NatureScot, 2015). Degraded peatland is likely to be a net source of emissions rather than a sink (NatureScot, 2015).
  • The Carbon Calculator assumes a constant rate of carbon fixation over time, failing to take account for the impact of changing climatic conditions e.g. increased frequency of drought. See key consideration 3.7.4 on the impacts of climate change.
  • The condition of the peatland is influenced by vegetation composition (Marshall et al, 2021), and degraded peat is associated with changes to vegetation structure with scrubbier species to the disadvantage of characteristic peatland species (NatureScot, n.d.). Literature was located which described the known link between ecosystem resilience and peatland vegetation (Speranskaya et al, 2024), and highlighted that the interactions between temperature, precipitation, nitrogen deposition, and atmospheric CO2 and their effects can be a result of vegetation composition (Heijmans et al, 2008).
  • The literature review indicates that the Carbon Calculator’s current output for ‘loss of carbon fixation potential’ may not be accurate, because: i) the current condition of peatland may not be pristine, and may therefore have a lower carbon fixation rate, and ii) there is considerable uncertainty in the ability to restore peatland to its fully functioning ‘pristine’ state so the future fixation rate may be overestimated.
  • However, no research was located which presented the relationship between peatland condition and bog fixing potential, or updated fixation emission factor rates. This is anticipated to be because other methodologies (e.g. Evans et al, 2023) do not explicitly assess the loss of bog fixing potential, but instead assess the ‘Net Ecosystem Production of the peatland’. There was also no literature located to explain how the interaction between vegetation and hydrology impacts carbon fixing potential, and so the degree to which peatland condition impacts the carbon fixation value in the Carbon Calculator is uncertain and represents an evidence gap.
  • This review is unable to conclusively determine the accuracy of this area of the Carbon Calculator and whether carbon fixation is accurately represented. Although carbon fixation represents a very small proportion of the total emissions, the current assumption is likely to represent a worst case (in terms of emissions) and may be suitable in the absence of other literature to inform it. This area of the Carbon Calculator could be superseded through the integration of the Peatland Code which uses the UK inventory and includes carbon sequestration (e.g. carbon fixation from bog plants) within its net emission factors.

Usability

  • Carbon fixed by bog plants is a user input (a guidance note within the Carbon Calculator states ‘the Scottish National Heritage use a value of 0.25tC/ha/yr.’ however the guidance which informs this is no longer available, and this is highlighted as an evidence gap.

Key consideration: Should the baseline condition of peatland be incorporated in the Carbon Calculator?

Whilst the loss of CO2 fixing potential will remain the same, degraded peatland is likely to be a net source of emissions rather than a sink (ibid) and there is no consideration of these emissions within the Carbon Calculator. Other reasons for incorporating the baseline condition and replication of the Peatland Code’s calculation methodology are provided within this report (see Section 3.11.1). The use of HRSD could support the identification of peatland condition.

Key consideration: Impacts of climate change

Carbon fixing potential of blanket bogs (which make up 90% of Scotland’s peatland) is anticipated to decline/be under threat by 2050-80 when considering the impact of climate change (Ferretto et al, 2019). The impact of climate change on peat has not previously been considered, however is of growing concern. Degraded peatlands are less resilient to the impacts of climate change, so the emissions will change proportionally more in degraded versus pristine peatland. Climate change is also likely to make successful restoration more challenging Norby et al (2019), although it has also been indicated that successful restoration of degraded/actively eroded sites could see the greatest CO2 improvements (Evans et al, 2023), there is variation in results of the impacts of climate change on carbon fluxes following restoration (see Section 3.11 for more information).

Assessment findings: Loss of soil CO2

Scientific accuracy: Peat removed

  • Calculating volume of peat removed:
  • The Carbon Calculator uses an appropriate methodology for calculating the volume of peat removed for borrow pits, turbine foundations, hard-standing and access tracks, as well as any additional peat.
  • However, the use of averages may be producing a less accurate result than if actual numbers for each infrastructure feature (i.e. turbine foundation #1,2,3 etc) were inputted, as carried out in PMPs. This was reflected in industry feedback where it was highlighted that excavation volumes shown in the PMP are more realistic than what is shown in the Carbon Calculator.
  • Calculating CO2 loss from removed peat:
  • This is the largest source of peatland related carbon emissions because of development.
  • The carbon content of dry peat and dry soil bulk density are important parameters which drive the outputs of the Carbon Calculator. Sensitivity analysis (Appendix 10.2) demonstrates the correlation between carbon content of dry peat and dry soil bulk density and carbon losses from soil organic matter. Halving the data input values of either independent variable has the impact of a 60% reduction on emissions associated with carbon losses from soil organic matter.
  • Literature review findings indicate that carbon content of dry peat has a typical range of 50% to 55% and dry soil bulk density a range of 0.06 to 0.25 gcm3 (e.g., Chapman et al., 2009; Ratcliffe et al., 2018; Heinemeyer et al., 2018; Howson, 2021, Lindsay, 2010; Parry and Charman, 2013; Levy and Gray, 2015; Carless et al., 2021; Howson et al., 2022).
  • The calculation methodology is appropriate.
  • The Carbon Calculator assumes a worse-case scenario that all peat removed is destroyed and the carbon content is lost. Although in practice peat is often relocated, which should be more favourable, subject to it being sensitively relocated (SEPA, 2012; IUCN, 2023), there is an evidence gap in literature which illustrates successful peat relocation (i.e. via emissions rates from relocated excavated peat). In the absence of evidence, the assumption that the carbon content will be lost over time is an appropriate worst-case conclusion.

Usability: (Peat removed)

  • Calculating volume of peat removed:
  • The ‘average depth of peat at site’ input variable in the ‘characteristics of peatland before wind farm development’ is not applied to any of the calculations in the Carbon Calculator. However, the ‘average depth of peat removed’ from each development feature (i.e. ‘average depth of peat removed from borrow pit, hard standing, turbine foundations’) is applied to calculate the quantity of peat removed. This provides greater accuracy than the singular ‘average depth of peat at site’ variable which could be removed from the Carbon Calculator.
  • Mirroring the assessment findings from 3.8.1, the data inputs for peat depth provide an average peat depth for each development feature type (e.g. ‘average depth of peat removed from turbine foundations’) they are not specific to each individual feature on which the average is may up of. For example, there will be multiple turbine foundations. The use of an average in this context may be a poor representation of the spatial variability in peat cover, as well as the positioning of infrastructure within that peat cover. This is particularly relevant where there are different peat conditions, depths and land use types across a site. Peat depth is not uniform and varies over short distances due to the underlying topography (Parry et al., 2014). Under blanket peat thickness is typically 0.4–6 m; it can be up to ten metres and often more in raised bogs, and in fens is 0.4–5m. Peat soil is defined as requiring a depth of 0.5m and a surface peat layer containing more that 60% organic matter (NatureScot, 2023). A more detailed data input, like the ‘construction and forestry input data’ sheets and/or reflecting how peat is reported in the PMP (i.e. by turbine, borrow pit etc.) could allow for a more accurate assessment of the quantity of peat removed.
  • NPF4 requires consideration of peaty soils, peat soil and peatland. Whilst the Carbon Calculator can be used in its current form on any peatland and responds appropriately to shallow peat depths (inputted as averages for each infrastructure type) a more specific data input for peat depth from each area where peat is removed would allow for better differentiation between different depths.
  • Calculating CO2 loss from removed peat:
  • Carbon content of dry peat and dry soil bulk density are user inputs. Whilst the exact metrics will be site specific, industry feedback indicated that these data inputs were difficult to obtain due to the lab analysis requirements (to obtain accurate data peat samples requiring drying out for long periods of time) and are therefore often based on assumptions, with one user utilising the von post scale. The ranges identified from the literature review could be incorporated into the Carbon Calculator as recognised minimum and maximum parameters to inform an inbuilt quality control measure.

Key consideration: replace the use of averages with infrastructure specific inputs

This approach would provide more accurate outputs and replicate how peat is reported in the PMP.

Key consideration: Reuse of removed peat

Feedback from industry indicated that where possible projects seek to relocate peat (excavate peat for development and then reuse it where there is a need e.g. due to cut and fill balance) rather than remove from site. There were concerns the Carbon Calculator assumes a worse-case scenario. Consideration of whether the Carbon Calculator should incorporate an option to include peat reuse needs to be weighed up against whether this would be appropriate, as the reuse of peat is site specific, i.e. there will be limited sites with options appropriate for peat reuse, and unless peat for reuse is handled carefully it is likely to oxidise over time and lose carbon to the atmosphere. Options for positive reuse are highlighted as an evidence gap and would require additional research prior to updating the Carbon Calculator.

Key consideration: Incorporate minimum and maximum parameters into the Carbon Calculator for the carbon content of dry peat and dry soil bulk density variables

These two variables have a significant impact on the Carbon Calculator output. The literature review has identified an acceptable range for both variables which could act as parameters and inform quality control.

Key consideration: the use of HRSD

A recent study from JHI explored the mapping of soil profile depth, bulk density and carbon stock in Scotland using remote sensing and spatial covariates (Aitkenhead and Coull, 2020), Although further research is required to determine the appropriateness of this approach, in relation to bias in datasets, model complexity and comparison, model performance, and separate models for interrelated properties, and further engagement with JHI and NatureScot on the role of HRSD in this context is recommended as a next step. 

Scientific accuracy: Peat drained

  • Calculating volume of peat drained:
    • Volume of peat drained is calculated based on the depth of the drain and the extent of drainage. However, accurately establishing drainage efficacy is complicated as it affected by other parameters which are not well documented, and the changes brought about by drainage are expressed over a long period of time (IUCN, 2014).
      • In pristine peatland the water table is typically close to the surface. As a result of excavation, drainage causes a drop in the water table (Irish Peatland Conservation Council, n.d.). This stimulates soil respiration and the release of carbon (Ma et al., 2022).
      • Drainage also leads to subsidence (Ma et al., 2022) (IUCN, 2014). Subsidence should be measured alongside the water table depth to fully inform the likely extent of drainage.
      • Drainage can be influenced by distance between ditches, hydraulic conductivity, and slopes (Price et al, 2023).
      • There is a linear relationship between age of a drain and the cumulative carbon lost (Evans et al, 2021).
      • Within degraded peat, the local formation of drainage ‘pipes’ is common, therefore possibly enhancing the extent of drainage.
    • Despite research in the area there is an evidence gap in understanding what a suitable average is, and the methodologies to define the extent of drainage are difficult to apply.
  • Calculating CO2 loss from drained peat:
    • In flooded soils, CO2 emissions are equalled or exceeded by fixation leading to near-zero emissions or net carbon sequestration, whilst in drained soils CO2 emissions exceed fixation leading to net emissions. The carbon emissions associated with peat drainage are calculated based on the difference between emissions from drained land and emissions from undrained land.
    • If site is not restored after decommissioning: The Carbon Calculator assumes a worse-case scenario that all carbon is lost (i.e. full drainage) following the same approach as removed peat. Due to the uncertainty in the parameter of the extent of drainage, this approach provides an appropriate worst-case scenario.
    • If site is restored after decommissioning: The Carbon Calculator calculates emissions from drained land against the lifetime of the wind farm, restoration period (as defined by the user) and considers the number of flooded days per year based on IPCC (1997) assumptions, which should be updated to reflect more recent literature (see below ‘calculating emission rates from soils’). Due to the uncertainty around end-of-life and decommissioning it may be more appropriate to assume a worse-case scenario (i.e. assume site is not restored after decommissioning), and separately account for the benefits from restoration within the ‘CO2 gain – site improvement’ tab so that it is reported separately to the impact during the lifetime of the wind farm.
    • See Section 3.8.1 for commentary on ‘carbon content of dry peat’ and ‘dry soil bulk density’ data inputs.
  • Calculating emission rates from soils:
    • The purpose of this calculation is to determine the loss of soil carbon in the peatland as a result of a wind farm development. This is calculated from the total carbon loss from physically removed peat, and total carbon loss from peat drainage.
    • There are two approaches included within the Carbon Calculator – the IPCC methodology is a default approach and excludes any site detail; the model used by Nayak et al, 2008 is provided as a site-specific option. Users have the option to use either the IPCC (1997) methodology or the site-specific methodology. However, the Carbon Calculator states the site-specific method must be used for planning applications. If the IPCC (1997) methodology is redundant, it should be removed from the Carbon Calculator.
    • IPCC 1997:
      • This has been superseded by the 2014 Wetland Supplement.
      • Whilst the Carbon Calculator does not include N2O (as it uses IPCC (1997) emission factors), the implications of this are small, and further updates could be made to include this. Whilst not expected to be a significant emission (ca. 2%) and dependent on the nutrient content of soils, it could be incorporated based on nitrogen content of soil samples. Where relevant (in the instance of intensive farming) N2O emissions could be comparable to CH4 .
      • The IPCC emission factors referenced are Tier 1, and therefore not representative of Scotland’s peatlands. The factors are mainly based on warm season data, and peatlands in colder climates are likely to emit less (Hongxing and Roulet, 2023).
      • Although these Tier 1 emissions factors could be updated by those represented by Evans et al, 2023 (Tier 2) and used within the 2021 update to the Emissions Inventory for UK Peatlands, they may not be fully representative of Scotland (which is wetter, and agriculture is predominantly less intensive). Furthermore, the Carbon Calculator states the site-specific method must be used for planning applications. It is therefore recommended that the IPCC (1997) methodology is removed due to the greater accuracy that the site-specific methodology can provide.
    • Nayak et al, 2008:
      • Calculates emissions factors via a bespoke methodology. Two options for type of peatland provided: acid bog, and fen (core data inputs). This covers the four main peatland habitats in Scotland; blanket bog (acid bog), raised bog (acid bog), fen (fen) and bog woodland (acid bog).
      • The methodology equations for CO2 and CH4 emissions are derived by regression analysis, considering the average annual air temperature and average water table depth. Whilst the methodology does not directly refer to peatland condition, it incorporates air temperature and water table depth which is a good proxy in establishing emission rates (Tiemeyer et al., 2020) (Ma et al, 2022), as the water table has a significant influence on peatland CO2 and CH4 emissions (Huissteden et al, 2016, Evans et al, 2021). Empirical relationships between water table depth and CH4 and CO2 emissions defined by Evans et al (ibid) enable it to be used to calculate carbon emissions, as illustrated by Evans et al (2023).
      • The evidence base for the methodology uses multiple peer reviewed studies (Bubier et al. 1993, Martikainen et al. 1995, Silvola et al. 1996, MacDonald et al. 1998, Nykänen et al, 1998, Alm et al. 1999), the analysis includes a robust sensitivity analysis which supports accuracy. However, the studies referenced reflect boreal peatland, and this element of the Carbon Calculator could be updated to reflect more recent literature ( (Evans et al, 2021), (Evans et al, 2023), (Ojanen and Minkkinen, 2019), (Wilson et al, 2016), (Tieymer et al, 2016)) which reflects a temperate climate and/or accounts for land use type.

Usability: Peat drained

  • Calculating volume of peat drained:
    • The volume of peat drained is highly sensitive to the user input for the ‘average depth of peat removed’ from each development feature (i.e. ‘average depth of peat removed from borrow pit, hard standing, turbine foundations’); increasing the depth and/or extent of drainage directly correlates with the volume of peat effected by drainage. This volume feeds into the calculations for CO2 loss from drained peat.
    • The average water table depth and extent of drainage is a user input. These parameters vary depending on the specific site, and within the site itself. Authors of the Carbon Calculator, Nayak et al (2008) underline the importance of accuracy in the choice of these inputs. However, the cost of correctly following the methodologies presented in the Carbon Calculator were highlighted by industry stakeholders as ‘prohibitively high’ for projects that may not obtain planning consent.
      • Average water table depth variable: The Carbon Calculator describes this variable as the upper boundary of the groundwater. Considerable variety in the method used to obtain the ‘average water table depth’ by users was observed – from obtaining an average depth via hydrologists, to using the water table depth from a previous similar site. Evidence of the hydrology calculations to inform user inputs were not assessed as part of this research, and could merit further research in conjunction with a review of other EIA deliverables and their applicability to the Carbon Calculator’s data inputs. The narrow timescales associated with the preparation of planning documents (i.e. EIA) present a challenge in obtaining reliable information, and the current approach does not account for the temporal changes of the water table. The Carbon Calculator output likely only represents a ‘snapshot’ which consequently, in combination with the variety in approaches to obtaining the variable, may be inaccurate.
      • Average extent of drainage around drainage features at site’ variable: Industry feedback on this variable’s method was resolute in it being impractical to collect this data (due to both time requirements and associated cost) during planning timescales. Despite reviewing available evidence, a practical methodology (i.e. within planning timescales) to inform this variable could not be identified.
  • Calculating CO2 loss from drained peat:
    • See Section 3.8.2 for commentary regarding carbon content of dry peat and dry soil bulk density.
  • Emission rates from soils:
    • See Section 3.8.2 for commentary regarding emission rates from soils.

Key consideration: update the methodology for emissions rates from soils

The methodology should incorporate recent literature and a temperate peatland that reflects the Scottish context, it should also acknowledge the role of the mean annual water table depth, which has been identified as the overwhelmingly dominant control on CO2 fluxes (Evans et al, 2021). The literature review identified papers which should be reviewed when undertaking this update:

  • Tiemeyer et al (2020)’s ‘A new methodology for organic soils in national greenhouse gas inventories: Data synthesis, derivation and application’ incorporates HRSD and uses water table data to determine Germany’s GHG estimate for organic soils at a National level, which it states could be applied at a project level.
  • Evans et al (2023) ‘Aligning the Peatland Code with the UK peatland inventory’ provides an overview of low-cost methodologies to obtain site data to inform peat-carbon variables, including water table depth and reference to ‘Eyes on the bog’ methodologies (Lindsey et al, 2019).

Key consideration: should the Carbon Calculator account for emissions from drainage ditches?

Although the extent of drainage is captured in the Carbon Calculator, drainage ditches represent an additional source of CH4 emissions from drained organic soils (Peacock et al, 2021) which are not currently included in the calculations. Emissions from ditches are captured in the IPCC’s 2014 Wetlands supplement and could be applied to developments if the Carbon Calculator were to specify to peat condition, to replicate the approach used in the Peatland Code (Evans et al, 2023). The inclusion of drainage ditches could also be informed by the use of HRSD (see 3.8.12).

Key consideration: Investigate the use of HRSD in measuring water table depth

HRSD can be utilised to ascertain water table depth and provide historic trends. This could enhance the accuracy of Carbon Calculator when combined with ground truthing. For more information, please see Section 5. This could also inform Quality Control Mechanisms.

Key consideration: to what extent can assumptions/parameters, and HRSD be used to inform ‘Average extent of drainage around drainage features at site’?

The current methodology to obtain the extent of drainage is viewed as being impractical within planning timescales. Whether this variable (using an indicative assumption) should be automated, and/or include parameters, requires careful consideration, particularly as it is a highly sensitive input. The IUCN classifies drained peatland as that which lies within 30m of an active drain, (IUCN, 2022). The literature review was unable to determine a range to inform parameters on this variable, although it did identify a paper where GIS was utilised to establish surrounding drainage areas (Sallinen et al, 2019). The role of HRSD in informing this input variable should be considered in conjunction with other efforts being undertaken to establish better accuracy in quantifying drainage impacts. This includes work undertaken (and ongoing) at the James Hutton Institute (e.g. Aitkenhead et al, 2016, the Peat Mothership Project (2024)) to inform the best approach. Discussion of the draft report highlighted an additional study utilising HRSD to provide a national scale map of Scotland’s individual drainage channels and erosion features (Macfarlane et al, 2024) which would further inform the role of HRSD in this context and Section 3.8.10.

Key consideration: what quality control mechanisms are needed to enable a consistent (and accurate) approach to obtaining WTD and extent of drainage?

Industry feedback consistently highlighted concerns around the time and cost in obtaining the input variables required for extent of drainage and water table. These variables have a significant bearing on the carbon outputs, and so the approach to obtaining them should be uniform and feasible within planning timescales. This could be remedied through further engagement, the subsequent development/updating of guidelines (i.e. Guidance on Developments on Peatland, 2017), and/or the provision of training (to users and decision makers) and reinforced through the appropriate use of quality controls. This data could then go on to inform a national dataset of measurements.

Assessment findings: CO2 loss by Dissolved Organic Carbon (DOC) and Particulate Organic Carbon (POC) loss

Scientific accuracy

  • This area of the Carbon Calculator determines the gross loss of soil carbon from both DOC and POC loss following peat drainage. Only restored formerly drained land is included in this calculation because if land is not restored, the carbon lost has already been counted as carbon dioxide via ‘CO2 loss from drained peat’ (Section 3.8.7). CO2 loss by DOC and POC has a low significance within the outputs of the Carbon Calculator, most CO2 losses due to wind farm development is associated with soil organic matter (see Appendix 10.2).
  • The Carbon Calculator advises that “No POC losses for bare soil included yet. If extensive areas of bare soil is present at site need modified calculation (Birnie et al, 1991)”.
  • Assuming site restoration, DOC and POC are calculated for the period (years) of site restoration (i.e. the time between the year of site improvement and the year of the sites habitat and hydrology being restored).
  • Emissions are calculated based on a percentage of the total gaseous losses of carbon from improved/restored land, these are based on averages from Worrall (2009) which provide the following:
  • DOC – 26% (7-40%)
  • POC – 8% (4-10%)
  • These assumptions (including the minimum and maximum) are tied into the Carbon Calculator (i.e. not editable by the user). DOC has a broad range, which could be causing some inaccuracy in the results. The Carbon Calculator’s assumption that DOC and POC loss is only applied to restored formerly drained sites may be underestimating DOC and POC emissions for sites which have eroding peatland.
  • The Peatland Code methodology Smyth et al. (2015) uses DOC and POC emission factors (reflecting condition type) which follow Tier 1 default values for drained and rewetted temperate peatlands developed for the IPCC Wetland Supplement (IPCC, 2014). Evans et al (2023) note for DOC that few limited UK studies have been published, and other studies fall outside the UK-relevant climatic region; and similar for POC; few additional POC flux estimates exist to enable refinement. Although some recent UK evidence indicates DOC increases may be larger or smaller depending on the peatland type, there is insufficient DOC flux data across the range of UK peat types and condition classes to support a full country specific approach (ibid).
  • Pickard et al (2022) found that increased DOC concentrations were detected in areas of drained peatland relative to non-drained peatland from the UK’s largest tract of blanket bog in the Flow Country of northern Scotland. These findings could be incorporated into the Carbon Calculator, however, as they represent one study based on a unique area of pristine peatland, a more conservative approach is recommended until further research is available.
  • Discussion of the draft report raised an additional study from the Whitlee wind farm development exploring the effect of development phasing in relation to DOC and POC loss over a ten-year timespan, we suggest that further review incorporates the findings from this study.

