Editing Renewable energy (section)

== Mainstream technologies ==
<!--
This section is for a basic description of the main renewable energy technologies. New and emerging technologies should be added to the section towards the end of the article. Pros and cons of different technologies are discussed in [[Renewable energy debate]]. Thanks. -->
[[File:2011- Renewable energy capacity - International Energy Agency.svg |thumb|Renewable energy capacity has steadily grown, led by [[Photovoltaic system|solar photovoltaic]] power.<ref name=IEA_202306>Source for data beginning in 2017: {{cite web |title=Renewable Energy Market Update Outlook for 2023 and 2024 |url=https://iea.blob.core.windows.net/assets/63c14514-6833-4cd8-ac53-f9918c2e4cd9/RenewableEnergyMarketUpdate_June2023.pdf |website=IEA.org |publisher=International Energy Agency (IEA) |archive-url=https://web.archive.org/web/20230711115355/https://iea.blob.core.windows.net/assets/63c14514-6833-4cd8-ac53-f9918c2e4cd9/RenewableEnergyMarketUpdate_June2023.pdf |archive-date=11 July 2023 |page=19 |date=June 2023 |quote=IEA. CC BY 4.0. |url-status=live}} ● Source for data through 2016: {{cite web |title=Renewable Energy Market Update / Outlook for 2021 and 2022 |url=https://iea.blob.core.windows.net/assets/18a6041d-bf13-4667-a4c2-8fc008974008/RenewableEnergyMarketUpdate-Outlookfor2021and2022.pdf |website=IEA.org |publisher=International Energy Agency |archive-url=https://web.archive.org/web/20230325084025/https://iea.blob.core.windows.net/assets/18a6041d-bf13-4667-a4c2-8fc008974008/RenewableEnergyMarketUpdate-Outlookfor2021and2022.pdf |archive-date=25 March 2023 |page=8 |date=May 2021 |url-status=live |quote=IEA. Licence: CC BY 4.0 }}</ref>]]

=== Solar energy ===
{{main|Solar energy|Solar power|Outline of solar energy}}
{| class="wikitable"
! Installed capacity and other key design parameters
! Value and year
|-
| Global electricity power generation capacity || 1419.0 GW (2023){{sfn|IRENA|2024|p=21}}
|-
| Global electricity power generation capacity annual growth rate || 25% (2014-2023)<ref>{{harvnb|IRENA|2024|p=21}}. Note: Compound annual growth rate 2014-2023.</ref>
|-
| Share of global electricity generation || 5.5% (2023)<ref name="Ember 2024" />
|-
| Levelized cost per megawatt hour || Utility-scale photovoltaics: USD 38.343 (2019){{sfn|NREL ATB|2021|loc=Utility-Scale PV}}
|-
| Primary technologies || [[Photovoltaics]], [[concentrated solar power]], [[solar thermal collector]]
|-
| Main applications || Electricity, water heating, heating, ventilation, air conditioning ([[Heating, ventilation, and air conditioning|HVAC]])
|}
{{multiple image | total_width=450
| image1= SolarFachwerkhaus.jpg |caption1= A small, rooftop [[PV system]] in [[Bonn]], Germany
| image2= Mount Komekura Photovoltaic power plant Jan2012.JPG |caption2= [[Komekurayama Solar Power Plant|Komekurayama]] [[photovoltaic power station]] in [[Kofu]], Japan
}}
Solar power produced around 1.3 terrawatt-hours (TWh) worldwide in 2022,<ref name=":5" /> representing 4.6% of the world's electricity. Almost all of this growth has happened since 2010.<ref>{{Cite web |date=2023 |title=Data Page: Share of electricity generated by solar power |url=https://ourworldindata.org/grapher/share-electricity-solar?tab=table |website=[[Our World in Data]]}}</ref> Solar energy can be harnessed anywhere that receives sunlight; however, the amount of solar energy that can be harnessed for electricity generation is influenced by [[Weather|weather conditions]], geographic location and time of day.<ref>{{Cite web|date=2021-10-27 |url=https://www.c2es.org/content/renewable-energy/|access-date=2021-11-22|title=Renewable Energy|website=Center for Climate and Energy Solutions|url-status=live|archive-url=https://web.archive.org/web/20211118150404/https://www.c2es.org/content/renewable-energy/|archive-date=18 November 2021}}</ref>

There are two mainstream ways of harnessing solar energy: [[Solar thermal energy|solar thermal]], which converts solar energy into heat; and [[photovoltaics]] (PV), which converts it into electricity.<ref name=":2" /> PV is far more widespread, accounting for around two thirds of the global solar energy capacity as of 2022.<ref name=":4">{{Cite book |last1=Weiss |first1=Werner |url=https://www.iea-shc.org/Data/Sites/1/publications/Solar-Heat-Worldwide-2023.pdf |title=Solar heat worldwide |last2=Spörk-Dür |first2=Monika |publisher=International Energy Agency |year=2023 |pages=12 |language=en}}</ref> It is also growing at a much faster rate, with 170 GW newly installed capacity in 2021,<ref>{{Cite web |title=Solar - Fuels & Technologies |url=https://www.iea.org/fuels-and-technologies/solar |access-date=2022-06-27 |website=IEA |language=en-GB}}</ref> compared to 25 GW of solar thermal.<ref name=":4" />

[[Passive solar]] refers to a range of construction strategies and technologies that aim to optimize the distribution of solar heat in a building. Examples include [[solar chimney]]s,<ref name=":2" /> orienting a building to the sun, using [[Thermal mass|construction materials that can store heat]], and designing spaces that [[Ventilation (architecture)|naturally circulate air]].<ref>{{Cite journal |last1=Zaręba |first1=Anna |last2=Krzemińska |first2=Alicja |last3=Kozik |first3=Renata |last4=Adynkiewicz-Piragas |first4=Mariusz |last5=Kristiánová |first5=Katarina |date=2022-03-17 |title=Passive and Active Solar Systems in Eco-Architecture and Eco-Urban Planning |journal=Applied Sciences |language=en |volume=12 |issue=6 |pages=3095 |doi=10.3390/app12063095 |doi-access=free |issn=2076-3417}}</ref>

From 2020 to 2022, solar technology investments almost doubled from USD 162 billion to USD 308 billion, driven by the sector's increasing maturity and cost reductions, particularly in solar photovoltaic (PV), which accounted for 90% of total investments. China and the United States were the main recipients, collectively making up about half of all solar investments since 2013. Despite reductions in Japan and India due to policy changes and [[COVID-19]], growth in China, the United States, and a significant increase from Vietnam's feed-in tariff program offset these declines. Globally, the solar sector added 714 gigawatts (GW) of solar PV and [[concentrated solar power]] (CSP) capacity between 2013 and 2021, with a notable rise in large-scale solar heating installations in 2021, especially in China, Europe, Turkey, and Mexico.<ref name=":1" />

