Geothermal energy in the United States was first used for electric power production in 1960. The Geysers in Sonoma and Lake counties, California was developed into what is now the largest geothermal steam electrical plant in the world, at 1,517 megawatts. Other geothermal steam fields are known in the western United States and Alaska. Geothermally generated electric power can be dispatchable to follow the demands of changing loads. Environmental impact of this energy source includes hydrogen sulfide emissions, corrosive or saline chemicals discharged in waste water, possible seismic effects from water injection into rock formations, waste heat and noise.
The Geysers is the world's largest geothermal field, containing a complex of 18 geothermal power plants, drawing steam from more than 350 wells, located in the Mayacamas Mountains approximately 72 miles (116 km) north of San Francisco, California.
The Soda Lakes are two lakes located northwest of Fallon, Nevada. They occupy two basaltic maar volcano craters which may have erupted in the last 1500 years. The larger lake, called Soda Lake or Big Soda Lake, is somewhat elongated, stretching 2 kilometers (1.2 mi) in length. The smaller one, Little Soda Lake, is 200 meters (660 ft) across. Considered to be a single volcano, the combined craters are young enough that future activity can't be ruled out. A geothermal power plant is located on the northeast flank of the volcano.
An enhanced geothermal system (EGS) generates geothermal electricity without the need for natural convective hydrothermal resources. Until recently, geothermal power systems have exploited only resources where naturally occurring heat, water, and rock permeability are sufficient to allow energy extraction. However, by far most of geothermal energy within reach of conventional techniques is in dry and impermeable rock. EGS technologies enhance and/or create geothermal resources in this hot dry rock (HDR) through a variety of stimulation methods, including 'hydraulic stimulation'.
The Te Huka Geothermal Power Station, also known as Tauhara One, is a 23 MW binary cycle geothermal power station situated near Taupo, New Zealand. The power station is operated by Contact Energy.
Ngatamariki is a geothermal power station commissioned in 2013 and operated by Mercury Energy. It is located approximately 17 km north east of Taupo and was constructed well under the budget of $475 million.
Ormat Technologies Inc. is an international company based in Reno, Nevada, USA. Ormat supplies alternative and renewable geothermal energy technology. The company has built over 190 power plants and installed over 3,200 MW. As of January 2021 it owns and operates 933 MW of geothermal and recovered energy based power plants. Ormat has supplied over 1000 turbochargers worldwide: North America, South America, Europe, Australia, and Asia. The company's products also include turbines, generators, and heat exchangers.
The Olkaria Area is a region located immediately to the south of Lake Naivasha in the Great Rift Valley of Kenya, Africa. It is geothermally active and is being used to generate clean electric power. The region has an estimated potential of 2,000 MW. This is almost double the maximum daily electricity peak demand recorded in 2008/2009 for the entire country.
The Stillwater GeoSolar Hybrid Plant is a combined 61 MW solar energy and geothermal power plant in the U.S. state of Nevada. Located 12 miles (19 km) NE of Fallon, near Stillwater, the site includes a 26MW solar photovoltaic plant and a 2MW solar thermal plant that were added to a 33MW geothermal plant.
The Gümüşköy Geothermal Power Plant is an air-cooled Organic Ranking Cycle (ORC) system geothermal power plant located at Gümüşköy village of Germencik district in Aydın Province, Turkey. The power plant feeds from the 182 °C Gümüşköy Geothermal Reservoir, which was discovered with the GK-1 geothermal well in October 2008.
Most of Kenya's electricity is generated by renewable energy sources. On 13 December 2019, Kenya brought online a new 50 megawatt (MW) solar plant in Turkana at the cost of $129 million, bringing her renewable energy to 90% of its power mix. With an installed power capacity of 2,336 MW, Kenya generates 870 MW hydroelectric power, 706 MW geothermal power, 253.5 MW thermal power and the rest from other sources. Kenya is the largest geothermal energy producer in Africa and was also the first geothermal-producing state in Africa when Olkaria I Power Station was commissioned in 1981, generating 45 MW. Seventy three percent (73%) of Kenyan households have electricity access. Currently, Kenya is building Olkaria I Unit 6 which will produce an additional 83 MW to the grid making it the 7th largest geothermal power producer in the world. Additionally, Kenya has the largest wind farm project in Africa with the Lake Turkana Wind Project Power Project. In March 2011, Kenya became the first country in Africa to open a carbon exchange, presenting 17 projects for registration to the U.N. Kyoto Protocol’s Clean Development Mechanism executive board. Kenya is also a signatory to the Paris Agreement and targets to reduce carbon emissions by 30% below business as usual by 2030 as determined in the Nationally Determined Contribution (NDC). The Renewable Energy Directorate under the Ministry of Energy is responsible for research and development of renewable energy technologies.
U.S. Geothermal, Inc. was an independent geothermal energy company focused on the development, production and sale of electricity from geothermal energy, until its acquisition by Ormat Technologies in January 2018. The company operates three geothermal plants in the United States. located in Idaho, Oregon and Nevada, and is developing power plants in California, Nevada, Oregon as well as in Central America in the Republic of Guatemala.
The Menengai I Geothermal Power Station is a 35 MW (47,000 hp) geothermal power plant under construction in Kenya.
The Puna Geothermal Venture (PGV) is a geothermal energy power plant on the island of Hawaii, the largest island in the state of Hawaii. The plant was shut down shortly after the start of the May 2018 lower Puna eruption, and resumed power generation in November 2020. The eruption had caused lava to flow over a PGV power substation, a warehouse and at least three geothermal wells that had been preventatively quenched and capped when lava fountains erupted nearby, eventually also cutting off road access.
The McGinness Hills Geothermal Complex is a complex of 3 geothermal power stations located in a valley between the Toiyabe Range and Simpson Park Range in Lander County, Nevada. It is the largest geothermal complex in Nevada and the fourth largest in the United States.
The Mammoth Geothermal Complex is a complex of 3 geothermal power stations located at Casa Diablo Hot Springs about 3 miles (4.8 km) east of Mammoth Lakes, California. The complex is owned by Ormat and operated by its subsidiary Mammoth Pacific.