Usability

  • DOC and POC calculations require no inputs from the user.

Key consideration: align DOC and POC with the 2014 IPCC Wetland Supplement

For the purposes of the Carbon Calculator, emissions factors for DOC and POC could be applied to projects based on the peat condition, utilising the IPCC 2014 methodology, replicating the Peatland Code (Evans et al, 2023) which uses the UK inventory emissions factors. This would replace the current methodology but is more robust as the studies used to inform these default factors were based partly on a small number of UK studies (including two from Worrall), rather than a single study as currently used. This approach would have the added benefit of capturing DOC and POC emissions that are already occurring on eroding peatland and provide greater accuracy. The literature review highlighted an evidence gap where additional research is required to provide more specific DOC and POC estimations, building on the findings from Pickard et al (2022).

Assessment findings: CO2 losses associated with loss of forest

Scientific accuracy (simple)

  • The simple methodology for forestry CO2 loss uses figures obtained from a single source (Cannell, 1999). Loss of future carbon sequestration is calculated by multiplying an emission factor by the area of forestry and lifetime of the wind farm. In the simple methodology this is a user input, “estimated carbon sequestered (t C ha-1 yr-1)”. The guidance note provides an assumption of 3.6 tC ha-1 yr-1 for yield class 16 m3 ha-1 y-1 (Cannell, 1999). Whilst this is comparable with an average (over 200 years) from the Woodland Carbon Code (Yield 16, 1.7m spacing, thinned) Woodland Carbon Code, 2024) it doesn’t consider aspects such as species, age, density etc of the site-specific parameters. Therefore, a level of uncertainty/ error can be inferred for users with differing site characteristics (tree species).
  • There is no consideration of emissions associated with the felling activities. Whilst this is likely to be insignificant, it could be incorporated into the Carbon Calculator for completeness.
  • There is no consideration of emissions associated with the loss of carbon stock (i.e. if the felled forest wood is destroyed), which depending on the use of the wood could be relevant (e.g. if the timber is burnt).
  • There is no consideration of the impact on the peatland of removing the trees (where forestry is located on peatland). Whilst expected to have a positive impact over time on peatland restoration, it is acknowledged that further research is required in this area (Howson et al, 2021; IUCN, 2020).
  • Based on our sensitivity analysis results (Table 3) from the simple and detailed methodology vary significantly based on similar parameters:

Table 3: Forest methodologies sensitivity analysis

Simple methodology

Data inputs

Area of forestry plantation to be felled (ha)

100

Average rate of carbon sequestration in timber (tC ha-1 yr-1)

3.6

tCO2e

33,003

Detailed methodology (presenting a reference scenario comparable to the simple methodology and subsequently scenario adjustments to consider the sensitivity of each input variable)

Data inputs

Reference scenario

Scenario 1

Scenario 2

Scenario 3

Scenario 4

Scenario 5

(Peat type)

(Species)

(Age)

Soil type

Deep peat

Peaty gley

    

Area to be felled (ha)

100

     

Width of forest around felled area (m)

1

     

Tree species

Scots pine

 

Sitka spruce

   

Age (yrs.)

10

  

5

20

40

tCO2e

99,465

90,149

110,282

98,170

100,625

96,990

  • This is due to the simple methodology not accounting for/underestimating the following:
  • Tree species and age.
  • cleared forest emissions (currently labelled ‘carbon sequestration in soil under trees’ in the detailed methodology).
  • Underestimating the amount of carbon lost due to felling in comparison to the detailed methodology (likely because of the additional variables that inform the detailed methodology – light interception and primary production).

Usability (simple)

  • The input variables are acceptable in terms of usability. However, there is the potential for error with the current input variables guidance. The Carbon Calculator notes that sequestration rate is dependent on the yield class of the forestry. The guidance note provides an assumption of 3.6 tC ha-1 yr-1 for yield class 16 m3 ha-1 y-1. No guidance is provided as to how the species of tree influences yield class, although poplar, Sitka, and beech CO2 sequestration rates are provided in the separate user Guidance document, they are not visible in the Carbon Calculator. Enhanced user guidance and/or reference to sources of information (e.g. The Woodland Carbon Code) could be provided.

Scientific accuracy (detailed)

  • The detailed method uses similar principles to the simple method, however, differs in its calculation of ‘the average carbon sequestered per year’, it requires additional user input (‘forestry input data tab’) to account for carbon loss based on soil type, species, and age of forestry, and provides a more complete account of the emissions from forestry in comparison to the simple methodology (see Table 3) .
  • The method which informs these calculations (Xenakis et al, 2008) is comprehensive in calculating emissions from forestry. It uses the uses 3-PG (Landsberg, J.J., Waring, R.H., 1997). A generalised model of forest productivity using simplified concepts of radiation-use efficiency, carbon balance and partitioning, and builds on this to incorporate a soil organic matter decomposition mode, incorporating differences due to age of forestry at felling. The model has been calibrated and tested for commercial plantations of Scots pine in Scotland.
  • ‘Carbon sequestration in soil under trees’: is noted within the Carbon Calculator as ‘more data needed’. ‘ It states that the aim of this calculation is to ‘account for the respiration from newly felled and disturbed soil, so as to include respiration from fresh plant inputs, from background soil organic matter decomposition, and from the disturbance of soil resulting in the release of additional carbon from soil aggregates. Different types of management disturbance should be considered’. This is labelled as ‘Cleared Forest Floor Emissions’ within the Carbon Calculator. It later states that this information is not yet available, so as an interim measure, carbon sequestration in soil under trees (including background respiration from soil organic matter decomposition and respiration from fresh plant input) is used.
  • The two emissions factors currently used for the ‘Carbon sequestration in soil under trees’ are based on two studies located in Scotland which is appropriate. However, both studies assumes that forestry is on peaty soils, which may not be the case for all forestry inputs. Given that this element of the Carbon Calculator was originally planned to account for the ‘Cleared Forest Floor Emissions’ only (see previous paragraph), the emissions factors used in lieu of this are possibly overestimating the carbon sequestration associated with soil under trees. Since this literature was published, there has been further research to understand the relationship between carbon emissions and newly felled/disturbed soils (West, 2011) (Matthews et al. 2012), these studies have informed the development of the Woodland Carbon Code (2024).
  • The detailed methodology also provides a calculation to determine the capacity factor for the turbines at the site. This is dependent on tree height, forest width and distance of the forest from the turbine. Although this methodology appears scientifically correct in terms of the measurements being used, none of the references provide justification of the overarching rationale/purpose of this calculation. Some of the references used for wind speed calculations are over 20 years old and it’s unclear whether these factor in the impacts of climate change on wind speeds. The technological advances in turbine functionality (and the extent to which they are impacted by forestry) needs to be considered. It is also reasonable to assume that the potential capacity of the wind turbines and influence of forestry on a wind turbine’s power curve will be considered by developers when establishing the Levelised Cost of Electricity (i.e. site feasibility) for a development. Overall, the appropriateness of this calculation in the context of the Carbon Calculator’s purpose is questionable and should be removed (see 3.3.4 Key consideration: Is the focus of the Carbon Calculator, correct?).

Usability (detailed)

  • Feedback from industry engagement highlighted that the detailed methodology is not used as the number of input variables required is perceived as onerous/requiring specialist support.
  • The forestry input data tab provides two options for soil types provided: peaty gley and deep peat. This appropriately covers both peat (organic) soils and peaty (organo-mineral) soils.
  • The forestry input data tab provides two options for species: Scots pine and Sitka spruce. Scots pine is the main species in bog forests (NatureScot, n.d) the inclusion of other species may be beneficial in providing a more accurate output.
  • The separate user Guidance document states the following: ‘Loss from soils of non-forested land is given by the estimated rate of carbon loss for two peat depths taken from Zerva et al (2005) for peaty gley (peat depth 5 to 50cm = 3.98 t C ha-1yr-1), and Hargreaves et al (2003) for deep peat (peat depth>50cm = 5.00 t C ha-1 yr-1)’. The reference to ‘non-forested land’ in the Guidance may be an error given the references used.
  • Emissions from felling and transportation are a user input; these could be estimated based on assumptions and utilisation of UK Government emission factors. The existing guidance notes provide outdated references (Morison et al, 2011). The most up-to-date UK Government emission factors should be used and could be automated within the Carbon Calculator.

Key consideration: Replace the simple and detailed methodologies with one approach, informed by Woodland Carbon Code calculations

Although the detailed forestry methodology is comprehensive, it is perceived as onerous/requiring specialist support by users, and so in many applications the simple methodology is used. The simple methodology is likely to be underestimating carbon impacts. In turn, the detailed methodology may be providing inaccuracies in relation to ‘Carbon sequestration in soil under trees’. The comprehensive nature of the detailed approach also has implications for the ability to ‘futureproof’ the Carbon Calculator. The equations which inform it and the formula within the Calculator, are complicated and difficult to interpret without advanced excel skills. This presents a risk when undertaking future updates to the Carbon Calculator.

Having one option in the Carbon Calculator which strikes a balance between inputs required and the generation of an accurate output is an important consideration. The Woodland Carbon Code’s (WCC) (Woodland Carbon Code, 2024) calculator includes a wider range of tree species with rates based on spacing (m), yield class, management type and age. The WCC is supported by Scottish Forestry and has undergone independent validation and verification. It provides a credible dataset that is reviewed and updated regularly. To enable a more robust output, the sequestration rates ‘Biomass Carbon Lookup Table’ could be replicated in the Carbon Calculator and aligned with the WCC to enable consistency in reporting methods.

Key consideration: Remove the option to affect the wind turbine’s capacity factor via the forestry inputs tab

The calculations that inform this appear to go beyond the remit of this Section’s purpose in calculating the CO2 losses associated with forestry. More rationale on why this is not appropriate and should be removed is provided in Section 3.10.3 bullet point 6.

Key consideration: Use of HRSD in determining forestry inputs

The role of HRSD and whether it could be utilised to determine key input variables for forestry and/or estimated carbon stocks (see Tolan et al, 2024, Cheng et al, 2024, which use cutting edge technology to estimate carbon stocks) should be explored in collaboration with forestry organisations (i.e. Scottish Forestry, NatureScot, Forestry and Land Scotland, Forest Research). There are several open resources that could inform this (i.e. Scottish Forestry Map viewer (Scottish Forestry, n.d.), Habitat Land Cover Map of Scotland (2024), Scottish Remote Sensing Portal (Scottish Government, n.d.)). Process-based modelling, data assimilation and remote sensing has been applied by the University of Edinburgh to quantify carbon stock changes, and remote sensing is used by Forest Research to accurately map woodland.

Assessment Findings: CO2 gains from site improvement

Scientific accuracy

  • This area of the Carbon Calculator estimates the reduction in GHG emissions due to restoration of the site. The calculation for this area of the tab replicates the calculation used to ascertain loss of soil CO2 (peat drained) (Nayak et al, 2008), and so the findings from 3.8.7 and 3.8.8 are also relevant to this section.
  • The current calculations assume that restoration will be successful, and that peatland will be restored to pristine condition. The UK Inventory and Peatland Code transitions land from degraded condition categories to ‘modified bog’ upon restoration, it does not apply the ‘near-natural’ emission factor to restored peatland, recognising the difficulty in fully restoring peatland to the full sequestration potential.
  • It is difficult to accurately model emission reductions associated with restoration at pre-planning phases – in particular, the ‘depth of peat above the water table after restoration.’ There are several restoration activities (hydrology and habitat ‘yes/not applicable’ inputs) within the Carbon Calculator are assumed to occur post wind farm operation (>20 years in the future), although these are not linked to any calculations.
  • Undisputed, is that the restoration of degraded sites should be a priority, and the benefits of such activities are well documented. However, there is variation in understanding the impact of restoration on carbon savings. How restoration affects carbon fluxes and storage on degraded sites shows variety in the potential results. Peatland recovery is not instantaneous (Gatis et al.,2023, Alderson et al, 2019), with interventions taking at least 5 years or more for ecosystems changes to stabilise (Gregg et al., 2021). Artz et al. (2012) note that carbon savings are dependent on the starting condition prior to restoration with some research indicating that severely degraded sites take longer to achieve emissions reduction than less affected peatlands. Restoring the carbon ‘sink’ functionality of a degraded peatland is possible, however this may take decades, and be dependent on the initial level of site degradation (Gregg et al., Ibid). Lindsay (2010) notes that peat accumulation in blanket bogs can be half that of raised bog due to warmer climatic conditions and suggests a timeframe of around four decades before restoration to a fully functional bog can achieve net carbon gain, although emissions reduction will occur much earlier. Although there can be short term CH4 fluxes because of restoration the long-term carbon savings can negate this short-term effect (Emsens et al., 2021– note this study relates to fen bogs, but also highlights the important role of vegetation establishment). Evans et al. (2022) note that independent modelling studies by Heinemeyer et al. (2019) for the Defra Peatland-ES-UK (Defra BD5104) project, and Simon et al. (2021) for the BEIS review of UK GGR potential both suggested that degraded peatlands have the potential to accumulate carbon rapidly, and therefore that the CO2 sequestration potential of peat restoration may have been significantly underestimated. The current methodology does not take these considerations into account.
  • Future climate conditions (e.g. rising temperatures, extreme weather events) could affect the ‘success’ of peat restoration (i.e., carbon accumulation). Climate change is noted to exacerbate ecological stresses on less resilient, managed peatlands over the next 60 years, leading to more rapid losses of stored peat carbon (Worral et al, 2010) (Ferretto et al, 2019) (Natural England, 2020). Any estimates made have a high level of uncertainty, given the relatively short timeframe of restoration in the context of a wind farm’s lifespan.
  • The calculations for site restoration are sensitive to water table depth changes, pre- and post-restoration (Appendix 11.3). Water table has a significant influence on peatland CO2 and CH4 emissions (see section 3.8.7). However, there is limited empirical data to provide a high level of certainty in relation to future carbon stocks and carbon flux; carbon benefits can be difficult to quantify and affected by environmental conditions on a site-by-site basis (Wille et al, 2023), Gregg et al. (2021) state in relation to blanket bogs, raised bogs and fens that ‘large spatial variability has been shown and studies have often been carried out at the same sites or regions’, blanket bogs are less responsive to drainage and rewetting alone, but can be beneficial when coupled with peatland stabilisation and re-establishment of vegetation cover, the role of vegetation as well as hydrology in site restoration should therefore be taken into account. Further research is required in the context of restoration, including blanket bog rewetting (Evans et al., 2014; Williamson et al., 2017), and restoration of plantations to semi-natural peatland.
  • See also the commentary on ‘emission rates from soils’ within Section 203.8.

Usability

  • Calculations within this tab are based on the changes to water table depth pre- and post-restoration of peat (inputted by the user) and the calculated emission rates from soils. It has been noted that small changes to the figures for water table depth can significantly increase the value of carbon gains due to peat restoration. Although the methodology for ‘Water table depth after improvement’ variables indicate an optimal water table level is ‘probably just below the surface (-10 to -6 cm)’, within planning timescales the future water table depth (and other associated variables) can only be approximated. When accounting for the high level of uncertainty regarding restoration, the question of whether this element of the Carbon Calculator should be conventionalised to replicate the Peatland Code’s calculations and guidance requires consideration.
  • See also commentary on ‘emission rates from soils’ within Section 203.8.

See 3.3.3 key consideration: is the output of the Carbon Calculator useful as a decision-making tool?

The timeframe for achieving a ‘carbon payback’ or ‘carbon neutrality’ should be considered on a land for land basis (e.g. restoration gains vs construction losses) instead of relying on savings from generation. More information on how this should be presented is provided in 3.3.3.

Key consideration: the Carbon Calculator should be updated to replicate the Peatland Code

Site restoration should explore the option to replicate elements of the Peatland Code’s approach, including its requirements around restoration success. In particular, the Peatland Code utilises up-to-date emissions factors (aligned with the UK inventory), and includes a 15% sensitivity buffer to accommodate the risk of future carbon losses (e.g., restoration failure) (see Section 4 on the Peatland Code). Establishing a baseline condition that reflects the Peatland Code’s classification, would simplify the input required for site restoration (by then selecting the appropriate condition post-restoration). Considering the degree of uncertainty, this is appropriate and could prevent the risk of inaccuracy and/or ‘fixing’ of the current variables. This would negate the use of ‘carbon fixing’, ‘loss of DOC and POC’, and ‘peat drainage after restoration’ calculations. By bringing different funding mechanisms together, this alignment could also support data collection at a national restoration level. Through our engagement with the Peatland Expert Advisory Panel, it was determined that the full implementation of the Peatland Code on development sites is not suitable. Further dialogue with the Peatland Code representatives is recommended to identify the optimal approach for this consideration.

Key consideration: Quality control should review the Carbon Calculator in conjunction with the Peat Management Plan (PMP) and Habitat Management Plan (HMP)

In determining whether a development should be built on peatland, a key decision factor should be the extent to which the developer is able to illustrate site restoration post installation, reflecting the requirements of NPF4 (mitigation hierarchy) and Good Practice restoration Guidance (e.g. NatureScot, Peatland Code). Resilient restoration through credible restoration techniques which prioritise vegetation establishment and a return to high water tables are critical components of this. The remit of the Carbon Calculator is to determine whether the carbon impact of the development on peatland is acceptable, any carbon savings from site restoration should be reviewed holistically in conjunction with a robust PMP and HMP that evidences credible restoration techniques. To inform this, a review of the requirements for key EIA deliverables (i.e. PMP, HMP, Carbon Calculator) could be undertaken, to enable a streamlined decision-making process. 

Summary

Based on the findings from the technical assessment and evidence review, Table 4 presents a summary of the Carbon Calculator’s scientific accuracy and data usability ratings.

Table 4. Carbon Calculator areas summary

 

Areas of the Carbon Calculator

RAG rating Scientific accuracy

RAG rating Data usability

3.2

Data inputs


Amber


3.3

Payback time and CO2 emissions


Red



Amber


3.4

Wind farm CO2 emission savings


Red



Green


3.5

Emissions due to turbine life


Red



Amber


3.6

Loss of carbon due to back up power generation


Red



Green


3.7

Loss of carbon fixing potential of peatlands


Amber



Amber


3.8

Loss of soil CO2

 
  • Peat removed

Amber



Amber


 
  • Peat drained

Red



Red


3.9

CO2 loss by DOC and POC loss


Amber


3.10

Loss of carbon due to forestry loss

 
  • Simple

Red



Amber


 
  • Detailed

Amber



Red


3.11

Carbon saving due to improvement of peatland habitat


Red



Red


In summary, the ‘payback time and CO2 emissions’ is not relevant/consistent with the findings of the technical assessment and literature review. The focus of the Carbon Calculator (3.4) requires revisiting, with consideration of whether 3.5. and 3.6. are required considering new planning policy and applicability of WLCAs.

Accuracy is lacking in one or more of the following: methodologies, use of emission factors and assumptions, for all peat-related areas of the Carbon Calculator, as well as the forestry area. The usability of the Carbon Calculator presents a more varied picture, with some data accessible to the user. However, there was uncertainty in the ability to accurately access some of the data required for the Carbon Calculator – in particular, for variables that drive the results, which could have a material bearing on the accuracy of outputs.

Further commentary is provided in 7. Conclusion and recommendations.

SWOT analysis

Table 5 presents the strengths, weaknesses, opportunities, and threats of the current Carbon Calculator identified from this Report’s findings:

 

Table 5: SWOT analysis

Strengths

  • Allows previous iterations of inputs to be saved and updated.
  • Used by applicants for over 16 years.
  • User guidance document and detailed guidance within the Carbon Calculator are provided.
  • The data variables for Wind farm CO2 emission savings are site specific, are available to the Carbon Calculator user, and support an accurate output.
  • The data variable for Emissions due to back up power, is available to the Carbon Calculator user.
  • The calculation methodology for calculating CO2 loss from removed peat is appropriate.
  • DOC and POC calculations require no inputs from the user.
  • The method which informs the detailed forestry tab is comprehensive.

Weaknesses

Accuracy

  • Accuracy is lacking in one or more across methodologies, use of emissions factors and assumptions for Loss of CO2 fixing potential, due to not considering the condition of the peatland. However, it has a very small bearing on carbon output.
  • Accuracy is lacking in one or more across methodologies, use of emissions factors and assumptions for Loss of soil CO2 (peat removed), due the use of averages.
  • Accuracy is lacking in one or more across methodologies, use of emissions factors and assumptions for CO2 loss by DOC and POC loss, due to more recent literature updates.
  • Accuracy is lacking in one or more across methodologies, use of emissions factors and assumptions CO2 losses associated with loss of forest (both simple and detailed).

