From Biogas Opportunities
Animal and crop wastes are frequently used as a feedstock for anaerobic digesters. Swine and dairy farms, as well as other facilities that handle manure as liquids and slurries, are incorporating biogas recovery systems, including anaerobic digesters that capture and combust biogas to produce alternative fuels, like BioCNG, or generate electricity, heat or hot water. In the US today, there are about 162 agricultural anaerobic digester systems, which produced about 453,000 megawatt-hours (MWh) of energy in 2010, enough to power 25,000 average U.S. homes. Different types of digesters are used depending on the farm’s existing waste management system. These systems can also be expanded to incorporate codigestion (bringing in organic waste materials to boost gas production and generate tipping fees), use of the liquid digestate as fertilizer, and even using manure fibers as bedding material or for other beneficial purposes.