==== Photovoltaics ====
{{Main|Growth of photovoltaics|Solar power by country|List of photovoltaic power stations}}
[[File:1975 – Price of solar panels as a function of cumulative installed capacity.svg|thumb |[[Swanson's law]]–stating that solar module prices have dropped about 20% for each doubling of installed capacity—defines the "[[Experience curve effects|learning rate]]" of [[photovoltaics|solar photovoltaics]].<ref name=SolarPVlearningCurve>{{cite web |title=Solar (photovoltaic) panel prices vs. cumulative capacity |url=https://ourworldindata.org/grapher/solar-pv-prices-vs-cumulative-capacity |website=OurWorldInData.org |archive-url=https://archive.today/20250124235542/https://ourworldindata.org/grapher/solar-pv-prices-vs-cumulative-capacity |archive-date=24 January 2025 |date=2024 |url-status=live }} OWID credits source data to: Nemet (2009); Farmer & Lafond (2016); International Renewable Energy Agency (IRENA, 2024).</ref><ref>{{cite web |url=http://www.greentechmedia.com/articles/read/Is-there-really-a-Swansons-Law |title=Swanson's Law and Making US Solar Scale Like Germany |work=Greentech Media |date=2014-11-24}}</ref>]]
A [[photovoltaic system]], consisting of [[solar cell]]s assembled into [[Solar panel|panels]], converts light into electrical [[direct current]] via the [[photoelectric effect]].<ref>{{cite journal |last1=Dai |first1=Zhenbang |last2=Rappe |first2=Andrew M. |title=Recent progress in the theory of bulk photovoltaic effect |journal=Chemical Physics Reviews |date=1 March 2023 |volume=4 |issue=1 |doi=10.1063/5.0101513|arxiv=2206.00602 }}</ref><ref>{{cite web|title=Energy Sources: Solar|work=Department of Energy |url=https://www.energy.gov/energysources/solar.htm |access-date=19 April 2011|archive-date=14 April 2011 |archive-url=https://web.archive.org/web/20110414081047/http://www.energy.gov/energysources/solar.htm|url-status=live}}</ref> PV has several advantages that make it by far the fastest-growing renewable energy technology. It is cheap, low-maintenance and scalable; adding to an existing PV installation as demanded arises is simple. Its main disadvantage is its poor performance in cloudy weather.<ref name=":2" />

PV systems range from small, residential and commercial [[Rooftop solar power|rooftop]] or [[Building-integrated photovoltaics|building integrated]] installations,<ref>{{cite journal |last1=Petter Jelle |first1=Bjørn |last2=Breivik |first2=Christer |last3=Drolsum Røkenes |first3=Hilde |title=Building integrated photovoltaic products: A state-of-the-art review and future research opportunities |journal=Solar Energy Materials and Solar Cells |date=May 2012 |volume=100 |pages=69–96 |doi=10.1016/j.solmat.2011.12.016|bibcode=2012SEMSC.100...69P |hdl=11250/2436844 |hdl-access=free }}</ref><ref>{{cite journal |last1=Luthander |first1=Rasmus |last2=Widén |first2=Joakim |last3=Nilsson |first3=Daniel |last4=Palm |first4=Jenny |title=Photovoltaic self-consumption in buildings: A review |journal=Applied Energy |date=March 2015 |volume=142 |pages=80–94 |doi=10.1016/j.apenergy.2014.12.028|bibcode=2015ApEn..142...80L |url=http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113676 }}</ref><ref>{{cite journal |last1=Chung |first1=Hsien-Ching |title=The Long-Term Usage of an Off-Grid Photovoltaic System with a Lithium-Ion Battery-Based Energy Storage System on High Mountains: A Case Study in Paiyun Lodge on Mt. Jade in Taiwan |journal=Batteries |date=13 June 2024 |volume=10 |issue=6 |pages=202 |doi=10.3390/batteries10060202|doi-access=free |arxiv=2405.04225 }}</ref> to large utility-scale [[photovoltaic power station]].<ref>{{cite journal |last1=Fereidooni |first1=Mojtaba |last2=Mostafaeipour |first2=Ali |last3=Kalantar |first3=Vali |last4=Goudarzi |first4=Hossein |title=A comprehensive evaluation of hydrogen production from photovoltaic power station |journal=Renewable and Sustainable Energy Reviews |date=February 2018 |volume=82 |pages=415–423 |doi=10.1016/j.rser.2017.09.060|bibcode=2018RSERv..82..415F }}</ref><ref>{{cite journal |last1=Buerhop |first1=Claudia |last2=Bommes |first2=Lukas |last3=Schlipf |first3=Jan |last4=Pickel |first4=Tobias |last5=Fladung |first5=Andreas |last6=Peters |first6=Ian Marius |title=Infrared imaging of photovoltaic modules: a review of the state of the art and future challenges facing gigawatt photovoltaic power stations |journal=Progress in Energy |date=1 October 2022 |volume=4 |issue=4 |pages=042010 |doi=10.1088/2516-1083/ac890b|bibcode=2022PrEne...4d2010B }}</ref><ref>{{cite web |title=Solar Integrated in New Jersey |url=http://jcwinnie.biz/wordpress/?p=1724 |url-status=dead |archive-url=https://web.archive.org/web/20130719075405/http://jcwinnie.biz/wordpress/?p=1724 |archive-date=19 July 2013 |access-date=20 August 2013 |publisher=Jcwinnie.biz}}</ref> A household's solar panels can either be used for just that household or, if connected to an electrical grid, can be aggregated with millions of others.<ref>{{cite journal |last1=Sommerfeldt |first1=Nelson |last2=Madani |first2=Hatef |title=Revisiting the techno-economic analysis process for building-mounted, grid-connected solar photovoltaic systems: Part one – Review |journal=Renewable and Sustainable Energy Reviews |date=July 2017 |volume=74 |pages=1379–1393 |doi=10.1016/j.rser.2016.11.232|bibcode=2017RSERv..74.1379S }}</ref><ref>{{cite journal |last1=Sommerfeldt |first1=Nelson |last2=Madani |first2=Hatef |title=Revisiting the techno-economic analysis process for building-mounted, grid-connected solar photovoltaic systems: Part two - Application |journal=Renewable and Sustainable Energy Reviews |date=July 2017 |volume=74 |pages=1394–1404 |doi=10.1016/j.rser.2017.03.010|bibcode=2017RSERv..74.1394S }}</ref><ref>{{Cite news |title=Getting the most out of tomorrow's grid requires digitisation and demand response |url=https://www.economist.com/technology-quarterly/2022/06/23/getting-the-most-out-of-tomorrows-grid-requires-digitisation-and-demand-response |access-date=2022-06-24 |newspaper=[[The Economist]] |issn=0013-0613}}</ref>