Usability

  • The user is required to input a high number of variables (i.e. for the core input data, 70 input variables are required). Each input variable requires an expected value, as well as a minimum and maximum range, therefore over ~200 input variables are required in total for core inputs, this has been highlighted as cumbersome by some users.
  • The peatland related carbon emissions are presented to the user as a small proportion of overall carbon emissions because the emissions from the wind turbine are far greater.
  • There is some uncertainty around the data availability for Emissions due to turbine life, this may be causing double counting in foundations emissions, and this area of the Carbon Calculator may be redundant with the development of WLCA.
  • There is some uncertainty around data availability for Loss of soil CO2 (peat removed) due to it being difficult to obtain some of the variables and/or assumptions used.

Opportunities

  • Replace the use of averages with infrastructure specific inputs, this approach would provide more accurate outputs, improved usability, and replicate how peat is reported on in the PMP.
  • Opportunity to remove/option to ‘opt out’ of minimum and maximum variables where site specific data is known and can be evidenced by the user, reducing number of inputs required overall.
  • Opportunity to present the impact of development on peatland via the baseline site conditions and ‘payback’ time to a restored site in relation land use emissions.
  • Opportunity to illustrate a ‘counterfactual’ that demonstrates the benefits of restoration without development taking place (if restoration takes place as a result of Scotland’s proactive approach and financial mechanisms that support restoration)
  • The emissions associated with wind turbine LCA, back up requirements, and current ‘payback’ approach could be removed from the Carbon Calculator as existing tools and approaches exist for WLCA.
  • Opportunity to incorporate minimum and maximum parameters into the Carbon Calculator to support quality control.
  • Evidence gap – in relation to bog fixing potential and peatland condition relationship.
  • The use of HRSD could support the identification of peatland condition, as well as ascertaining water table depth and providing historic trends. This could enhance the accuracy of the Carbon Calculator when combined with ground truthing and inform Quality Control Mechanisms.
  • Further research/engagement with JHI could inform estimating the ‘Average extent of drainage around drainage features at site’ and ‘soil bulk density’ input via HRSD and/or GIS.
  • Further engagement, the subsequent development/updating of guidelines, and/or the provision of training (to users and decision makers) would support quality control. Data outputs from applications could then go on to inform a national dataset of measurements.
  • Opportunity to align DOC and POC with the 2014 IPCC Wetland Supplement to capture DOC and POC emissions that are already occurring on eroding peatland and provide greater accuracy.
  • Opportunity to Replace the simple and detailed methodologies with one approach, informed by Woodland Carbon Code calculations (which is supported by Scottish Forestry and has undergone independent validation and verification).
  • Opportunity to align the inputs used in PMPs, HMPs and other related EIA deliverables with the Carbon Calculator’s inputs to streamline decision making.
  • Opportunity to integrate the Peatland Code calculation methodology to support greater accuracy.
  • Opportunity to evolve the Carbon Calculator to assess more land use types.
  • Opportunity to evolve the Carbon Calculator to assess different infrastructure/development types.

Threats

  • The focus of the Carbon Calculator and ‘Payback time and CO2 emissions’ in calculating the lifecycle emissions of wind farms based on a counterfactual of electricity generated by fossil fuels no longer accurately represents the impact of developments on peatland.
  • The methodologies, use of emissions factors and assumptions are not relevant/consistent with findings of the literature review for Wind farm CO2 emission savings, the assumptions are not representative of current context.
  • The methodologies, use of emissions factors and assumptions are not relevant/consistent with findings of the literature review for Emissions due to turbine life. The assumptions are out of date.
  • The methodologies, use of emissions factors and assumptions are not relevant/consistent with findings of the literature review for Emissions due to back up power generation, there are no specific requirements for back-up, and this area of the Carbon Calculator may be redundant.
  • The methodologies, use of emissions factors and assumptions are not relevant/consistent with findings of the literature review for Loss of soil CO2 (peat drained) due to new literature findings.
  • The methodologies, use of emissions factors and assumptions are not relevant/consistent with findings of the literature review for CO2 gains from site improvement, due to uncertainty in the method, and new literature findings.
  • Data for Loss of soil CO2 (peat drained) is inaccessible to the user, for extent of drainage and water table, and this has a material impact on the outcome of the Carbon Calculator.
  • Data for CO2 losses associated with loss of forest (detailed) is inaccessible to the user, and this has a material impact on the outcome of the Carbon Calculator.
  • The comprehensive nature of the detailed forestry approach has implications for the ability to ‘futureproof’ the Carbon Calculator. The equations which inform it and the formula within the Carbon Calculator, are complicated and difficult to interpret without advanced excel skills. This presents a risk when undertaking future updates to the Carbon Calculator.
  • Minimal quality controls in place could enable gamification/errors in user outputs – there is significant variety in the methods used to obtain the input variables required for extent of drainage and water table. These variables have a significant bearing on the carbon outputs. There are no quality control mechanisms in place to ensure that the inputs entered are accurate.
  • Capacity building is required within quality control as the Carbon Calculator outputs (and the inputs and calculations which inform these) are very complicated.
  • Based on the findings in this report, certain elements of the Carbon Calculator are open to external scrutiny, particularly if decision-making on planning approval uses Carbon Calculator outputs.
  • There is a risk of fragmentation/overlap/methodological inconsistencies within the Carbon Calculator if the collaborative efforts of multistakeholder organisations that specialise in i) forestry (WCC) and ii) peat restoration (Peatland Code) are not considered.

Evaluation of Peatland Code

The IUCN Peatland Code is a voluntary certification standard for UK peatland (fens and bogs) projects seeking financial benefits from restoration activities through ‘carbon units.’ The code provides a framework for the validation and verification of greenhouse gas reductions.

The principle of the Peatland Code is classification of land use or peatland condition pre-restoration and post-restoration. In the following subsections we explore the value add of integrating this categorisation into the Carbon Calculator, focusing on bog peatland.

The Carbon Calculator does not currently fully align with the Peatland Code; there are opportunities to replicate elements of the Peatland Code within the Carbon Calculator, as well as aligning emission factors.

Overview of the Peatland Code

The Peatland Code encompasses a simplified methodology to quantify the effect of peatland restoration on land emissions, for the purpose of verification for ‘carbon units.’ The Peatland Code considers accuracy and reliability when quantifying the climatic benefits of peatland restoration. As such key requirements on projects include:

  • Validation and Verification: There is a requirement for restoration projects to undertake third-party validations and verifications to ensure climate benefits are quantifiable, additional, and permanent.
  • Management and monitoring plan: all projects are required to have a restoration management plan for the duration of the project. The monitoring plan should track the peatland condition over time.
  • Management of Permanence: to manage the risk of project permanence, a 15% risk buffer is applied to emission reduction calculations. This acknowledges the risk of future carbon losses; either from emissions associated with restoration activities (e.g. fuel use) or to future peatland restoration failure.

Bog emissions calculator

The bog emissions calculator requires four inputs (area, project duration, pre-restoration condition and post-restoration condition) (Table 6) from which emission reductions (tCO2e) are calculated from a ‘emissions lookup table’ across 100-year period (Table 7). The emission factors have been developed to align with the UK Greenhouse Gas Inventory, based on recent research from the UK Centre for Ecology & Hydrology, and the JHI (Evans et al, 2023). The difference between the pre- and post-restoration emission factors provides the carbon reductions achieved through restoration.

Table 6: Peatland Code Condition Categories (bogs)

Pre-Restoration (Baseline) Condition Category

Post-Restoration Condition Category

  • Actively Eroding: Hagg/ Gully
  • Actively Eroding: Flat Bare
  • Drained: Artificial
  • Drained: Hagg/ Gully
  • Near natural
  • Revegetated
  • Rewetted Modified Bog
  • Near natural

 

Table 7: Peatland Code Bog Emission Factors

Peatland Condition

tCO2e/ha/year

Baseline / Pre-restoration

Post-restoration

Pre-restoration

Post-restoration

Actively Eroding: Hagg/ Gully

Revegetated

17.72

3.42

Actively Eroding: Flat Bare

Revegetated

17.72

3.42

Drained: Artificial

Rewetted Modified Bog

3.32

0.32

Drained: Hagg/ Gully

Rewetted Modified Bog

2.51

0.32

Modified

Rewetted Modified Bog

2.51

0.32

Near natural

Near natural

0.32

0.32

 

Fen emissions calculator

The fens emissions calculator requires three inputs for both the pre- and post-restoration scenarios (land use classification, average annual water table depth and average peat depth) (Table 8), from which emissions from peat are calculated. Unlike the bogs emission calculator the emission factors are locked, however are understood to be a combination of Tier 1 and 2 emission factors (IPCC), and emission estimated derived from the site’s effective water table depth (Evans et al. 2021).

Table 8: Fen Land Uses

Fen Land Uses

  • Near-natural fen
  • Rewetted fen
  • Modified fen
  • Grassland (intensive)
  • Grassland (extensive)
  • Cropland

 

Benefits and drawbacks

Based on our findings of the Carbon Calculator’s technical assessment (see Section 3) and review of the Peatland Code, Table 9 provides a high-level summary of the benefits and drawbacks of integrating the Peatland Code’s methodology and emission factors within the Carbon Calculator.

Table 9: Peatland Code Summary

Benefits

Drawbacks

  • Emission factors within the peatland code have recently been updated and are aligned with the UK inventory, therefore are considered as current best practice.
  • The peatland code’s calculations include a risk buffer to account for the risk of restoration failure and additional emissions from restoration activities.
  • Restoration projects are required to have a ‘restoration management plan’ ensuring peatland condition is tracked across the project’s duration.
  • Emissions factor are not Scotland-specific.
  • The Peatland Code’s third-party verification and validation would not be applicable to users of the Carbon Calculator.
  • Through our engagement with the Peatland Expert Advisory Panel, it was determined that the full implementation of the Peatland Code on development sites would not be appropriate.

Recommendations for the Carbon Calculator

The Peatland Code provides an established methodology to quantify GHG benefits across the UK. Aligning with this methodology could improve the accuracy of baseline carbon flux and consistency in reporting the benefits of restoration activities. However, through our engagement with the Peatland Expert Advisory Panel, it was determined that the full implementation of the Peatland Code on development sites is not suitable. Further dialogue with the Peatland Code representatives is recommended to identify the optimal approach for the following opportunities for the Carbon Calculator:

  • The condition categories could be replicated to establish a more representative baseline and subsequent restoration status. The Carbon Calculator currently assumes peatland is pristine and presents a worse-case scenario in terms of carbon lost, however lost carbon may not be fairly attributed to the wind farm development.
  • Whilst the emission factors may not be wholly representative of Scotland (based on a UK average) they are widely recognised as best practice. Integration of the peatland condition categories could provide a recognised approach to quantifying the benefits of peatland restoration activities (site improvements tab).
  • Use of a risk buffer (measure of uncertainty) within the site improvements tab.
  • If building on degraded peatland, the Carbon Calculator could include a requirement on developers to improve condition of the site through the project’s lifespan. The principles of the Peatland Code could be used to inform guidance on this.

 

High Resolution Spatial Data (HRSD)

A literature review (Appendix 11.4) of eight data sources was conducted to identify HRSD measures that could indicate the presence and condition of peat. The following subsections provide analysis of the benefits and drawbacks of HRSD, and how it might improve the Carbon Calculator’s accuracy.

Summary of HRSD methodologies

To date, multiple types of imagery have been used to varying degrees of success (Table 10).

Table 10: HRSD summary of findings

#1: Optical/near infrared spectral imaging

Method

ESA’ Sentinel 2, NASA LandSat

Author

Pontone et al., 2024.

Benefits

  • Useful for gaining understanding of landcover types on the ground.
  • Free to use.

Drawbacks

  • Not successful in providing a good measure of condition.
  • Limited to 10m, distinguishing between different types of peat at this resolution is challenging.

#2: Infrared Land Surface Temperature

Method

MODIS TERRA Grid data

Author

Worrall et al. 2019

Benefits

  • Difference in land surface temperature can detect the energy balance of ecosystem, a proxy for peat health.
  • Archive data can be used to understand long term health.

Drawbacks

  • Very limited resolution of 1km sq.

#3: Synthetic Aperture Radar (SAR)

Method

Sentinel 1 VV/VH Backscatter

Author

Toca et al. 2023, Pontone et al. 2024, Lees et al. 2020

Benefits

  • Provides a proxy measurement of water table depth.
  • Archive data can be used to look at water table depth over time.
  • Free to use.

Drawbacks

  • Limited to a resolution of 22m.
  • Measurement can be affected by other variables such as inundation and vegetation compositions.

#4: InSAR

Method

Sentinel 1 Interferometry, Intermittent Small Baseline Subset method

Author

Bradley et al. 2022, Alshammari et al. 2018

Benefits

  • Detects the surface motion of peat, a direct indicator of peat health/resilience.
  • Archive data can be used to look at peat health over time.
  • Free to use.

Drawbacks

  • Limited to 90m + resolution.
  • Complex processing pipeline (which would require additional costs).

#5: LiDAR

Method

Bespoke airborne LiDAR

Author

Carless et al. 2019

Benefits

  • Useful in picking up the micro-topographic features such as drainage ditches and peat cuttings.
  • Can be mapped to a very high resolution (<1m).

Drawbacks

  • Prohibitively expensive to capture all, but a one-time snapshot given. Requires airborne imaging (e.g. drone or plane).

Summary of literature review findings

For optical based imagery (#1 and #2) cloud cover often limits the number of temporal snapshots captured, although it has not been successful in providing a good measure of condition, it can provide an understanding of landcover, including vegetation.

Active based sensing (#3, #4 and #5) can be coupled with landcover information provided from optical based imagery to provide a holistic understanding of peat condition and water table depth proxies. LiDAR data, as demonstrated by #5, is very useful for mapping topographical features such as draining channels and flow paths in high resolution but is expensive to obtain in real-time, given these features are relatively stable, LiDAR surveys commissioned over a wide area (i.e. a National Scheme) would be a useful dataset for identifying hydrological features that could inform the Carbon Calculator inputs. Our findings indicate that SAR data, coupled with the methodologies referenced in #3 and #4 appears to be the most promising in both its ability to capture hydrological condition of peat (including water depth) and the ability to obtain temporal imagery. More information on ESA’s Sentinel 1 platform is provided in Appendix 11.4. The limiting resolution of this approach may reduce the accuracy for small and/or spatially varying sites, but is advantageous over the deployment of ground-based sensors in that:

  • It provides continual mapping across the whole site, compared to a sparse deployment of specific ground-based sensors.
  • Archival data and repeated visits provide a longer temporal dataset from which to establish condition compared to ground-based sensors placed for a discrete time interval.

Future trends show a rise in popularity for SAR data products, with companies like Umbra offering high-resolution (1m) options, mitigating some of the current limitations. However, as SAR is unable provide landcover information, combining it with optical imaging could yield the most informative and accurate maps.

Although not assessed as part of this review, it is understood that Scottish Government is exploring a national LiDAR scheme with repeat collections every few years, which could track the stability, loss, and/or growth of peatlands. LiDAR alongside optical SAR and InSAR data could provide key data to inform the Carbon Calculator.

Recommendations for the Carbon Calculator

Scottish Government is exploring a national LiDAR scheme with repeat collections every few years, the results of this could be integrated into the Carbon Calculator, and reviewed to understand whether any further use of HRSD would provide additional transparency and support accuracy, over and above the following:

  • Integrating HRSD into the Carbon Calculator, through a model which combines #1, #3 & #4 HRSD types, would enable an understanding of i) land cover types, providing proxies for ii) peat condition, and iii) water table depth, as well as the provision to understand the history of prospective sites to better inform peat condition. It could therefore also be used to inform subsequent monitoring activities. The condition of peat is causally related to the emission and sequestration of carbon sequestration and since this not currently considered by the Carbon Calculator, adding this capability would provide a step change in improving the accuracy of the Carbon Calculator. The water table depth is currently considered in the Carbon Calculator but requires manual surveying. Adopting the remote sensing approach would be advantageous in providing consistent and temporal measurements that would improve the accuracy between sites and support quality control.
  • Integrating remote sensing into the Carbon Calculator will depend on having data products that are deemed accurate enough and are readily available at little or no cost. The products from TerraMotion (#4) would appear to be the most promising for peat condition but further stakeholder engagement would be needed to determine whether their offering suffices both in accuracy and cost, over and above the nationwide LiDAR scheme being explored by Scottish Government.
  • An additional piece of work could be carried out to explore a proof-of-concept data product that brings together the surface motion, water table depth and vegetation cover measures identified in the review. Combining all three types of data is likely to provide the most informative and accurate measure of presence and condition of peat. The output should be validated against a typical ground-based survey carried out by an organisation using the Carbon Calculator.

Quality Control Mechanisms

Decision makers that utilise the outputs of the Carbon Calculator include the Energy Consents Unit (ECU) and local planning authorities. ECU review applications for consent for the construction, extension and operation of electricity generating stations with capacity more than 50MW. Applications below this threshold are reviewed by the relevant local planning authority. Following engagement with ECU, it has been ascertained that the existing quality assurance processes undertaken to evaluate and support decision-making would benefit from significant enhancement. Due to the Carbon Calculator’s complexity and the skillsets required to review the data outputs, it is ascertained that the Carbon Calculator is not currently used as a decision-making tool in the capacity it was intended but is used to check the credibility of the ‘payback period.’

Recommendations for the Carbon Calculator

The following actions are recommended to improve the utility of the Carbon Calculator as a decision-making instrument:

  • The Carbon Calculator should have automated mechanisms for input variables that exceed acceptable error margins or contradict other variables.
  • A guidance document should be produced to support developers, ECU, and local planning authorities on the key drivers of peat-related carbon emissions and potential variances (i.e. carbon fluxes), this could be done through the updating of existing guidelines (i.e. Guidance on Developments on Peatland, 2017).
  • The decision to build on peatland should consider the developer’s ability to demonstrate post-installation site restoration, in line with NPF4 and Good Practice restoration Guidance (e.g. NatureScot, Peatland Code). Resilient restoration through credible restoration techniques which prioritise vegetation establishment and a return to high water tables are critical components of this. The Carbon Calculator’s purpose is to assess the carbon impact of the development on peatland. Carbon savings from site restoration should be reviewed holistically alongside a robust PMP and HMP. A review of the requirements for key EIA deliverables in terms of the inputs they require could benefit quality control and streamline the decision-making process.

A further consideration is that through the implementation of the above recommendations, Quality-controlled application data could contribute to a national database.

Carbon Calculator applicability

Based on our findings, this section explores the Carbon Calculator’s applicability as a decision-making Carbon Calculator across proposals for alternative infrastructure (e.g., transmission and distribution, battery storage options) and renewable energy development (e.g., solar) on peatland and carbon rich soils within Scotland. Whilst the Carbon Calculator, in its current form, would not be fully applicable to alternative development proposals, modifications can be made to increase transferability. Table 12Table provides some considerations against each area of the Carbon Calculator.

Table 11. RAG Ratings

RAG

Criteria


Green


Fully transferable to alternative developments


Amber


Limited modifications required to enable the Carbon Calculator to be used for other developments


Red


Area would require significant work to enable the Carbon Calculator to be used for other developments

 

Table 12: Increasing Carbon Calculator applicability (Note Section 3 recommendations apply to the below).

Areas

RAG

Potential modification/considerations

Data inputs


Amber


Data inputs would need reviewing to cover the characteristics of other renewable technologies and developments.

Payback time and CO2 emissions


Amber


Payback time may not be an appropriate measure for all asset types.

Carbon emission savings from wind farms


Amber


Minor modifications would be required to calculate back-up requirements for other renewable energy assets. For some developments (e.g. battery storage) this area may not be relevant.

Emissions due to turbine life


Red



Currently wind farm specific, however data inputs and assumptions could be modified to allow for a broader selection of assets / technologies (e.g. drop-down selection for technology option).

Loss of carbon due to back up power generation


Amber


Minor modifications would be required to calculate back-up requirements for other renewable energy assets. For some developments (e.g. battery storage) this area may not be relevant.

Loss of carbon fixing potential of peatlands


Amber


For wind turbines this area of the Carbon Calculator considers the loss of future carbon fixation through the removal of peat. As the turbines are tall and provide little shading there is minimal impact to the wider area. However, consideration would need to be given to the spatial factors of alternative technologies. For example, if solar panels shade large areas of peatland this is likely to affect the sequestration rate of bog plants. There may also be impacts to peatland carbon cycling through the heat projected into the ground. There is a need for further research to understand the full implications (NatureScot, 2022).

Loss of carbon stored within peatlands


Green


Methodologies are relevant to any development on peatland.

Loss of carbon due to leaching of DOC & POC


Green


Methodologies are relevant to any development on peatland.

Loss of carbon due to forestry loss


Green


Methodologies are relevant to any development on peatland.

Carbon saving due to improvement of peatland habitat


Green


Methodologies are relevant to any development on peatland.

Recommendations for the Carbon Calculator

In summary, although amendments would be required to the data inputs, wind turbine related emissions, and the presentation of ‘payback’ and carbon emission savings, the majority of methodologies for the peatland related calculations are relevant to any development on peatland. Whilst currently employed solely for wind farm developments, there is potential for the Carbon Calculator to be adapted to apply to grid infrastructure and other development types on peatland and carbon rich soils. There are no concerns on the Carbon Calculator’s ability to be used on projects of all sizes. However, to be applied to different infrastructure types, it is essential to consider their unique spatial characteristics, such as the shading effects and excess heat generated by solar farms. Further research and engagement are necessary to thoroughly understand how these factors impact peatland and carbon-rich soils before extending the Carbon Calculator to other development types.

Conclusion and recommendations

Conclusion

This report concludes that, based on the findings of a technical assessment, evidence review and quality control mechanisms, we recommend updating the Carbon Calculator in its current form to align with recent policy updates and advancements in science.

