Geothermics (geothermal prospecting) is the use of the earth's heat to produce electricity, heat and cooling energy.
Temperatures inside the earth heat the planet’s outer layers and underground water reservoirs. This energy is tapped with the help of wells. For using geothermal energy up to 400 metres deep ("near-surface"), a heat probe combined with a heat pump utilises the different temperature level between the soil and the ambient air. In deeper strata, hot water and steam are obtained for district heating grids or to generate electricity.