The first utility-scale solar power plant was built in 1982 in [[Hesperia, California]] by [[ARCO]].<ref>{{cite journal |url=https://www.osti.gov/biblio/5049780 |title=Design, installation and performance of ARCO solar photovoltaic power plants |journal=Conf. Rec. IEEE Photovoltaic Spec. Conf.; (United States)|date=May 1984 |osti=5049780 |last1=Tolbert |first1=R. E. L. |last2=Arnett |first2=J. C. }}</ref><ref>{{Cite web |title=The History of Solar |url=https://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf |access-date=April 7, 2024 |website=U.S. Department of Energy}}</ref> The plant was not profitable and was sold eight years later.<ref>{{Cite web |last=Lee |first=Patrick |date=1990-01-12 |title=Arco Sells Last 3 Solar Plants for $2 Million : Energy: The sale to New Mexico investors demonstrates the firm's strategy of focusing on its core oil and gas business. |url=https://www.latimes.com/archives/la-xpm-1990-01-12-fi-323-story.html |access-date=2024-04-07 |website=Los Angeles Times |language=en-US}}</ref> However, over the following decades, PV cells became significantly more efficient and cheaper.<ref name="deutsche-2015-chasm">{{cite web |date=27 February 2015 |title=Crossing the Chasm |url=https://www.db.com/cr/en/docs/solar_report_full_length.pdf |url-status=live |archive-url=https://web.archive.org/web/20150330174336/https://www.db.com/cr/en/docs/solar_report_full_length.pdf |archive-date=30 March 2015 |publisher=Deutsche Bank Markets Research}}</ref> As a result, PV adoption has grown exponentially since 2010.<ref>{{Cite journal |last1=Ravishankar |first1=Rashmi |last2=AlMahmoud |first2=Elaf |last3=Habib |first3=Abdulelah |last4=de Weck |first4=Olivier L. |date=January 2022 |title=Capacity Estimation of Solar Farms Using Deep Learning on High-Resolution Satellite Imagery |journal=Remote Sensing |language=en |volume=15 |issue=1 |pages=210 |doi=10.3390/rs15010210 |doi-access=free |bibcode=2022RemS...15..210R |issn=2072-4292|hdl=1721.1/146994 |hdl-access=free }}</ref> Global capacity increased from 230 GW at the end of 2015 to 890 GW in 2021.<ref name="IRENA2018">{{cite web |title=Renewable Electricity Capacity And Generation Statistics June 2018 |url=http://resourceirena.irena.org/gateway/dashboard/?topic=4&subTopic=54 |url-status=dead |archive-url=https://web.archive.org/web/20181128034842/http://resourceirena.irena.org/gateway/dashboard/?topic=4&subTopic=54 |archive-date=28 November 2018 |access-date=27 November 2018}}</ref> PV grew fastest in China between 2016 and 2021, adding 560 GW, more than all advanced economies combined.<ref name="IEA-3" /> Four of the ten biggest solar power stations are in China, including the biggest, [[Huanghe Hydropower Golmud Solar Park|Golmud Solar Park]] in China.<ref>{{Cite web |last=Ahmad |first=Mariam |date=2023-05-30 |title=Top 10: Largest Solar Power Parks |url=https://energydigital.com/top10/top-10-largest-solar-power-parks |access-date=2024-04-07 |website=energydigital.com |language=en}}</ref>

[[Solar cell#Recycling|Solar panels are recycled]] to reduce [[electronic waste]] and create a source for materials that would otherwise need to be mined,<ref>{{Cite web |last= |first= |date=2021-08-23 |title=Solar Panel Recycling |url=https://www.epa.gov/hw/solar-panel-recycling |access-date=2022-05-02 |website=www.epa.gov |language=en}}</ref> but such business is still small and work is ongoing to improve and scale-up the process.<ref name="techrev">{{cite web |title=Solar panels are a pain to recycle. These companies are trying to fix that. |url=https://www.technologyreview.com/2021/08/19/1032215/solar-panels-recycling/ |url-status=live |archive-url=https://web.archive.org/web/20211108103705/https://www.technologyreview.com/2021/08/19/1032215/solar-panels-recycling/ |archive-date=8 November 2021 |access-date=8 November 2021 |website=MIT Technology Review}}</ref><ref>{{cite journal |last1=Heath |first1=Garvin A. |last2=Silverman |first2=Timothy J. |last3=Kempe |first3=Michael |last4=Deceglie |first4=Michael |last5=Ravikumar |first5=Dwarakanath |last6=Remo |first6=Timothy |last7=Cui |first7=Hao |last8=Sinha |first8=Parikhit |last9=Libby |first9=Cara |last10=Shaw |first10=Stephanie |last11=Komoto |first11=Keiichi |last12=Wambach |first12=Karsten |last13=Butler |first13=Evelyn |last14=Barnes |first14=Teresa |last15=Wade |first15=Andreas |date=July 2020 |title=Research and development priorities for silicon photovoltaic module recycling to support a circular economy |url=https://www.nature.com/articles/s41560-020-0645-2 |url-status=live |journal=Nature Energy |volume=5 |issue=7 |pages=502–510 |bibcode=2020NatEn...5..502H |doi=10.1038/s41560-020-0645-2 |issn=2058-7546 |s2cid=220505135 |archive-url=https://web.archive.org/web/20210821071335/https://www.nature.com/articles/s41560-020-0645-2 |archive-date=21 August 2021 |access-date=26 June 2021}}</ref><ref>{{cite journal |last1=Domínguez |first1=Adriana |last2=Geyer |first2=Roland |date=1 April 2019 |title=Photovoltaic waste assessment of major photovoltaic installations in the United States of America |journal=Renewable Energy |volume=133 |pages=1188–1200 |bibcode=2019REne..133.1188D |doi=10.1016/j.renene.2018.08.063 |issn=0960-1481 |s2cid=117685414}}</ref>

==== Solar thermal ====
{{Main|Solar thermal energy}}
Unlike photovoltaic cells that convert sunlight directly into electricity, solar thermal systems convert it into heat. They use mirrors or lenses to concentrate sunlight onto a receiver, which in turn heats a water reservoir. The heated water can then be used in homes. The advantage of solar thermal is that the heated water can be stored until it is needed, eliminating the need for a separate energy storage system.<ref>{{Cite news |last=Coren |first=Michael |date=February 13, 2024 |title=Meet the other solar panel |url=https://www.washingtonpost.com/climate-environment/2024/02/13/solar-thermal-water-heater/ |newspaper=[[The Washington Post]]}}</ref> Solar thermal power can also be converted to electricity by using the steam generated from the heated water to drive a [[turbine]] connected to a generator. However, because generating electricity this way is much more expensive than photovoltaic power plants, there are very few in use today.<ref>{{Cite news |last1=Kingsley |first1=Patrick |last2=Elkayam |first2=Amit |date=October 9, 2022 |title='Eye of Sauron': The Dazzling Solar Tower in the Israeli Desert |url=https://www.nytimes.com/2022/10/09/world/middleeast/israel-solar-tower.html |work=The New York Times}}</ref>

==== Floatovoltaics ====
{{Main article|Https://en.wikipedia.org/wiki/Floating solar}}
Floatovoltiacs, or floating solar panels, are solar panels floating on bodies of water. There are both positive and negative points to this. Some positive points are increased efficiency and price decrease of water space compared to land space. A negative point is that making floating solar panels could be more expensive.