Our conclusions and recommendations set out how the Carbon Calculator could be updated through:

  • Section 8.2: Addressing ‘big picture’ questions regarding the Carbon Calculator’s current remit to inform future decision making.
  • Section 8.3: Making a series of updates to the current Carbon Calculator to bring it in line with scientific understanding and improve its accuracy.

Further areas of research due to evidence gaps identified during the literature review are summarised in Section 8.4.

Overarching considerations to inform future decision making

Key consideration: Does the calculator need to consider the lifecycle emissions of the wind farm, or could the focus be purely on the impact of development on peat? (Section 3.3.5)

Well-established methods and tools are available to undertake Whole Life Carbon Assessments (e.g. PAS2080). NPF4 Policy 2 (climate mitigation and adaptation) states that all proposals will be “be sited and designed to minimise lifecycle greenhouse gas emissions as far as possible.” Given this context, it is pertinent to question the necessity of the Carbon Calculator in replicating these existing approaches. Instead, it may be more beneficial to concentrate efforts on analysing the specific impacts of development on peatland/habitat carbon emissions. Key considerations include:

  • Whether the lifecycle emissions of a wind farm need to be included in the Carbon Calculator?
  • Could the calculations in the Carbon Calculator solely be focused on the impact of the development on peatland/habitat carbon emissions?
  • Is the presentation of the current payback output necessary or appropriate for decision making?

Key consideration: Is the output of the Carbon Calculator useful as a decision-making tool? (Section 3.3.3)

Since the inception of the Carbon Calculator, scientific advancements have deepened our understanding of the interplay between nature and climate change. This progress is reflected in NPF4’s mitigation hierarchy and Policy 3b, which require substantial biodiversity improvements alongside restoration and offsetting requirements. In this context, it is important to acknowledge that carbon emissions sources should be segregated and reported separately to facilitate informed decision-making.

As the UK transitions to net zero, the current carbon payback’ approach (comparing development emissions to the counterfactual of electricity generated by fossil fuels) becomes less relevant. The focus should shift to evaluating the developments on the natural environment, specifically, whether it improves the environment and sequesters CO2 effectively. This method is more insightful than balancing combined wind farm and peatland emissions against ‘carbon payback,’ which does not provide significant insights.

To better assess the carbon impact on peatland, the timeline for achieving ‘carbon payback’ or ‘carbon neutrality’ should consider land-based emissions. For example, ‘payback time’ could be defined as the period needed to restore peatland to a ‘near pristine’ condition from a reported baseline, compared to the site’s baseline emissions without development and counterfactual scenarios for non-peaty sites, considering Scotland’s widespread peatland restoration efforts (refer to Section 3.3.3 for more details).

Key consideration: Should the Carbon Calculator incorporate other land use types?

Considering the previous point, it’s important to consider whether the Carbon Calculator should be updated to account for various land use and habitat types. This would offer a more comprehensive view of the carbon impact on other land use types, as compared to the carbon impact on peatland. This aspect should be evaluated considering Scotland’s evolving Biodiversity Net Gain requirements, current PMPs, HMPs, and their anticipated updates.

Key consideration: The current quality control mechanisms are insufficient

The scope of this report was to identify the key updates or improvements which would bring the tool in line with current scientific understanding and improve the accuracy to better inform decision making. However, this report concludes that due to its complexity and skill sets required to review the data outputs, the Carbon Calculator is not currently used as a decision-making tool. Section 6 on Quality Controls provides more detail on the rationale behind this, and provides recommendations to improve the current approach, which should be considered ahead of updating the Carbon Calculator.

Key updates to bring the Carbon Calculator in line with scientific understanding and improve accuracy

Updates to the current Carbon Calculator

This report concludes that the current Carbon Calculator is no longer up to date following advancements in science, but it could be brought in line with scientific understanding and improved accuracy through the updates to the following:

3.2 Data inputs:

To improve data usability, explore options to integrate the Carbon Calculator and/or allowance for easy transfer from/to input variables that align with/can be obtained directly from other sources, i.e. Peatland Management Plan, Hydrological Assessment, HMP, and (in future) WLCA.

  • 3.3 Payback time and CO2 emissions:

Section 8.2 concludes that this area requires a significant update to accurately reflect a carbon ‘payback time’ in relation to land use emissions, and so updating the technical elements of its current calculation approach (Section 3.3.1) would not be appropriate.

  • 3.4 Wind farm CO2 emission savings, 3.5 Emissions due to turbine life and 3.6 Loss of carbon due to back up power generation:

Section 8.2 concludes that these areas of the Carbon Calculator are not required. Updating the respective technical elements of each where inaccuracies have been identified would not be appropriate.

  • 3.7 Loss of carbon fixing potential of peatlands:

To improve both scientific accuracy and data usability the baseline condition of peatland should be incorporated into the Carbon Calculator, the inclusion of the Peatland Code’s calculation methodology may make this area of the Carbon Calculator redundant (Section 3.7.3).

  • 3.8 Loss of soil CO2:
  • To significantly improve the scientific accuracy and data usability of this area:
  • Incorporate minimum and maximum parameters into the Carbon Calculator for the carbon content of dry peat and dry soil bulk density variables (Section 3.8.5).
  • Update the methodology for emissions rates from soils to reflect more recent literature and Scottish context (see Section 3.8.9 for more information).
  • Account for emissions from drainage ditches (Section 3.8.10).
  • Replace the use of averages with infrastructure specific inputs to replicate how peat is reported on in the PMP.

3.9 CO2 loss by DOC and POC loss:

To improve scientific accuracy, align DOC and POC with the 2014 IPCC Wetland Supplement, replicating the Peatland Code’s calculation methodology (Section 3.9.3).

3.10 Loss of carbon due to forestry loss:

To improve both scientific accuracy and data usability:

  • Replace the simple and detailed methodologies with one approach, informed by Woodland Carbon Code calculations (Section 3.10.5) and HRSD.
  • Remove the option to affect the wind turbine’s capacity factor via the forestry inputs tab (Section 3.10.6).

3.11 Carbon saving due to improvement of peatland habitat:

To significantly improve scientific accuracy and data usability, Update the Carbon Calculator to replicate the Peatland Code’s principles (Section 3.11.3).

5. High Resolution Spatial Data (HRSD):

HRSD has the potential to improve and enhance the data usability of the Carbon Calculator and could support quality control mechanisms. Recommendations include:

  • Consider options to integrate HRSD into the Carbon Calculator to enable an understanding of i) land cover types, providing proxies for ii) peat condition, and iii) water table depth, as well as the provision to understand the history of prospective sites to better inform peat condition, drainage variables, and subsequent monitoring activities. This could act as a quality control measure against inputted variables.
  • Further engagement with JHI and other key stakeholders involved in HRSD within Scotland (i.e. Nature Scot, CivTech) is recommended to enable a joined-up and effective approach to the solution developed.

Further research

This review has identified the following evidence gaps that necessitate further research and/or engagement:

  • Further research is required to understand the impacts of climate change on the carbon fixing potential of peatlands.
  • Further research is required to understand whether the option to reuse peat elsewhere would be appropriate.
  • Further research required into the link between peatland condition and bog plant fixing potential, or on updated fixation emission factor rates (if appropriate).
  • Further research is required to identify a suitable ‘average extent of drainage.’
  • Further research is required to provide more specific DOC and POC estimations.
  • Further research is required to understand whether HRSD could inform the carbon content of dry peat and dry soil bulk density variables.
  • Further research on the impact on peatland from the removal of trees (where located on peatland and other carbon rich soils).
  • Further research is necessary to understand how the spatial variability of different development types could impact peatland and carbon-rich soils.

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Appendices

The following appendices open a download link to each of the spreadsheets.

Appendix 1 Technical assessment (opens spreadsheet)

Appendix 2 Sensitivity Analysis (opens spreadsheet)

Appendix 3 – High Resolution Spatial Data (HRSD) Assessment (opens spreadsheet)

© The University of Edinburgh, 2025
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  1. Avoid – by removing the impact at the outset, Minimise – by reducing the impact, Restore – by repairing damaged habitats, Offset – by compensating for residual impact that remains, with preference to on-site over off-site measures.


The Scottish Government’s Climate Change Plan Update sets out an ambition for the agriculture sector to reduce emissions by 31% from 2019 levels by 2032. It also sets a commitment to “work with the agriculture and science sectors regarding the feasibility and development of a SMART target for reducing Scotland’s emissions from nitrogen (N) fertiliser.”

The agricultural sector is dependent on N inputs, both organic and inorganic. The inefficient use of these inputs creates N wastage, impacting air and water quality and the climate.

The global nature of the issue provides an opportunity for Scottish agriculture to learn from other countries on how to improve Nitrogen Use Efficiency (NUE), i.e. taking action to reduce agricultural N losses while maintaining and supporting the sector in terms of income and yield.

This report explores the potential for setting a NUE target for agriculture in Scotland. It examines N flows found in Scottish agriculture as shown in the Scottish Nitrogen Balance Sheet (SNBS). It provided a clear analysis of the opportunities and barriers.

Conclusions

While this research identified opportunities for setting a NUE target for Scottish agriculture, more work is needed to fully understand the following elements:

  • differential flows for each sector
  • make appropriate changes to the SNBS
  • ensure that the role of legumes in emissions reduction is fully integrated and
  • carefully plan communication to achieve support from the farming sector.

A NUE target is not currently the most appropriate option for Scotland, the report concludes. This is partially due to the methodology in the current SNBS.

For further information on the findings, barriers and opportunities, please download the report.

If you require the report in an alternative format, such as a Word document, please contact info@climatexchange.org.uk or 0131 651 4783.

Research completed March 2024

DOI: http://dx.doi.org/10.7488/era/5316

Executive summary

Background

The Scottish Government’s Climate Change Plan Update (CCPu) sets out an ambition for the agriculture sector to reduce emissions by 31% from 2019 levels by 2032, and a commitment to “work with the agriculture and science sectors regarding the feasibility and development of a SMART target for reducing Scotland’s emissions from nitrogen (N) fertiliser.”

The agricultural sector is dependent on N inputs, both organic and inorganic. The inefficient use of these inputs creates N wastage, impacting air and water quality and the climate. The global nature of the issue provides an opportunity for Scottish agriculture to learn from other countries on how to improve Nitrogen Use Efficiency (NUE), i.e. taking action to reduce agricultural N losses while maintaining and supporting the sector in terms of income and yield.

This report explores the potential for setting a NUE target for agriculture in Scotland. It examines N flows found in Scottish agriculture as shown in the Scottish Nitrogen Balance Sheet (SNBS), providing a clear analysis of the opportunities and barriers.

Key findings

Whilst there is theoretical potential for setting a NUE target for Scotland, there are practical obstacles that policy makers would need to overcome for the target to be implemented.

This research argues sector specific NUE values are not currently feasible due to the calculation set-up in the SNBS and the assumption that production will remain stable, with only inputs decreasing.

  • We suggest that the SNBS calculations need refinement to attribute flows of N to the different measures and sectors. In the current version of the SNBS, the NUE calculations do not align directly with what happens in practice because there are overlaps and movements of N flows between the different agricultural sectors.
  • These are not easily viewed in isolation and not necessarily attributed to the correct sector. For example, mitigation measures around manure management will, in practice, be mainly implemented by the livestock sector but will, in the current calculations, be attributed to the arable sector because they are linked to reduced emissions from spreading of organic matter to soils.

Opportunities

  • The SNBS would offer an effective data source for setting and monitoring progress towards a single nationwide NUE target that covers all sectors.
  • Many mitigation measures with known impacts on reducing N waste and improving N use are already in use in Scotland. Measures with the greatest potential improvement on NUE are
  • nitrification inhibitors
  • improving livestock nutrition, and
  • improving livestock health.
  • Note – that the improvement reflects implementing the relevant measure individually and does not consider any combination effects or interactions with other measures.
  • The lowering of N-related emissions through reaching a NUE target will positively contribute to other emission reduction targets and the potential for an increase in farm business profitability.

Barriers

  • Since a sector specific NUE target is currently not feasible, the remaining option is a single nationwide target.
  • However, the arable, horticultural and livestock sectors would need to implement distinct mitigation measures, start from differing baselines, and will react inconsistently to implemented changes. This is partially due to the current limitations in the SNBS, but also due to the much lower baseline of current NUE values, setting a nationwide NUE target might cause the livestock sector to feel unfairly targeted.
  • Some mitigation measures require significant capital expenditure to implement.
  • The concept of NUE is complex and clear communication is required to ensure that targets and measures are clearly understandable and achievable to generate support from the farming sector.
  • We examined different scenarios to model a potential target. The table below shows an achievable target and one that is more ambitious. The 2045 (Ambitious) scenario is based on transformational change across the sector.
 

Potentially achievable NUE estimates (%)

2021 (Current)

2030

2040

2045

2045 (Ambitious)

Whole agriculture

27.2

33.7

35.7

38.2

40.9

  • No country currently uses a standalone NUE target. Several countries have set N-related targets, some of which include information on NUE. Notably, the Colombo Declaration represents the first time that governments are collaborating on a global N management target on N waste.

Conclusions and recommendations

While this research identified opportunities for setting a NUE target for Scottish agriculture, more work is needed to fully understand the following elements:

  • differential flows for each sector
  • make appropriate changes to the SNBS
  • ensure that the role of legumes in emissions reduction is fully integrated and
  • carefully plan communication to achieve support from the farming sector.

A NUE target is not currently the most appropriate option for Scotland. This is partially due to the methodology in the current SNBS.

Recommendations

  • Explore the potential for a more granular breakdown, and accurate representation of N flows in the SNBS. This may be difficult but would significantly help both monitoring and setting of a SMART NUE target.
  • Creating a NUE target requires considering several criteria including mitigation measures, current uptake, applicability, expected future uptake, timescales, and sector breakdown. It is important to understand that other agricultural practices may impact N flows, as will changes in the size of agricultural sectors, and achieving these targets in practice will require supporting instruments to encourage the uptake of these measures. This research recommends that:
  • N waste be considered as a target instead of a NUE target and that a SMART analysis is carried out to explore a N waste target further. Opportunities for setting a N waste reduction target include:
  • It is an easier concept to communicate to the farming community.
  • It values any N as a resource until it is lost as waste, creating options for greater collaboration between the arable, horticulture and livestock sectors. Any potential bias towards a sector will be avoided.
  • A N waste target would achieve reductions in national NUE thereby achieving the same objectives without the current issues around NUE targets.
  • Experience of the United Nations Environment Assembly and the Green Deal’s Farm to Fork targets has shown more potential in successfully reducing N pollution when focusing on reducing N waste over NUE targets as a policy option.
  • If a decision is made to set a NUE target, the underlying assumptions should first be updated based on latest available evidence, for example using the updated Up to date Farm Census data. would strengthen any underlying assumptions and may directly influence the potential for the mitigation measures, particularly relating to slurry and manure management.
  • The SNBS be improved by assigning distinct N flows to N waste and N re-use. A SMART target analysis for N waste will be beneficial to set a challenging and realistic target.

Glossary / Abbreviations table

Table 1: Glossary/ abbreviations table

Term/acronym

Definition

CCPu

Climate Change Plan Update

CO2

Carbon Dioxide

EUNEP

European Union Nitrogen Experts Panel

GHG

Greenhouse gas

INMS

International Nitrogen Management System

kt N / yr

kilo tonnes of nitrogen per year

MtCO2e

Million tonnes of carbon dioxide equivalent

N

Nitrogen

N2

Di-nitrogen

NH3

Ammonia

NH4+

Ammonium

NO3

Nitrate

N2O

Nitrous Oxide

NUE

Nitrogen Use Efficiency

NVZ

Nitrate Vulnerable Zones

PESTLE

Political, Economic, Social, Technical, Legal, Environmental

REA

Rapid Evidence Assessment

SNBS

Scottish Nitrogen Balance Sheet

SWOT

Strengths, Weaknesses, Opportunities, Threats

UNEP

United Nations Environment Program

Introduction

Nitrogen and its relevance to agriculture

Crops require nitrogen (N) to maximise growth. Most crops take up N from the soil in the form of nitrate (NO3-). NO3– in soils come from three major sources, the application of organic livestock manures, the application of inorganic N fertilisers and nitrogen fixing plants such as legumes. During harvest and through grazing, N is removed from the system. N can also be lost from soil through NO3– leaching and through emissions of ammonia (NH3) and nitrous oxide (N2O). The N cycle (Figure 1) shows how different forms of N flow through the agricultural system.

Figure 1: The Nitrogen Cycle

An excess of N can both directly and indirectly lead to soil, water and air quality deterioration which is detrimental to human and ecosystem health (e.g., affecting respiratory systems and reducing oxygen in water). According to the IPCC AR5 Synthesis Report, N2O has a global warming potential (GWP) 273 times that of carbon dioxide (CO2) over a 100-year timescale. In Scotland N2O is responsible for a quarter of the agriculture sector’s total GHG emissions.

More detail can be found in Appendix A on the process of leaching, the effects of eutrophication and how N2O and NH3 are emitted from agricultural sources and in Appendix B on the chemical processes of N conversion.

Nitrogen Use Efficiency

Nitrogen use efficiency (NUE) describes the ratio between total N input (e.g., fertiliser) and total N output (e.g., harvested product) expressed as a percentage (%). Figure 2 presents a visual example of NUE.

Figure 2. NUE diagram. Source: Udvardi et al., 2021

NUE gives an indication of the efficiency of crop utilisation of N. Generally, the higher the percentage NUE the better as this means less loss of N to air and water and indicates the crop is efficient in the uptake of N. However, pushing the ratio too high (for example over 90% in a cereal crop) can indicate ‘soil nutrient mining’ leaving not enough available N to maintain healthy crop growth and soil ecosystems (Sanchez, 2002). When NUE is too low (less than 50% in cereal crops), a large amount of N is likely being lost to the water and air. An ideal NUE would therefore be between 50% and 90%. NUE efficiency is also greatly impacted by climatic conditions, with changes in microbial activity in drought and frozen soils, along with increased risk of denitrification or leaching when soils are waterlogged.

NUE values are therefore both indicators of resource efficiency and markers for improvement. Key factors influencing NUE include crop type and rotation, soil pH and texture, climate, ammonia, leaching, biological utilisation of N and N management amongst others. As such, an absolute NUE reference value cannot be universally applied and will need to be understood and optimised for specific systems.

Nitrogen and NUE targets in other countries

Introduction

A Rapid Evidence Assessment (REA) seeking evidence relating to the setting and use of nitrogen and NUE targets was undertaken and identified peer-reviewed academic literature as well as government policies and websites. The review also identified grey literature sources such as farming and industry press reports. This search included, but was not limited to, targets for NUE, N emissions and N fertiliser use. The methodology can be found in Appendix C. The review focussed on identifying:

  • Relevant scientific research on NUE target setting (4.2)
  • Countries with N-related target/s, including types, values and timeframes (4.3)
  • Relevance to Scottish agriculture, agricultural sectors and N flows (4.4).

Research on NUE target setting

This section includes information found through the REA on global NUE trends and relevant scientific research on the possibility of setting a NUE target including the necessary considerations (e.g., differences in farming sectors). 95 sources of literature were reviewed through the REA, 38 of which were from the UK, 32 from European countries and the remaining from other countries from around the world. Search strings used to gather this data can be found in Appendix C.

The NUE trend in the UK shows an increase from 1961 to 2014 (Lassaletta, L et al., 2014) which is likely a response to both regulation and market forces (for example the Nitrates Directive and changes in farm incomes). A full list of country-specific changes (%) in NUE values from 1961 to 2014 can be found in Appendix D. Following on from these observations, the research discussed below highlights the requirements and considerations for setting a NUE target.

Studies such as Quemada et al., 2020 collected farm-level data from 1240 farms across Europe and through statistical analysis, present NUE targets for different agricultural systems (e.g., 23% for a pig farm and 61% for an arable farm) which demonstrates the possibility of setting farm-level NUE targets. However, the study also highlights the importance of how differences in farming sectors will impact target setting.

A study conducted by Antille et al., 2021 states that there is no universal method for the calculation and reporting of NUE across all agricultural sectors. Furthermore, research projects which provide recommendations for NUE targets also suggest that such targets could be dependent on the agricultural system and its management, as well taking the ‘4R nutrient stewardship’ approach (right fertilizer type, right amount, right placement and right time) (Waqas et al., 2023). These approaches are country and region specific, dependent on climate, farmer knowledge, technological advancement and availability.

The EU Nitrogen Experts Panel (EUNEP) (initiated by an industry-based organisation ‘Fertilizers Europe’) recommends a maximum NUE of 90% (Duncombe, 2021), with an ‘ideal range’ of 50% to 90%. This range has been set to reflect that a NUE value below 50% is likely to result in N lost to the environment, while a value above 90% could result in soil N mining. Further detail is given in section 3.2. Whilst it is important to note that values will vary according to context (soil, climate, crop etc), the identification of this ‘ideal range’ by the EUNEP helps us to understand the opportunity and potential for setting a NUE target.

The research has highlighted that whilst it is possible to set NUE targets, there are a number of variables which impact upon setting a NUE target. These variables include the differences in farming sectors, differences in farming management, a lack of universal calculation and reporting of NUE, country / region specificity and climate.

 

N targets by country – types and policy context

There are currently no standalone country level NUE targets. Several countries, however, have set N targets through various means, some of which include information or actions on NUE. The review of approaches and literature can be summarised as having three main reasons/drivers for introducing N targets, these are all focused on responding to environment and climate impacts of N emissions:

  • To lower GHG emissions
  • To improve water quality
  • To improve air quality

The underlying impact of N-related targets all seek to reduce N waste[1], however, the two primary mechanisms differ in their points of measurement. Some targets are set to reduce N emissions whilst others are set to improved water or air quality. Table 2 gives an overview of existing initiatives across the world and their main N target with relation to agriculture. Many are relatively vague and reflect the difficulty in setting firm policy across regions or countries. No set value was found for the targets in table 2 that do not include a percentage or numeric change. These initiatives or legislation are described in further detail below.

