{{Short description|Electrical power generation from wind}} {{redirect|Wind energy|the academic journal|Wind Energy (journal)}} {{pp-pc|small=yes}} {{Use dmy dates|date=June 2020}} [[File: Wind power plants in Xinjiang, China.jpg|thumb|upright=1.6|Wind farm in Xinjiang, China]] thumb|World electricity production by source, 2000-2024 {{sustainable energy}}
'''Wind power''' is the use of wind energy to generate useful work. Historically, wind power was used by sails, windmills and windpumps, but today it is mostly used to generate electricity. This article deals only with wind power for electricity generation. Today, wind power is generated almost completely using wind turbines, generally grouped into wind farms and connected to the electrical grid.
In 2025, wind supplied about 2,700 TWh of electricity, which was over 8% of world electricity.<ref>https://ember-energy.org/data/electricity-data-explorer/?metric=absolute</ref> With about 100 GW added during 2021, mostly in China and the United States, global installed wind power capacity exceeded 800 GW.<ref name=":1">{{Cite web|title=Wind Power – Analysis|url=https://www.iea.org/reports/wind-power|access-date=2021-11-23|website=IEA|language=en-GB|archive-date=23 November 2021|archive-url=https://web.archive.org/web/20211123010357/https://www.iea.org/reports/wind-power|url-status=live}}</ref><ref name=":0">{{Cite web|title=Wind energy generation vs. installed capacity|url=https://ourworldindata.org/grapher/wind-energy-consumption-vs-installed-wind-energy-capacity|access-date=2021-11-23|website=Our World in Data|archive-date=19 October 2021|archive-url=https://web.archive.org/web/20211019062311/https://ourworldindata.org/grapher/wind-energy-consumption-vs-installed-wind-energy-capacity|url-status=live}}</ref><ref>{{Cite web |date=2022-03-25 |title=Global wind industry breezes into new record |url=https://www.energylivenews.com/2022/03/25/global-wind-industry-breezes-into-new-record/ |access-date=2022-04-02 |website=Energy Live News |language=en-US}}</ref> 30 countries generated more than a tenth of their electricity from wind power in 2024 and wind generation has nearly tripled since 2015.<ref name=ember2024>{{Cite web |date=2024-05-07 |title=Global Electricity Review 2025 |url=https://ember-energy.org/latest-insights/global-electricity-review-2025/ |access-date=2025-04-13 |website=Ember |language=en-US}}</ref> To help meet the Paris Agreement goals to limit climate change, analysts say it should expand much faster – by over 1% of electricity generation per year.<ref name=":2">{{Cite web|title=Expansion of wind and solar power too slow to stop climate change|url=https://www.sciencedaily.com/releases/2021/10/211014141949.htm|access-date=2021-11-24|website=ScienceDaily|language=en}}</ref>
Wind power is a sustainable, renewable energy source, and has a much smaller impact on the environment than burning fossil fuels. Wind power is variable, so it needs energy storage or other dispatchable generation energy sources to attain a reliable supply of electricity. Land-based (onshore) wind farms have a greater visual impact on the landscape than most other power stations per energy produced.<ref name="grantham">{{cite web|url=http://www.lse.ac.uk/GranthamInstitute/faqs/what-are-the-pros-and-cons-of-onshore-wind-energy|title=What are the pros and cons of onshore wind energy?|archive-url=https://web.archive.org/web/20190622123816/http://www.lse.ac.uk/GranthamInstitute/faqs/what-are-the-pros-and-cons-of-onshore-wind-energy/ |date=2018-01-12|archive-date=22 June 2019|work=Grantham Research Institute on Climate Change and the Environment, London School of Economics and Political Science}}</ref><ref name="energyfootprint">{{cite journal|first1=Nathan F.|last1=Jones|first2=Liba|last2=Pejchar|first3=Joseph M.|last3=Kiesecker|doi=10.1093/biosci/biu224|title=The Energy Footprint: How Oil, Natural Gas, and Wind Energy Affect Land for Biodiversity and the Flow of Ecosystem Services|journal=BioScience|volume=65|issue=3|date=2015-01-22|access-date=2022-11-09|pages=290–301|url=https://academic.oup.com/bioscience/article/65/3/290/236920|doi-access=free|issn=0006-3568}}</ref> Wind farms sited offshore have less visual impact and have higher capacity factors, although they are generally more expensive.<ref name=":1" /> Offshore wind power currently has a share of about 10% of new installations.<ref>{{cite web |date=19 March 2020 |title=Global Wind Report 2019 |url=https://gwec.net/global-wind-report-2019/ |access-date=28 March 2020 |publisher=Global Wind Energy Council |archive-date=24 June 2023 |archive-url=https://web.archive.org/web/20230624223720/https://gwec.net/global-wind-report-2019/ |url-status=dead }}</ref>
Wind power is one of the lowest-cost electricity sources per unit of energy produced. In many locations, new onshore wind farms are cheaper than new coal or gas plants.<ref name=":6" />
Regions in the higher northern and southern latitudes have the highest potential for wind power.<ref>{{cite web |title=Global Wind Atlas |url=http://science.globalwindatlas.info/datasets.html |archive-url=https://web.archive.org/web/20200224101415/http://science.globalwindatlas.info/datasets.html |archive-date=24 February 2020 |access-date=28 March 2020 |publisher=DTU Technical University of Denmark}}</ref> In most regions, wind power generation is higher in nighttime, and in winter when solar power output is low. So combinations of wind and solar power are suitable in many countries.<ref>{{Cite journal |last1=Nyenah |first1=Emmanuel |last2=Sterl |first2=Sebastian |last3=Thiery |first3=Wim |date=2022-05-01 |title=Pieces of a puzzle: solar-wind power synergies on seasonal and diurnal timescales tend to be excellent worldwide |journal=Environmental Research Communications |volume=4 |issue=5 |page=055011 |doi=10.1088/2515-7620/ac71fb |bibcode=2022ERCom...4e5011N |s2cid=249227821 |issn=2515-7620|doi-access=free }}</ref>
