Future European biogas: Animal manure, straw and grass potentials for a sustainable European biogas production

Biogas is expected to play an important role in reaching the future energy policy targets of the European Union (EU). The sustainability of biogas substrates has however been recently critically discussed due to the increasing shares of agricultural land used for energy crop production.The aim of this study was to project and map the biomass and biogas energy potential from a selection of potentially sustainable agricultural residues, which have been documented to improve in biogas yields when co-digested in biogas production, for the EU28 in year 2030. The investigated types of residual biomasses were animal manure, straw by-products from cereal production, and excess grass from rotational and permanent grasslands and meadows. The biogas energy potential from the investigated biomass was projected to range from 1.2·10³ to 2.3·10³ PJ y^-1 in year 2030 in the EU28, depending on the biomass availability. Alone the biogas energy potential projected in the scenario representing low substrate availability corresponds to a doubling of the European biogas production in 2015. The results shows that sustainable alternatives to the use of maize are present in all the member states of the EU28 to an extent that is sufficient to ensure a continuous progressive development of the European biogas sector.