Table 2. Overview of existing initiatives on N targets.

Initiatives and country

N target

Colombo Declaration 2019, United Nations Environment Programme

Halve N waste by 2030

Climate Change Response (Zero Carbon) Amendment Act 2019, New Zealand

Reduce N2O emissions to net zero by 2050

Nitrates Directive 1991, EU

Reduce NO3 losses from agricultural sources

National Emissions reduction Commitments Directive 2016, EU

Reduce NH3 emissions from agriculture

Farm to Fork Strategy 2020, EU

Reduce nutrient losses by at least 50%

Harmony rules, Denmark

Limit N inputs to land from livestock manure

Climate Action Plan 2021, Ireland

Improve NUE

Green transition of the agricultural sector 2021, Denmark

Reduction of N emissions by 10,800 tonnes by 2027

French Climate and Resilience Law 2021, France

Reduction of N2O emissions by 15% of 2015 levels and NH3 emissions by 13% of 2005 levels by 2030

National Emissions Ceilings Regulations 2018, UK

Reduction commitments for NH3 of 16% by 2030 relative to 2005 levels

Wales, UK

Reduction of agricultural GHG emissions by 28% by 2030 compared to 1990

International action

The UN Environment Program (UNEP) previously considered ‘an aspirational goal for a 20% relative improvement in full-chain NUE by 2020’ (Sutton et al., 2014). However, Sutton et al., (2021) found that this could lead to an unfair distribution of effort whereby everyone had to increase their NUE by a relative amount. If this was the case a farm currently operating with high efficiency, e.g., 60% NUE, would have to increase by 12% to reach this 20% target. Whereas a farm operating with low efficiency e.g., 10% NUE, would have to increase by 2% to reach the same 20% target.

To overcome this unfair distribution, a target to halve N waste was seen as a more equitable approach as less waste means less action is needed. For example, to reduce N waste by 50%, a farm with higher N waste e.g., 100t N/yr would have to reduce by 50 t N/yr and a farm with less N waste e.g., 10 t N/yr would have to reduce by 5t N/yr. Therefore, the largest effort needed is placed on farms with higher N waste (low NUE) as opposed to farms already operating with high efficiency (high NUE).

Alongside the support from the UNEP and the technical support of the International Nitrogen Management System (INMS), the Colombo Declaration represents the first-time that governments are collaborating on an ambitious, quantitative, and global N management target by seeking to cut N waste by 50% across the world.

Outside Europe

New Zealand’s Climate Change Response (Zero Carbon) Amendment Act 2019 includes a target to reduce N2O emissions to net zero by 2050. Canada (which has set a target to reduce fertiliser emissions by 30% by 2030) applies a region-specific approach due to the vast expanse of the country having variable meteorological conditions.

The European Union

The Nitrates Directive (1991) aims to protect water quality across Europe by preventing nitrate losses from agricultural sources through the promotion of good farming practices and includes limitations on N application from manures. Nitrate Vulnerable Zones (NVZs) are areas where the water bodies, such as lakes or rivers, are considered ‘at risk’ because there they have more than 50 mg/l of NO3 or are eutrophic. Farmers in these areas must comply with rules set out in the Member States’s action programmes to reduce the risk and the Managing Authorities need to report on NO3 concentrations in ground and surface waters. The Directive does not focus on N emissions other than NO3. While the Nitrates Directive has driven a reduction in nutrient application over the last 30 years, targets have failed to improve NUE in many areas with reported high levels of N surplus (N remaining beyond plant and soil requirements) found in the Netherlands, Belgium, north-west Germany, Luxembourg and Brittany in France.

The National Emissions reduction Commitment (NEC) Directive (2016) is the current primary European regulation requiring actions to improve air quality and sets targets for reduction in the emissions of key air pollutants. This is important in an agricultural context due to the inclusion of setting reduction targets for NH3. Target reductions are specific to each Member State and vary significantly with the target NH3 reduction for 2030 ranging from 1% for Estonia and 32% for Hungary.

The European Green Deal (2019) is the EU’s holistic plan to achieve net zero GHG emissions across the EU, while improving biodiversity and human health. The Farm to Fork strategy (2020) includes targets to reduce the use of N fertilisers and losses of N to the environment to support improvements in air and water quality and to reduce emissions of GHGs. The strategy sets a target to reduce nutrient losses by at least 50%, while ensuring that there is no deterioration in soil fertility. The European Commission expect this to reduce the use of fertilisers by at least 20% by 2030.

Considering the European wide scope of the directives and strategies to reduce N pollution, our study findings were surprising in that examples of nationwide NUE targets are limited. Whilst no country has a standalone NUE target, some countries such as Ireland and Denmark have incorporated NUE as an ‘action’ as part of a programme or another target (e.g., GHG target).

The Danish example relates to the historic, 1980 ‘Good Agricultural Practice Program’ where increasing NUE was part of a suite of actions to reduce N use. This program was unsuccessful in limiting emission effects and as such ‘harmony rules’ were introduced, which, along with other measures, increased the Danish national NUE to an average of 40%. The Danish harmony rules prescribe the minimum area that a livestock farm must have for spreading livestock manure from their livestock production, thus limiting N inputs to land from livestock manure (Sommer and Knudsen., 2021).

Ireland’s Climate Action Plan 2021 put forward a suite of actions to deliver their GHG target that includes N. Action 359 details the implementation of ‘a suite of measures to improve NUE’. Teagasc, who is leading this action, sees that there is room for improvement across Irish dairy farms with an industry target of 35% NUE “set for farmers to achieve in the coming years” – an improvement of 10% from the current NUE of 25%.

Also in 2021, Denmark introduced the ‘Green transition of Danish agriculture’ which has set an agricultural target to reduce GHG emissions by 55-60% by 2030, including a reduction of N emissions by 10,800 tonnes by 2027. The specific impacts on the aquatic environment are further covered through their Action Plan on the Aquatic Environment III which has targets to reduce N leaching.

France, through the French Climate and Resilience Law 2021, have set targets for reduction of N2O emissions by 15% of 2015 levels and NH3 emissions by 13% of 2005 levels by 2030 (Hawley., 2022). This law includes measures to reduce the use of mineral N fertilisers.

The United Kingdom

In the UK, there are N relevant targets at both UK-wide and devolved levels. Nitrate vulnerable zones (NVZ), designated as part of the Nitrates Directive (1991), aim to reduce nitrate water pollution by encouraging good farming practice. Areas where the concentration of nitrate in water exceed 50 mg/l in ground and/or surface waters have been designated as NVZs. There are at least 70 NVZs in England and Wales, covering 55% of agricultural land in England and 2.3% of Wales. Five areas of Scotland (Lower Nithsdale, Lothian and Borders, Strathmore and Fife (including Finavon), Moray, Aberdeenshire / Banff and Buchan, and Stranraer Lowlands) have been designated as NVZs.

The National Emissions Ceilings Regulations (NECR) (2018) commits the UK to reduce NH3 of 8% by 2020 and 16% by 2030, both relative to 2005 levels. The 2020 target was not met, but there has been a 12% reduction since 2005[2]. The NECR also contains reduction targets for nitrogen oxides (NOx), of 55% by 2020 (which was met) and 73% by 2030 but agriculture is a less important source.

Wales have set a target of reducing its total agriculture specific GHG emissions by 28% by 2030 compared to 1990. There are currently no UK-wide agriculture specific GHG emissions reduction targets, however, there is a UK-wide target of net zero by 2050, and agriculture will play an important role in achieving this target. For example, Defra has implemented new regulations on the use of urea fertilisers from 2023, which means that only urease-inhibitor treated or protected urea fertilisers may be used throughout the year, while untreated/unprotected urea fertilisers may only to be used from 15th January to 31st March each year. This regulation is expected to deliver an 11kt reduction in ammonia emissions by 2024/2025.

Why set a NUE target in Scotland?

It is important to consider the size and balance of the different Scottish agricultural sectors to understand the NUE potential of each sector. This section provides detail on the different forms of N found in Scottish agriculture, their impact on flows of N and how they can be targeted to improve NUE. A list of mitigation measures to improve NUE can be found in Appendix E and the impacts of these measures on NUE in Scotland are discussed in section 6.2.

The most recent Scottish GHG Statistics (2021) states that 2MtCO2e of N2O was emitted from the agricultural sector, which is a quarter of Scotland’s agriculture sector’s total GHG emissions and 2/3rds of total N2O emissions. N2O is emitted from soils after the application of N-fertilisers and manures (Brown, 2021). In addition, 90% of Scotland’s total NH3 emissions are attributed to the agricultural sector. Tackling the emissions of these pollutants will directly contribute to the following Scottish Government policies and ambitions:

Understanding N flows in Scotland

In recognition of the potential for reducing N to reduce total GHG emissions, the Climate Change (Emissions Reduction Targets) (Scotland) Act 2019 set requirements for Scottish Ministers to create a Scottish Nitrogen Balance Sheet (SNBS) from 2022 (Figure 3). The N flows in the SNBS combine data across all sectors of the economy and environment forming an evidence base to support the optimal use of N across all economic sectors to achieve optimal economic and environmental outcomes. While the SNBS was published in 2022, the data within it relates to 2019. Scotland is currently the only country to have planned to regularly update a cross-economy and cross-environment N balance sheet.

Figure 3. Scottish Nitrogen Balance Sheet (baseline data (mainly 2019)). Source: 3. Results from the initial version of the Scottish Nitrogen Balance Sheet – Establishing a Scottish Nitrogen Balance Sheet – gov.scot (www.gov.scot)

The annual SNBS report to the Scottish Parliament presents an assessment of:

  • progress towards implementing proposals and policies relevant to improving NUE in Scotland,
  • any future opportunities for improving NUE in Scotland, and
  • how NUE is expected to contribute to the achievement of future emissions reduction targets (as per section 98 of the Climate Change (Emissions Reduction Targets) (Scotland) Act 2019)

In 2022, the SNBS report published NUE values for agriculture as a whole sector (27%) with more granular figures of 65% for crop production NUE and 10% for livestock feed conversion. This valuable baseline shows NUE’s potential for improvement which can reduce emissions from all forms of N to support improvements in air and water quality with positive implications to both human (Pozzer et al., 2017) and biodiversity health (Houlton et al., 2019). While the SNBS is a valuable baseline for improving N management it is important to note the specificities of its set-up particularly on how different quantities of N are attributed to different sectors and how this relates to what happens in practice (more detail on this can be found in Section 6.5).

Research has found that the global arable NUE is 35%. When we do not consider all the variables which impact NUE and NUE target setting, as discussed in sections 3.2 and 4.2, the Scottish arable NUE of 65% appears to compare well to international data, however, some EU countries have arable NUEs of up to 77%, showing there may be room for improvement. The 2022 SNBS report states total N losses from agriculture to the environment amount to 30.2 kt N/yr as air pollutants (NH3, nitrogen dioxide (NO2) and N2O) and 104 kt N/yr from runoff and leaching from agricultural soils.

Targeting different forms of N

Figure 4 Scottish agricultural sectors (Scottish Agricultural Census June 2021)

The different N inputs and outputs of Scottish agriculture are described below (also see Figure 3). Most of Scotland’s 5.64 million ha of agricultural area is best suited to livestock farming with a significant proportion occupied by cattle and sheep in Less Favoured Areas (LFAs) (55% or 3,159,137 ha) followed by crops and grass (1,885,701 ha), shown in Figure 4. Non-LFA cattle and sheep (107,712 ha) and specialist dairy (106,935 ha) are large sources of N in manure. More intensive sectors such as pigs and poultry do not have a direct correlation between NUE and land area, however they are significant sources of manures and contribute to N inputs. These areas are used to track N flows from the SNBS against sectors of particular potential in section 4.4.2. Note that forestry and aquaculture are out of scope of this project but will have impacts on Scottish N flows.

NUE varies between different Scottish farm types as the biological utilisation of N influences the potential NUE. The SNBS shows that livestock farms currently have a lower NUE (10%) than arable farms (65%). This is partly due to the relative inefficiency in the conversion of ingested N in feed converting to stable N within livestock products (milk and meat).

N Inputs

Fertiliser as the N input

The SNBS details that one of the largest flows of N in Scotland (143.8 kt N/y) is the use of inorganic fertiliser on arable crops and grass, with 62.1kt of this inorganic N applied to crops per year and 81.7kt going to grass [4]. The British Survey of Fertiliser practice states that in 2022, 63 kg N/ha were applied on average to all crops and grass in Scotland.

There is little information on N use in Scottish horticulture and permanent crops. Nonetheless, N fertiliser recommendations for vegetables, minority arable crops, bulbs, soft fruit and rhubarb crops exist. The high value of many of these crops and the technological advances taking place in this sector facilitate a higher degree of precision in management (e.g., GPS use for N application, leaf N monitoring, fertiliser application within irrigation water etc), which allows a better understanding of N flows in these systems. Targeted N applications could lead to reductions in inputs and waste thereby improving overall NUE for these crops. However, to date there are no recommended NUE levels for these specialist crops, thus more research is needed to understand the impact of reduced N applications on crop health and yield.

The evidence relating to the N requirements for the majority of crop and grass areas in Scotland is well described within the technical notes, and recommendations for NUE targets could build upon the evidence supporting these recommendations. Like specialist crops, improvements in fertiliser practices and technology can support improvements in N applications which will help matching of N inputs to crop requirements with greater precision and thus improves NUE.

Livestock Feed intake as the N input

The optimum levels for dietary crude protein are often exceeded to ensure that N intake does not limit either growth or welfare. This excess of N supply in the diet results in surplus N being excreted through manure and urine leading to N losses. Cattle cannot efficiently convert dietary N (efficiency ranging between 22-33%) and therefore, on average, 75% of consumed N is wasted, mainly through excretion. Matching N supply in feed with livestock requirements is part of ‘precision livestock feeding’ which can increase farm profitability, reduce emission intensity of methane (Rooke et al., 2016) and reduce N intake and excretion. Reductions to NH3 and N2O emissions from livestock sources due to precision feeding vary widely. However, studies have found that a reduction in crude protein of 2% leads to a 24% reduction in NH3 emissions in broilers, and a 1% crude protein reduction in pig feed results in a 10% reduction in NH3 emissions (Santonja, 2017).

The SNBS found one of the largest N flows is N excreted by livestock (142.9 kt N/y). The control of N levels added to soil from livestock directly impacts the input part of the livestock NUE calculation. A NUE target aimed at the livestock sector may be most impactful as it currently has the lowest NUE (10%) whilst also covering the largest amount of agricultural land (combined total of 3.3 million ha) meaning even a small, targeted improvement in NUE for livestock could have a significant impact on the overall N budget.

N Outputs

Ammonia as the output

NH3 from agricultural sources produces particulate matter which can impact human health, causing diseases such as cardiovascular and respiratory disease. In addition, NH3 emissions can result in the long-range transport of N compounds and this N deposition can cause acidification and eutrophication. Scottish agriculture accounts for 90% of total NH3 emissions, which have decreased by 12% over the last 30 years. NH3 is tied specifically to the (housed) livestock sector, with most emissions (35% of NH3 emissions) coming from cattle manure management. Livestock housing and storage of manure is responsible for 10.5kt N/y in the form of NH3 emissions, therefore improvements targeted at this sector would directly improve NUE. Examples of mitigation measures which can be introduced to lower the NH3 emissions in this sector are detailed in Table 3 under section 6.2.1 and include slurry store covers and slurry acidification.

Use of urea based inorganic fertilisers can lead to significant losses of NH3. High temperatures and winds at the time of fertiliser application or very dry conditions can lead to high levels of NH3 volatilisation (the conversion of NH4+ to NH3 gas) with a significant proportion of the N being lost and unavailable to the plants. A useful mitigation measure is the use of urease inhibitors with urea fertilisers to reduce these emissions.

Nitrate leaching as the output

Excessive leaching of N from agricultural activity can lead to water pollution and eutrophication which can then result in the loss of aquatic biodiversity and GHG emissions. The SNBS shows N run-off and leaching from crops and arable land as 45.5 kt N/yr and from grass as 58.5 kt N/yr. This N is lost as NO3, which is readily mobile in soil water or runoff. Any N that is lost from the soil is no longer available to plants thereby lowering the potential NUE and increasing agricultural pollution.

According to Adaptation Scotland, Scotland is predicted to experience an increase in rainfall, with intense, heavy rainfall events increasing in both winter and summer. This has the potential to increase N leaching as soil moisture controls both crop N uptake and N leaching (McKay Fletcher et al., 2022). In addition, Scotland’s topography affects the rate of run-off as steep slopes promote surface run-off. When considering Scotland’s topography and the predicted change in rainfall, the potential for leaching will increase and continue to negatively affect water quality. Those areas currently most at risk are classified as NVZs.

Nitrous oxide emissions as the output

N2O is a GHG that accumulates in the atmosphere and directly contributes to climate change. The SNBS shows 5.9kt N2O per year is emitted from the agriculture sector. This includes 0.9kt from livestock (including manure management), 3.8kt from soil management (including mineral fertiliser use), and 1.2kt of indirect emissions (from N deposition and NO3 leaching). N2O is produced in the process of denitrification, where denitrifying bacteria under conditions where oxygen is limited (for example waterlogged soils) use the NO3 available in soil. By using the NO3in soil, these bacteria reduce the NO3 available by plants potentially negatively impacting yield. In conditions where NO3 is available in excess denitrification can reduce NO3 losses through leaching. However, since N2O is produced in the process, negative impacts on climate are the result. Total elimination of N2O emissions from agriculture is not possible; however, some mitigation is possible through improvements in soil conditions and avoidance of N fertiliser application under wet conditions (Munch and Velthof, 2007).

Crop and livestock outputs

Crop and livestock products are the useful outputs of N from agriculture. In Scotland these account for 54.5kt N per year. This value includes livestock products, including meat, milk, eggs, and wool, and harvested crops used for food for human consumption (but excludes crops for animal feed or fodder). Useful crop outputs also include seed, feed and straw, but these are retained in the agricultural system and so are not final outputs.

Cereals, explicitly for alcohol production, accounts for the largest useful output flow in Scotland at 20.5kt N, followed by livestock products at 19.6kt N and crop product for human consumption at 12.2kt N (all values per year).

Optimising the quantity of N recovered in these outputs i.e. the N is taken up by the plant or animal and used to increase growth, relative to the quantity of inputs (feed and fertiliser) is key to reducing N waste and improving NUE. Managing the quantity of N application to meet crop and livestock requirements alongside the soil conditions will improve the overall NUE.

Viability of a SMART Target for NUE in Scotland

This section looks at the viability of setting a NUE target for Scotland and provides a summary of the risks and benefits of setting a Specific, Measurable, Achievable, Relevant, and Time-Bound (SMART) NUE target in Scotland and presents how a range of influences can support or hinder the achievement of a NUE target. Information on N targets in other countries was considered and analysed for their applicability to Scotland. Since no other country has a standalone NUE target, we had to rely on information on other N targets for our analysis and transfer these finding to a NUE target for Scotland. The methodology can be found in Appendix F.

Analysis Tools

SWOT analysis

Strengths, weaknesses, opportunities, and threats (SWOT) of setting N-related targets were analysed based on the information gathered on N targets in other countries. We also included analysis of GHG and climate related targets where relevant to increase the body of information. This information was then used to assess applicability of setting a NUE target for Scottish agriculture with the limitation that the analysis was based on N, GHG and climate related, rather than NUE specific targets. The SWOT analysis shows a range of influences which can support or hinder the achievement of a NUE target. The full SWOT analysis can be found in Appendix F.

PESTLE analysis

Setting NUE and other N targets are subject to a range of enablers and barriers. Therefore, a political, economic, social, technical, legal, and environmental (PESTLE) analysis was undertaken to assess the feasibility of setting a NUE target for Scottish agriculture, again, with the limitation that the analysis was based on N, GHG and climate related rather than NUE specific targets. The PESTLE assessment took place following the SWOT analysis to ensure the findings from the SWOT were assessed and, if relevant, included into the PESTLE categories. The full PESTLE analysis can be found in Appendix F.

Discussion

Supporting a SMART NUE target

The SNBS is reviewed and updated annually and provides a source of data for measuring and monitoring the changes in NUE and thus the progression of a NUE target. In addition, all mitigation measures identified in section 6.2 and analysed for their effect on Scottish agriculture NUE are captured by the SNBS. The use of the SNBS enables a measurable target. This was identified as a strength and technical enabler in the analysis of setting a NUE target.

Another strength and technical enabler identified through the analysis includes the mitigation measures required to achieve a NUE target. N-related mitigation measures are well understood, and many are relatively low cost and already practiced in Scottish agriculture (e.g., use of catch and cover crops) which makes reduction in N losses achievable. Furthermore, measures continue to be developed through additional research e.g. in Canada to understand the emission reduction potential, costs and benefits of different measures at farm level.

Section 6.4 recommends years 2030, 2040 and 2045 as deadlines which would ensure a NUE target is time-bound. These years align with other emission targets set in Scottish Government which may affect agriculture and therefore complement a new, potential NUE target. Including three timed steps into a binding target would also help measure the progression of the NUE target whilst also encouraging the delivery of high reductions.

A NUE target would be relevant in meeting statutory emission reduction targets. Introducing a NUE target would lower N-related emissions and would therefore contribute to other emissions reduction targets, for example the CCPu which aims to reduce agricultural GHG emissions by 31% from 2019 levels by 2032. Similarly, a NUE target would be relevant to several other environmental issues as the implementation and success of a NUE target would have multiple benefits for example, improvements to water quality, air quality (Sutton et al., 2014), human health and biodiversity (Houlton et al., 2019).