== Wind energy resources == [[File:Mean Wind Speed.png|thumb|Global map of wind speed at 100 meters on land and around coasts.<ref name="global_wind_atlas">{{cite web | url=https://globalwindatlas.info | title=Global Wind Atlas | publisher=Technical University of Denmark (DTU) | access-date=23 November 2021 | archive-date=18 January 2019 | archive-url=https://web.archive.org/web/20190118095006/https://www.globalwindatlas.info/ | url-status=live }}</ref>]] thumb|upright=1.6|Distribution of wind speed (red) and energy (blue) for all of 2002 at the Lee Ranch facility in Colorado. The histogram shows measured data, while the curve is the Rayleigh model distribution for the same average wind speed. thumb|Global map of wind power density potential<ref>{{Cite web |title=Global Wind Atlas |url=https://globalwindatlas.info/ |url-status=live |archive-url=https://web.archive.org/web/20190118095006/https://www.globalwindatlas.info/ |archive-date=18 January 2019 |access-date=14 June 2019}}</ref> Wind is air movement in the Earth's atmosphere. In a unit of time, say 1 second, the volume of air that had passed an area <math>A</math> is <math>Av</math>. If the air density is <math>\rho</math>, the flow rate of this volume of air is <math>\tfrac{M}{\Delta t}=\rho Av</math>, and the power transfer, or energy transfer per second is <math>P =\tfrac {1}{2}\tfrac{M}{\Delta t} v^{2}= \tfrac {1}{2}\rho A v^{3}</math>. Wind power is thus ''proportional'' to the ''third power'' of the wind speed; the available power increases eightfold when the wind speed doubles. Change of wind speed by a factor of 2.1544 increases the wind power by one order of magnitude (multiply by 10).
The global wind kinetic energy averaged approximately 1.50 MJ/m<sup>2</sup> over the period from 1979 to 2010, 1.31 MJ/m<sup>2</sup> in the Northern Hemisphere with 1.70 MJ/m<sup>2</sup> in the Southern Hemisphere. The atmosphere acts as a thermal engine, absorbing heat at higher temperatures, releasing heat at lower temperatures. The process is responsible for the production of wind kinetic energy at a rate of 2.46 W/m<sup>2</sup> thus sustaining the circulation of the atmosphere against friction.<ref>{{cite journal|url=http://dash.harvard.edu/bitstream/handle/1/13919173/A%2032-year%20Perspective%20on%20the%20Origin%20of%20Wind%20Energy%20in%20a%20warming%20Climate.pdf?sequence=1|title=A 32-year perspective on the origin of wind energy in a warming climate|journal=Renewable Energy|volume=77|pages=482–92|year=2015|doi=10.1016/j.renene.2014.12.045|last1=Huang|first1=Junling|last2=McElroy|first2=Michael B|bibcode=2015REne...77..482H |s2cid=109273683 |access-date=6 February 2015|archive-date=6 February 2015|archive-url=https://web.archive.org/web/20150206044746/http://dash.harvard.edu/bitstream/handle/1/13919173/A%2032-year%20Perspective%20on%20the%20Origin%20of%20Wind%20Energy%20in%20a%20warming%20Climate.pdf?sequence=1|url-status=live}}</ref>
Through wind resource assessment, it is possible to estimate wind power potential globally, by country or region, or for a specific site. The Global Wind Atlas provided by the Technical University of Denmark in partnership with the World Bank provides a global assessment of wind power potential.<ref name="global_wind_atlas" /><ref>[https://www.worldbank.org/en/news/press-release/2017/11/28/mapping-the-worlds-wind-energy-potential Mapping the World's Wind Energy Potential] {{Webarchive|url=https://web.archive.org/web/20180925180559/https://www.worldbank.org/en/news/press-release/2017/11/28/mapping-the-worlds-wind-energy-potential |date=25 September 2018 }} ''World Bank'', 28 November 2017.</ref><ref>[http://www.vindenergi.dtu.dk/english/news/2017/11/new-global-wind-atlas-to-be-presented-at-windeurope-conference New Global Wind Atlas to be presented at WindEurope Conference] {{Webarchive|url=https://web.archive.org/web/20180925180408/http://www.vindenergi.dtu.dk/english/news/2017/11/new-global-wind-atlas-to-be-presented-at-windeurope-conference |date=25 September 2018 }} ''Technical University of Denmark'', 21 November 2017.</ref> Unlike 'static' wind resource atlases which average estimates of wind speed and power density across multiple years, tools such as Renewables.ninja provide time-varying simulations of wind speed and power output from different wind turbine models at an hourly resolution.<ref>{{cite journal|last1= Staffell |first1= Iain |last2= Pfenninger |first2= Stefan |title=Using bias-corrected reanalysis to simulate current and future wind power output|date=1 November 2016|journal= Energy |volume = 114 |pages = 1224–39 |doi = 10.1016/j.energy.2016.08.068|doi-access = free|bibcode= 2016Ene...114.1224S |hdl= 20.500.11850/120087 |hdl-access= free }}</ref> More detailed, site-specific assessments of wind resource potential can be obtained from specialist commercial providers, and many of the larger wind developers have in-house modeling capabilities.
