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Flash stream power is the most common type of geothermal power. This is because the hot water from the earth can be reused to produce more steam. The hot water is pumped up to the surface of the earth where its pressure is lessened and it is separated into steam and cool water. The steam is then collected and used for electricity, and the cooler water is pumped back down to the hot area to continue in the cycle.<ref>http://www.technologystudent.com/energy1/geo4.htm</ref>. | Flash stream power is the most common type of geothermal power. This is because the hot water from the earth can be reused to produce more steam. The hot water is pumped up to the surface of the earth where its pressure is lessened and it is separated into steam and cool water. The steam is then collected and used for electricity, and the cooler water is pumped back down to the hot area to continue in the cycle.<ref>http://www.technologystudent.com/energy1/geo4.htm</ref>. | ||
[[picture]] | [[picture]] | ||
Iceland's very first geothermal plant is a flash steam plant. The Bjarnarflag Geothermal Power Plant is located in North Iceland,and was built in 1969. Bjarnarflag takes the steam produced from the hot water in the ground to produce 3 megawatts of electricity. | Iceland's very first geothermal plant is a flash steam plant. The Bjarnarflag Geothermal Power Plant is located in North Iceland,and was built in 1969. Bjarnarflag takes the steam produced from the hot water in the ground to produce 3 megawatts of electricity. The water that is separated from the steam in this plant is used to heat the fresh water used for district heating in Bjarnarflag<ref>http://www.mannvit.com/GeothermalEnergy/GeothermalPowerPlants/GeothermalProjectBjarnarflag/</ref>. | ||
[[picture]] | [[picture]] | ||
===Binary Cycle=== | ===Binary Cycle=== | ||
Revision as of 02:10, 14 June 2010
Background
Geothermal energy is the energy that can be harnessed using the heat that occurs naturally in the Earth. This heat can be found in volcanoes, hot springs, and geysers [1]. The high temperatures range from 225º F- 600º F [2] and occur in these areas due primarily to the decay of radio-active isotopes that occur within the rocks in the Earth's crust [3]. The surrounding ground water can then be heated, or water can be pumped into the hot areas to produce steam. This steam is what is captured to be used to create electricity through a turbine system.
Types and/or methods
There are three common types of geothermal power: dry steam, flash steam, and binary cycle. Dry steam uses the steam directly from the earth, flash steam pumps water into the hot areas to boil the water and create steam, and binary cycle uses a secondary fluid to power a generator[4].
Dry Steam
Power from dry stream geothermal plants is found directly from the Earth. The natural steam that is created from the geysers in the earth is channeled directly into a turbine that powers a generator. These systems are very rare; not many places on Earth contain enough natural energy in the the steam produced to provide sufficient power[5]. picture The only dry stream power producer that is located in the United States is in California. In the Mayacamas Mountains, just north of San Francisco, The Geysers generates a net capacity of about 725 megawatts of electricity - enough to power 725,000 homes, or a city the size of San Francisco[6]. picture
Flash Steam
Flash stream power is the most common type of geothermal power. This is because the hot water from the earth can be reused to produce more steam. The hot water is pumped up to the surface of the earth where its pressure is lessened and it is separated into steam and cool water. The steam is then collected and used for electricity, and the cooler water is pumped back down to the hot area to continue in the cycle.[7]. picture Iceland's very first geothermal plant is a flash steam plant. The Bjarnarflag Geothermal Power Plant is located in North Iceland,and was built in 1969. Bjarnarflag takes the steam produced from the hot water in the ground to produce 3 megawatts of electricity. The water that is separated from the steam in this plant is used to heat the fresh water used for district heating in Bjarnarflag[8]. picture
Binary Cycle
Description example (greater than 360º F)
Utilized areas
Under-utilized areas
Further reading
References
- ↑ http://iceland.ednet.ns.ca/schedule.htm[[1]]
- ↑ http://www.energysavers.gov/your_home/electricity/index.cfm/mytopic=10470[[2]]
- ↑ Duffield, Wendell A. and Sass, John H. Geothermal Energy—Clean Power From the Earth’s Heat. U.S. Geological Survey: Circular 1249 [[3]]
- ↑ http://www.energysavers.gov/your_home/electricity/index.cfm/mytopic=10470 [[4]]
- ↑ http://www.daviddarling.info/encyclopedia/D/AE_dry_steam_geothermal_plant.html[[5]]
- ↑ http://www.geysers.com/
- ↑ http://www.technologystudent.com/energy1/geo4.htm
- ↑ http://www.mannvit.com/GeothermalEnergy/GeothermalPowerPlants/GeothermalProjectBjarnarflag/