Environmental assessment of untreated manure use, manure digestion and codigestion with silage maize : Deliverable for the 'EU-AGRO-BIOGAS' project

This report describes the environmental impact of untreated manure use, manure digestion, and co-digestion with silage maize for energy production. The life cycle assessment methodology was used. Environmental indicators included were, global warming potential, energy use, eutrophication, acidification and land use expressed per ton applied product. Digestion of manure and codigestion with silage maize resulted in an improved energy and greenhouse gas balance. However, compared to the use of untreated manure, acidification potentials seemed to increase when digesting only manure and decrease with co-digestion. Overall (co)- digestion of manure and co-substrates presents an opportunity to sustainably produce renewable energy and reduce greenhouse gas emissions. Further analysis is required to fully understand the effects on land use changes when using different co-substrates on a large scale.