Geothermal heat pumps use the heat stored in the earth’s surface to heat homes and buildings. Even in the dead of winter, the temperature not very far below ground remains at a temperature typically in the 50s. Geothermal systems tap into this immense thermal resource. Conversely, this same temperature sink can be used to provide cooling during the summer. It takes electricity to run the heat pumps, but is vastly more efficient than using electricity directly to produce heat or to cool air.