The Contribution of Manure Utilisation in Biogas Plants in Terms of Climate Change

The main source of global CO2 is heat and electricity production, which requires an increase in renewables that cover fluctuating sources. Biogas plants are one possibility, which are already commonly used in the European energy system. This study focuses on the utilisation of raw manure to reduce direct emissions of methane within an advanced and expensive, and a simplified and less expensive plant. Therefore, the environmental impact in terms of CO2 eq emissions of a biogas plant with either subsequent combustion in an internal combustion engine or the direct use of the biogas in a simplified burner are investigated. The analysis shows that the more advanced system yields 493 t CO2 eq, while the simplified one causes 42 t CO2 eq per year. Nevertheless, increasing average annual temperatures generate higher manure credits and thus reduce emissions of both plant options to 726 and -178 t CO2 eq per year, respectively, making the direct biogas usage become more interesting. Thus, both systems hold the potential for savings in terms of improved manure management against the background of climate change.