EN
The aim of this study was to determine the possibility of increasing the efficiency of biogas production from perennial grasses by their co-fermentation with maize or waste from the agro-food industry. Biomass of miscanthus, Spartina, switchgrass, and big bluestem was harvested on October (second harvest, autumn regrowth) and ensiled. Silages were made also from sugar beet pulp and particular grasses mixed with maize or apple pomace in the weight ratio of 50:50. The silages produced were of good quality. The methane fermentation of silages from grasses blended with maize or particular waste enabled achieving from a few to several dozen percent higher biogas production compared to the mono-fermentation of grass silages. It was concluded that co-digestion of perennial grass silages with apple pomace or beet pulp is an useful method for post-production waste utilization. Moreover, using perennial grasses for biogas production as blends with maize affords an opportunity for the partial replacement of maize as the main substrate with no loss of biogas and methane yield