U.S. Department of Energy - Energy Efficiency and Renewable Energy
Energy 101: Geothermal Heat Pumps (Video)
An energy-efficient heating and cooling alternative, the geothermal heat pump system moves heat from the ground to a building (or from a building to the ground) through a series of flexible pipe "loops" containing water. In winter, heat from the relatively warmer ground goes through the heat exchanger into the building. In summer, hot air from the building is pulled through the heat exchanger into the relatively cooler ground. Heat pump systems are so efficient that they have proven to lower energy bills by up to 70% over traditional types of heating systems. This video shows how geothermal heat pumps generate clean, reliable, and renewable energy using the heat contained within the earth.
For more information on geothermal technologies from the Office of Energy Efficiency and Renewable Energy, visit the Geothermal Technologies Office website.