Geothermal Energy 101

Geothermal Energy is made up from the heat inside the Earth. Resources of geothermal energy range from hot rocks found in shallow ground to hot water springs. Also, the heat from the inner core of the earth called “magma” can be used as a source for Geothermal Energy

The shallow part of the Earth’s mantle or “crust” (the Earth's surface), maintains a constant temperature of 50° to 60°F (10° and 16°C). Geothermal heat pumps tap into this heat as a resource to energize commercial and residential buildings. A geothermal system consists of a: heat pump, an air delivery system, and a heat exchanger.

During the winter months, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system. In the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger. The heat removed from the indoor air during the summer can also be used to provide a free source of hot water.

In the United States, most geothermal reservoirs of hot water are located in the western states, Alaska, and Hawaii. Wells can be drilled into underground reservoirs for the generation of electricity. Some geothermal power plants use the steam from a reservoir to power a turbine or a generator, while others use the hot water to boil a “working fluid” that is then vaporized which turns a turbine or generator. Hot water close to the Earth’s crust (normally 10 ft below the surface), can be used solely for heating buildings, greenhouses, drying crops, heating water, as well as pasteurizing milk.

The use of hot dry rocks for a geothermal resource is found at 3 to 5 miles beneath the Earth's surface. The process of Geothermal Energy is quite simple. One pump will inject cold water down a well; circulate it through dry hot fractured rocks, and then another well will suck in the heated water or steam.

Currently, though, there are no commercial applications for Geothermal Energy. Existing technology also does not yet allow recovery of heat directly from magma, the most powerful resource of geothermal energy. Rather, just the steam from it can be used.

If you are interested in using Geothermal Energy, check around your town and find out if it’s accessible. This type of reusable energy is still new and it is pricey, but VERY efficient.

As Always, Keep it Green