==== Agrivoltiacs ====
{{Main|https://en.wikipedia.org/wiki/Agrivoltaics}}
Agrivoltiacs is where there is simultaneous use of land for energy production and agriculture. There are again both positive and negative points. A positive viewpoint is there is a better use of land, which leads to lower land costs. A negative viewpoint is it the plants grown underneath would have to be plants that can grow well under shade, such as [[Polka Dot Plant]], [[Pineapple Sage]], and [[Begonia]].<ref>{{Cite web |title=19 Top Shade Plants - Shade-Loving Plants for Your Garden |url=https://www.provenwinners.com/learn/top-ten-lists/10-plants-for-your-shade-garden |access-date=2025-02-13 |website=Proven Winners}}</ref> Agrivoltaics not only optimizes land use and reduces costs by enabling dual revenue streams from both energy production and agriculture, but it can also help moderate temperatures beneath the panels, potentially reducing water loss and improving microclimates for crop growth. However, careful design and crop selection are crucial, as the shading effect may limit the types of plants that can thrive, necessitating the use of shade-tolerant species and innovative management practices. <ref>{{Cite web |title=Agrivoltaics: Producing Solar Energy While Protecting Farmland |url=https://cbey.yale.edu/research/agrivoltaics-producing-solar-energy-while-protecting-farmland |access-date=2025-03-30 |website=Yale Center for Business and the Environment |language=en}}</ref>

=== Wind power ===
{{Main|Wind power|Wind power by country}}
[[File:Wind energy generation by region, OWID.svg|thumb|300px|Wind energy generation by region over time<ref>{{cite web |title=Wind energy generation by region |url=https://ourworldindata.org/grapher/wind-energy-consumption-by-region |website=Our World in Data |access-date=15 August 2023 |archive-date=10 March 2020 |archive-url=https://web.archive.org/web/20200310222609/https://ourworldindata.org/grapher/wind-energy-consumption-by-region |url-status=live}}</ref>]]
[[File:Pretty flamingos - geograph.org.uk - 578705.jpg|thumb|[[Burbo Bank Offshore Wind Farm|Burbo]], [[North West England|NW-England]]]]
[[File:Fentonwindpark1.jpg|thumb|Sunrise at the [[Fenton Wind Farm]] in Minnesota, United States]]
{| class="wikitable"
! Installed capacity and other key design parameters
! Value and year
|-
| Global electricity power generation capacity || 1017.2 GW (2023){{sfn|IRENA|2024|p=14}}
|-
| Global electricity power generation capacity annual growth rate || 13% (2014-2023)<ref>{{harvnb|IRENA|2024|p=14}}. Note: Compound annual growth rate 2014-2023.</ref>
|-
| Share of global electricity generation || 7.8% (2023)<ref name="Ember 2024" />
|-
| Levelized cost per megawatt hour || Land-based wind: USD 30.165 (2019){{sfn|NREL ATB|2021|loc=Land-Based Wind}}
|-
| Primary technology || [[Wind turbine]], [[windmill]]
|-
| Main applications || Electricity, pumping water ([[windpump]])
|}Humans have harnessed wind energy since at least 3500 BC. Until the 20th century, it was primarily used to power ships, windmills and water pumps. Today, the vast majority of wind power is used to generate electricity using wind turbines.<ref name=":2" /> Modern utility-scale wind turbines range from around 600&nbsp;kW to 9 MW of rated power. The power available from the wind is a function of the cube of the wind speed, so as wind speed increases, power output increases up to the maximum output for the particular turbine.<ref name="EWEA">{{cite web | title = Analysis of Wind Energy in the EU-25 | publisher = European Wind Energy Association | url = http://www.ewea.org/fileadmin/ewea_documents/documents/publications/WETF/Facts_Summary.pdf | access-date = 11 March 2007 | archive-date = 12 March 2007 | archive-url = https://web.archive.org/web/20070312221118/http://www.ewea.org/fileadmin/ewea_documents/documents/publications/WETF/Facts_Summary.pdf | url-status = live }}</ref> Areas where winds are stronger and more constant, such as [[Offshore wind power|offshore]] and high-altitude sites, are preferred locations for wind farms.

Wind-generated electricity met nearly 4% of global electricity demand in 2015, with nearly 63&nbsp;GW of new wind power capacity installed. Wind energy was the leading source of new capacity in Europe, the US and Canada, and the second largest in China. In Denmark, wind energy met more than 40% of its electricity demand while Ireland, Portugal and [[Renewable energy in Spain|Spain]] each met nearly 20%.<ref>{{Cite web|title=Electricity – from other renewable sources - The World Factbook|url=https://www.cia.gov/the-world-factbook/field/electricity-from-other-renewable-sources|access-date=2021-10-27|website=www.cia.gov|archive-date=27 October 2021|archive-url=https://web.archive.org/web/20211027205510/https://www.cia.gov/the-world-factbook/field/electricity-from-other-renewable-sources|url-status=live}}</ref>

Globally, the long-term technical potential of wind energy is believed to be five times total current global energy production, or 40 times current electricity demand, assuming all practical barriers needed were overcome. This would require wind turbines to be installed over large areas, particularly in areas of higher wind resources, such as offshore, and likely also industrial use of new types of VAWT turbines in addition to the horizontal axis units currently in use. As offshore wind speeds average ~90% greater than that of land, offshore resources can contribute substantially more energy than land-stationed turbines.<ref>"Offshore stations experience mean wind speeds at 80 m that are 90% greater than over land on average." [http://www.stanford.edu/group/efmh/winds/global_winds.html Evaluation of global wind power] {{Webarchive|url=https://web.archive.org/web/20080525114202/http://www.stanford.edu/group/efmh/winds/global_winds.html |date=25 May 2008 }} "Overall, the researchers calculated winds at 80 meters [300 feet] above [[sea level]] traveled over the ocean at approximately 8.6 meters per second and at nearly 4.5 meters per second over land [20 and 10 miles per hour, respectively]." [http://www.ens-newswire.com/ens/may2005/2005-05-17-09.asp#anchor6 Global Wind Map Shows Best Wind Farm Locations] {{Webarchive|url=https://web.archive.org/web/20050524075533/http://ens-newswire.com/ens/may2005/2005-05-17-09.asp#anchor6 |date=24 May 2005 }}. Retrieved 30 January 2006.</ref>

Investments in wind technologies reached USD 161 billion in 2020, with onshore wind dominating at 80% of total investments from 2013 to 2022. Offshore wind investments nearly doubled to USD 41 billion between 2019 and 2020, primarily due to policy incentives in China and expansion in Europe. Global wind capacity increased by 557 GW between 2013 and 2021, with capacity additions increasing by an average of 19% each year.<ref name=":1" />

