University of Wisconsin-Oshkosh
IN-24: Innovation A

The Wet Anaerobic Biogas System at the Rosendale Dairy in Rosendale, Wisconsin is a project of the University of Wisconsin Oshkosh, the UW Oshkosh Foundation, MilkSource (owner of the Rosendale Dairy), BIOFerm ™ Energy Systems, and the Viessmann Group of Germany. The Rosendale Dairy Biogas System processes 146,000 tons of manure annually from 8,500 cows on Wisconsin’s largest dairy to produce methane rich biogas. The methane is then burned in an internal combustion engine to generate electricity from a 1.4 MW generator. The unit has the capacity to generate electricity equal to 40% of campus power use and an additional equal amount of thermal energy. Before the digester was built, the methane produced from the manure escaped directly into the atmosphere. Given that molecule for molecule methane (CH4) has a much greater global warming potential (GWP) than carbon dioxide (CO2)—approximately 100 times more than CO2 over a 20 year period—the CO2 equivalent (CO2e) emissions is quite high. UW Oshkosh engaged Camco Clean Energy to assist with the sale of carbon credits on the California cap-and-trade carbon market. Camco secured a contract with British Petroleum, whereby BP will buy the CO2e emissions credits for 10 years. In the first year, the digester produced 28,911 tons of CO2e by destroying the methane from the digester. The project generated $157,415.86 for the UW Oshkosh Foundation after costs. The check was received in November 2016. It is expected that the project will produce closer to $200,000 dollars in the second year. In an interesting coincidence, the amount of methane destroyed and sold as CO2e credits approximates the amount of CO2 emissions associated with the university’s scope 1 and scope 2 emissions. Once the debt for the digester is retired, campus will be in a position to internalize the carbon benefits and apply them to its climate neutrality goals.