Wisconsin college installs biogas CHP plant

By | January 06, 2011

In roughly six months, the University of Wisconsin-Oshkosh will host a unique biogas cogeneration plant that will provide its campus with heat and power.

While the biogas plant itself is being designed by BIOFerm Energy Systems, project partner 2G-Cenergy is responsible for the technology that will convert the biogas to heat and power. Both German companies, BIOFerm and Cenergy have installed hundreds of similar systems in Germany, but this particular system will be unique to the U.S., said Cenergy CEO and President Michael Turwitt. “We have done different biogas projects in the U.S. with typical anaerobic digesters, also landfill operations and wastewater treatment plants, but this is the first dry anaerobic digester plant in the U.S.,” he said. “There are a few more coming in the future, but this will be the first one that will be operational.”

The difference between traditional anaerobic digestion systems and Cenergy’s design is that traditional systems are considered wet and utilize waste streams such as manure, requiring the addition of liquid to facilitate constant movement for fermentation. In contrast, dry systems don’t need the addition of liquid to create a fluid mixture that can be pumped through the system. Rather, dry fermentation works via a batch process in which organic waste is loaded into individual fermenters of the biogas plant on a 28-day cycle.

Construction of the 370 kilowatt-hour facility, which will be owned and operated by UWO, is underway, and when operational will use about 8,000 tons of yard and food waste annually.

Turwitt estimated the entire project, which is being partially funded with a $233,000 grant from Wisconsin Focus on Energy and a $500,000 federal government grant, will cost about $3.5 million. He said the unit should be fully operational by the beginning of May.