The total amount of economically extractable power available from the wind is considerably more than present human power use from all sources.<ref>{{cite web|url=http://www.claverton-energy.com/how-much-wind-energy-is-there-brian-hurley-wind-site-evaluation-ltd.html|title=How Much Wind Energy is there?|last=Hurley|first=Brian|publisher=Claverton Group|access-date=8 April 2012|archive-date=15 May 2012|archive-url=https://web.archive.org/web/20120515154047/http://www.claverton-energy.com/how-much-wind-energy-is-there-brian-hurley-wind-site-evaluation-ltd.html|url-status=live}}</ref> The strength of wind varies, and an average value for a given location does not alone indicate the amount of energy a wind turbine could produce there.
To assess prospective wind power sites, a probability distribution function is often fit to the observed wind speed data.<ref>{{cite journal | url= http://www.savenkov.org/publications/Savenkov_on_the_truncated_weibull_distribution_2009.pdf |author=Savenkov, M |year=2009 |title=On the truncated weibull distribution and its usefulness in evaluating potential wind (or wave) energy sites |journal=University Journal of Engineering and Technology |volume=1 |issue=1 |pages=21–25 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20150222120957/http://www.savenkov.org/publications/Savenkov_on_the_truncated_weibull_distribution_2009.pdf |archive-date=22 February 2015}}</ref> Different locations will have different wind speed distributions. The Weibull model closely mirrors the actual distribution of hourly/ten-minute wind speeds at many locations. The Weibull factor is often close to 2 and therefore a Rayleigh distribution can be used as a less accurate, but simpler model.<ref>{{cite web | url=http://xn--drmstrre-64ad.dk/wp-content/wind/miller/windpower%20web/en/tour/wres/weibull.htm | title=Describing Wind Variations: Weibull Distribution | publisher=Danish Wind Industry Association | access-date=8 July 2021 | archive-date=2 August 2021 | archive-url=https://web.archive.org/web/20210802193222/http://xn--drmstrre-64ad.dk/wp-content/wind/miller/windpower%20web/en/tour/wres/weibull.htm | url-status=live }}</ref>
== Wind farms == {{main|Wind farm|List of onshore wind farms}}
{| class="wikitable floatright sortable" |+ Large onshore wind farms |- ! Wind farm ! Capacity<br />(MW) ! Country ! class="unsortable" | Refs |- | Gansu Wind Farm || align="center" | 7,965 || {{Flagu|China}} || <ref>Watts, Jonathan & Huang, Cecily. [https://www.theguardian.com/world/2012/mar/19/china-windfarms-renewable-energy Winds Of Change Blow Through China As Spending On Renewable Energy Soars] {{Webarchive|url=https://web.archive.org/web/20130615063412/http://www.guardian.co.uk/world/2012/mar/19/china-windfarms-renewable-energy |date=15 June 2013 }}, ''The Guardian'', 19 March 2012, revised on 20 March 2012. Retrieved 4 January 2012.</ref> |- | Muppandal Wind Farm|| align="center" | 1,500 || {{Flagu|India}} || <ref>{{cite web|url=http://www.thewindpower.net/windfarm_en_449.php|title=Muppandal (India)|publisher=thewindpower.net|access-date=21 November 2015|archive-date=14 August 2014|archive-url=https://web.archive.org/web/20140814194848/http://www.thewindpower.net/windfarm_en_449.php|url-status=live}}</ref> |- | Alta (Oak Creek-Mojave) || align="center" | 1,320 || {{Flagu|United States}} ||<ref>[http://www.terra-genpower.com/News/Terra-Gen-Power-Announces-Closing-of-$650-Million-.aspx Terra-Gen Press Release] {{webarchive|url=https://web.archive.org/web/20120510173856/http://www.terra-genpower.com/News/Terra-Gen-Power-Announces-Closing-of-%24650-Million-.aspx |date=10 May 2012}}, 17 April 2012</ref> |- | Jaisalmer Wind Park || align="center" | 1,064 || {{Flagu|India}} ||<ref>[http://www.business-standard.com/india/news/suzlon-creates-country/s-largest-wind-park/164779/on Started in August 2001, the Jaisalmer based facility crossed 1,000 MW capacity to achieve this milestone] {{Webarchive|url=https://web.archive.org/web/20121001062608/http://www.business-standard.com/india/news/suzlon-creates-country/s-largest-wind-park/164779/on |date=1 October 2012 }}. Business-standard.com (11 May 2012). Retrieved on 20 July 2016.</ref> |}
A wind farm is a group of wind turbines in the same location. A large wind farm may consist of several hundred individual wind turbines distributed over an extended area. The land between the turbines may be used for agricultural or other purposes. A wind farm may also be located offshore. Almost all large wind turbines have the same design — a horizontal axis wind turbine having an upwind rotor with 3 blades, attached to a nacelle on top of a tall tubular tower.