=== Hydropower ===
{{Main|Hydroelectricity|Hydropower|}}

[[File:ThreeGorgesDam-China2009.jpg|thumb|The [[Three Gorges Dam]] for [[hydropower]] on the [[Yangtze River]] in China]]
[[File:Three gorges dam from space.jpg|thumb|[[Three Gorges Dam]] and [[Gezhouba Dam]], China]]
{| class="wikitable"
! Installed capacity and other key design parameters
! Value and year
|-
| Global electricity power generation capacity || 1,267.9 GW (2023)<ref>{{harvnb|IRENA|2024|p=9}}. Note: Excludes pure pumped storage.</ref>
|-
| Global electricity power generation capacity annual growth rate || 1.9% (2014-2023)<ref>{{harvnb|IRENA|2024|p=9}}. Note: Excludes pure pumped storage. Compound annual growth rate 2014-2023.</ref>
|-
| Share of global electricity generation || 14.3% (2023)<ref name="Ember 2024">{{cite web |date=8 May 2024 |title=Global Electricity Review 2024 |url=https://ember-energy.org/latest-insights/global-electricity-review-2024/ |access-date=8 May 2024 |publisher=[[Ember (non-profit organisation)|Ember]]}}</ref>
|-
| Levelized cost per megawatt hour || USD 65.581 (2019){{sfn|NREL ATB|2021|loc=Hydropower}}
|-
| Primary technology || [[Hydroelectricity#Generating methods|Dam]]
|-
| Main applications || Electricity, [[Pumped-storage hydroelectricity|pumped storage]], [[Hydropower#Mechanical power|mechanical power]]
|}

Since water is about 800 times [[Density of air|denser than air]], even a slow flowing stream of water, or moderate sea [[Swell (ocean)|swell]], can yield considerable amounts of energy. Water can generate electricity with a [[Energy conversion efficiency|conversion efficiency]] of about 90%, which is the highest rate in renewable energy.<ref name="Ang">{{cite journal |last1=Ang |first1=Tze-Zhang |last2=Salem |first2=Mohamed |last3=Kamarol |first3=Mohamad |last4=Das |first4=Himadry Shekhar |last5=Nazari |first5=Mohammad Alhuyi |last6=Prabaharan |first6=Natarajan |title=A comprehensive study of renewable energy sources: Classifications, challenges and suggestions |journal=Energy Strategy Reviews |date=2022 |volume=43 |pages=100939 |doi=10.1016/j.esr.2022.100939 |s2cid=251889236 |language=en |issn=2211-467X |doi-access=free|bibcode=2022EneSR..4300939A }}</ref> There are many forms of water energy:
* Historically, hydroelectric power came from constructing large hydroelectric dams and reservoirs, which are still popular in [[Developing country|developing countries]].<ref>{{Cite journal|last1=Moran |first1=Emilio F. |last2=Lopez|first2=Maria Claudia|last3=Moore|first3=Nathan|last4=Müller|first4=Norbert |last5=Hyndman|first5=David W.|date=2018|title=Sustainable hydropower in the 21st century |journal=Proceedings of the National Academy of Sciences|volume=115|issue=47|pages=11891–11898 |doi=10.1073/pnas.1809426115|pmid=30397145|issn=0027-8424|pmc=6255148|bibcode=2018PNAS..11511891M |doi-access=free}}</ref> The [[List of largest hydroelectric power stations|largest]] of them are the [[Three Gorges Dam]] (2003) in [[China]] and the [[Itaipu Dam]] (1984) built by Brazil and Paraguay.
* [[Small hydro]] systems are hydroelectric power installations that typically produce up to {{nowrap|50 MW}} of power. They are often used on small rivers or as a low-impact development on larger rivers. China is the largest producer of hydroelectricity in the world and has more than 45,000 small hydro installations.<ref>{{cite web |url=https://www.irena.org/DocumentDownloads/Publications/RE_Technologies_Cost_Analysis-HYDROPOWER.pdf |title=DocHdl2OnPN-PRINTRDY-01tmpTarget |access-date=26 March 2019 |archive-date=9 November 2018 |archive-url=https://web.archive.org/web/20181109085415/https://www.irena.org/documentdownloads/publications/re_technologies_cost_analysis-hydropower.pdf |url-status=dead }}</ref>
* [[Run-of-the-river hydroelectricity]] plants derive energy from rivers without the creation of a large [[reservoir]]. The water is typically conveyed along the side of the river valley (using channels, pipes or tunnels) until it is high above the valley floor, whereupon it can be allowed to fall through a penstock to drive a turbine. A run-of-river plant may still produce a large amount of electricity, such as the [[Chief Joseph Dam]] on the Columbia River in the United States.<ref>{{cite web|title=Run-of-the-river hydroelectricity|url=https://energyeducation.ca/encyclopedia/Run-of-the-river_hydroelectricity |last=Afework|first=Bethel|date=3 September 2018|work=Energy Education|access-date=27 April 2019|archive-url=https://web.archive.org/web/20190427184803/https://energyeducation.ca/encyclopedia/Run-of-the-river_hydroelectricity|archive-date=27 April 2019|url-status=live}}</ref> However many run-of-the-river hydro power plants are [[micro hydro]] or [[pico hydro]] plants.