The SWOT and PESTLE analysis identified influences needed to support a specific and achievable NUE target by detailing opportunities which could assist with the implementation of such a target. Regulatory instruments include BAT/mitigation measures and fertiliser use limits, economic instruments include taxes and subsidies, and communicative instruments include extension services and awareness (Oenema et al., 2011).

Other positive influences include an increase in farm profitability following the implementation of mitigation measures such as precision livestock feeding and matching N supply to demand) which was found as a strength and economic enabler through the analysis. Moreover, through the introduction of a NUE target, there would be an opportunity to involve advisors and consultants which may also lead to the implementation of better advice and practice regarding N use in Scottish agriculture.

Hindering a SMART NUE target

All analysis was based on N targets rather than NUE targets due to the lack of any NUE specific targets in other countries. Therefore, clear evidence on NUE targets is lacking and the analysis of a NUE target for Scotland is based on assumptions through transferring information from N-related targets to NUE.

To achieve any potential NUE targets a range of new techniques, technologies and systems would be required. These are referred to as mitigation measures. There is already a good body of evidence and supporting examples of the implementation of mitigations. These have been identified as a strength and enabler as some examples such as variable rate N application (precision farming) can save farmers money on inputs by only purchasing and applying N as needed. Others, however, require significant capital expenditure with upfront investment of time and money required to implement some of the mitigation measures (for example, low emission slurry application equipment). This has also been identified as a weakness and economic barrier which may be experienced by Scottish farmers. This could directly impact upon the achievability of a NUE target. Similarly, several barriers to uptake of mitigation measures were identified as a threat through the SWOT analysis. Barriers include lack of awareness and knowledge of why and how to improve N use, and farmer’s personal beliefs, both of which may lead to Scottish farm managers finding it difficult to quantify the benefits to their business and understand the relevance of a NUE target. These barriers would generally hinder the achievability of a NUE target.

In trying to make a NUE target relevant in terms of meeting statutory emission reduction targets, there is a risk when reducing N-related emissions, through mitigation measures, that pollution-swapping takes place. An example of this is the decrease in NH3 emissions and an increase in N2O emissions (due to nitrification/denitrification processes) when using slurry injection (a type of low emission slurry application) compared to surface application. Pollution-swapping as an unintended consequence of some mitigation measures was identified as a threat and environmental barrier in introducing a NUE target.

Farmers’ perception of a national NUE target for Scotland may limit target achievability. Scottish farmers may not understand how their practices impact NUE and how introducing on-farm mitigation measures may impact on a general NUE target for Scottish agriculture. For example, questions may arise on how many and at what frequency the relevant mitigation measures need to be introduced by each farmer to achieve this overarching target. To overcome this, some farmers may respond more positively to several more specific targets, for example a reduction of fertiliser input (by a certain amount and by a certain date). Alternatively, ensuring a NUE target is accompanied with very specific and relevant action points on how this NUE target would be achieved so that farmers have a clear understanding on what is expected of them and their farming system to contribute to a national NUE target.

The time taken to create and process the appropriate legislation for a NUE target can be uncertain and longwinded. This process has the potential to directly impact the time-bound element of a SMART NUE target.

In the Netherlands, an ambitious target led to civil unrest where more than 10,000 Dutch farmers have been protesting following government plans to reduce N emissions. Similarly, when targets or limits are seen to be a barrier to economic performance, implementation of new regulation can become challenging, as is seen in the case of revising the approach towards Nutrient Neutrality in England. The use of a SMART target is therefore critical to avoid the implementation of a policy which is neither appropriate nor achievable.

In the main, these examples relate to current exceedances of regulations under the Habitats or Nitrates directives, follow a long period of previous actions and constraints on the farming sector and relate to farming systems which are very different to those present within Scotland. In addition, these regulations are not focused on NUE but rather on the achievement of environmental targets and so do not consider the productive potential of the sector. Notwithstanding these differences, these risks do indicate the importance of well formulated targets, based on sound scientific understanding and with a clear plan for consultation and implementation on their achievement and delivery.

The political and legal barriers identified include the potential for pushback on mitigation measures which are seen to reduce productive output and a concern that Scottish farmers may not comply with regulatory requirements. This could directly impact upon the achievability of a NUE target.

Development of a NUE target for Scotland

Assessment using the Scottish Nitrogen Balance Sheet

The SNBS has been used as a baseline to assess how practices that influence N pools or flows may impact the agricultural NUE value. This dataset contains values for key sectors, pools (stores of N within parts of the N cycle e.g. in manure, in soils or in livestock/crops), and flows of N (movement of N into different pools as the N form changes or is taken up by plant or animals). These flows include inputs to the system (e.g. fertilisers, animal feed), useful outputs (e.g. meat, cereals), and waste (e.g. NO3 leaching, NH3 emissions). Each of these flows have a value in kt N/yr assigned. The NUE is improved by either increasing the output flow values or reducing input and waste flow values. This can be modelled by estimating the impact of a mitigation measure (e.g. improved nutrient planning or reduced protein livestock feed) and applying these values to the relevant N flow in the SNBS (for improved nutrient planning this would be reduced inputs of fertiliser and reduced N emissions to atmosphere). This produces estimates for N flows that can then be summarised in NUE calculations as currently setup in the SNBS, resulting in estimates of improved NUE values (see Appendix E for a detailed methodology and all assumptions).

Mitigation measures

The effect of mitigation measures on Scottish agriculture’s NUE

This section presents and discusses the effects of 18 different mitigation measures on the current NUE of Scottish agriculture.

The table below presents modelled estimates for the NUE of Scottish agriculture, by individual measure and at each future projected target year. The values reflect implementing the relevant measure individually and compared to the current whole-agriculture NUE of 27.2% (i.e. preventing soil compaction may improve total NUE by 0.1% by 2030). The results show the impact for the relevant measure in isolation and do not reflect any combination effects for interactions with other measures. Further detail on the assumptions and methodology can be found in Appendix E. The 2030, 2040 and 2045 scenarios are based on minimal change, continuing recent trends of recent changes in uptake, but including greater increases where there is precedent to, e.g. low emissions spreading techniques all increasing to 95% by 2030 as this will be required under the New General Binding Rules on Silage and Slurry. However, the 2045 Ambitious scenario is based on a transformational change across the sector where there is greater effort to improve NUE to meet a legally binding target. Therefore, the improved NUE in the 2045 and 2045 (Ambitious) scenarios may be viewed as the range where a target may be set, where the lower bound of the range (2045 scenario) is more achievable, while the higher bound (2045 (Ambitious) scenario) would require more effort across stakeholders to be achieved but is a better value.

Table 3 List of mitigation measures and their effect on Scottish agriculture NUE (%) compared to the current whole agriculture NUE of 27.2%. The two 2045 scenarios can be viewed as an ideal range for NUE; where the lower bound (2045 scenario) reflects changes to agriculture planned to come in (current and upcoming legislation, expert judgement on technological developments etc.); while the upper bound (2045 ambitious scenario) reflects the possibility for a greater push from industry and government to improve NUE (financial incentives, increased awareness of N management, etc.).

Measure

2030

2040

2045

2045 (Ambitious)

Avoid excess N

31.23% (-3.02%)

31.90% (-3.48%)

31.90% (-3.48%)

33/41% (-5.59%)

VRNT

27.66% (-0.43%)

27.96% (-0.72%)

28.41% (-1.16%)

30.40% (-3.02%)

Urease Inhibitors

27.57% (-0.35%)

28.08% (-0.86%)

28.35% (-1.12%)

28.70% (-1.47%)

Improving nutrition

27.26% (-0.03%)

27.30% (-0.07%)

28.27% (-1.04%)

28.26% (-1.03%)

Novel crops

27.44% (-0.22%)

27.52% (-0.29%)

27.77% (-0.55%)

27.81% (-0.58%)

Low emission spreading

27.62% (-0.39%)

27.62% (-0.39%)

27.62% (-0.39%)

27.62% (-0.39%)

Rapid incorporation

27.26% (-0.09%)

27.31% (-0.09%)

27.34% (-0.11%)

27.47% (-0.24%)

Low emission housing

27.24% (-0.02%)

27.27% (-0.04%)

27.28% (-0.06%)

27.43% (-0.20%)

Improving livestock health

27.64% (-0.42%)

28.02% (-0.80%)

27.32% (-0.09%)

27.43% (-0.20%)

Slurry cover

27.25% (-0.02%)

27.28% (-0.05%)

27.03% (-0.07%)

27.33% (-0.10%)

Optimal soil pH

27.25% (-0.02%)

27.29% (-0.06%)

27.30% (-0.07%)

27.30% (-0.07%)

Nitrification inhibitor

27.23% (-0.01%)

27.24% (-0.02%)

27.25% (-0.02%)

27.25% (-0.03%)

Improving GI + genomic tools

27.23% (0.00%)

27.23% (-0.01%)

27.23% (-0.01%)

27.25% (-0.03%)

Slurry acidification

27.23% (0.00%)

27.24% (-0.01%)

27.24% (-0.01%)

27.25% (-0.02%)

Preventing soil compaction

27.23% (-0.01%)

27.24% (-0.01%)

27.24% (-0.02%)

27.24% (-0.02%)

Use of catch and cover crops

27.27% (-0.05%)

27.34% (-0.11%)

27.37% (-0.15%)

27.38% (-0.18%)

Legume-grass mixtures

Grain legumes in crop rotations

There are potential interactions/overlaps between several of these measures. Where this occurs, measures cannot be applied on the same unit (area of land/head of livestock) at the same time as they are mutually exclusive. We have avoided double counting these effects by resolving the total maximum applicability across overlapping measures i.e. the combination of measures cannot exceed the total land available to apply the measure to.

The key outcomes are:

  • The measures with the greatest potential improvement on NUE are nitrification inhibitors, improving livestock nutrition, and improving livestock health.
  • Nitrification inhibitors are more effective at improving NUE than urease inhibitors as they can be applied to a greater proportion of fertiliser products used in Scotland (both NO3 and urea-based products, while urease inhibitor can only be applied to urea-based products).
  • Improving livestock nutrition will improve NUE by reducing the overall quantity of N being fed to livestock while maintaining liveweight yield.

Measures that are based on the use of legume crops were not included in the modelling of the new NUE values, as the reduced requirement for inorganic fertiliser input will be offset by increased biological fixation of N from the atmosphere. Both flows are included in the N input values when calculating NUE in the SNBS. Therefore, the total N inputs levels will stay constant, as will the outputs, and so there is no impact on NUE. However, there are benefits of legume crops beyond an improvement to NUE, which should be considered, namely the effects of reduced requirement for inorganic fertiliser inputs (lower GHG emissions), improved soil health and soil function, and reduced costs. This is likely to be economically beneficial to the farmer, as soil health benefits the local ecosystem and improves resilience, reduced fertiliser use avoids emissions from manufacture and transportation of inorganic fertiliser; all of which are benefits from moving to a circular economy.

Potential N savings through implementation

The table below summarises the potential savings of N inputs of mineral fertiliser in both absolute values in kt N yr-1, and relative to the quantity in the current SNBS as a %. The values presented here include fertiliser use savings due to legume-based measures (legume-grass mixtures, and legumes in crop rotations). The effect of these measures is not included in calculations of NUE due to the assumption that the saved fertiliser N application will be replaced by increased N deposition from the atmosphere.

Table 4 Absolute values of N inputs of mineral fertiliser saved in kt N per year and as % of the quantity in the current SNBS when all modelled measures are included. The two 2045 scenarios can be viewed as an ideal range for NUE; where the lower bound (2045 scenario) reflects changes to agriculture planned to come in (current and upcoming legislation, expert judgement on technological developments etc.); while the upper bound (2045 ambitious scenario) reflects the possibility for a greater push from industry and government to improve NUE (financial incentives, increased awareness of N management, etc.).

Year

2021 (kt N yr-1)

Savings (kt N yr-1)

Savings (%)

Savings (kt CO2e yr-1)

2030

143.78

36.36

25.29

160.09

2040

143.78

44.16

32.12

213.41

2045

143.78

53.14

37.96

248.56

2045 (Ambitious)

143.78

78.22

-54.40

361.15

Recommended criteria for target(s) setting for Scotland

When modelling the NUE improvements and the establishment of potential targets, the key criteria for consideration are listed below.

Mitigation measures

The measures/farming practices that have been included for modelling are the result of literature searches and expert judgement. Measures that impact N flows in agricultural systems, and the relevant data, were extracted from literature. These were then reviewed to ensure applicability to Scotland, and any other measures that were identified by experts as being important were also researched.

Current uptake

The current uptake provides a basis from which to estimate what future uptake may be possible and the likely rate of additional implementation. It also supports the calculation of a baseline or counterfactual against which change can be measured. These values come from the same sources which have provided the NUE impact values (see Appendix E for detail on current uptake for each measure).

Applicability

The applicability values refer to the portion of a SNBS N flow that a measure’s impact value can apply to. Expected future uptake

The expected future uptake values are estimates based on expert judgment and consultation within the project team. The values for each measure can be found in Appendix E and are additional to the current uptake levels. These values increase over time to reflect increasing commitment to NUE improvements. The two 2045 scenarios can be viewed as an ideal range for NUE; where the lower bound (2045 scenario) reflects changes to agriculture planned to come in (current and upcoming legislation, expert judgement on technological developments etc.); while the upper bound (2045 ambitious scenario) reflects the possibility for a greater push from industry and government to improve NUE (financial incentives, increased awareness of N management, etc.). The expected future uptake ranges from 1% to 100% depending on the measure and scenario. For example, soil compaction was only expected to increase by 2% even in the 2045 (Ambitious) scenario as it was assumed that where soil compaction is occurring most farmers will already be taking steps to improve it. While low emission spreading techniques increased to 95% by 2030 to reflect the New General Binding Rules on Silage and Slurry. A full example is provided in Appendix G.

Timescales

We modelled potential NUE targets for Scottish agriculture for 2030, 2040, and 2045. These were chosen to align with Scotland’s Climate Change Act 2019 with a target date of 2045 for reaching net zero GHG emissions.

One NUE target for Scottish agriculture or per sector?

Currently, the arable sector is more N efficient than the livestock sector (65% and 10% respectively). This difference is due to inherent qualities of livestock systems with animals unable to process N as protein as efficiently as plants uptake N. The current NUE should, however, be seen as a baseline, and the scale of improvements from this should be the focus rather than an absolute target applicable to all sectors and systems. The majority of measures included in the modelling of NUE improvements target the soil N pools (arable and grass land), therefore separate targets for each sector are advisable.

Analysis of recommendations

The table below presents the estimated NUE values in 2030, 2040, and 2045 based on increased uptake of on-farm measures. As well as an additional value for the year 2045 where increased ambition has been included in the projected uptake values.

Table 5. Potentially achievable NUE estimates in 2030, 2040 and 2054 based on increased uptake of on-farm measures. The two 2045 scenarios can be viewed as an ideal range for NUE; where the lower bound (2045 scenario) reflects changes to agriculture planned to come in (current and upcoming legislation, expert judgement on technological developments etc.); while the upper bound (2045 ambitious scenario) reflects the possibility for a greater push from industry and government to improve NUE (financial incentives, increased awareness of N management, etc.).

 

Potentially achievable NUE estimates (%)

2021 (Current)

2030

2040

2045

2045 (Ambitious)

Whole agriculture

27.2

33.7

35.7

38.2

40.9

The NUE values that are modelled in this study are based on the selected measures, and the achievement of these NUE targets rely on their implementation. Other agricultural practices may impact N flows, as will changes in the size of agricultural sectors.

Similarly, the NUE values that have been calculated are based on the levels of implementation that have been included in the modelling. Achieving these targets in practice will require supporting instruments to encourage the uptake of these measures. As stated in Section 6.2.1, the NUE values in the above table for 2030 and 2040 reflect assumptions on uptake based on minimal change and not a transformational change to the sector (such as the setting of a target). Therefore, these values should not be viewed as potential targets for these years, but as indicators of the feasibility of improvements to NUE in Scottish agriculture.

Sector specific NUE values are not currently feasible due to the calculation set-up in the current SNBS (which flows are considered as inputs/outputs for arable and livestock), and the assumption made in the modelling that production will not increase and only inputs will decrease. This set-up leads to results that make it seem that the arable sector is mining N, which is not the case. Improvements to the set-up of calculations to overcome this barrier are outlined in Section 6.5 below.

Guidance for future implementation

In the current version of the SNBS, the NUE calculations do not align directly with what happens in practice in the different agricultural sectors because there are overlaps and movements of N flows between the different agricultural sectors that are not easily viewed in isolation. For example, in practice, improvements to NUE due to implementation of manure management measures will largely be implemented by the livestock sector. However, given the current set-up of the calculations in the SNBS, N flows related to manure management may not be attributed to the livestock sector NUE values as they will reduce emissions from spreading of organic matter to soils, which would be reported in the arable sector calculation. This would make it more difficult to use the SNBS to set and measure sectoral targets. Therefore, accurately monitoring the changes in NUE and attributing these changes to the correct sector would be important if considering sectoral targets. Accurately representing N flows in the SNBS to the relevant sector may be difficult, due to, for example, data availability, different ways data is collected across mitigation measures and sectors and difficulties in correctly separating overlaps and movements of N flows between the different agricultural sectors, however, could significantly help the feasibility of achieving and monitoring NUE targets.

When reflecting the potential impacts of mitigation measures on the values in the SNBS, certain hurdles resulting from the disaggregation of flows make it more difficult and possibly less accurate. More details of these hurdles, and how they were overcome, can be found in Appendix E, but a key example here is the use of slurry acidification on livestock slurry. In the SNBS there is one flow of N from manure management to atmosphere which includes all manure storage types and all livestock types. However, the implementation potential and mitigation impact potential will vary between storage and livestock types. This required an assumption to be made on the breakdown of this manure management N flow so that the appropriate uptake levels and impact values can be applied to the correct portion of the total N value (in this instance the Scottish Agricultural Census was used). This can be considered a sound approach to reflect the mitigation measures in the current SNBS, however going forward, to improve the ease and accuracy with which targets can be projected and improvements can be measured, a more granular breakdown on the N flows in the agricultural sector in the SNBS are required.

Conclusions

A NUE target for Scotland

The rationale behind setting a NUE target for Scotland is to reduce the impacts of N wastages to the environment to lower GHG emissions and improve water and air quality. NUE values can be used as indicators for N resource use efficiency and as markers for improvement. Scotland is in the unique position to use and regularly update a cross-economy and cross-environment N Balance Sheet (SNBS). The SNBS provides a valuable baseline in the current performance of Scottish agriculture and provides a tool to tackle all forms of N pollution.

However, setting a NUE target is not without challenges and nowhere in the world has yet set a NUE target. NUE values are impacted by various factors (soil type, climate, crop type, livestock type, etc). Whilst research shows that the ideal range for NUE is between 50-90%, it is crucial to understand the different forms of N inputs and outputs and to allocate these correctly to the different farming sectors.

As no other country has yet set a standalone NUE target, we had to solely rely on other N-related targets for our evidence base. Our analysis of the viability of setting a NUE target for Scotland is therefore based on assumptions through transferring information from N-related targets to NUE.

The SWOT and PESTLE analysis carried out in this study highlighted several factors which can influence the success of a SMART NUE target for Scottish agriculture. Importantly, the use of the SNBS would make the target measurable and the fact that many N-related mitigation measures are well understood and already practiced in Scottish agriculture would make the target achievable. However, some mitigation measures require significant capital expenditure, such as slurry management equipment, or increased ongoing investment, such as nitrification inhibitors, or a change in focus, such as better-balanced protein in livestock feed. These changes would need support from the farming sector. Using NVZ regulations as an example, a small study conducted in 2016 (Macgregor and Warren 2016) showed that some farmers regarded the NVZ regulations as “burdensome and costly”. To avoid similar responses to setting NUE targets, farmers would need to be able to quantify the benefits to their business and understand the relevance of a NUE target for climate and the environment. It is therefore important to accompany NUE targets with specific actions points expected by farming businesses. Providing funding to farmers to help implement mitigation measures and share knowledge on the impact to their businesses, the climate, water quality, air quality and biodiversity is likely to aid faster and easier uptake of these measures.

Looking at initiatives worldwide, we know that N use can be targeted in many different forms (fertiliser use, livestock diet, reduction of N waste, reduction of emission of air pollutants, etc.) and alongside the proven mitigation measures discussed above, it is clear that improvements to NUE are achievable.

Modelling NUE improvements using the SNBS

In this study, the SNBS has been used to model NUE improvements by estimating the impact of a mitigation measure and applying these values to the relevant N flow in the SNBS. It is important to note that these results show the impact for the relevant measure in isolation so do not reflect any combination effects for interactions with other measures. In the arable sector, the mitigation measures with the greatest potential to improve NUE are the use of variable rate N application (precision farming) and the use of nitrification inhibitors potentially increasing NUE to 28.8% and 29.7%, respectively, by 2045. In the livestock sector, improving nutrition and improving livestock health (NUE of 31.7% and 29.4% respectively by 2045) have the greatest potential. Overall, the modelling suggests that total NUE of Scottish agriculture could be increased to 38.2-40.9% by 2045, depending on the level of implementation of mitigation measures.

Sector specific NUE values are not presently feasible due to the calculation set-up in the SNBS and the assumptions that production will remain stable, with only inputs decreasing. In the current version of the SNBS, the NUE calculations do not align directly with what happens in practice in the different agricultural sectors because there are overlaps and movements of N flows between the different agricultural sectors that are not easily viewed in isolation and not necessarily attributed to the correct sector. For example, mitigation measures around manure management will, in practice, be mainly implemented by the livestock sector but will, in the current calculations, be attributed to the arable sector because they are linked to reduced emissions from spreading of organic matter to soils.

The feasibility of a NUE target for Scotland

This research indicates that a NUE target for Scotland is not currently feasible. We see potential for such a target in the future but recommend to first consider several points for improvement.

