Right. You need an article. Because apparently, the collective knowledge of humanity is insufficient until it's been filtered through my specific brand of cosmic weariness. Don't get used to this.
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Thermal energy generated and stored in the Earth
This article is about the monumental thermal energy generated and stored deep within the earth. If you're looking for information about the glorified air conditioners people bury in their backyards, see ground source heat pump.
Steam, the ghost of boiled rock, rising from the Nesjavellir Geothermal Power Station in the dramatic, unforgiving landscape of Iceland. The industrial sprawl of the Imperial Valley Geothermal Project near the tragically misplaced Salton Sea, California.
Part of a series on the Sisyphean task of Renewable energy
• Biofuel
• Biogas
• Biomass
• Geothermal energy
• Nuclear power proposed as renewable energy
• Topics by country and territory
• v • t • e
Geothermal energy is the thermal energy humanity has the audacity to extract from the Earth's crust. This planetary furnace is a cocktail of primordial heat left over from the violent formation of the planet and the incessant, slow-burning fire of radioactive decay from deep within its core. For millennia, we have been tapping into this deep heat, first for basic survival and comfort, and more recently, to power our insatiable electrical grid.
Geothermal heating, which involves little more than channeling water from hot springs, is an ancient practice. It has been used for bathing since the Paleolithic era—proving that even our earliest ancestors appreciated a good soak—and for sophisticated space heating since the Roman Empire decided cold floors were beneath them. The leap to geothermal power, the actual generation of electricity, is a far more recent and ambitious endeavor, only truly getting underway in the 20th century. A key advantage, often touted by its proponents, is that geothermal plants churn out power at a constant, predictable rate, utterly indifferent to the whims of weather that plague solar and wind. In theory, the geothermal resources beneath our feet are more than sufficient to satisfy all of humanity's energy demands. In practice, most extraction is predictably clustered in the geologically unstable areas near tectonic plate boundaries.
The cost of generating this power saw a welcome decline of 25% through the 1980s and 1990s. Technological progress has continued to chip away at expenses, making more and more of the Earth's heat a viable resource. In a 2021 estimate, the US Department of Energy pegged the cost of power from a newly constructed plant at a rather competitive $0.05 per kilowatt-hour.
By 2019, the world had managed to install 13,900 megawatts (MW) of geothermal power capacity. Beyond electricity, an additional 28 gigawatts of direct thermal energy were being used as of 2010 for applications like district heating, warming buildings, filling spas, driving industrial processes, desalination, and various agricultural uses. As of 2019, this quietly simmering industry employed roughly one hundred thousand people globally.
The term geothermal itself is a blunt portmanteau from the Greek roots γῆ (gê), meaning Earth, and θερμός (thermós), meaning hot. A description of elegant simplicity for a process of immense complexity.
History
The oldest known pool fed by a hot spring, a relic from the Qin dynasty constructed in the 3rd century BC.
The use of hot springs for bathing is a practice so ancient it dates back to at least the Paleolithic period. The oldest known spa is located at the site of the Huaqing Chi palace in China. In the first century CE, the ever-practical Romans conquered Aquae Sulis, which we now call Bath, Somerset, England. They promptly exploited the local hot springs to engineer elaborate public baths and an ingenious underfloor heating system. The admission fees they charged likely represent the first commercial exploitation of geothermal energy, a transactional relationship with the planet's heat that continues to this day.
The world's oldest geothermal district heating system, found in Chaudes-Aigues, France, has been in continuous operation since the 15th century. The industrial age brought more ambitious applications. In 1827, resourceful industrialists began using geyser steam to extract boric acid from volcanic mud in Larderello, Italy.
In 1892, America’s first district heating system was established in Boise, Idaho, powered directly by geothermal energy. This model was soon replicated in Klamath Falls, Oregon, in 1900. The first building known to use geothermal energy as its primary heat source was the Hot Lake Hotel in Union County, Oregon, starting in 1907. The applications broadened: a geothermal well was used to heat greenhouses in Boise in 1926, and around the same time, geysers were being harnessed for the same purpose in Iceland and Tuscany. In 1930, Charles Lieb developed the first downhole heat exchanger to heat his own home, a direct ancestor of modern systems. By 1943, Iceland was systematically using geyser steam and hot water to heat homes, a practice that would become central to its national identity.
A chart showing the slow, then accelerating, climb of global geothermal electric capacity. The upper red line marks installed capacity, while the lower green line shows what's actually produced.
