Having a geothermal heating system installed in your home means that you will actually be able to heat your home with heat extracted from the ground. If this sounds a bit preposterous to you, you are certainly not alone. But this type of home heating does actually work and the technology is not actually that much different from what is used in a standard heat pump system.
Regular heat pumps are able to remove heat from the outdoor air and transfer it into your house to maintain a comfortable temperature in the winter. You may think that there is no heat in the outdoor air in the winter, but that is not actually the case.
Air contains a substantial amount of heat even at very cold temperatures, and heat pumps are able to work quite well, particularly when the outdoor temperature is above freezing. Conveniently, the same process used to heat your house in the winter can be reversed in the summer to extract heat from the indoor air, providing you with a year round home comfort solution.
Geothermal heating works in much the same way, except that geothermal heat pumps extract heat from the ground rather than the air. In order to accomplish this, a loop of pipes is installed in the ground near your house and your geothermal heating system will pump a liquid, generally either antifreeze or water, through those pipes.
As it passes through the pipes, the liquid will absorb heat from the ground and carry it back to a heat exchanger within your house. At that point, the heat from the liquid will be released into air, which is then blown throughout your house.
And just as conventional heat pumps can cool your house in the summer by removing heat and pumping it outside, so too can geothermal heating systems. They do this simply by letting the liquid flowing through the pipes absorb the heat from inside air and then release it into the ground as it travels through the pipe loop below your house.
Because the ground is never as cold in the winter or as hot in the summer as the air, geothermal heat pumps are actually able to work effectively in more extreme conditions than many traditional heat pumps. However, because they require an entire system of pipes to be installed underground, they can be quite a bit more expensive initially as well.