In a wind farm, individual turbines are interconnected with a medium voltage (often 34.5 kV) power collection system<ref>{{cite web|url=https://ewh.ieee.org/r3/atlanta/ias/Wind%20Farm%20Electrical%20Systems.pdf|title=Wind Farm Electrical Systems|access-date=2020-07-11|archive-date=18 March 2021|archive-url=https://web.archive.org/web/20210318210221/https://ewh.ieee.org/r3/atlanta/ias/Wind%20Farm%20Electrical%20Systems.pdf|url-status=live}}</ref> and communications network. In general, a distance of 7D (7 times the rotor diameter of the wind turbine) is set between each turbine in a fully developed wind farm.<ref>{{Cite journal|last1=Meyers|first1=Johan|last2=Meneveau|first2=Charles|date=1 March 2012|title=Optimal turbine spacing in fully developed wind farm boundary layers|journal=Wind Energy|volume=15|issue=2|pages=305–17|doi=10.1002/we.469|bibcode=2012WiEn...15..305M|url=https://lirias.kuleuven.be/handle/123456789/331240|url-access=subscription}}</ref> At a substation, this medium-voltage electric current is increased in voltage with a transformer for connection to the high voltage electric power transmission system.<ref>{{cite web|url=https://www.windpowerengineering.com/projects/making-modern-offshore-substation/|title=Making of the modern offshore substation|website=Windpower Engineering & Development|language=en-US|access-date=14 June 2019|archive-date=24 November 2021|archive-url=https://web.archive.org/web/20211124094304/https://www.windpowerengineering.com/making-modern-offshore-substation/|url-status=live}}</ref>
=== Generator characteristics and stability ===
Most modern turbines use variable speed generators combined with either a partial or full-scale power converter between the turbine generator and the collector system, which generally have more desirable properties for grid interconnection and have low-voltage ride-through capabilities.<ref name="huang">{{Cite book|last1=Falahi|first1=G.|last2=Huang|first2=A.|title=IECON 2014 – 40th Annual Conference of the IEEE Industrial Electronics Society |chapter=Low voltage ride through control of modular multilevel converter based HVDC systems |date=1 October 2014|pages=4663–68|doi=10.1109/IECON.2014.7049205|isbn=978-1-4799-4032-5|s2cid=3598534}}</ref> Modern turbines use either doubly fed electric machines with partial-scale converters or squirrel-cage induction generators or synchronous generators (both permanently and electrically excited) with full-scale converters.<ref>{{cite journal|doi=10.1016/j.enconman.2014.08.037|title=The state of the art of wind energy conversion systems and technologies: A review|journal=Energy Conversion and Management|volume=88|page=332|year=2014|last1=Cheng|first1=Ming|last2=Zhu|first2=Ying|bibcode=2014ECM....88..332C }}</ref> Black start is possible<ref>{{Cite web |date=2020-11-03 |title=ScottishPower in 'pioneering world first' after wind farm black-out boost |url=https://www.scotsman.com/business/scottishpower-in-pioneering-world-first-after-wind-farm-black-out-boost-3023563 |access-date=2022-09-19 |website=www.scotsman.com |language=en}}</ref> and is being further developed for places (such as Iowa) which generate most of their electricity from wind.<ref>{{Cite web |title=As the grid adds wind power, researchers have to reengineer recovery from power outages |url=https://www.sciencedaily.com/releases/2022/05/220531181931.htm |access-date=2022-09-19 |website=ScienceDaily |language=en}}</ref>
Transmission system operators will supply a wind farm developer with a grid code to specify the requirements for interconnection to the transmission grid. This will include the power factor, the constancy of frequency, and the dynamic behaviour of the wind farm turbines during a system fault.<ref>{{Cite journal | last1 = Demeo | first1 = E.A. | last2 = Grant | first2 = W. | last3 = Milligan | first3 = M.R. | last4 = Schuerger | first4 = M.J. | year = 2005 | title = Wind plant integration | journal = IEEE Power and Energy Magazine| volume = 3 | issue = 6 | pages = 38–46 | doi = 10.1109/MPAE.2005.1524619| s2cid = 12610250 }}</ref><ref>{{Cite journal | last1 = Zavadil | first1 = R. | last2 = Miller | first2 = N. | last3 = Ellis | first3 = A. | last4 = Muljadi | first4 = E. | year = 2005 | title = Making connections | journal = IEEE Power and Energy Magazine| volume = 3 | issue = 6 | pages = 26–37 | doi = 10.1109/MPAE.2005.1524618| bibcode = 2005IPEnM...3f..26Z | s2cid = 3037161 }}</ref>
=== Offshore wind power === {{multiple image |total_width=500 |image1=Agucadoura WindFloat Prototype.jpg | caption1= The world's second full-scale floating wind turbine (and first to be installed without the use of heavy-lift vessels), WindFloat, operating at rated capacity (2 MW) approximately 5 km offshore of Póvoa de Varzim, Portugal
|image2= 20210830 Windfarm power generation capacity - offshore capacity, and total needed.svg| caption2= Offshore windfarms, including floating windfarms, provide a small but growing fraction of total windfarm power generation. Such power generation capacity must grow substantially to help meet the IEA's Net Zero by 2050 pathway to combat climate change.<ref name=Guardian_20210829>{{cite news |last1=Rosa-Aquino |first1=Paola |title=Floating wind turbines could open up vast ocean tracts for renewable power |url=https://www.theguardian.com/environment/2021/aug/29/floating-wind-turbines-ocean-renewable-power |work=The Guardian |date=29 August 2021 |archive-url=https://web.archive.org/web/20210830162300/https://www.theguardian.com/environment/2021/aug/29/floating-wind-turbines-ocean-renewable-power |archive-date=30 August 2021 |url-status=live }}</ref> }} {{Main|Offshore wind power|List of offshore wind farms}}