The 20th century finally saw geothermal energy graduate to a source for electricity generation. On July 4, 1904, Prince Piero Ginori Conti tested the first geothermal power generator at the Larderello steam field. It was a modest success, managing to light four light bulbs—a flickering proof of concept. In 1911, this experiment culminated in the world's first commercial geothermal power plant built on the same site. For nearly half a century, it remained the sole industrial producer of geothermal electricity on the planet, until New Zealand finally built its own plant in 1958. By 2012, the Larderello field was producing some 594 megawatts.
In 1960, Pacific Gas and Electric initiated operations at the first U.S. geothermal power plant at The Geysers in California. The original turbine was a workhorse, lasting over 30 years and producing a steady 11 MW of net power.
The binary cycle power station, which uses a secondary organic fluid, was first demonstrated in 1967 in the USSR and was later introduced to the United States in 1981. This critical innovation allows for the use of much lower temperature resources, as low as 81 °C. Pushing this boundary further, a binary cycle plant in Chena Hot Springs, Alaska, came online in 2006, generating electricity from a record-low fluid temperature of just 57 °C (135 °F).
Resources
A diagram of an enhanced geothermal system: 1:Reservoir 2:Pump house 3:Heat exchanger 4:Turbine hall 5:Production well 6:Injection well 7:Hot water to district heating 8:Porous sediments 9:Observation well 10:Crystalline bedrock. Essentially, a brute-force method of making the Earth give up its heat.
The Earth's core holds a staggering internal heat content of 10³¹ joules (or 3·10¹⁵ TWh), a number so large it's practically meaningless. Roughly 20% of this is residual heat from the chaos of planetary accretion, the cosmic debris slamming together to form our world. The rest is the product of past and ongoing radioactive decay of naturally occurring isotopes. For instance, a 5,275-meter-deep borehole for the United Downs Deep Geothermal Power Project in Cornwall, England, discovered granite with an unusually high concentration of thorium. The slow, steady radioactive decay of this element is believed to be the power source for the rock's extreme temperature.
Deep inside the Earth, the temperature and pressure are immense enough to melt some rock and cause the solid mantle to behave like a slow, thick plastic. Pockets of this mantle convect upward, being lighter than the surrounding material. At the core–mantle boundary, temperatures can exceed 4,000 °C (7,230 °F).
This internal thermal energy perpetually flows to the surface via conduction at a rate of 44.2 terawatts (TW). It is simultaneously replenished by the radioactive decay of minerals at a rate of 30 TW. These power figures are more than double humanity's total current energy consumption from all sources combined. However, most of this energy flux is too diffuse and impractical to recover. In addition to this deep heat, the top 10 meters (33 ft) of the surface are subject to the whims of the sun, heating up in the summer and cooling in the winter.
Beneath this seasonal layer, the geothermal gradient—the rate at which temperature increases with depth—is a relatively consistent 25–30 °C (77–86 °F) per kilometer of depth across most of the world. The conductive heat flux averages 0.1 MW/km². These values spike dramatically near tectonic plate boundaries, where the crust is thinner. They can be further amplified by fluid circulation, through mechanisms like magma conduits, hot springs, and hydrothermal circulation.
The efficiency and, more importantly, the profitability of electricity generation are acutely sensitive to temperature. The most lucrative applications draw from high natural heat flux, ideally from a hot spring. The next best approach is drilling a well into a hot aquifer. Where nature doesn't provide a convenient reservoir, one can be created by injecting water to hydraulically fracture the bedrock. These manufactured systems are known as enhanced geothermal systems.
Estimates from 2010 regarding the potential for geothermal electricity generation vary wildly, from a modest 0.035 TW to an optimistic 2 TW, with the final figure depending entirely on the scale of investment. The higher estimates assume the feasibility of wells drilled to depths of 10 kilometers (6 mi), a significant leap from 20th-century wells that seldom exceeded 3 kilometers (2 mi). Wells of this depth are, however, commonplace in the petroleum industry, which has had far more money to throw at the problem of deep drilling.
Geothermal power
Main article: Geothermal power
Geothermal power is simply the electrical power generated from geothermal energy. The primary methods for this conversion are dry steam, flash steam, and binary cycle power stations. As of 2010, geothermal electricity was being produced in 26 countries.
By 2019, the worldwide installed geothermal power capacity reached 15.4 gigawatts (GW). The United States accounted for the largest share, with 3.68 GW, or 23.86 percent of the global total.
