Geothermal power is energy generated from heat stored in the earth, or the collection of absorbed heat derived from underground.
Almost everywhere, the upper 10 feet of Earth's surface maintains a nearly constant temperature between 50 and 60°F (10 and 16°C). A geothermal heat pump system consists of pipes buried in the shallow ground near a building, a heat exchanger, and ductwork into the building. In winter, heat from the relatively warmer ground goes through the heat exchanger into the house. In summer, hot air from the house is pulled through the heat exchanger into the relatively cooler ground. Heat removed during the summer can be used as no-cost energy to heat water.
There are also different types of water-source heat pumps. A variety of products are available, for both residential and commercial applications; there are water-to-air heat pumps, water-to-water heat pumps and hybrids between the two. Some manufacturers are now producing a reversible heat pump for chillers also.
According to the National Renewable Energy Laboratory, Nevada ranks second in geothermal resources among the lower 48 states.
The system cost are returned in energy savings in 5–10 years. System life is estimated at 25 years for the inside components and 50+ years for the ground loop. There are approximately 50,000 geothermal heat pumps installed in the United States each year.
Upcoming Geothermal Energy Association Event 2009
October 4-7, 2009: Geothermal Energy 2009 Conference and Expo, Peppermill Resort and Casino, Reno, NV