What is Geothermal Energy?
For our purposes, when we say geothermal energy we are referring to the renewable and sustainable power source that comes from the heat generated by the earth. This heat derives from the original formation of our planet, from the decay of natural minerals and from the solar energy regularly captured and absorbed by the Earth.
From earliest times, people have used geothermal water that flowed freely from the earth's surface as hot springs. The oldest and most common use was, of course, just relaxing in the comforting warm waters. But eventually, this "magic water" was used (and still is) in other creative ways. The Romans, for example, used geothermal water to treat eye and skin disease and, at Pompeii, to heat buildings. As early as 10,000 years ago, Native Americans used hot springs water for cooking and medicine. For centuries the Maoris of New Zealand have cooked "geothermally," and, since the 1960s, France has been heating up to 200,000 homes using geothermal water.
Today we drill wells into the geothermal reservoirs to bring the hot water to the surface. Once the hot water and/or steam travels up the wells to the surface, they can be used to generate electricity in geothermal power plants or for energy saving non-electrical purposes such as geothermal heat exchange. [Geothermal Education Office]
