Geothermal Campus Conversion

Salas O’Brien planned, designed, and implemented all stages of this phased conversion project. creating the largest geothermal system on a higher ed campus in the US. Ball State also became the nation’s first fully electric campus. The system heats and cools 47 buildings. Since its startup in 2014, the University has cut its carbon footprint in half and realized over $2 million in annual energy savings.

Salas O’Brien coordinated all design disciplines, executed LEED Certification, acted as Owner’s Representative during construction, and provided commissioning services. The system includes two district energy stations, two vertical loop fields totaling 3,383 bores containing 1,000 miles of high-density polyethylene pipe, four 2,500-ton heat pump chillers, and 10 miles of buried distribution piping.

Eliminating four plants that burned 36,000 tons of coal annually, Ball State annually eliminates 85,000 tons of carbon dioxide emissions, 240 tons of nitrogen oxide, 200 tons of particulate matter, 80 tons of carbon monoxide, 1,400 tons of sulfur dioxide, and 3,400 tons of coal ash.

Completion Year



5.6 million square feet

Construction Cost

$83 million


Million Dollars

Annual energy savings

Buried distribution piping