A geothermal system consists of an indoor unit and a buried earth loop. The ground remains a relatively constant temperature throughout the year.  Geothermal systems take advantage of this stable temperature by transferring it to underground loops of fluid. The fluid inside these loops is circulated to the unit inside the house, the liquid is compressed and a blower then blows the cool or warm air throughout the house just like a normal heating and cooling system 

The application of geothermal heating/cooling, also known as ground source heat pumps, has been named "the most energy-efficient and environmentally sensitive of all space conditioning systems", by the Environmental Protection Agency. The system's basic concept takes advantage of the earth's constant temperature, approximately 55 degrees, to heat and cool a building. By tapping this steady flow of heat from the earth in the winter, and displacing heat in the earth in the summer, a geothermal heat pump can save homeowners 40 to 70 percent in heating costs and 30 to 50 percent in cooling costs compared to conventional systems.

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