Geothermal Energy
Geothermal Energy, heat produced within the earth. The major source of the heat is molten underground rock, or magma. Water near the magma is heated to high temperatures and will rise to the surface as steam or hot water through natural cracks or wells that have been drilled for that purpose. If enough steam is available, it can be used for generating electricity; hot water can be used for heating buildings.
Most of the world's geothermal resources are in areas where magma tends to rise close to the surface, such as in earthquake zones and in regions of past or present volcanic activity. Geothermal areas often have geysers or hot springs.
Geothermal energy is used at a number of sites. It drives electric generators at a northern California site called The Geysers, and at Wairakei, New Zealand. In Reykjavik, Iceland, almost every home is supplied by deep wells with hot water for heating and washing.