Much hydropower is flexible, thus complementing wind and solar, as it not intermittent.<ref>{{Cite web |title=Net zero: International Hydropower Association |url=https://www.hydropower.org/net-zero |access-date=2022-06-24 |website=www.hydropower.org |language=en}}</ref> In 2021, the world renewable hydropower capacity was 1,360 GW.<ref name="IEA-3" /> Only a third of the world's estimated hydroelectric potential of 14,000 TWh/year has been developed.<ref name="iha2021">{{cite web |date=11 June 2021 |title=Hydropower Status Report |url=https://www.hydropower.org/status-report |url-status=dead |archive-url=https://web.archive.org/web/20230403212029/https://www.hydropower.org/status-report |archive-date=3 April 2023 |access-date=30 May 2022 |website=International Hydropower Association}}</ref><ref name="etp2006">{{cite book |url=https://www.iea.org/reports/energy-technology-perspectives-2006 |title=Energy Technology Perspectives: Scenarios and Strategies to 2050 |date=2006 |publisher=International Energy Agency |isbn=926410982X |location=Paris |pages=124 |access-date=30 May 2022}}</ref> New hydropower projects face opposition from local communities due to their large impact, including relocation of communities and flooding of wildlife habitats and farming land.<ref>{{Cite web |title=Environmental Impacts of Hydroelectric Power {{!}} Union of Concerned Scientists |url=https://www.ucsusa.org/resources/environmental-impacts-hydroelectric-power |url-status=live |archive-url=https://web.archive.org/web/20210715234227/https://www.ucsusa.org/resources/environmental-impacts-hydroelectric-power |archive-date=15 July 2021 |access-date=9 July 2021 |website=www.ucsusa.org}}</ref> High cost and lead times from permission process, including environmental and risk assessments, with lack of environmental and social acceptance are therefore the primary challenges for new developments.<ref>{{Cite web |title=Hydropower Special Market Report |url=https://iea.blob.core.windows.net/assets/4d2d4365-08c6-4171-9ea2-8549fabd1c8d/HydropowerSpecialMarketReport_corr.pdf |url-status=live |archive-url=https://web.archive.org/web/20210707021807/https://iea.blob.core.windows.net/assets/4d2d4365-08c6-4171-9ea2-8549fabd1c8d/HydropowerSpecialMarketReport_corr.pdf |archive-date=7 July 2021 |access-date=9 July 2021 |website=IEA |pages=34–36}}</ref> It is popular to repower old dams thereby increasing their efficiency and capacity as well as quicker responsiveness on the grid.<ref>{{cite web |author1=L. Lia |author2=T. Jensen |author3=K.E. Stensbyand |author4=G. Holm |author5=A.M. Ruud |title=The current status of hydropower development and dam construction in Norway |url=https://www.ntnu.no/documents/381182060/641036380/Leif+Lia_FINAL.PDF/32bac8f3-b443-493b-a1eb-e22ce572acd9 |url-status=live |archive-url=https://web.archive.org/web/20170525165854/https://www.ntnu.no/documents/381182060/641036380/Leif+Lia_FINAL.PDF/32bac8f3-b443-493b-a1eb-e22ce572acd9 |archive-date=25 May 2017 |access-date=26 March 2019 |website=Ntnu.no |format=PDF}}</ref> Where circumstances permit existing dams such as the [[Richard B. Russell Dam|Russell Dam]] built in 1985 may be updated with "pump back" facilities for [[pumped-storage hydroelectricity|pumped-storage]] which is useful for peak loads or to support intermittent wind and solar power. Because [[Dispatchable generation|dispatchable power]] is more valuable than VRE<ref>{{Cite web |date=2021-04-19 |title=How Norway became Europe's biggest power exporter |url=https://www.power-technology.com/analysis/how-norway-became-europes-biggest-power-exporter/ |url-status=dead |archive-url=https://web.archive.org/web/20220627153206/https://www.power-technology.com/analysis/how-norway-became-europes-biggest-power-exporter/ |archive-date=27 June 2022 |access-date=2022-06-27 |website=Power Technology |language=en-US}}</ref><ref>{{Cite web |date=17 January 2022 |title=Trade surplus soars on energy exports {{!}} Norway's News in English — www.newsinenglish.no |url=https://www.newsinenglish.no/2022/01/17/trade-surplus-soars-on-energy-exports/ |access-date=2022-06-27 |language=en-US}}</ref> countries with large hydroelectric developments such as Canada and Norway are spending billions to expand their grids to trade with neighboring countries having limited hydro.<ref>{{cite web |title=New Transmission Line Reaches Milestone |url=http://www.vpr.net/news_detail/88975/new-transmission-line-reaches-milestone/ |url-status=live |archive-url=https://web.archive.org/web/20170203164110/http://www.vpr.net/news_detail/88975/new-transmission-line-reaches-milestone/ |archive-date=3 February 2017 |access-date=3 February 2017 |website=Vpr.net}}</ref>

=== Bioenergy ===
{{Main|Bioenergy}}
{{Further|Biomass (energy)#Environmental impacts}}
{| class="wikitable"
! Installed capacity and other key design parameters
! Value and year
|-
| Global electricity generation capacity || 150.3 GW (2023){{sfn|IRENA|2024|p=30}}
|-
| Global electricity generation capacity annual growth rate || 5.8% (2014-2023)<ref>{{harvnb|IRENA|2024|p=30}}. Note: Compound annual growth rate 2014-2023.</ref>
|-
| Share of global electricity generation || 2.4% (2022)<ref name="Ember 2024" />
|-
| Levelized cost per megawatt hour || USD 118.908 (2019){{sfn|NREL ATB|2021|loc=Other Technologies (EIA)}}
|-
| Primary technologies || [[Biomass (energy)|Biomass]], [[biofuel]]
|-
| Main applications || Electricity, heating, cooking, transportation fuels
|}

[[Biomass (energy)|Biomass]] is biological material derived from living, or recently living organisms. Most commonly, it refers to plants or plant-derived materials. As an energy source, biomass can either be used directly via [[combustion]] to produce heat, or converted to a more energy-dense [[biofuel]] like ethanol. Wood is the most significant biomass energy source as of 2012<ref name="Scheck2012">{{cite news |last1=Scheck |first1=Justin |last2=Dugan |first2=Ianthe Jeanne |title=Wood-Fired Plants Generate Violations |date=23 July 2012 |work=[[The Wall Street Journal]] |url=https://www.wsj.com/articles/SB10001424052702303740704577524822063133842 |access-date=18 July 2021 |url-status=live |archive-date=25 July 2021 |archive-url=https://web.archive.org/web/20210725004649/https://www.wsj.com/articles/SB10001424052702303740704577524822063133842}}</ref> and is usually sourced from a trees cleared for [[Silviculture|silvicultural]] reasons or [[fire prevention]]. Municipal wood waste – for instance, construction materials or sawdust – is also often burned for energy.<ref>{{Cite web |title=FAQs • What is woody biomass, and where does it come from? |url=https://www.placer.ca.gov/Faq.aspx?QID=1059 |access-date=2024-05-05 |website=[[Placer County|Placer County Government]]}}</ref> The biggest per-capita producers of wood-based bioenergy are heavily forested countries like Finland, Sweden, Estonia, Austria, and Denmark.<ref>{{Cite book |last=Pelkmans |first=Luc |url=https://www.ieabioenergy.com/wp-content/uploads/2021/11/CountriesReport2021_final.pdf |title=IEA Bioenergy Countries' Report: Implementation of bioenergy in the IEA Bioenergy member countries |date=November 2021 |publisher=International Energy Agency |isbn=978-1-910154-93-9 |pages=10 |language=en}}</ref>

Bioenergy can be environmentally destructive if old-growth forests are cleared to make way for crop production. In particular, demand for palm oil to produce biodiesel has contributed to the deforestation of tropical rainforests in Brazil and Indonesia.<ref name=":10" /> In addition, burning biomass still produces carbon emissions, although much less than fossil fuels (39 grams of CO<sub>2</sub> per megajoule of energy, compared to 75 g/MJ for fossil fuels).<ref>{{Cite magazine |last=UK |first=Maria Mellor, WIRED |title=Biofuels are meant to clean up flying's carbon crisis. They won't |url=https://www.wired.com/story/biofuels-aviation-carbon-emissions/ |access-date=2024-05-05 |magazine=Wired |language=en-US |issn=1059-1028}}</ref>

Some [[biomass (energy)|biomass]] sources are unsustainable at current rates of exploitation (as of 2017).<ref name="CarbonBrief1">{{cite web |last=Timperly |first=Jocelyn |date=23 February 2017 |title=Biomass subsidies 'not fit for purpose', says Chatham House |url=https://www.carbonbrief.org/biomass-subsidies-not-fit-for-purpose-chatham-house |url-status=live |archive-url=https://web.archive.org/web/20201106210822/https://www.carbonbrief.org/biomass-subsidies-not-fit-for-purpose-chatham-house |archive-date=6 November 2020 |access-date=31 October 2020 |publisher=Carbon Brief Ltd © 2020 - Company No. 07222041}}</ref>[[File:Metz biomass power station.jpg|thumb|A [[Cogeneration|CHP power station]] using wood to supply 30,000 households in France]]