In several countries, geothermal energy is not a niche player but a cornerstone of the national grid. It supplies a significant portion of the electrical power in Iceland, El Salvador, Kenya, the Philippines, and New Zealand.
Geothermal power is classified as a renewable energy source because the rate at which we extract heat is infinitesimal compared to the Earth's total heat content. The greenhouse gas emissions from geothermal electric stations are, on average, 45 grams of carbon dioxide per kilowatt-hour of electricity. This is less than 5 percent of the emissions from a typical coal-fired plant.
Traditionally, geothermal electric plants were constructed exclusively at the edges of tectonic plates, where high-temperature resources are conveniently close to the surface. An ideal site has high subsurface temperatures, high permeability, and a large nearby water reserve to act as a working fluid. The advent of binary cycle power plants and significant improvements in drilling and extraction technology are enabling enhanced geothermal systems to be deployed over a much broader geographical range. Demonstration projects are currently operational in Landau-Pfalz, Germany, and Soultz-sous-Forêts, France. An earlier effort in Basel, Switzerland, was notoriously shut down after it triggered earthquakes. Other demonstration projects are under construction in Australia, the United Kingdom, and the US. In Myanmar, over 39 locations have been identified as capable of geothermal power production, with some conveniently located near major urban centers like Yangon.
Direct use data 2015
| Country | Capacity (MW) 2015 |
|---|---|
| United States | 17,415.00 |
| Philippines | 3.00 |
| Indonesia | 2.00 |
| Mexico | 155.00 |
| Italy | 1,014.00 |
| New Zealand | 487.00 |
| Iceland | 2,040.00 |
| Japan | 2,186.00 |
| Iran | 81.00 |
| El Salvador | 3.00 |
| Kenya | 22.00 |
| Costa Rica | 1.00 |
| Russia | 308.00 |
| Turkey | 2,886.00 |
| Papua New Guinea | 0.10 |
| Guatemala | 2.00 |
| Portugal | 35.00 |
| China | 17,870.00 |
| France | 2,346.00 |
| Ethiopia | 2.00 |
| Germany | 2,848.00 |
| Austria | 903.00 |
| Australia | 16.00 |
| Thailand | 128.00 |
Installed geothermal electric capacity
| Country | Capacity (MW) (2024) | % of national electricity production (2024) | % of global geothermal production (2024) |
|---|---|---|---|
| Australia | 0 | 0.0% | 0.0% |
| Austria | 0 | 0.0% | 0.0% |
| Canada | 6 | 0.0% | 0.0% |
| Chile | 95 | 0.4% | 0.6% |
| China | 26 | 0.0% | 0.2% |
| Taiwan | 7 | 0.0% | 0.0% |
| Costa Rica | 263 | 8.3% | 1.7% |
| Croatia | 10 | 0.0% | 0.0% |
| El Salvador | 209 | 11.2% | 1.4% |
| Ethiopia | 7 | 0.1% | 0.0% |
| France | 16 | 0.0% | 0.1% |
| Germany | 44 | 0.0% | 0.3% |
| Guadeloupe | 15 | 6.6% | 0.1% |
| Guatemala | 49 | 1.8% | 0.3% |
| Honduras | 39 | 2.0% | 0.3% |
| Hungary | 3 | 0.0% | 0.0% |
| Iceland | 788 | 26.8% | 5.1% |
| Indonesia | 2,688 | 18.8% | 17.4% |
| Italy | 772 | 1.1% | 5.0% |
| Japan | 461 | 0.3% | 3.0% |
| Kenya | 940 | 33.7% | 6.1% |
| Mexico | 999 | 2.9% | 6.5% |
| New Zealand | 1,275 | 14.3% | 8.3% |
| Nicaragua | 165 | 21.5% | 1.1% |
| Papua New Guinea | 51 | 12.8% | 0.3% |
| Philippines | 1,952 | 21.0% | 12.7% |
| Portugal | 29 | 0.1% | 0.2% |
| Romania | 0 | 0.0% | 0.0% |
| Russia | 81 | 0.1% | 0.5% |
| Thailand | 0 | 0.0% | 0.0% |
| Turkey | 1,734 | 2.5% | 11.2% |
| United States | 2,703 | 0.6% | 17.5% |
| Total | 16,738 |
Geothermal heating
Main article: Geothermal heating
Geothermal heating is the direct application of geothermal energy to heat buildings and water. Humans have been doing this since the Paleolithic era, making it one of our oldest energy technologies. In 2004, approximately seventy countries made direct use of a total of 270 PJ of geothermal heating. As of 2007, 28 GW of geothermal heating capacity was satisfying a mere 0.07% of global primary energy consumption. The thermal efficiency is remarkably high because no energy conversion is required, but the capacity factors tend to be low (around 20%) since the demand for heat is overwhelmingly seasonal.
