To evaluate whether water from a flooded underground coal mine could serve as a sustainable, low-energy cooling source for a proposed data center in the Town of Wise, Virginia. The study was developed in support of a broader regional initiative to attract data center investment to Southwest Virginia by demonstrating the area’s unique infrastructure potential.
The study centered on the Upper Banner Mine, a flooded coal mine located adjacent to a prospective data center site. PCCI developed a preliminary design for a closed-loop system that would circulate naturally cool mine water through plate-frame heat exchangers to absorb heat from the facility’s chilled water loop, then return the warmed water to the mine to dissipate heat into the surrounding geology. The system was sized to handle a 20.8-megawatt thermal load — equivalent to nearly 6,000 tons of refrigeration.
The work spanned hydraulic system design, geotechnical assessment of mine stability, hydrologic analysis of water circulation and residence time within the mine, and a full financial comparison against conventional mechanical cooling systems. Geotechnical review by Marshall Miller & Associates confirmed no fatal flaws in the mine’s structural stability for this application, and the hydraulic design demonstrated that a closed-loop siphon arrangement could dramatically reduce pumping energy requirements.
The study demonstrated that the mine water cooling system is both technically and economically viable, cutting cooling electricity consumption by roughly 90 percent and eliminating the freshwater demand associated with conventional cooling towers. Financial modeling showed the system can deliver investor returns in the range of 8 to 13 percent while generating meaningful annual operating savings for the facility owner — a compelling case for transforming a legacy coal mining asset into critical infrastructure for the modern digital economy.