Biogas production is generally regarded as a very sustainable practice that can guarantee high GHG savings when used for electricity generation. However, sustainability is strongly influenced by many factors, such as the choice of feedstock and operational practices. This paper analyses the impact of several criticalities on the GHG emissions of biogas production. The analysis is based on a biogas plant producing electricity via a CHP engine. The first critical point is the choice of feedstock. Two substrates are analysed either individually or co-digested: maize and manure. In the case of manure, the residues of digestion and the avoided emissions from manure storage and field application are taken into account. This results in high GHG savings compared to the reference system of producing electricity from the European mix. When maize is used as a substrate, all emissions from cultivation have to be accounted for. Co-digestion is combining the advantages of both substrates. A second criticality analysed is the digestate storage. The environmental impact analysis shows that a substantial reduction of GHG emissions can be achieved with closed storage. The biogas pathways, though, have worse environmental performances in eutrophication, terrestrial ecotoxicity and particulate matter potential.

BOULAMANTI Aikaterini;  DONIDA MAGLIO Sara;  GIUNTOLI Jacopo;  AGOSTINI Alessandro; 

2013-01-24

ETA Florence

JRC68886

978-88-89407-54-7,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC68886,