Ball State University has completed its campus-wide ground-source geothermal system, the nation's largest geothermal heating and cooling system, DOE announced on March 20. DOE played a part in the project by providing a $5 million grant through the American Recovery and Reinvestment Act. The Indiana-based university anticipates saving $2 million annually in operating costs and cutting its carbon footprint by nearly 50% with the project.

Launched in 2009, Ball State's geothermal system replaces four aging coal-fired boilers to provide renewable power that will heat and cool 47 university buildings, comprising 5.5 million square feet on the 660-acre campus. To provide heating, geothermal heat pumps use a fluid to transfer heat from the Earth to buildings. For cooling, the pumps remove heat from buildings and transfer it back into the Earth. See theĀ Buildings Technologies Program website.