where does the heat from geothermal energy come from
Geothermal heating Geothermal energy originates from the heat retained within the Earth since the original formation of the planet, from radioactive decay of minerals, and from solar energy absorbed at the surface.[2] Most high temperature geothermal heat is harvested in regions close to tectonic plate boundaries where volcanic activity rises close to the surface of the Earth. In these areas, ground and groundwater can be found with temperatures higher than the target temperature of the application. However, even cold ground contains heat, below 6 metres (20Â ft) the undisturbed ground temperature is consistently at the Mean Annual Air Temperature[3] and it may be extracted with a heat pump.