Biogas and ethanol potentials in selected biomasses for organic farming

Summary

The production of bioenergy in organic agriculture (OA) can reduce its dependency on fossil fuels and decrease greenhouse‐gases (GHG) emissions; consequently increasing the sustainability of organic farming. Different biomasses were characterized biologically and chemically for their biogas and bioethanol potential at organic farms in Denmark. Batch experiments indicated methane yield [GJ/ha]: 260.7 (fresh maize), 272.7 (maize silage), 127.1 (fresh rye), 169.7 (rye silage), 161.7 (dried rye), 110.5 (fresh clover), 117.8 (clover silage), 72.3 (dried clover), and 41.1 (dried vetch). Theoretical ethanol yield [GJ/ha] showed: 119.8 (fresh maize), 109.2 (maize silage), 36.9 (fresh rye), 39.9 (rye silage), 84.7 (dried rye), 28.9 (fresh clover), 24.4 (clover silage), 32.7 (dried clover), and 18.8 (dried vetch). The continuous biogas trials with maize silage resulted in 86% of yield of the batch experiments. All of the raw materials were suitable for biorefinery at the organic farm.