Energetic and Economic Aspects of Biogas Plants Feed with Agriculture Biomass

The aim of this paper was to determine the energetic and economic aspects of a 499 kW power biogas plant powered by substrates in three different scenarios: typical arable crops (maize silage), dedicated energy crops (sorghum silage) and agricultural waste biomass (maize straw). The obtained results show that methane productivity of tested substrates is closely connected with its dry matter content– which was especially significative in case of pig slurry (only 1.30 $\mathrm{m}^{3}\mathrm{C}\mathrm{H}_{4}$/Mg of fresh matter). In consequences methane productivities of tested substrates had strong influence on its masses needed for feeding planned biogas plant (from 11,250 Mg to 20,430 Mg). The research have shown the big differences of the substrates costs in analyzed scenarios: the most costly scenario II was over 180 kEuro more expensive than III scenario. Taking into account 15 years period of guarantied subsidies in Poland, this difference can reach in total 2.71 mln Euro.