4.2. Co-digestion of multiple feedstock scenarios
Fig. 4 shows the weighted single-score LCIA results for the multiple feedstock co-digestion scenarios analyzed. It is shown that, for both small and large-scale co-digestion scenarios, codigestion of mainly agricultural and food industry residues (Base SS-2; 5.2 pt) and MSW with residues of food industry (Base LS-2;8.6 pt), respectively, were able to achieve highest cumulative damage impact reductions. In contrast, co-digestion of cattle manure with high proportion of energy crops exhibited the highest environmental impacts for both small (Base SS-1) and large-scale (Base LS-1) biogas plants. For small-scale plants, the environmental performance improved from an impact score of 6.1
points for co-digestion of cattle manure with 70% energy crops