Even ground that feels cold to the touch contains heat. Below a depth of 6 meters (20 ft), the undisturbed ground temperature remains consistently at the Mean Annual Air Temperature. This low-grade, ubiquitous heat can be extracted using a ground source heat pump.
Types
Hydrothermal systems
Hydrothermal systems are the low-hanging fruit of geothermal energy, accessing naturally occurring reservoirs of hot water or steam. These systems are categorized as either vapor-dominated or liquid-dominated.
Vapor-dominated plants
Larderello and The Geysers are prime examples of vapor-dominated sites. These are the jackpots of geothermal exploration, offering temperatures from 240 to 300 °C that produce superheated steam directly. This high-quality steam can be piped straight to a turbine, making for a relatively simple and efficient power plant.
Liquid-dominated plants
Liquid-dominated reservoirs (LDRs) are far more common. Those with temperatures exceeding 200 °C (392 °F) are typically found near young volcanoes, particularly around the Pacific Ocean, as well as in rift zones and over hot spots. Flash steam plants are the standard technology for exploiting these resources. Hot water is pumped from the well under high pressure; as the pressure drops, the water "flashes" into steam. Most wells of this type can generate 2–10 MW of electricity. The steam is separated from the remaining liquid using cyclone separators and then used to drive electric generators. The condensed liquid is returned down the well to be reheated and reused. As of 2013, the largest liquid-dominated system was Cerro Prieto in Mexico, generating 750 MW of electricity from temperatures as high as 350 °C (662 °F).
Lower-temperature LDRs, with temperatures between 120–200 °C, require pumping to bring the fluid to the surface. These are common in extensional terrains, where deep circulation along faults provides the heating mechanism, such as in the Western US and Turkey. For these cooler resources, water is passed through a heat exchanger in a Rankine cycle binary plant. The geothermal water heats a secondary organic working fluid with a lower boiling point, which vaporizes and drives a turbine. These binary plants, pioneered in the Soviet Union in the late 1960s, now dominate new plant construction. A significant advantage is that they are closed-loop systems with virtually no emissions.
Engineered geothermal systems
An engineered geothermal system is one that has been artificially created or improved by human intervention. These are deployed in reservoirs that have hot rocks but lack one of the other key ingredients for a natural hydrothermal system—namely, sufficient fluid, permeability, or porosity. Types include enhanced geothermal systems, closed-loop (or advanced) geothermal systems, and some superhot rock concepts.
Enhanced geothermal systems
Main article: Enhanced geothermal system
Enhanced geothermal systems (EGS) involve actively injecting water into wells to be heated by hot rock and then pumped back out. The water is injected under immense pressure to expand existing rock fissures, creating a permeable reservoir where none existed before. The technique was adapted from the fracking methods used in the oil and gas industry. However, the geologic formations are typically deeper, and crucially, no toxic chemicals are used, which reduces the potential for environmental damage. Instead, proppants like sand or ceramic particles are often used to keep the newly created cracks open and maintain optimal flow rates. Drillers can also employ directional drilling to significantly expand the size of the man-made reservoir.
Small-scale EGS projects have been installed in the Rhine Graben at Soultz-sous-Forêts in France and at Landau and Insheim in Germany.
Closed-loop geothermal systems
Main article: Closed-loop geothermal
Closed-loop geothermal systems, sometimes referred to as Advanced Geothermal Systems (AGS), are engineered systems where a working fluid is heated in the hot rock reservoir without ever coming into direct contact with the rock itself. The fluid remains contained within a closed loop of deeply buried pipes that act as a massive downhole heat exchanger. The advantages are clear: (1) no natural geofluid is required, (2) the hot rock doesn't need to be permeable or porous, and (3) all the working fluid is recirculated with zero loss. Eavor, a Canadian startup, piloted such a system in shallow, soft rock formations in Alberta, Canada. While the geothermal gradient in that sedimentary basin proved insufficient for power generation, the system did successfully produce approximately 11,000 MWh of thermal energy during its first two years of operation.