Offshore wind power is wind farms in large bodies of water, usually the sea. These installations can use the more frequent and powerful winds that are available in these locations and have less visual impact on the landscape than land-based projects. However, the construction and maintenance costs are considerably higher.<ref>{{cite web|url=http://www.renewables-info.com/drawbacks_and_benefits/offshore_wind_power_%E2%80%93_advantages_and_disadvantages.html|title=Offshore wind power – Advantages and disadvantages|last=Hulazan|first=Ned|date=16 February 2011|publisher=Renewable Energy Articles|access-date=9 April 2012|archive-date=13 October 2018|archive-url=https://web.archive.org/web/20181013053638/http://www.renewables-info.com/drawbacks_and_benefits/offshore_wind_power_%E2%80%93_advantages_and_disadvantages.html|url-status=live}}</ref><ref>{{cite web|url=http://www.windpowermonthly.com/go/europe/news/1021043/Cutting-cost-offshore-wind-energy/|title=Cutting the cost of offshore wind energy|last=Millborrow|first=David|date=6 August 2010|website=Wind Power Monthly|publisher=Haymarket|access-date=10 April 2012|archive-date=2 December 2012|archive-url=https://web.archive.org/web/20121202035902/http://www.windpowermonthly.com/go/europe/news/1021043/Cutting-cost-offshore-wind-energy/|url-status=live}}</ref>
As of November 2021, the Hornsea Wind Farm in the United Kingdom is the largest offshore wind farm in the world at 1,218 MW.<ref name="hornsea">{{Cite web|date=2020-01-30|title=World's Largest Offshore Wind Farm Fully Up and Running|url=https://www.offshorewind.biz/2020/01/30/worlds-largest-offshore-wind-farm-fully-up-and-running/|url-status=live|archive-url=https://web.archive.org/web/20200131051635/https://www.offshorewind.biz/2020/01/30/worlds-largest-offshore-wind-farm-fully-up-and-running/|archive-date=31 January 2020|access-date=2020-02-03|website=Offshore Wind|language=en-US}}</ref>
=== Collection and transmission network === Near offshore wind farms may be connected by AC and far offshore by HVDC.<ref>{{Cite web |last=Action |first=BMWK-Federal Ministry for Economics Affairs and Climate |title=Connecting offshore wind energy to the grid |url=https://www.bmwk.de/Redaktion/EN/Artikel/Energy/connecting-offshore-wind-energy-to-the-grid.html |access-date=2023-01-20 |website=www.bmwk.de |language=en}}</ref>
Wind power resources are not always located near areas with a high population density. As transmission lines become longer, the losses associated with power transmission increase, as modes of losses at lower lengths are exacerbated and new modes of losses are no longer negligible as the length is increased; making it harder to transport large loads over large distances.<ref>Power System Analysis and Design. Glover, Sarma, Overbye/ 5th Edition</ref>
When the transmission capacity does not meet the generation capacity, wind farms are forced to produce below their full potential or stop running altogether, in a process known as curtailment. While this leads to potential renewable generation left untapped, it prevents possible grid overload or risk to reliable service.<ref name=maine>[http://www.pressherald.com/news/there-is-a-problem-with wind-power-in-maine_2013-08-04.html?pagenum=full Inadequate transmission lines keeping some Maine wind power off the grid – The Portland Press Herald / Maine Sunday Telegram] {{Webarchive|url=https://web.archive.org/web/20211124094412/https://www.pressherald.com/2013/08/04/there-is-a-problem-withwind-power-in-maine_2013-08-04/ |date=24 November 2021 }}. Pressherald.com (4 August 2013). Retrieved on 20 July 2016.</ref>
One of the major challenges to wind power grid integration in some countries is developing new transmission lines to carry power from wind farms, which are often in remote lowly populated areas due to availability of wind, to high load locations where population density is higher.<ref>{{Cite web|date=2021-04-07|title=From West to East: The Charged Challenge of Delivering Electricity|url=https://www.chinabusinessreview.com/from-west-to-east-the-charged-challenge-of-delivering-electricity/|access-date=2021-11-24|website=China Business Review|language=en-US}}</ref> Any existing transmission lines in remote locations may not have been designed for the transport of large amounts of energy.<ref name="nytimes.com">Wald, Matthew (26 August 2008) [https://www.nytimes.com/2008/08/27/business/27grid.html?pagewanted=all&_r=0 Wind Energy Bumps Into Power Grid's Limits] {{Webarchive|url=https://web.archive.org/web/20170701110101/http://www.nytimes.com/2008/08/27/business/27grid.html?pagewanted=all&_r=0 |date=1 July 2017 }}. ''New York Times''</ref> In particular geographic regions, peak wind speeds may not coincide with peak demand for electrical power, whether offshore or onshore. A possible future option may be to interconnect widely dispersed geographic areas with an HVDC super grid.<ref>{{Cite web|last=Barnard|first=Michael|date=2021-11-11|title=Breaking News: China & USA Joint Declaration On Climate Action Collaboration|url=https://cleantechnica.com/2021/11/11/breaking-news-china-and-usa-joint-declaration-on-climate-action-collaboration/|access-date=2021-11-23|website=CleanTechnica|language=en-US|archive-date=12 November 2021|archive-url=https://web.archive.org/web/20211112143817/https://cleantechnica.com/2021/11/11/breaking-news-china-and-usa-joint-declaration-on-climate-action-collaboration/|url-status=live}}</ref>
