Although considered as a type of renewable energy source (RES), biogas always comes as a bundle of products to the society as a whole. Not only does it provide useful energy, it saves GHG emissions via the substitution effect by replacing fossil fuels and from utilising methane that would have otherwise been emitted into the atmosphere through the decomposition of organic matter. In addition, contribution to GHG savings comes from replacing fossil fertilizers with organic fertilizer – digestate – a byproduct from biogas production.
Biogas plants using mainly feedstock from agriculture represent the most complex layout for generation of renewable energy. Biogas produced from agricultural feedstock affects RES targets, Kyoto targets, agricultural practice and socio-economic issues of a rural community.