Geologists revise state's potential for geothermal energyby Dan Kraker, Minnesota Public Radio
DULUTH, Minn. — Minnesota is a cold place. But a new study released Tuesday shows the state has more geothermal energy potential than previously understood.
A 2004 geothermal map of the U.S. showed that Minnesota was much cooler deep underground than neighboring states. But geologists at the University of Minnesota-Duluth were skeptical. Their new analysis shows strong geothermal potential in some areas, mainly in the west-central part of the state.
A geothermal power plant would pump a medium like water or carbon dioxide six kilometers underground.
"We'd go down to a certain depth with one hole, then we'd have a return line that basically takes the hot fluids back up and uses that for the direct creation of electricity," said Don Fosnacht, director of the Center for Applied Research and Technological Development at UMD's Natural Resources Research Institute.
The electricity produced would cost between 4 and 10 cents per kilowatt hour, comparable with wind and other forms of renewable energy, Fosnacht said.
"There is no carbon involved, no fuels that you have to routinely purchase," Fosnacht said. "You drill your hole, you put your media in there, you circulate it, and basically you keep using it over and over again."