Epic Systems Uses Data Center Heat for Geothermal Storage

Epic Systems, a health software company in Verona, Wisconsin, has implemented a geothermal system to manage waste heat from its 3.5 megawatt (MW) data center. Over two decades, the company has drilled approximately 6,100 wells, ranging from 300 to 800 feet deep, to heat and cool about 40 buildings on its campus.

The system's unique aspect is its ability to store heat in the ground during summer and retrieve it months later for winter use. This addresses a common challenge in data center heat reuse, as servers generate heat year-round, while buildings typically require heating for only about four months of the year. Unlike ordinary ground-source heat pumps that extract heat from the earth in winter, Epic's system injects heat into the ground during warmer months.

This approach is distinct from other recent news involving data centers and geothermal energy, such as Google's purchase of geothermal power in Nevada and Meta's contracts in New Mexico. Those projects focus on extracting existing heat from the earth to generate electricity. Epic's method, however, involves storing heat generated by the building itself underground, with the ground acting as a thermal reservoir. The concept highlights the importance of storage for effectively reusing data center waste heat, drawing a parallel to how large snow piles can persist long after smaller ones have melted.