Economics
As is the case with wind and solar, the financial profile of geothermal power is dominated by capital costs, while operating costs are minimal. Drilling is the single largest expense, accounting for over half the total cost, and it's a high-risk venture. Not every well drilled will yield an exploitable resource. To illustrate, as of 2009, a typical well pair in Nevada (one for extraction, one for injection) capable of producing 4.5 megawatts (MW) cost about 50 million.
A power plant at The Geysers, a testament to the industrial scale required.
Drilling geothermal wells is inherently more expensive than drilling oil and gas wells of a similar depth for several reasons:
- Geothermal reservoirs are typically found in hard igneous or metamorphic rock, which is far more difficult to penetrate than the soft sedimentary rock of most hydrocarbon reservoirs.
- The rock is often heavily fractured, causing vibrations that can damage drill bits and other equipment.
- The rock can be highly abrasive, with a high quartz content, and may contain corrosive fluids.
- The extreme heat limits the use of sensitive downhole electronics.
- Well casings must be cemented from top to bottom to withstand the tendency to expand and contract with temperature fluctuations. In contrast, oil and gas wells are usually only cemented at the bottom.
- The well diameters required for geothermal are considerably larger than for typical oil and gas wells.
As of 2007, the cost for plant construction and well drilling was in the range of €2–5 million per MW of electrical capacity, while the break-even price for the electricity produced was between €0.04–0.10 per kW·h. Enhanced geothermal systems typically fall on the higher end of these ranges, with capital costs exceeding 0.054 per kW·h.
Between 2013 and 2020, private investment was the primary engine for renewable energy funding, making up about 75% of total financing. However, the mix of private and public funding differs significantly across technologies. In 2020, geothermal energy received only 32% of its investment from private sources, a sign of its perceived risk and high upfront costs.
Socioeconomic benefits
In January 2024, a report from the Energy Sector Management Assistance Program (ESMAP) titled "Socioeconomic Impacts of Geothermal Energy Development" highlighted that the socioeconomic benefits of geothermal development significantly exceed those of wind and solar. It is estimated to generate 34 jobs per megawatt across various sectors. The report emphasizes how geothermal projects foster skill development through both on-the-job training and formal education, strengthening the local workforce. It also points to the collaborative nature of development with local communities, leading to improved infrastructure, skill-building initiatives, and revenue-sharing models. These improvements can enhance access to reliable electricity and heat, which in turn can boost agricultural productivity and food security. The report also notes a commitment to advancing gender equality and social inclusion by providing opportunities to underrepresented groups. These efforts collectively drive domestic economic growth, increase fiscal revenues, and contribute to more stable national economies, all while delivering social benefits like improved health, education, and community cohesion.
Development
Geothermal projects unfold in several distinct stages, each with its own set of risks. Many potential projects are abandoned during the initial reconnaissance and geophysical survey phases, which are generally considered too speculative for traditional lending. Only the later stages, once a resource has been proven, can typically be equity-financed.
Precipitate scaling
A frequent operational headache in geothermal systems occurs when they are located in carbonate-rich formations. As the hot fluids are drawn toward the surface, they dissolve minerals from the rock. When these fluids cool, the dissolved cations precipitate out of the solution, forming a hard calcium scale—a phenomenon known as calcite scaling. This buildup can severely restrict flow rates and force system shutdowns for costly maintenance.
Sustainability
Geothermal energy is considered sustainable because the amount of heat we extract is minuscule compared to the Earth's total heat content, which is roughly 100 billion times the world's annual energy consumption in 2010. The planet's heat flows are not in equilibrium; Earth is, in fact, cooling on geologic timescales. Human heat extraction does not meaningfully accelerate this process. The practice of reinjecting the extracted water back into the borehole to be reheated further supports the argument for its renewability, though the returned water is at a lower temperature.
In many applications, replacing material use with energy has lessened the human environmental footprint. Geothermal offers the potential for further reductions. Iceland, for example, has enough geothermal energy to eliminate fossil fuels for electricity and to heat the sidewalks of Reykjavik, thereby eliminating the need for gritting with salt or sand.
Electricity generation at Poihipi, New Zealand Electricity generation at Ohaaki, New Zealand Electricity generation at Wairakei, New Zealand
However, the local effects of heat extraction cannot be ignored. Over decades, individual wells can draw down local temperatures and water levels until a new equilibrium is reached. The three oldest sites—at Larderello, Wairakei, and the Geysers—all experienced reduced output due to local depletion. Heat and water were extracted faster than they were naturally replenished. In some cases, reducing production and injecting additional water can allow these wells to recover some of their original capacity. Such management strategies have been implemented at some sites, and they continue to be significant energy producers.