==== Biofuel ====
{{Main|Biofuel}}
{{See also|Ethanol fuel|Sustainable biofuel|Issues relating to biofuels}}
[[Biofuel]]s are primarily used in transportation, providing 3.5% of the world's transport energy demand in 2022,<ref>{{Cite web |title=Biofuels |url=https://www.iea.org/energy-system/low-emission-fuels/biofuels |access-date=2024-05-05 |website=International Energy Agency |language=en}}</ref> up from 2.7% in 2010.{{sfn|REN21 Renewables Global Status Report|2011|pp=13-14}} [[Biojet]] is expected to be important for short-term reduction of carbon dioxide emissions from long-haul flights.<ref>{{Cite web |title=Japan to create bio jet fuel supply chain in clean energy push |url=https://asia.nikkei.com/Business/Transportation/Japan-to-create-bio-jet-fuel-supply-chain-in-clean-energy-push |access-date=2022-04-26 |website=Nikkei Asia |language=en-GB}}</ref>

Aside from wood, the major sources of bioenergy are [[Ethanol fuel|bioethanol]] and [[biodiesel]].<ref name=":2" /> Bioethanol is usually produced by fermenting the sugar components of crops like [[sugarcane]] and [[maize]], while biodiesel is mostly made from oils extracted from plants, such as [[soybean oil]] and [[corn oil]].<ref name=":9">{{Cite web |last=Martin |first=Jeremy |date=2016-06-22 |title=Everything You Ever Wanted to Know About Biodiesel (Charts and Graphs Included!) |url=https://blog.ucsusa.org/jeremy-martin/all-about-biodiesel/ |access-date=2024-05-05 |website=The Equation |language=en-US}}</ref> Most of the crops used to produce bioethanol and biodiesel are grown specifically for this purpose,<ref>{{cite web|title=Energy crops|url=http://www.biomassenergycentre.org.uk/portal/page?_pageid=75,17301&_dad=portal&_schema=PORTAL|work=crops are grown specifically for use as fuel|publisher=BIOMASS Energy Centre|access-date=6 April 2013|archive-url=https://web.archive.org/web/20130310063405/http://www.biomassenergycentre.org.uk/portal/page?_pageid=75,17301&_dad=portal&_schema=PORTAL|archive-date=10 March 2013|url-status=dead}}</ref> although used [[cooking oil]] accounted for 14% of the oil used to produce biodiesel as of 2015.<ref name=":9" /> The biomass used to produce biofuels varies by region. Maize is the major feedstock in the United States, while sugarcane dominates in Brazil.<ref>{{Cite journal |last1=Liu |first1=Xinyu |last2=Kwon |first2=Hoyoung |last3=Wang |first3=Michael |last4=O’Connor |first4=Don |date=2023-08-15 |title=Life Cycle Greenhouse Gas Emissions of Brazilian Sugar Cane Ethanol Evaluated with the GREET Model Using Data Submitted to RenovaBio |journal=Environmental Science & Technology |language=en |volume=57 |issue=32 |pages=11814–11822 |doi=10.1021/acs.est.2c08488 |pmid=37527415 |bibcode=2023EnST...5711814L |issn=0013-936X|pmc=10433513 }}</ref> In the European Union, where biodiesel is more common than bioethanol, [[rapeseed oil]] and [[palm oil]] are the main feedstocks.<ref>{{Cite web |date=2022 |title=Biofuels |url=https://www.oecd-ilibrary.org/sites/cdc97c88-en/index.html?itemId=/content/component/cdc97c88-en |access-date=2024-05-05 |website=OECD Library |language=en}}</ref> China, although it produces comparatively much less biofuel, uses mostly corn and wheat.<ref>{{Cite journal |last1=Qin |first1=Zhangcai |last2=Zhuang |first2=Qianlai |last3=Cai |first3=Ximing |last4=He |first4=Yujie |last5=Huang |first5=Yao |last6=Jiang |first6=Dong |last7=Lin |first7=Erda |last8=Liu |first8=Yaling |last9=Tang |first9=Ya |last10=Wang |first10=Michael Q. |date=February 2018 |title=Biomass and biofuels in China: Toward bioenergy resource potentials and their impacts on the environment |url=https://linkinghub.elsevier.com/retrieve/pii/S1364032117312170 |journal=Renewable and Sustainable Energy Reviews |language=en |volume=82 |pages=2387–2400 |doi=10.1016/j.rser.2017.08.073|bibcode=2018RSERv..82.2387Q }}</ref> In many countries, biofuels are either subsidized or mandated to be [[Common ethanol fuel mixtures|included in fuel mixtures]].<ref name=":10">{{Cite web |last=Loyola |first=Mario |date=2019-11-23 |title=Stop the Ethanol Madness |url=https://www.theatlantic.com/ideas/archive/2019/11/ethanol-has-forsaken-us/602191/ |access-date=2024-05-05 |website=The Atlantic |language=en}}</ref>
[[File:Faz S Sofia canavial 090607 REFON.JPG|thumb|[[Sustainable biofuel#Sugarcane in Brazil|Sugarcane plantation]] to produce [[Ethanol fuel|ethanol]] in Brazil]]
There are many other sources of bioenergy that are more niche, or not yet viable at large scales. For instance, bioethanol could be [[Cellulosic ethanol|produced from the cellulosic parts]] of crops, rather than only the seed as is common today.<ref>{{Cite journal |last=Kramer |first=David |date=2022-07-01 |title=Whatever happened to cellulosic ethanol? |url=https://pubs.aip.org/physicstoday/article/75/7/22/2848574/Whatever-happened-to-cellulosic-ethanol |journal=Physics Today |language=en |volume=75 |issue=7 |pages=22–24 |doi=10.1063/PT.3.5036 |bibcode=2022PhT....75g..22K |issn=0031-9228}}</ref> [[Sweet sorghum]] may be a promising alternative source of bioethanol, due to its tolerance of a wide range of climates.<ref>{{Cite journal |last1=Ahmad Dar |first1=Rouf |last2=Ahmad Dar |first2=Eajaz |last3=Kaur |first3=Ajit |last4=Gupta Phutela |first4=Urmila |date=2018-02-01 |title=Sweet sorghum-a promising alternative feedstock for biofuel production |url=https://www.sciencedirect.com/science/article/pii/S1364032117314430 |journal=Renewable and Sustainable Energy Reviews |volume=82 |pages=4070–4090 |doi=10.1016/j.rser.2017.10.066 |bibcode=2018RSERv..82.4070A |issn=1364-0321}}</ref> [[Cow dung]] can be converted into methane.<ref>{{cite web |last1=Howard |first1=Brian |date=28 January 2020 |title=Turning cow waste into clean power on a national scale |url=https://thehill.com/changing-america/sustainability/energy/480316-turning-cow-waste-into-clean-power-on-a-national-scale |url-status=live |archive-url=https://web.archive.org/web/20200129180933/https://thehill.com/changing-america/sustainability/energy/480316-turning-cow-waste-into-clean-power-on-a-national-scale |archive-date=29 January 2020 |access-date=30 January 2020 |website=[[The Hill (newspaper)|The Hill]]}}</ref> There is also a great deal of research involving [[algal fuel]], which is attractive because algae is a non-food resource, grows around 20 times faster than most food crops, and can be grown almost anywhere.<ref name="ZhuLiHiltunen2018">{{cite journal | last1 = Zhu | first1 = Liandong | last2 = Li | first2 = Zhaohua | last3 = Hiltunen | first3 = Erkki | title = Microalgae Chlorella vulgaris biomass harvesting by natural flocculant: effects on biomass sedimentation, spent medium recycling and lipid extraction | journal = Biotechnology for Biofuels | date = 28 June 2018 | volume = 11 | issue = 1 | page = 183 | eissn = 1754-6834 | doi = 10.1186/s13068-018-1183-z | pmid = 29988300 | pmc = 6022341 | doi-access = free | bibcode = 2018BB.....11..183Z }}</ref>[[File:Soybeanbus.jpg |thumb|A bus fueled by [[biodiesel]]]]

