Geothermal heat pumps, also called ground-source heat pumps, take advantage of the fact that the earth, just a few feet below the surface, maintains a much more constant year-round temperature than the air. It can therefore be used to provide a heat source in the winter and a heat sink in the summer. Geothermal heat pumps work by circulating a fluid underground through long loops of pipe. The heat pump itself is located indoors and uses a basic refrigeration cycle (evaporation, compression, condensation, and expansion) to transfer heat from the ground to the house in the winter, and from the house to the ground in the summer. Geothermal heat pumps use some similar technology as air source heat pumps, but they are distinctly different in many ways. To learn more about their differences, visit Energy Sage's information on these two types of heat pumps. We share more information on air-source heat pumps on our Efficiency and Electrification page.
What size system do I need?
Determining the appropriate size for a geothermal heat pump system will depend on the size of the building it will be heating and cooling, how efficient the building insulation system is, and factors such as the soil type and the space you have for a system. Your geothermal installer will be able to assess your building and discuss what size may best meet your needs.
How much will it cost?
The cost of a geothermal heat pump system will depend on your home's energy use, lot size, and soil conditions with an expected price range of $10,000 and $30,000 before incentives. One of the best ways to ensure your geothermal heat pump pencils out financially is to invest in energy efficiency measures that improve your home's insulation. To learn more, see our resources on Efficiency and Electrification.
What incentives and tax credits are available?
There are several options for geothermal systems. Visit our Financing and Incentives page for more information on your options.
Where can I find an installer?
The column on the right hand side of this page lists a number of installers operating in Montana. These companies are all MREA members! You can also visit our full Installer Directory for an interactive map of installers.
Where can I find more information?
- Montana Green Power Geothermal Heat Pump Page
- Geothermal Heat Pumps - US Department of Energy
- Montana State University Extension E3A Ground Source Heat Pump Fact Sheets
- All about geothermal heat pumps - Energy Sage
Photo credit (this page): Alaska Center for Energy and Power