The Wairakei power station, commissioned in November 1958, reached its peak generation of 173 MW in 1965. But by then, the supply of high-pressure steam was already faltering. In 1982, it was down-rated to use intermediate pressure, and its output fell to 157 MW. In 2005, two 8 MW isopentane binary cycle systems were added, boosting the output by about 14 MW.
Environmental effects
A geothermal power station in the Philippines, a landscape of pipes and steam. The Krafla Geothermal Station in northeast Iceland, set against a stark, volcanic backdrop.
The fluids drawn from deep underground are not pure water. They carry a mixture of dissolved gasses, notably carbon dioxide (CO₂), hydrogen sulfide (H₂S), methane (CH₄), and ammonia (NH₃). If released, these pollutants contribute to global warming, acid rain, and create noxious smells. Existing geothermal electric plants emit an average of 122 kilograms (269 lb) of CO₂ per megawatt-hour (MW·h) of electricity—a small fraction of the emission intensity of fossil fuel plants. However, some plants, such as certain facilities for geothermal power in Turkey, can emit more pollutants than gas-fired power plants, at least initially. Plants dealing with high levels of acids and volatile chemicals are typically equipped with emission-control systems. Emerging closed-loop technologies, like those being developed by Eavor, have the potential to eliminate these emissions entirely.
Geothermal water can also hold trace amounts of toxic elements in solution, such as mercury, arsenic, boron, and antimony. These chemicals precipitate out as the water cools and can cause significant environmental damage if released. The modern practice of reinjecting geothermal fluids back into the Earth to stimulate production has the welcome side benefit of mitigating this impact.
Construction can adversely affect land stability. Subsidence has occurred in the Wairakei field. In Staufen im Breisgau, Germany, the opposite occurred: tectonic uplift. A previously isolated layer of anhydrite came into contact with water and transformed into gypsum, doubling its volume and damaging buildings. Enhanced geothermal systems can trigger earthquakes as part of the hydraulic fracturing process. A project in Basel, Switzerland was suspended after more than 10,000 seismic events, measuring up to 3.4 on the Richter Scale, occurred during the first six days of water injection.
On the positive side, geothermal power has minimal land and freshwater requirements. Geothermal plants use about 3.5 square kilometers (1.4 sq mi) per gigawatt of electrical production, compared to 32 square kilometers (12 sq mi) for coal facilities and 12 square kilometers (4.6 sq mi) for wind farms. They consume 20 liters (5.3 US gal) of freshwater per MW·h, a trivial amount compared to the over 1,000 liters (260 US gal) per MW·h required for nuclear, coal, or oil plants.
Production
Philippines
The Philippines initiated geothermal research in 1962 when the Philippine Institute of Volcanology and Seismology began inspecting the geothermal region in Tiwi, Albay. The nation's first geothermal power plant was constructed in 1977 in Tongonan, Leyte. The New Zealand government was contracted to build the plant in 1972. The Tongonan Geothermal Field (TGF) later expanded to include the Upper Mahiao, Matlibog, and South Sambaloran plants, reaching a total capacity of 508 MW.
The first plant in the Tiwi region opened in 1979, with two more following in 1980 and 1982. The Tiwi geothermal field, located about 450 km from Manila, now has three plants producing 330 MWe, placing the Philippines among the world's top geothermal producers, behind the United States and Mexico. The country has 7 major geothermal fields and continues to pursue geothermal energy through its Philippine Energy Plan 2012–2030, which aims to produce 70% of the country's energy from renewable sources by 2030.
United States
According to the Geothermal Energy Association (GEA), installed geothermal capacity in the United States grew by 5%, or 147.05 MW, in 2013. This increase was driven by seven new geothermal projects that came online in 2012. The GEA also revised its 2011 estimate of installed capacity upward by 128 MW, bringing the total installed US geothermal capacity to 3,386 MW at the time.
Hungary
The municipal government of Szeged is undertaking an ambitious project to cut its natural gas consumption by 50 percent by using geothermal energy for its district heating system. The Szeged geothermal power station comprises 27 wells, 16 heating plants, and an extensive network of 250 kilometers of distribution pipes.