Geothermal Energy

Geothermal energy uses the natural sources of heat inside the earth to produce heat or electricity. Currently, most geothermal energy is produced by steam or hot water from underground. Geothermal power generation produces few emissions and the power source is always available.

There are three geothermal technologies currently in the United States: direct-use systems, the use of deep reservoirs for the production of electricity, and geothermal heat pumps.

In the direct use of geothermal systems, is a well-drilled in a geothermal reservoir, a steady stream of hot water. The water is through the well, and a mechanical system piping, heat exchangers, controls and delivers the heat directly on the intended use. A disposal system then either chilled water or injected underground, which it has a surface storage pond. Geothermal hot water is used for heating buildings and the improvement of crops in greenhouses, crops drying, heating water for fish farms or for industrial processes, in hundreds of locations throughout the country. Geothermal reservoirs for the direct use systems are widespread throughout the western United States. Geothermal power plants convert hydrothermal fluids (hot water or steam) to electricity. The oldest type of geothermal power plant uses steam, accessed through deep wells, drive directly to a turbine to generate electricity. Flash steam plants are the most common form of geothermal power plants in operation today. They use extremely hot water (above 300 degrees F (149 ° C)), which is pumped under high pressure on the generation equipment on the surface.

Estimated temperatures underground at a depth of 6 km. The hot water evaporates and the steam in turn drives turbines to generate electricity. Binary cycle geothermal power plants use water moderate temperatures (100-300 ° F (38-149 degrees C)). The water will evaporate to a second liquid, has a much lower boiling point than water. The vapor from the second fluid is then used to the turbines to generate electricity. California, Hawaii, Nevada, Utah and are currently operating geothermal power plants.