How Do Geothermal Heat Pumps (GHP) Work?
Geothermal heat pumps take advantage of the earth’s constant temperature to provide extremely efficient heating and cooling. Standard air-source heat pumps use the outside air temperature to heat and cool a home. A few feet beneath the earth’s surface, the temperature of the ground remains fairly stable year-round, ranging from 45◦F (northern latitudes) to 70◦F (deep south). Like a cave, this ground temperature is warmer than the air above it during the winter and cooler than the air during the summer. Geothermal heat pumps take advantage of these conditions by exchanging heat with the earth through a ground heat exchanger. This allows the GHP to heat, cool, and if so equipped, supply the home with hot water. A GHP system collects the earth’s natural heat through a fluid-filled series of pipes made of copper or plastic that is installed below the surface of the ground. It can also be submersed in a body of water. Fluid circulating in the pipes carries the earth’s heat to the home. In t
