Grass from Road Verges as a Substrate for Biogas Production

Maintenance of urban green infrastructure generates a large amount biomass that can be considered valuable feedstock for biogas production. This study aims to determine the effect cutting time and method substrate preservation on specific methane yield (SMY) grass collected from road verges median strips between roadways in wet (WF) dry fermentation (DF) technology. The was three times growing season, including spring, summer, autumn. biochemical potential (BMP) test performed fresh grass, ensiled without additives, with microbiological additives. In addition, energy potentially produced avoided CO2 emissions were calculated. highest SMY (274.18 ± 22.59 NL kgVS−1) observed spring subjected WF. At same time, lowest CH4 production (182.63 0.48 found digested DF A comparison obtained samples WF technologies revealed higher yields electricity heat affected by cutting, ensilage method, AD Generally, less but more least (469–548 kWh tDM−1) cut DF, while most (621–698 autumn case production, situation reversed. (1.4–1.9 GJ WF, (2.2–2.7 DF. Ensilage decreased almost all cuttings. total reduction may 2400 kg per 1 hectare verges. significant demonstrates use roadside plants should feasible option. Even though co-substrate only, it partially substitute crops reduce area needed purposes. Our results reveal waste technology is stable process. do not affect technology, especially late season used as feedstock, extends decomposition and, therefore, real-life plant.