Below follow some useful links to organisations within the ground source sector.
Geothermal energy, also referred to as shallow geothermal, is natural heat and cold stored in the underground. In addition a minor fraction of heat flow along the geothermal gradient (from the hot core of the Earth) is added.
The energy is used by a Geothermal Heat Pump (GHP), also called Ground Source Heat Pump, which takes this heat during the heating season at an efficiency approaching or exceeding 400%, and then, if cooling is used, return it during the cooling season. In residential homes however, most common solution is to use a GHP to provide heating and hot water.