== Wind power capacity and production == {{Main|Wind power by country|Wind power industry}}
In 2024, wind supplied over 2,494 TWh of electricity, which was 8.1% of world electricity.<ref name=ember2024/>
=== Growth trends === {{multiple image | align=center |total_width=675 | image1= 2010- Power capacity by technology - Dec 2022 International Energy Agency.svg |caption1= Renewable energy sources, especially solar photovoltaic and wind power, are providing an increasing share of power capacity.<ref name="IEA_20221205">{{cite web |title=Share of cumulative power capacity by technology, 2010–2027 |url=https://www.iea.org/data-and-statistics/charts/share-of-cumulative-power-capacity-by-technology-2010-2027 |website=IEA.org |publisher=International Energy Agency (IEA) |archive-url=https://web.archive.org/web/20230204170647/https://www.iea.org/data-and-statistics/charts/share-of-cumulative-power-capacity-by-technology-2010-2027 |archive-date=4 February 2023 |date=5 December 2022 |url-status=live}} Source states "Fossil fuel capacity from IEA (2022), ''World Energy Outlook 2022''. IEA. Licence: CC BY 4.0."</ref> | image2= Wind energy generation by region, OWID.svg |caption2=Wind energy generation by region<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> | image3= Wind generation by country.svg |caption3=Wind generation by country }} {{clear}}
<!-- START OF GW SCALE COUNTRIES CHART --> {| style="float:right" |- | {{Image frame |width = 250 |align=right |pos=bottom |content= <div style="margin:0 5px -40px -70px; font-size:0.85em;"> <div style="font-size: 120%; font-weight: bold; padding: 10px 0 12px 90px;">Number of countries with wind capacities in the gigawatt-scale by year</div> {{ #invoke:Chart | bar-chart | width = 280 | height = 280 | stack = 1 | group 1 = 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 1 : 1 : 1 : 1 : 1 : 2 : 2 : 2 : 2 | group 2 = 1 : 1 : 3 : 3 : 4 : 5 : 5 : 5 : 5 : 6 : 5 : 7 : 8 : 8 : 9 : 8 : 8 : 10 : 11 | group 3 = 6 : 10 : 10 : 10 : 12 : 12 : 15 : 17 : 19 : 18 : 18 : 18 : 20 : 21 : 22 : 25 : 25 : 26 : 27 | colors = #990000 : #FFaa77 : #FFccaa | group names = installed more than 100 GW : installed between 10 and 100 GW : installed between 1 and 10 GW | units suffix = _countries | hide group legends = 1 | x legends = : 2005 : : : : : 2010: : : : : 2015 : : : : : 2020 : : }}</div> |caption =Growing number of wind gigawatt-markets {{Collapsible list | title = {{legend2|#FFccaa|border=1px solid #ccccaa|Above 1-GW mark}} |{{aligned table | cols=5 | style=width: 50%; text-align: left; font-size: 100%; margin-left: 22px; | 2022 | {{flagicon|CRO}} | {{flagicon|KAZ}} | | | 2021 | {{flagicon|RUS}} | {{flagicon|TAI}} | {{flagicon|VIE}} | | 2019 | {{flagicon|ARG}} | {{flagicon|THA}} | {{flagicon|UKR}} | | 2018 | {{flagicon|PAK}} | {{flagicon|EGY}} | | | 2017 | {{flagicon|NOR}} | | | | 2016 | {{flagicon|CHI}} | {{flagicon|URU}} | {{flagicon|KOR}} | | 2015 | {{flagicon|SA}} | {{flagicon|FIN}} | | | 2012 | {{flagicon|MEX}} | {{flagicon|ROM}} | | | 2011 | {{flagicon|BRA}} | {{flagicon|BEL}} | | | 2010 | {{flagicon|AUT}} | {{flagicon|POL}} | {{flagicon|TUR}} | | 2009 | {{flagicon|GRE}} | | | | 2008 | {{flagicon|IRE}} | {{flagicon|AUS}} | {{flagicon|SWE}} | | 2006 | {{flagicon|CAN}} | {{flagicon|FRA}} | | | 2005 | {{flagicon|UK}} | {{flagicon|CHN}} | {{flagicon|JP}} | {{flagicon|POR}} | 2004 | {{flagicon|NED}} | {{flagicon|ITA}} | | | 1999 | {{flagicon|SPA}} | {{flagicon|IND}} | | | 1997 | {{flagicon|DEN}} | | | | 1995 | {{flagicon|GER}} | | | | 1986 | {{flagicon|USA}} | | | }}<!-- end of table--> }}<!-- end of list --> {{Collapsible list | title = {{legend2|#FFaa77|border=1px solid #ccaa77|Above 10-GW mark}} |{{aligned table | cols=5 | style=width: 50%; text-align: left; font-size: 100%; margin-left: 22px; | 2022 | {{flagicon|AUS}}<!-- https://en.wikipedia.org/wiki/Wind_power_by_country --> | | | | 2021 | {{flagicon|SWE}}<!-- https://en.wikipedia.org/wiki/Wind_power_by_country --> | {{flagicon|TUR}}<!-- https://windeurope.org/newsroom/news/turkey-reaches-10-gw-wind-energy-milestone/ --> | | | 2018 | {{flagicon|ITA}}<!-- https://www.qualenergia.it/articoli/quanti-impianti-eolici-ci-sono-in-italia/ --> | | | | 2016 | {{flagicon|BRA}} | | | | 2015 | {{flagicon|CAN}} | {{flagicon|FRA}} | | | 2013 | {{flagicon|UK}} | | | | 2009 | {{flagicon|IND}} | | | | 2008 | {{flagicon|CHN}} | | | | 2006 | {{flagicon|USA}} | {{flagicon|SPA}} | | | 2002 | {{flagicon|GER}} | | | }}<!-- end of table--> }}<!-- end of list --> {{Collapsible list | title = {{legend2|#990000|border=1px solid #200000|Above 100-GW mark}} |{{aligned table | cols=5 | style=width: 50%; text-align: left; font-size: 100%; margin-left: 22px; | 2019 | {{flagicon|USA}} | | | | 2014 | {{flagicon|CHN}} | | | }}<!-- end of table--> }}<!-- end of list --> }} |}
