Epic Systems stores data center heat underground in Wisconsin
Epic Systems in Verona, Wisconsin, stores heat from its data center underground to use later in winter.
The company drilled roughly 6,100 wells three hundred to eight hundred feet deep to serve its campus buildings. These wells capture waste heat generated by a 3.5-megawatt facility operating continuously throughout the entire year.
Standard heat pumps usually extract warmth in winter, but this unique system injects heat during summer months instead. The stored thermal energy remains trapped within the rock because the ground material acts as a poor conductor.
Water heated by servers flows through pipes deep underground and warms the surrounding stone before returning to the surface. When winter arrives, the same water retrieves that stored warmth to heat offices and melt snow on sidewalks.
This approach addresses the problem that most buildings only need heating for about four months of the calendar year. Without storage, piping heat directly fails to solve cooling needs during the hot summer season effectively.