The process of distilling whisky creates by-products that can be a feed source for sheep and cattle.
This report looks at the entire lifecycle impacts of using some forms of these by-products in renewable energy, traditional animal feed or concentrated dark grains animal feed.
- All three scenarios were found to have a net beneficial climate change impact, offsetting GHG emissions by avoiding the production of energy, animal feeds and/or fertilisers by other means.
- The renewable energy scenario offset the largest amount of GHG emissions overall.
- While the two animal feed scenarios perform better in certain life-cycle phases, such as capital burdens and material use, the generation of renewable energy avoids a significant amount of carbon through the offsetting of grid electricity and heat.
- The sensitivity of these results to some underlying assumptions was tested during the study:
- it was found that switching the offset cattle feedstock from rape meal to soya bean meal decreases the GWP benefits for the two animal feed scenarios;
- including woodchip co-firing significantly increases the GWP benefits for the renewable energy scenario;
- assuming that any heat produced would offset heavy fuel oil (rather than natural gas) improved the GWP results for all three scenarios to varying amounts.
- However, the overall positioning of the three scenarios was unaffected by the sensitivities modelled; the renewable energy scenario remained the most favourable.