To help meet the Paris Agreement's goals to limit climate change, analysts say it should expand much faster than it currently is – by over 1% of electricity generation per year.<ref name=":2" /> Expansion of wind power is being hindered by fossil fuel subsidies.<ref name=":3">{{Cite web|date=2021-10-29|title=UNDP: More spent on fossil fuel subsidies than fighting poverty|url=https://www.un.org/africarenewal/magazine/november-2021/undp-more-spent-fossil-fuel-subsidies-fighting-poverty|access-date=2021-11-24|website=Africa Renewal|language=en}}</ref><ref name=":4">{{Cite web|title=Fossil fuel subsidies and renewable energies in MENA: An oxymoron?|last=Mohseni-Cheraghlou|first=Amin|date=2021-02-23|url=https://www.mei.edu/publications/fossil-fuel-subsidies-and-renewable-energies-mena-oxymoron|access-date=2021-11-24|work=Middle East Institute|language=en}}</ref><ref name=":5">{{Cite news|date=2021-11-15|title=COP26: How much is spent supporting fossil fuels and green energy?|language=en-GB|work=BBC News|url=https://www.bbc.com/news/59233799|access-date=2021-11-24}}</ref>
The actual amount of electric power that wind can generate is calculated by multiplying the nameplate capacity by the capacity factor, which varies according to equipment and location. Estimates of the capacity factors for wind installations are in the range of 35% to 44%.<ref>Rick Tidball and others, [http://www.nrel.gov/docs/fy11osti/48595.pdf "Cost and Performance Assumptions for Modeling Electricity Generation Technologies"] {{Webarchive|url=https://web.archive.org/web/20140821101932/http://www.nrel.gov/docs/fy11osti/48595.pdf |date=21 August 2014 }}, US National Renewable Energy Laboratory, November 2010, p.63.</ref>
===Capacity factor=== Since wind speed is not constant, a wind farm's annual energy production is never as much as the sum of the generator nameplate ratings multiplied by the total hours in a year. The ratio of actual productivity in a year to this theoretical maximum is called the capacity factor. Online data is available for some locations, and the capacity factor can be calculated from the yearly output.<ref name="MassMaritime">[http://view2.fatspaniel.net/FST/Portal/LighthouseElectrical/maritime/HostedAdminView.html Massachusetts Maritime Academy — Bourne, Mass] {{webarchive |url=https://web.archive.org/web/20070211113537/http://view2.fatspaniel.net/FST/Portal/LighthouseElectrical/maritime/HostedAdminView.html |date=11 February 2007}} This 660 kW wind turbine has a capacity factor of about 19%.</ref><ref name="iesoOntarioWind">[http://www.ieso.ca/imoweb/marketdata/windpower.asp Wind Power in Ontario] {{webarchive|url=https://web.archive.org/web/20140810202450/http://www.ieso.ca/imoweb/marketdata/windpower.asp |date=10 August 2014}} These wind farms have capacity factors of about 28–35%.</ref>
=== Penetration === <!-- Deleted image removed: thumb|right|upright=1.6|Share of electricity production from wind, 2024<ref>{{cite web |title=Share of electricity production from wind |url=https://ourworldindata.org/grapher/share-electricity-wind |website=Our World in Data |access-date=27 June 2025}}</ref> --> [[File:2024-2025 Change in electricity sources and demand.svg |thumb |Growth in solar and wind power from the first half of 2024 to the first half of 2025 increased more than the growth in overall demand for electricity, reducing reliance on fossil fuels and helping to curb greenhouse gas emissions.<ref name=Ember_20251007>{{cite web |last1=Wiatros-Motyka |first1=Małgorzata |last2=Rangelova |first2=Kostantsa |title=Global Electricity Mid-Year Insights 2025 |url=https://ember-energy.org/app/uploads/2025/10/Global-Electricity-Mid-Year-Insights-2025-PDF.pdf |website=Ember-Energy.org |publisher=Ember |archive-url=https://web.archive.org/web/20251204182020/https://ember-energy.org/app/uploads/2025/10/Global-Electricity-Mid-Year-Insights-2025-PDF.pdf |archive-date=4 December 2025 |page=4 |date=7 October 2025 |url-status=live |quote=Solar and wind outpaced demand growth in the first half of 2025. ... This led to renewables overtaking coal’s share in the global mix and prevented further increases in CO2 emissions from the power sector.}}</ref>]] Wind energy penetration is the fraction of energy produced by wind compared with the total generation. Wind power's share of worldwide electricity usage in 2021 was almost 7%,<ref>{{cite web |url=https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy/renewable-energy.html.html#wind-energy |publisher=BP |access-date=15 January 2020 |title=Renewable energy |work=bp global |archive-date=6 November 2020 |archive-url=https://web.archive.org/web/20201106215146/https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy/renewable-energy.html.html#wind-energy |url-status=live }}</ref> up from 3.5% in 2015.<ref>{{cite web|title=BP Statistical Review of World Energy June 2016 – Electricity|url=http://www.bp.com/content/dam/bp/pdf/energy-economics/statistical-review-2016/bp-statistical-review-of-world-energy-2016-electricity.pdf|publisher=BP|access-date=12 September 2016|archive-url=https://web.archive.org/web/20160910023428/http://www.bp.com/content/dam/bp/pdf/energy-economics/statistical-review-2016/bp-statistical-review-of-world-energy-2016-electricity.pdf|archive-date=10 September 2016}}</ref><ref>{{cite web |title=BP Statistical Review of World Energy June 2016 – Renewable energy |url=http://www.bp.com/content/dam/bp/pdf/energy-economics/statistical-review-2016/bp-statistical-review-of-world-energy-2016-renewable-energy.pdf |publisher=BP |access-date=12 September 2016 |archive-date=18 August 2016 |archive-url=https://web.archive.org/web/20160818051801/http://www.bp.com/content/dam/bp/pdf/energy-economics/statistical-review-2016/bp-statistical-review-of-world-energy-2016-renewable-energy.pdf |url-status=live }}</ref>
