Geothermal heating simply pumps heat from the earth into your home. A liquid is circulated through a large loop(s) in the ground called a ground loop. While that liquid is traveling through the pipe buried in the ground, it absorbs the heat from the surrounding ground. That liquid then carries the heat to the heat pump, which acts similar to a refrigerator in taking that heat through a refrigerant cycle inside the heat pump, and discharging it to your home heating distribution system (forced air or radiant floors).