A comprehensive new MIT-led study of the potential for geothermal energy within the United States has found that mining the huge amounts of heat that reside as stored thermal energy in the Earth’s hard rock crust could supply a substantial portion of the electricity the United States will need in the future, probably at competitive prices and with minimal environmental impact.

The study shows that drilling several wells to reach hot rock and connecting them to a fractured rock region that has been stimulated to let water flow through it creates a heat-exchanger that can produce large amounts of hot water or steam to run electric generators at the surface.

Unlike conventional fossil-fuel power plants that burn coal, natural gas or oil, no fuel would be required. And unlike wind and solar systems, a geothermal plant works night and day, offering a non-interruptible source of electric power.