You might not realize it, but beneath our feet lies a source of heat that can be tapped to provide heating and cooling to both residential and commercial buildings, replacing current, large-scale systems with a renewable and domestically sourced energy. The application, Deep Direct-Use (DDU), is an emerging technology that has been underutilized in the U.S., and if feasible, could result in greater opportunities for geothermal resource development and high energy cost savings throughout the country
read more at: https://energy.gov/eere/articles/using-deep-geothermal-heat-and-cool-buildings-and-reduce-energy-bills