  • The SNBS. Improvements to the calculations and attributions of flows of N to the different measures and sectors are required. The modelling for this report depends on assumptions and figures from another CXC report (Eory, et al., 2023). We recommend updating this data with real on farm data to better inform assumptions that follow from it.
  • The sectors. Currently, the arable sector is more N efficient than the livestock sector (65% and 10% respectively). Sector specific targets would be helpful due to differences in current NUE, N inputs and N wastages but this is presently not possible due to the current limitations in the SNBS.
  • The mitigation measures. More data on the impacts of mitigation measures under Scottish conditions would increase the accuracy of modelling achievable aims. Since NUE values are both indicators of resource efficiency and markers for improvement, it is possible to focus on mitigation measures with the most potential to improve NUE values.
  • Farmers. It is highly important to ensure that targets and measures are clearly understandable and achievable for farmers to create support from the farming sector.

A potential target figure?

If a NUE target was set, this could be in line with the modelled potential NUE estimates of 38.2-40.9% by 2045, depending on mitigation measure implementation. To achieve greater improvement, a combined push from industry and government (financial incentives, increased awareness of N management, etc.) is required. This additional push is reflected in our ‘Ambitious scenario’.

However, based on our research findings, the barriers identified to implementing an achievable and successful NUE target and the need for farmer and industry support to achieve changes in practices and expectations, we conclude that focusing on reducing N waste is likely to have more success than NUE targets as a policy option. Experience from the United Nations Environment Assembly’s discussions on N and the Green Deal’s Farm to Fork targets, has shown more success in including the reduction of N pollution in policy when focusing on N waste over NUE targets. NUE can instead be used as a technical tool to mark improvements, with the SNBS key to setting a baseline and providing a visualisation of the combined impacts of implemented mitigations measures over time. We therefore recommend setting a target for N waste.

An alternative – a N waste target?

Opportunities for setting a N waste reduction target include:

  • It is an easier concept to communicate to the farming community and other N producing sectors.
  • It gives the opportunity to value any N as a resource until it is lost as waste, creating options for greater collaboration between the arable, horticulture and livestock sectors. Any potential bias towards a sector will be avoided.
  • Each individual farmer and land manager would be encouraged to reduce N waste for the economic and environmentally beneficial outcomes. The positive messages around a N waste target would be likely to create support from the farming sector.
  • Achievements towards an N waste target would achieve reductions in national NUE thereby achieving the same objectives without the current issues around NUE targets.

Following the Colombo Declaration of 50% reduction of N waste and the Green Deal target of reducing nutrient waste by 2030, a reduction of 50% of N waste in Scottish agriculture would align with other examples. However, we recommend further research to determine a realistic N waste target for Scotland.

Research gaps for setting a N waste target

In the SNBS, N flows would need to be properly assigned to N waste and N re-use. Legumes would need to be included in the SNBS because N waste is likely to be lower than N input. A SMART target analysis for N waste would be beneficial to set a challenging and realistic target. It would be helpful to closer investigate the relationship between N waste and NUE targets if a NUE target is the long-term aim.

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Appendix / Appendices

Appendix A: Nitrogen and its relevance to agriculture

Leaching and the effects on eutrophication

Leaching is the loss of N (as nitrate) as water drains through the soil moving nitrate away from the root zone. Both organic forms of N (such as slurry and manures) and inorganic fertilisers are liable to leaching. When nitrate is leached from soils, it can enter watercourses contributing to environmental problems such as eutrophication. Eutrophication is an accumulation of nutrients in watercourses causing excessive plant and algal growth resulting in reduced water quality and impacts upon fish, invertebrates and plant diversity. The extent of leaching is determined by factors such as soil type, crop cover, land management methods, geological characteristics and meteorological conditions prior to, during and following the application of the nutrients.

How NH3 is emitted from agricultural sources

Loss of ammonia which is a significant air pollutant impacting upon both human health and biodiversity (respiratory harms and nutrient enrichment of sensitive habitats) is common from agricultural systems. Ammonia is lost through volatilisation of ammonium (NH4+).

How N2O is emitted from agricultural sources

Nitrous oxide is emitted in the process of denitrification, a bacterial process in waterlogged soils that converts nitrate to nitrous oxide and N2 (for more explanation regarding the chemical processes involved please see Annex F). N2O is a potent greenhouse gas and forms a significant contribution to agriculture’s impact on climate warming.

Appendix B: Chemical processes of Nitrogen

Appendix C: Rapid evidence assessment methodology

The Rapid Evidence Assessment (REA) methodology used for this project aligns with NERC methodology and comprised of the following steps.

  • Define the search strategy protocol, identify key search words or terms, define inclusion/exclusion criteria. A list of key words, terms and search strings were created and reviewed by the project steering group to direct the REA review to the most relevant sources.
  • Searching for evidence and recording findings. Literature was searched using Google Scholar, utilising our accounts with Science Direct and Research Gate to access restricted PDF’s where required. When searching through Government websites (to find policy initiatives and associated targets), the search engine Google was used. Searches were divided into academic literature and government websites (including farming press and industry). A unique search reference was assigned for each individual search, and the date, search string used, total number of results found, and the total number of relevant papers found were recorded. Examples of search strings include:
  • “Nitrogen” “target” “Europe”
  • NH3 target agriculture
  • Nitrate leaching target
  • Emission reduction target Denmark

All results were recorded in an excel spreadsheet with information extracted on the following:

  • Country
  • Target
  • Target timeframe
  • Benefits and risks/challenges of proposed target
  • Mitigation measures (introduced, planned and proposed/suggested)

A RAG (red, amber, green) rating was also assigned for each source, based on the following criteria:

Description

Rating

Quality

Peer reviewed journal, sound data sources and methodology

Green

Government funded research reports, sound data sources and methodology

Green

International Nitrogen Management System (INMS)

Green

Research funded by NGOs (e.g. AHDB), sound data sources and methodology

Amber

Work is unreliable because of unreliable data sources, or limited sources, or because the method is not robust

Red

Information from websites, blogs etc., of unknown quality

Red

Relevance

Timeframe: within last 10 years

Green

Timeframe: within last 20 years

Amber

Timeframe: older than 20 years

Red

  • Screening. Sources of evidence were then screened initially by title and then accepted papers were screened again using the summary or abstract. Literature was screened for information on the following inclusion criteria:
  • Nitrogen target (including but not limited to target for NUE or nitrogen emissions, or nitrogen fertiliser use, or nitrogen deposition)
  • Benefits and risks of introducing a target
  • Mitigation methods that improve NUE, or decrease nitrogen inputs
  • Extract and appraise the evidence. The screening provided an organised list of papers which enabled evidence to be extracted directly from the literature into the report. Literature extracted also guided the internal workshop and supported information included in the SWOT and PESTLE tables.

How was the evidence found used. Evidence gathered from the REA was used to identify the different types of N targets used in other countries and provided a discussion following examples of the relevance of these targets to Scottish agriculture (section 4). The evidence was also used to identify the benefits and risks of setting a NUE target for Scotland and assisted the SWOT and PESTLE analysis (section 5) and to inform criteria and underpin recommendations for setting an appropriate target/s for Scotland.

Appendix D: Country-specific changes (%) in NUE values from 1961 to 2014

Table 6: Country-specific changes (%) in NUE values from 1961 to 2014 (Our World in Data)

Country or region

Year

Relative change (%)

1961 (%)

2014 (%)

Denmark

39.68

74.29

87

Finland

34.51

57.08

65

France

37.89

73.87

95

Germany

37.71

62.62

97

Greece

65.22

50.25

11

Hungary

45.26

92.95

105

Iceland

0.38

0.21

43

India

43.73

34.34

21

Indonesia

48.2

80.38

67

Ireland

77.02

86.9

13

Italy

47.85

52.64

10

Japan

37.36

27.87

25

Latvia

58.75

61.41

5

Luxembourg

49.71

18.29

63

Malaysia

42.81

262.09

512

Mexico

75.78

45.74

40

Netherlands

18.15

37.1

104

New Zealand

10.26

5.23

49

North Korea

49.68

41.85

16

Norway

20.08

20.35

1

Poland

48.16

45.27

6

Portugal

33.39

19.2

42

Romania

40.8

107.17

163

Russia

64.37

125.2

95

Sweden

43.15

53.01

23

Switzerland

50.53

36.66

27

UK

28.36

66.69

135

USA

71.9

71.61

0

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Appendix E: Analysis & recommendation development Methodology

  • Data collection

Relevant measures were collated from results of the REA. The impact factors for these measures on N flows was extracted into an excel file.

  • Data extraction

All relevant data points were extracted from the papers into an Excel spreadsheet manually.

  • Data appraisal

A RAG rating was applied to all data sources based on the quality of the data (including publishing date, assumptions made, applicability etc.). Where data was considered to be very poor quality, alternative sources to fill or improve this data point were sourced.

  • Mapping

Relevant mitigation measures were mapped on to the SNBS according to what nitrogen flows they impacted. This allowed for accurate modelling of the change in nitrogen flow, and subsequently nitrogen use efficiency, if the measures are implemented at the estimated uptake rates in the given years.

  • Calculations

Once the impact values had been mapped on to relevant N flows, they were evaluated to ensure that the theory behind these values relate and can therefore be applied to the values in the SNBS. This involved ensuring that each measure had a relative impact value as percentage, and that the baseline is applicable to that in the SNBS.

Applicability: the portion of the relevant flow in the SNBS that the measure/impact value applies to e.g. emissions from livestock are grouped in one flow in the SNBS, and so a measure/impact value relevant to only dairy animals can only be applied to a portion of the N flow value. There were several sources used to determine this granularity of application. For livestock sectors the Scottish agricultural census data was used. The total livestock number in heads was divided by the total number of livestock from all sectors and reported as a percentage. Fertiliser use was determined from data within the Agricultural SMT produced by ADAS.

Some measures that include N fixation may not improve NUE but will reduce mineral N inputs.

Current uptake: An estimation of the portion of the relevant N flow that is subject to the impact of the measures. This is subtracted from the overall applicability as the impact is already considered in the current NUE values. In this way double counting of impacts is avoided.

Maximum future impact: Calculated as applicability minus current uptake, multiplied by the impact value. This calculates the impact the measure may have if implemented on all remaining applicable units. The value is then multiplied by the projected future uptake value in each of the time points to produce an estimate for the impact that could be expected.

  • Quality Assessment

All data inputs, calculations, and outputs of this task were reviewed internally by the sector experts to ensure robustness and validity. Where possible the results were also compared to peer reviewed literature to ensure that they were consistent with the current scientific understanding.

  • Assumptions around SNBS

There is no flow that relates to N from soil into grass, so impacts on this could not be quantified in the SNBS.

Crop residue N is recycled within the system. Therefore, this flow is not considered in the NUE calculations in the SNBS, and so any impacts to crop residue N due to implementation of measures will not be reflected in an improvement to NUE. To compensate for this, improvements to crop residue N was modelled as a reduction in N inputs from fertilisers.

There is around 30kt N unaccounted for through livestock flows. This is perhaps accounted for in what is considered in the report as ‘stocks’ – i.e. an amount of N in living livestock at any one time.

Appendix F: Description of measures and assumptions

In the following tables, where the source is given as “other CXC paper” this is referring to the paper Eory, V., et al. (2023) and “MACC Update” refers to the paper Eory V., et al. (2015).

  • Preventing soil compaction

Approximately 20% of arable land in Scotland is susceptible to soil compaction and is therefore eligible to have compaction prevention applied. This measure is expected to increase yields and crop residue N, and so is assumed to reduce mineral N requirements.

Paper

CXC

CXC

CXC

CXC

CXC

CXC

Sector

Arable

Grassland

Arable

Grassland

Arable

Grassland

N Effect

Crop Residue N

Crop Residue N

Yield

Yield

N2O Emission Factor

N2O Emission Factor

Value

2%

1%

2%

1%

-6%

-6%

Applicability

20.00%

20.00%

20.00%

20.00%

20.00%

20.00%

Current Uptake

0%

0%

0%

0%

0%

0%

Maximum Future Impact

2.00%

1.00%

2.00%

1.00%

-6.00%

-6.00%

Uptake 2030

1%

1%

1%

1%

1%

1%

Uptake 2040

2%

2%

2%

2%

2%

2%

uptake 2045

2%

2%

2%

2%

2%

2%

2030

-0.01%

-0.01%

-0.01%

-0.01%

-0.04%

-0.04%

2040

-0.03%

-0.02%

-0.03%

-0.02%

-0.10%

-0.10%

2045

-0.04%

-0.02%

-0.04%

-0.02%

-0.13%

-0.13%

  • Optimal soil pH

This measure involves applying lime to soils to ensure that soil pH is in the optimal range for N availability. This means that when applying N fertilisers there will be less excess N as it will be more bioavailable and taken up by crops. This has been found to increase crop residue N and yield, both by 6%, while reducing the emission of N2O by 3%, in arable and grassland. It has previously been assumed that approximately 9% of arable land and 22% grassland are applicable to have pH optimised.

Paper

CXC

CXC

CXC

CXC

CXC

CXC

Sector

Arable

Grassland

Arable

Grassland

Arable

Grassland

Nitrogen Effect

Crop Residue N

Crop Residue N

Yield

Yield

N2O Emission Factor

N2O Emission Factor

Value

6%

6%

6%

6%

-3%

-3%

Applicability

9.00%

22.00%

9.00%

22.00%

9.00%

22.00%

Current Uptake

0%

0%

0%

0%

0%

0%

Maximum Impact in Future

-0.56%

-1.37%

0.56%

1.37%

-0.27%

-0.66%

2030

-0.17%

-0.41%

0.17%

0.41%

-0.08%

-0.20%

2040

-0.22%

-0.55%

0.22%

0.55%

-0.11%

-0.26%

2045

-0.42%

-1.03%

0.42%

1.03%

-0.20%

-0.50%

Uptake 2030

30%

30%

30%

30%

30%

30%

Uptake 2040

40%

40%

40%

40%

40%

40%

uptake 2045

75%

75%

75%

75%

75%

75%

  • Use of catch/cover crops

Catch/cover crops are non-productive plants cultivated between catch crops with the effect of taking up excess N that was left in soil, having not been taken up by the preceding cash crop. This reduces the amount of N (in the form of NO3 ) that is lost in leaching by 45%. The applicability of this measure to crops has previously been set to 34%.

Paper

MACC Update

Sector

 

Nitrogen Effect

Frac_Leach

Value

-45%

Applicability

34.00%

Current Uptake

30.00%

Maximum Future Impact

-10.71%

2030

-0.75%

2040

-1.82%

2045

-2.36%

Uptake 2030

7%

Uptake 2040

17%

uptake 2045

22%

  • Variable rate nitrogen application

Variable rate nitrogen application (VRNT) is where a digital map or real-time sensors supports a decision tool that calculates the N needs of the plants, transfers the information to a controller, which adjusts the spreading rate (Barnes et al. 2017). This measure is applicable to all land that receives fertiliser. 2-22% of farms use precision farming technologies and 16% used variable rate application, though only 11% use yield mapping (25% cereal farms, 18% other crop farms, 5% pig/poultry and dairy farms, 2% grazing livestock farms, 11% mixed farms). This measure can increase yield, reduce fertiliser use rates, and increase crop residue N. As with all measures yield is kept constant with current levels, and crop residue N is considered through a decrease in N fertilisation. Therefore, this measure is modelled as a decrease to N inputs through three mechanisms.

Paper

CXC

CXC

CXC

CXC

CXC

CXC

Sector

Crop

Grassland

Crop

Grassland

Crop

Grassland

Nitrogen Effect

N fertilisation rate

N fertilisation rate

Crop yield

Crop yield

Crop residue N

Crop residue N

Value

-5%

-5%

-3%

-3%

-3%

-3%

Applicability

100.00%

100.00%

100.00%

100.00%

100.00%

100.00%

Current Uptake

21.50%

2.00%

21.50%

2.00%

21.50%

2.00%

Maximum Impact in Future

-3.93%

-4.90%

-2.36%

-2.94%

-2.36%

-2.94%

2030

-0.27%

-0.34%

-0.16%

-0.21%

-0.16%

-0.21%

2040

-0.67%

-0.83%

-0.40%

-0.50%

-0.40%

-0.50%

2045

-0.86%

-1.08%

-0.52%

-0.65%

-0.52%

-0.65%

Uptake 2030

7%

7%

7%

7%

7%

7%

Uptake 2040

17%

17%

17%

17%

17%

17%

uptake 2045

22%

22%

22%

22%

22%

22%

  • Urease Inhibitors

Urease inhibitors slow down the hydrolysis of urea to ammonia when urea-based fertilisers are applied to soils, reducing ammonia emissions and increasing the N available to plants.

Paper

CXC

CXC

CXC

Sector

Crop

Crop

Crop

Nitrogen Effect

N2O Emission Factor

N leaching

N fertilisation rate

Value

-27%

-13%

-17%

Applicability

8.40%

8.40%

8.40%

Current Uptake

0.00%

0.00%

0.00%

Maximum Impact in Future

-2.27%

-1.10%

-1.41%

2030

-0.56%

-0.27%

-0.35%

2040

-1.35%

-0.65%

-0.84%

2045

-1.75%

-0.85%

-1.09%

Uptake 2030

25%

25%

25%

Uptake 2040

60%

60%

60%

uptake 2045

77%

77%

77%

  • Nitrification Inhibitor

Paper

CXC

CXC

Sector

Crop

Crop

Nitrogen Effect

N2O Emission Factor

N2O Emission Factor

Value

-60%

-30%

Applicability

7.50%

36.50%

Current Uptake

0.00%

0.00%

Maximum Impact in Future

-4.50%

-10.95%

2030

-0.53%

-1.28%

2040

-1.27%

-3.10%

2045

-1.65%

-4.02%

Uptake 2030

12%

12%

Uptake 2040

28%

28%

uptake 2045

37%

37%

  • Improved Nutrition

Improving the nutrition of livestock can involve matching N in feed to the needs of the animal, improving the availability of N in the feed to animal, improving the digestibility of the feed so that more N is utilised by the animal and converted to liveweight. This can reduce N inputs and/or reduce N losses while keeping useful N outputs constant, and so increases NUE. From previous modelling of this measure in Scotland it was found that the N content of feed could be reduced by 2% in beef, poultry, and dairy, while excreted N could be reduced by 5% in pigs and 2% in sheep. The applicability of this measure for each livestock type is based on the proportion of total livestock units of each livestock type based off the Scottish Agricultural Census. The current uptake is based off data from previous reports modelling this measure in Scotland.

Paper

CXC

MACC (2020)

MACC (2020)

MACC (2020)

CXC

Sector

Beef

Pigs

Poultry

Dairy

Sheep

Nitrogen Effect

Feed

N Excreted

Feed

Feed

N excreted

Value

2%

5%

2%

2%

-2%

Applicability

42.46%

11.50%

10.35%

10.84%

23.03%

Current Uptake

20.00%

80.00%

80.00%

80.00%

20.00%

Maximum Impact in Future

0.68%

0.12%

0.04%

0.04%

-0.37%

2030

0.08%

0.01%

0.00%

0.01%

-0.04%

2040

0.19%

0.03%

0.01%

0.01%

-0.10%

2045

0.25%

0.04%

0.02%

0.02%

-0.14%

Uptake 2030

12%

12%

12%

12%

12%

Uptake 2040

28%

28%

28%

28%

28%

uptake 2045

37%

37%

37%

37%

37%

  • Improved health

This measure includes eliminating issues including worms, liver fluke, and lameness, increasing the productivity/efficiency of the animals. While in theory 100% of the herd could have improved health (the stance taken in CXC A scenario), an 80% applicability value was chosen, following the assumption in CXC marginal abatement. This will produce a slightly more conservative estimate of the impact on NUE, to allow for not all diseases/health issues that contribute to lower productivity being treatable/eradicated, and a portion of the herd that may already be achieving higher health. Previous studies focusing on improving livestock health to mitigate nutrient loss, greenhouse gas loss etc. focused on the mechanism of increased productivity. Therefore, as we are keeping yields constant in this model the increased productivity is factored in as a reduction in feed inputs. 

Paper

CXC

CXC

CXC

Sector

Dairy

Beef

Sheep

Nitrogen Effect

Milk Yield

Liveweight

Liveweight

Value

6%

6%

10%

Applicability

41.63%

24.05%

8.21%

Current Uptake

0.00%

0.00%

0.00%

Maximum Future Impact

2.66%

1.53%

0.86%

2030

0.80%

0.46%

0.26%

2040

1.50%

0.87%

0.49%

2045

1.95%

1.13%

0.63%

Uptake 2030

30%

30%

30%

Uptake 2040

57%

57%

57%

uptake 2045

73%

73%

73%

  • Livestock Genetics

Livestock genetics techniques can be used with various goals including increasing productivity, climate resilience, or reducing emissions. For improving NUE of livestock systems the key goal is increasing efficiency i.e. increasing the utilisation of N and yield of livestock products, compared to the feed N intake levels. The uptake of using better genetic material is only around 20-25% in the dairy herd, and still lower in the beef herd (Defra 2018). The outcomes of this measure will depend on the breeding tools used and the breeding goal chosen. Three more specific measures have been gathered from the literature, and their potential impact on NUE has been modelled. These are:

  • Increased uptake of the current approach in the dairy herd,
  • Using the current breeding goals but enhancing the selection process by using genomic tools, in dairy and beef,
  • New breeding goals to include lower GHG emissions, using genomic tools.

In 2018 usage of improved genetic material was reported as 20-25% in the dairy herd, and less in the beef herd. However, several previous projects modelling similar measures set the current uptake at 0% of both dairy and beef herds.

