Summary:

Biogas production depends on: the type, quantity and quality of administered substrates. Consequence in the substrates supply has a positive effect on stability of the methane fermentation. The selection of the right kind of substrates is very important for the efficiency of biogas plants. The main aim of this thesis was to determine the efficiency of co-substrate used in agricultural biogas plant. Substrates used in biogas plant were: maize silage and pig slurry. The study has also determined the amount of electricity produced and the efficiency of fermenters. The analysis was conducted based on one month of biogas plant operation. The analysis proved that usage of additional substrate (pig slurry) has a positive effect on the yield of biogas. In the days when pig slurry was in use, biogas yield increased. The highest biogas yield per ton of co-substrate was equal to 210 (Nm3). The smallest biogas yield per ton of substrate was 178 (Nm3).