$30,000
It costs millions of dollars and takes years to build. Geothermal heating and cooling is also referred to as ground source heating or geoexchange. This is what you would use at your own home to heat and cool your home. Plastic pipes are inserted into the ground anywhere from 6 to 300 feet.  Geothermal power plants are characterized by high capital investment for exploration, drilling wells, and plant installation, but low cost for operation and maintenance. In 2001, EPRIestimated that capital reimbursement and associated interest account for 65% of the total cost of geothermal power. (8) Capital costs of a combined cycle natural gas power plant, in contrast, only represents about 22% of the levelized cost of electricity produced from the plant, while the fossil fuel cost accounts for 67% . 8.7. How will the cost of geothermal energy compare to the cost of fossil fuel in the future? Costs for geothermal generation at some facilities have decreased to half the original price per kilowatt hour of power in 1980, compared to when the first independent geothermal plants were installed. (8) Capital costs of a combined cycle natural gas power plant, in contrast, only represents about 22% of the levelized cost of electricity produced from the plant, while the fossil fuel cost accounts for 67% . Geothermal plants are capital-intensive, but are relatively cheap to run. Costs range from $0.01 to $0.03 per kilowatt-hour, and can operate at 90% availability or more. Maintenance costs increase if a geothermal power plant operates at greater than 90% availability. This high price is justified, because the maintenance costs are covered by the increased production of the plant. The first geothermal power generator was tested in Italy in 1904. The first large-scale geothermal electric plant in the United States began operation in 1960, operating successfully for 30 years and producing 11 megawatts (MW) of net power. There are many factors that influence the cost of a geothermal power plant. In general, geothermal plants are affected by the cost of steel, other metals and labor, which are universal to the power industry. However, drilling costs may vary as well. (8) Capital costs of a combined cycle natural gas power plant, in contrast, only represents about 22% of the levelized cost of electricity produced from the plant, while the fossil fuel cost accounts for 67% . Next is design of the actual plant. Power plant construction is usually completed concurrent with final field development. The initial cost for the field and power plant is around $2500 per installed kW Operating and maintenance costs range from $0.01 to $0.03 per kWh. Most geothermal power plants can run at greater than 90% availability (i.e., producing more than 90% of the time), but running at 97% or 98% can increase maintenance costs. Geothermal energy is available 24 hours a day, 365 days a year. Geothermal power plants have average availabilities of 90% or higher, compared to about 75% for coal plants. Geothermal power is homegrown, reducing our dependence on foreign oil The initial costs of geothermal energy are high -- wells can cost $1 to $4 million each to drill, and installation of a home geothermal pump system can run as much as $30,000 [sources: REPP, Consumer Energy Center ]. However, a home geothermal energy pump can cut energy bills by 30 to 40 percent and will pay for itself within 5 to 10 years [source: Consumer Energy Center ]. Geothermal energy is considered renewable because the heat is continually replaced. Capital investment can be split into three phases: exploration and drilling, construction of power facilities, and discounted future re-drilling/well stimulation. The capital cost for a geothermal power plant is about $2,500 per kilowatt (kW), whereas operation and maintenance costs range from $0.01 to $0.03 per kWh. The first geothermal power generator was tested in Italy in 1904. The first large-scale geothermal electric plant in the United States began operation in 1960, operating successfully for 30 years and producing 11 megawatts (MW) of net power.
http://www.geothermalgenius.org/geothermal-power http://www.geo-energy.org/geo_basics_plant_cost.aspx http://www.geo-energy.org/geo_basics_plant_cost.aspx http://www.wbdg.org/resources/geothermalelectrictech.php http://www.geo-energy.org/geo_basics_plant_cost.aspx http://energy.gov/eere/geothermal/geothermal-faqs http://science.howstuffworks.com/environmental/energy/geothermal-energy2.htm http://www.wbdg.org/resources/geothermalelectrictech.php
cost of a geothermal power plant for the home