Where does geothermal energy comes from?

Geothermal energy comes from the earth's core. The heat from this comes from when the earth was first formed. Compression and contraction of the earth by our lunar and solar orbits, radioactive decay and solar energy help to maintain the core's temperature.

Home Geothermal Units:

Outdoor temperatures fluctuate with the changing seasons but underground temperatures don't. Four to six feet below the earth's surface, temperatures remain relatively constant year-round. A geothermal system, which typically consists of an indoor unit and a buried earth loop, capitalizes on these constant temperatures to provide "free" energy. In winter, fluid circulating through the system's earth loop absorbs stored heat and carries it indoors. The indoor unit compresses the heat to a higher temperature and distributes it throughout the building. In summer, the system reverses, pulling heat from the building, carrying it through the earth loop and depositing it in the cooler earth.

The Department of Energy (DOE) and the Environmental Protection Agency (EPA) have both endorsed Geothermal Heat Pump systems as among the most energy efficient, environmentally clean, and cost effective systems for temperature control.

Geothermal energy comes from the heat at the centre of the earth. It is the only form of energy on earth that does not come from the sun.