Paper

CXC

CXC

CXC

Sector

Dairy

Dairy

Beef

Nitrogen Effect

Milk yield

Milk protein

Liveweight

Value

1%

1%

0%

Applicability

10.84%

10.84%

42.46%

Current Uptake

60.00%

60.00%

25.00%

Maximum Future Impact

0.04%

0.04%

0.08%

Uptake 2030

15%

15%

5%

Uptake 2040

25%

25%

10%

uptake 2045

35%

35%

20%

2030

0.00%

0.00%

0.00%

2040

0.00%

0.00%

0.00%

2045

-0.01%

-0.01%

-0.03%

  • Slurry acidification

Livestock excreta is susceptible to N volatilization, leading to losses to the atmosphere using storage, and leaching during spreading. Acidification of slurry can immobilize the N and reduce these losses. The impact of acidification is largely measured and reported in reductions to emissions, however, as the emissions values are not considered in the NUE calculations this has to be transformed to an impact on inputs. Higher N in slurry will increase yields/maintain yields with lower inputs. Therefore, in this model we include the impact of slurry acidification as a reduced input of N to land receiving fertiliser.

Paper

CXC

CXC

CXC

MACC Update

MACC Update

MACC Update

Sector

Dairy

Beef

Pigs

Dairy

Beef

Pigs

Nitrogen Effect

NH3 Volatilisation

NH3 Volatilisation

NH3 Volatilisation

N2O Emission

N2O Emission

N2O Emission

Value

-75%

-75%

-75%

-23%

-23%

-23%

Applicability

2.28%

0.85%

2.19%

2.28%

0.85%

2.19%

Current Uptake

0.00%

0.00%

0.00%

   

Maximum Future Impact

-1.71%

-0.64%

-1.64%

-0.52%

-0.20%

-0.50%

Uptake 2030

7%

7%

7%

7%

7%

7%

Uptake 2040

17%

17%

17%

17%

17%

17%

uptake 2045

22%

22%

22%

22%

22%

22%

2030

-0.12%

-0.04%

-0.11%

-0.04%

-0.01%

-0.04%

2040

-0.29%

-0.11%

-0.28%

-0.09%

-0.03%

-0.09%

2045

-0.38%

-0.14%

-0.36%

-0.12%

-0.04%

-0.11%

  • Slurry store cover

Based on an impermeable slurry cover. Impact and uptake values taken from previous CXC paper. The flow in the SNBS does not distinguish between NH3 emissions from housing and spreading and N2O emissions from animal husbandry in general. The portion of each of these gaseous emissions was then extrapolated from the SMT. An impermeable cover is applicable to 100% of slurry tanks and lagoons as there is no available uptake data.

Paper

CXC

CXC

CXC

CXC

CXC

CXC

Sector

Dairy

Dairy

Beef

Beef

Pigs

Pigs

Nitrogen Effect

NH3 Volatilisation

N2O Emission

NH3 Volatilisation

N2O Emission

NH3 Volatilisation

N2O Emission

Value

-80%

-100%

-80%

-100%

-80%

-100%

Applicability

6.25%

2.71%

0.85%

0.85%

4.26%

4.26%

Current Uptake

0.00%

0.00%

0.00%

0.00%

24.00%

24.00%

Maximum Future Impact

-5.00%

-2.71%

-0.68%

-0.85%

-2.59%

-3.23%

Uptake 2030

18%

18%

18%

18%

18%

18%

Uptake 2040

43%

43%

43%

43%

43%

43%

uptake 2045

55%

55%

55%

55%

55%

55%

2030

-0.88%

-0.47%

-0.12%

-0.15%

-0.45%

-0.57%

2040

-2.13%

-1.15%

-0.29%

-0.36%

-1.10%

-1.37%

2045

-2.75%

-1.49%

-0.37%

-0.47%

-1.42%

-1.78%

 

  • Low Emission Housing

Acid air scrubbers can remove nitrogen from air, reducing NH3 emissions, which can then be applied to soils as N fertiliser, and essentially recovering more N in useful outputs by reducing waste N in emissions. Approximately 90% of recovered N can be reinput into the soil. The removal efficiency depends on the specific machinery used and approximately 90% can be expected for acid air scrubbers.

Paper

Comparing environmental impact of air scrubbers for ammonia abatement at pig houses: A life cycle assessment (sciencedirectassets.com)

Comparing environmental impact of air scrubbers for ammonia abatement at pig houses: A life cycle assessment (sciencedirectassets.com)

Sector

Pigs

Poultry

Nitrogen Effect

Recovering emissions

Recovering emissions

Value

-81%

-81%

Applicability

12%

10%

Current Uptake

  

Maximum Impact in Future

-9.32%

-8.38%

Uptake 2030

7%

7%

Uptake 2040

17%

17%

uptake 2045

22%

22%

2030

-0.65%

-0.59%

2040

-1.58%

-1.42%

2045

-2.05%

-1.84%

  • Novel Crops

Novel crops (crops with improved NUE) is designed to reflect the impact of growing new cultivars of crops that can maintain (or improve yields) with a lower requirement for N inputs as fertiliser. Previous

Paper

MACC Update

Sector

Arable

Nitrogen Effect

N fertilisation rate

Value

-9%

Applicability

70.00%

Current Uptake

0.00%

Maximum Impact in Future

-6.30%

2030

-13.23%

2040

-2.52%

2045

-4.73%

Uptake 2030

30%

Uptake 2040

40%

uptake 2045

75%

  • Rapid Incorporation

Paper

SMT

Sector

 

Nitrogen Effect

NH3 Volatilisation

Value

-41%

Applicability

100%

Current Uptake

26%

Maximum Impact in Future

-30.34%

Uptake 2030

12%

Uptake 2040

28%

uptake 2045

37%

2030

-9.10%

2040

-8.60%

2045

-11.12%

  • General Assumptions:
  • Take the total inputs and subtract the total loss to atmosphere as NH3 and loss to run off and leaching
  • Maybe assume that N2 and NOx stay constant, NH3 and N2O, estimate the losses and subtract from inputs
  • Ignore crop residue N, check how this impacts flow
  • Increased N fixation will lead to reduced mineral fertiliser inputs, balance out
  • Reduced losses (N2O, NH3, leaching) will reduce inputs in equal amounts (may need to apply a percentage to this, as farmers may only reduce inputs by 80%, may have to look into the literature)
  • Maintain yield (useful outputs), and so any change to output will be modelled as a change to inputs. This is based on the principle that there will be economic drivers at play that will mean on a Scotland wide scale production levels will be maintained, and so if there is a yield increase/decrease on one farm this will be balanced out by the converse on a different farm. Any yield increase/decrease will be felt as the converse in inputs – feed, fertiliser etc. will be reduced in line with the estimated increase of milk, liveweight, crop, etc.
  • All legume measures will not impact NUE as any saving in N fertilisation will be balanced by increased biological fixation.
  • Assumed that legumes are included once in every five years. Therefore, a fertiliser saving is felt in two of every five years and so impacts 40% of the mineral fertiliser input to crops flow (one year (20%) will be saved from the legume cycle, and one year (20%) from the subsequent crop year due to residual soil N).
  • Within the SNBS, nitrogen flows to or from livestock pools were given as a single value for all livestock, rather than by type. However, the measures relating to livestock were species-specific (e.g. slurry acidification in dairy slurry and pig slurry). To compensate for this the number of heads of each livestock type (from the Scottish agricultural census) was converted to livestock units, and then the proportion of total livestock amount of each type was calculated and applied to the relevant measures.
  • A single flow value is provided in the SNBS for all mineral fertiliser to crops and all mineral fertilisers to grass, however several of the measures only impact a certain type of fertiliser or may have a different impact depending on the type of fertiliser.

Appendix G: SWOT and PESTLE Analysis

The risks and benefits to Scotland from determining a NUE target were determined through giving consideration to numerous avenues of information and data. Evidence gathered following the completion of Task 1 (evidence review) focusing upon risks and benefits of setting NUE targets in other countries were collated and analysed. This was followed by an internal workshop, led by key experts within the agricultural field, to determine the applicability of the information to Scotland, during which time additional risks and benefits were identified. Following the internal Workshop, a more detailed study of the aspirations and trends in agricultural practices set by the Scottish Government was undertaken. The SWOT (strengths, weaknesses, opportunities, threats) and PESTLE (political, economic, sociological, technological, legal and environmental) tables were populated to better understand the complexities of the information gathered by Ricardo, with the analysis tools providing a summary of the risks and benefits of setting a NUE target in Scotland and demonstrating how a range of influences can support or hinder the achievement of a NUE target. The points presented in both the SWOT and PESTLE analysis have varying degrees of severity therefore a judgment on overall supporting and hindering influences cannot be made on the number of points alone.

SWOT

Strengths, weaknesses, opportunities, and threats (SWOT) of setting N-related targets were analysed based on the information gathered on N targets in other countries. We also included analysis of GHG and climate related targets where relevant to increase the body of information. This information was then used to assess applicability of setting a NUE target for Scottish agriculture with the limitation that the analysis was based on N, GHG and climate related rather than NUE specific targets. The SWOT analysis shows a range of influences which can support or hinder the achievement of a NUE target.

 

Strengths of a NUE target

Weaknesses of a NUE target

Internal

  • Raises awareness of the contribution of N use to GHG emissions
  • Mid-point assessments allow long-term benefits of N deposition reduction to be communicated on political timescales
  • Regulation has a strong impact on land-management decisions
  • Targets are meaningful reference values which convey a desired outcome
  • Various treaties and regulations have put limits or targets on N use; information is available in terms of reducing N pollution (e.g., NVZ)
  • Technologies and measures that can support the success of a NUE target already exist and continue to be developed
  • Data on attainable NUE exists in literature
  • Supports fertiliser efficiency, reducing imported input demand
  • Many mitigation measures are relatively low cost and accessible
  • NUE can be estimated at different spatial and temporal scales
  • Improvements in NUE are achievable
  • A voluntary approach may attract more farmer involvement
  • Can support a NUE indicator for the food system including food waste, transport, exports etc , supporting wider national policies
  • Support farm profitability by reducing spend on inputs
  • Work is ongoing to increase the data availability for GHG mitigation potential, and the economic costs and benefits of mitigation measures
  • Some government funding is needed, for example, to help cover large upfront investments for some measures e.g. low emission spreading machinery
  • Enforcing measures requires political will that may be in tension with the current rhetoric around food security.
  • Some mitigation measures may need to be repeated or changed frequently which requires monitoring (e.g. nitrification inhibitors need to be used annually)
  • There is no single universally applicable path for increasing NUE which can reduce action due to confusion on what to do
  • To set a target, accurate current uptake levels for relevant measures need to be known (high current uptakes limit the potential for further improvements to NUE), which is not currently the case. Some measures may already be in widespread use, which limits the potential for additional reductions.
  • A target with a voluntary approach may limit success and require ‘buy-in’ from farmers
  • Biogeochemical hysteresis effects are not yet well understood quantitatively (Being able to quantify the indirect effects of introducing new mitigation measures (e.g., change of N management) on the wider ecosystem (e.g., N cycle) are not well understood).
  • Predicting future uptake levels for mitigation measures is difficult
  • Improving NUE reduces emissions of N, but does not eliminate them, so there is target limitation
  • Some measures that are good for N use (e.g., legume crops) may not be reflected in the SNBS
  • A clear, nationwide strategy to support farmers in implementing measures on a broad scale to improve NUE on farm is currently lacking
 

O Opportunities presented by having a NUE target

Threats presented by having a NUE target

External

  • The SNBS will allow annual monitoring
  • To date, progress has been small in reducing nutrient pollution and N emissions from agricultural sources, improvements in NUE offer opportunities to significantly reduce N emissions without significantly disproportionate costs to the agricultural sector
  • Drive better practices on farm
  • Binding targets can deliver high reductions in N losses and encourage farmers beyond mitigation and into prevention
  • Supports effective and efficient policy
  • Proposing multiple mitigation measures suited to different farming types can increase uptake
  • Learn from other policy initiatives e.g. The Colombo Declaration
  • Further promote the development of technologies and measures that support better N use
  • Farm support programs for purchase/modernisation of agricultural equipment
  • Farmers can use N modelling tools to assess the effectiveness of different mitigation measures
  • Build upon the sector’s work to increase adoption of region and farm-specific measures
  • Training can be far-reaching and can be combined with incentives and verification at all stages
  • Private markets could pay farmers to adopt practices that produce ecosystem services
  • Knock on benefits of better NUE include
  • Reduction of other pollutants e.g., GHGs, NH3
  • Improvement of water quality
  • Improvements to air quality
  • Improvements to human health
  • Biodiversity benefits
  • Saves farmers’ money
  • Binding N targets have led to civil unrest in other countries so potentially, government enforcement of a target (i.e. introducing a tax) may cause civil unrest
  • A voluntary approach with further reductions in limits may result in less buy-in from farmers
  • ‘Overly’ ambitious targets may drive farmers out of business with community implications
  • Unintended consequences e.g., pollution swapping
  • Even if measures are as successful as anticipated and are fully adopted, the cumulative reduction may be less than the estimated potential
  • Setting an unambitious/low target could be seen as a “parody which pushes responsibility onto other sectors”
  • ‘Quick-win’ results may hinder future development
  • Implementation of mitigation measures may need monitoring and enforcement
  • Biogeochemical hysteresis effects
  • Mitigation measures may interfere with other regulations e.g., land-use regulation
  • Challenging to change animal production technology, change agrotechnics and progress technological and digital transformation to support the success of a NUE target

Threats to achieving a NUE target

  • Climate change affects the sources and sinks of N
  • Legislative delays
  • Incorrect implementation of measures

PESTLE

Setting NUE and other N targets are subject to a range of enablers and barriers. Therefore, a political, economic, social, technical, legal, and environmental (PESTLE) analysis was undertaken to assess the feasibility of setting a NUE target for Scottish agriculture, again, with the limitation that the analysis was based on N, GHG and climate related rather than NUE specific targets. The PESTLE assessment took place following the SWOT analysis to ensure the findings from the SWOT were assessed and, if relevant, included into the PESTLE categories.

 

Enablers

Barriers

Political

  • Socioeconomic, cultural and health considerations can be used to inform policies. In the context of N this includes impacts on air and water pollution, climate, farmer incomes and biodiversity.
  • The introduction of government policy incentivises uptake of mitigation measures by providing focus and direction
  • NUE increase is complimentary with other economic, environmental, health and climate policy objectives
  • Regulatory instruments (pollution standards and ceilings/fertiliser use limits/ BAT)
  • Negative experiences in other countries who are dealing with a similar challenge (E.g., farmer protests following the Dutch government proposals to tackle N emissions)
  • Lack of clarity on synergies with other policies
  • Pushback on measures seen to reduce productive output in terms of food production

Economic

  • Optimal use of fertiliser saving farmer’s money
  • Capital grants or support schemes can help shoulder on-farm costs and encourage uptake of the more expensive mitigation measures (e.g. specialised spreading equipment)
  • Mitigation measures are expected to span a wide range of activities and may result in net benefits to farmers (e.g., improvement in farm profitability)
  • Many mitigation measures are low cost and available to farmers
  • Policy levers available to encourage optimal use of fertiliser
  • Lack of incentives
  • Mitigation measures are expected to span a wide range of activities and may result in net costs to farmers
  • Upfront investments required to implement some new technologies and strategies to reduce emissions
  • Recurring costs of mitigation measures

Social

  • Health benefits e.g., controlling N pollution will lower nitrate concentrations in drinking water
  • Public drive and increasing interest in climate, health and environment can influence policy (increasing interest from public)
  • Increase in value of farm produce
  • Current lower levels of fertiliser use (due to high prices) can complement a NUE target and contribute to an ambitious target
  • Communicative instruments (extension services/ education, awareness and persuasion/ co-operative approaches)
  • A target with a non-mandatory approach will require buy-in from farmers
  • Potential impact on output if N is changed without proper strategies in place e.g. removing all fertiliser use (reduced yields/switching effect due to challenges of continuing to produce products profitably)
  • Perception of potential for decreased yield/ production security

Technical

  • Technology and measures exist to improve NUE, and solutions continue to be developed through research
  • The SNBS annually monitors and measures Scottish agriculture’s NUE
  • Training and advice to farmers, feed companies and other support services would support NUE increases
  • Many farmers are not aware of why and how to improve N use
  • Monitoring and measuring NUE target success at sub-sector level (i.e. for different farming systems) is not currently possible at a central level

Legal

  • Legislation to support a NUE target exists e.g., Cleaner Air for Scotland Strategy Plan 2021, Scotland’s Agricultural Reform Route Map
  • The objectives of existing legislation would be supported (air and water quality, farmer incomes, biodiversity and human health)
  • Farmers may not comply with regulatory requirements
  • A NUE target must fit in with other environmental legislation (e.g., integrate with The N directive, National Emissions Ceiling Directive, Drinking Water Directive etc.)
  • N limiting targets (N budgets) may lead to legal challenges
  • Time taken to create and process legislation for a N target can be longwinded and uncertain

Environmental

  • Measures related to N mitigation can also mitigate other pollutants
  • A NUE target may have other indirect positive benefits to the environment e.g., improvements to air and water quality
  • Unintended consequences of mitigation measures, e.g. decreased productivity of agriculture, displacing some production and impacts to another place
  • Pollution swapping (e.g. decreased NH3 emission leading to more retained N in soil with increased N2O emission)

Appendix H: Worked example

To aid in understanding the approach taken to calculate the impact of each measure on the NUE worked example, for slurry acidification has been presented below.

Slurry acidification can reduce the NH3 volatilisation at the storage stage by 75% for dairy, beef and pigs. It will also reduce N2O at the spreading stage by 23%. This measure cannot be applied on all managed livestock manure, and can be applied only where slurry is stored in tanks. Approximately, 41%, 4%, and 38% of dairy, beef, and pig excreta is on a slurry system, respectively, and approximately 50% is in slurry tanks rather than lagoons, for each livestock type. Therefore, this measure can be applied to approximately, 21%, 2%, and 19% of all dairy, beef, and pig excreta.

The relevant flows with the SNBS for these two impact values are N2O emissions from animal husbandry (including manure management), with a value of 0.92 kt N yr-1, and NH3 from housing and storage of manure, with a value of 10.5 kt N yr-1.

These flow values represent the absolute quantity of N transferring from the excreta pool to the atmosphere, for all livestock and storage types. Of total livestock units in Scotland, approximately 42% are beef, 11% are dairy, and 12% are pigs.

The uptake levels of this measure in 2030 is estimated to be 7%.

The current uptake is assumed to 0%.

The applicability of this measure on dairy is:

Portion of livestock that are dairy animals * portion of dairy excreta suitable for acidification

0.11 * 0.21

= 0.0228

Therefore, the impact of slurry acidification on the dairy sector is:

Applicability * (1-Current Uptake) * Impact Value * 2030 Uptake

0.0228 * (1-0.00) * -0.75 * 0.07

= -0.12%

Apply this to the absolute value for dairy from the SNBS:

10.5 * 0.0012

= 0.0126 kt N yr-1

This calculation is carried out for all three livestock types, and for the N2O value. The total N saved is 0.03 kt N yr-1, which is subtracted from the quantity of mineral fertiliser applied to soils:

143.78 – 0.03

= 143.74 kt N yr-1

The NUE is recalculated taking into account the new mineral fertiliser quantity:

(Inputs / Outputs) * 100

(200.08 / 54.48) * 100

= 27.23%

© The University of Edinburgh, 2024
Prepared by Ricardo PLC on behalf of ClimateXChange, The University of Edinburgh. All rights reserved.

While every effort is made to ensure the information in this report is accurate, no legal responsibility is accepted for any errors, omissions or misleading statements. The views expressed represent those of the author(s), and do not necessarily represent those of the host institutions or funders.

ClimateXChange

Edinburgh Climate Change Institute

High School Yards

Edinburgh EH1 1LZ

+44 (0) 131 651 4783

info@climatexchange.org.uk

www.climatexchange.org.uk


  1. N waste is reactive nitrogen (Nr) that is not used in the nitrogen cycle. Higher N waste reduces NUE.



  2. The 2021 total is an adjusted total to consider compliance, meaning the contribution of emissions from non-manure digestate spreading is removed



  3. A NVZ designation limits the total amount of N (from livestock manure) that can be applied to agricultural land in that area. Scottish NVZ designation is reviewed every four years and nitrate concentrations in surface and ground water are measured by The Scottish Environment Protection Agency (SEPA).



  4. N fertilisers are used most commonly in the forms of ammonium nitrate and to a lesser extent urea both as a solid prill (pellet) which is spread using a broadcast spreader.


Land use transformation, and related reductions in greenhouse gas emissions, will be necessary to achieve Scotland’s ambitions to reach net zero emissions by 2045, as well as biodiversity and climate change targets.

A variety of support systems for land use transformation, such as financial support and advice, are already in place.

This study aims to understand how and why land managers engage, or don’t engage, with these support systems, to inform how policy could be best deployed to accelerate the process of change.

Findings

There is substantial evidence for land manager behaviour and decision making that influences engagement with support systems. Their decisions are determined by a range of interacting internal and external factors, primarily related to financial, practical and cultural influences.

  • Overall, the public sector grant-giving support network is logical and straightforward to use.
  • The administrative burden associated with applying to schemes is a barrier to engagement.
  • Land managers often decide whether to engage with support and advice based on confidence in its source. For example, farmers are more likely to trust advisers that have a practical farming background over those from a consulting or academic background.
  • Land managers in Scotland primarily access public funding support. Some access private finance to supplement their income or achieve specific goals.
  • The breadth of support sources is confusing for some land managers.
  • Applicants would prefer administrative simplicity and greater flexibility.
  • Improved accessibility and flexibility will not, by themselves, increase overall engagement with land use change. Other measures, such as attractive payment rates, sufficient technical advice and training and management flexibility, will also be needed.

If you require the report in an alternative format, such as a Word document, please contact info@climatexchange.org.uk or 0131 651 4783.