=== Geothermal energy ===
{{Main|Geothermal energy|Geothermal power|Renewable thermal energy|Geothermal energy in the United States}}

[[File:NesjavellirPowerPlant edit2.jpg|thumb|Steam rising from the [[Nesjavellir Geothermal Power Station]] in Iceland]]
[[File:West Ford Flat Geothermal Cooling Tower.JPG|thumb|Geothermal plant at [[The Geysers]], California, US]]
[[File:Krafla geothermal power station wiki.jpg|thumb|[[Krafla Power Station|Krafla]], a [[geothermal power station]] in Iceland]]
{| class="wikitable"
! Installed capacity and other key design parameters
! Value and year
|-
| Global electricity power generation capacity || 14.9 GW (2023){{sfn|IRENA|2024|p=43}}
|-
| Global electricity power generation capacity annual growth rate || 3.4% (2014-2023)<ref>{{harvnb|IRENA|2024|p=43}}. Note: Compound annual growth rate 2014-2023.</ref>
|-
| Share of global electricity generation || <1% (2018)<ref name="IEA Electricity 2020">{{cite web |publisher=[[International Energy Agency]] |title=Electricity |date=2020 |at=Data Browser section, Electricity Generation by Source indicator |url=https://www.iea.org/fuels-and-technologies/electricity |access-date=17 July 2021 |archive-date=7 June 2021 |archive-url=https://web.archive.org/web/20210607024650/https://www.iea.org/fuels-and-technologies/electricity |url-status=live }}</ref>
|-
| Levelized cost per megawatt hour || USD 58.257 (2019){{sfn|NREL ATB|2021|loc=Geothermal}}
|-
| Primary technologies || Dry steam, flash steam, and binary cycle power stations
|-
| Main applications || Electricity, [[Geothermal heating|heating]]
|}

Geothermal energy is [[thermal energy]] (heat) extracted from the [[Earth's crust]]. It originates from several different [[Earth's internal heat budget#Sources of heat|sources]], of which the most significant is slow [[radioactive decay]] of minerals contained in the [[Internal structure of Earth|Earth's interior]],<ref name=":2" /> as well as some leftover heat from the [[Earth#Formation|formation of the Earth]].<ref name=":11">{{Citation |last=Clauser |first=Christoph |title=Earth's Heat and Temperature Field |date=2024 |work=Introduction to Geophysics |series=Springer Textbooks in Earth Sciences, Geography and Environment |pages=247–325 |url=https://link.springer.com/10.1007/978-3-031-17867-2_6 |access-date=2024-05-06 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-031-17867-2_6 |isbn=978-3-031-17866-5}}</ref> Some of the heat is generated near the Earth's surface in the crust, but some also flows from deep within the Earth from the [[Earth's mantle|mantle]] and [[Internal structure of Earth#Core|core]].<ref name=":11" /> Geothermal energy extraction is viable mostly in countries located on [[Plate tectonics|tectonic plate]] edges, where the Earth's hot mantle is more exposed.<ref name=":13">{{Citation |last1=Dincer |first1=Ibrahim |title=3.6 Geothermal Energy Production |date=2018 |work=Comprehensive Energy Systems |pages=252–303 |url=https://linkinghub.elsevier.com/retrieve/pii/B9780128095973003138 |access-date=2024-05-07 |publisher=Elsevier |language=en |doi=10.1016/b978-0-12-809597-3.00313-8 |isbn=978-0-12-814925-6 |last2=Ezzat |first2=Muhammad F.}}</ref> As of 2023, the United States has by far the most geothermal capacity (2.7 GW,<ref name=":12">{{Cite web |last1=Ritchie |first1=Hannah |last2=Rosado |first2=Pablo |last3=Roser |first3=Max |date=2023 |title=Data Page: Geothermal energy capacity |url=https://ourworldindata.org/grapher/installed-geothermal-capacity |access-date=2024-05-07 |website=Our World in Data}}</ref> or less than 0.2% of the country's total energy capacity<ref>{{Cite web |title=Electricity generation, capacity, and sales in the United States |url=https://www.eia.gov/energyexplained/electricity/electricity-in-the-us-generation-capacity-and-sales.php |access-date=2024-05-07 |website=[[U.S. Energy Information Administration]]}}</ref>), followed by Indonesia and the Philippines. Global capacity in 2022 was 15 GW.<ref name=":12" />

Geothermal energy can be either used directly to heat homes, as is common in Iceland where almost all of its energy is renewable, or to generate electricity. Iceland is a global leader in renewable energy, relying almost entirely on its abundant geothermal and hydroelectric resources derived from volcanic activity and glaciers.<ref>{{cite web |last1=Toussaint-Strauss |first1=Josh |last2=Talbot |first2=Jem |last3=Morresi |first3=Elena |last4=Assaf |first4=Ali |last5=Ambrose |first5=Jillian |last6=Baxter |first6=Ryan |last7=Glew |first7=Steve |title=Why unlimited green energy is closer than people think – video |url=https://www.theguardian.com/world/video/2025/may/01/why-unlimited-green-energy-is-closer-than-people-think-video |date=2025-05-01 |website=The Guardian |access-date=2025-05-01 |language=en}}</ref> At smaller scales, geothermal power can be generated with [[Ground source heat pump|geothermal heat pumps]], which can extract heat from ground temperatures of under {{Convert|30|C|F}}, allowing them to be used at relatively shallow depths of a few meters.<ref name=":13" /> Electricity generation requires large plants and ground temperatures of at least {{Convert|150|C|F}}. In some countries, electricity produced from geothermal energy accounts for a large portion of the total, such as Kenya (43%) and Indonesia (5%).<ref>{{Cite web |date=November 22, 2023 |title=Use of geothermal energy |url=https://www.eia.gov/energyexplained/geothermal/use-of-geothermal-energy.php |access-date=2024-05-07 |website=[[U.S. Energy Information Administration]]}}</ref>

Technical advances may eventually make geothermal power more widely available. For example, [[enhanced geothermal system]]s involve drilling around {{Convert|10|km|mi}} into the Earth, breaking apart hot rocks and extracting the heat using water. In theory, this type of geothermal energy extraction could be done anywhere on Earth.<ref name=":13" />