Biogas Production in Northern Germany - Status Quo and Potential Environmental Effects

摘要

Energy crop production is promoted in several European member slates by additional subsidies, which may lead to a food-fuel competition for productive land. Energy efficiency (EE) therefore represents a crucial determinant of sustainable bioenergy production systems. In Germany, biodiesel from rapeseed represents a main pathway of bioiuel production from arable land. With respect to EE, however, it is outcompeted by biogas. Anaerobic digestion of slurry and crops has evolved as an energy efficient alternative, especially when equipped with power-heat coupling, and in 2007 the number of plants has increased to over 3,700. As a consequence, the acreage of maize, which is the dominating co-substrate for fermentation increased substantially. Recently, some criticism was voiced concerning the sustainability of energy crop production. The objective of the present study therefore was (i) to monitor the status quo of biogas production in the state of Schleswig-Holstein (Northern Germany) in terms of substrate acreage and use of digestion residues and (ii) to evaluate the situation with respect to its environmental effects.