Geothermal heat pumps also known as ground source heat pumps use the earth's energy to provide heating, cooling and hot water for residential and commercial buildings anywhere in the United States.
Geothermal systems consist of three parts: the ground heat exchanger, the heat pump unit, and the air delivery system (ductwork).
In the winter, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system. In the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger. The heat removed from the indoor air during the summer can also be used to heat water, providing a free source of hot water
Geothermal heat pumps use much less energy than conventional heating systems, since they draw heat from the ground. They are also more efficient when cooling your home. Not only does this save energy and money, it reduces air pollution.
(Source: National Renewable Energy Laboratory (NREL))