There is no generally accepted maximum level of wind penetration. The limit for a particular grid will depend on the existing generating plants, pricing mechanisms, capacity for energy storage, demand management, and other factors. An interconnected electric power grid will already include reserve generating and transmission capacity to allow for equipment failures. This reserve capacity can also serve to compensate for the varying power generation produced by wind stations. Studies have indicated that 20% of the total annual electrical energy consumption may be incorporated with minimal difficulty.<ref name=tacklingUS> {{cite web | url=http://ases.org/images/stories/file/ASES/climate_change.pdf | title=Tackling Climate Change in the U.S | archive-url=https://web.archive.org/web/20081126220129/http://www.ases.org/images/stories/file/ASES/climate_change.pdf | archive-date=26 November 2008 | publisher= American Solar Energy Society | date=January 2007 | access-date=5 September 2007}} </ref> These studies have been for locations with geographically dispersed wind farms, some degree of dispatchable energy or hydropower with storage capacity, demand management, and interconnected to a large grid area enabling the export of electric power when needed. Electrical utilities continue to study the effects of large-scale penetration of wind generation on system stability.<ref>{{Cite web|date=2021-12-08|title=New research shows Wind turbines, configured right, could provide grid stability|url=https://energypost.eu/new-research-shows-wind-turbines-configured-right-could-provide-grid-stability/|archive-url=https://web.archive.org/web/20211208104749/https://energypost.eu/new-research-shows-wind-turbines-configured-right-could-provide-grid-stability/|url-status=usurped|archive-date=8 December 2021|access-date=2022-01-25|website=Energy Post|language=en-GB}}</ref>
A wind energy penetration figure can be specified for different duration of time but is often quoted annually. To generate almost all electricity from wind annually requires substantial interconnection to other systems, for example some wind power in Scotland is sent to the rest of the British grid.<ref>{{Cite news |date=2022-04-01 |title=Low winds blamed for fall in Scotland's renewable energy production |language=en-GB |work=BBC News |url=https://www.bbc.com/news/uk-scotland-60948639 |access-date=2023-01-20}}</ref> On a monthly, weekly, daily, or hourly basis—or less—wind might supply as much as or more than 100% of current use, with the rest stored, exported or curtailed. The seasonal industry might then take advantage of high wind and low usage times such as at night when wind output can exceed normal demand. Such industry might include the production of silicon, aluminum,<ref>Andresen, Tino. "[https://www.bloomberg.com/news/articles/2014-11-27/molten-aluminum-lakes-offer-power-storage-for-german-wind-farms Molten Aluminum Lakes Offer Power Storage for German Wind Farms] {{Webarchive|url=https://web.archive.org/web/20170407022716/https://www.bloomberg.com/news/articles/2014-11-27/molten-aluminum-lakes-offer-power-storage-for-german-wind-farms |date=7 April 2017 }}" ''Bloomberg'', 27 October 2014.</ref> steel, or natural gas, and hydrogen, and using future long-term storage to facilitate 100% energy from variable renewable energy.<ref>{{cite web |author=Luoma, Jon R. |url=http://e360.yale.edu/feature/the_challenge_for_green_energy_how_to_store_excess_electricity/2170/ |title=The Challenge for Green Energy: How to Store Excess Electricity |publisher=E360.yale.edu |date=13 July 2001 |access-date=8 November 2012 |archive-date=6 April 2013 |archive-url=https://web.archive.org/web/20130406032321/http://e360.yale.edu/feature/the_challenge_for_green_energy_how_to_store_excess_electricity/2170/ |url-status=live }}</ref><ref>{{cite web|url=http://revmodo.com/2012/08/23/power-to-gas-technology-turns-excess-wind-energy-into-natural-gas/ |archive-url=https://web.archive.org/web/20121005211707/http://revmodo.com/2012/08/23/power-to-gas-technology-turns-excess-wind-energy-into-natural-gas/ |archive-date=5 October 2012 |author=Buczynski, Beth |title=Power To Gas Technology Turns Excess Wind Energy Into Natural Gas |publisher=Revmodo.com |date=23 August 2012}}</ref>{{Better source needed|reason=too old|date=January 2023}} Homes and businesses can also be programmed to vary electricity demand,<ref>{{Cite web |title=What is demand-side response |url=https://en.energinet.dk/electricity/green-electricity/demand-side-response/what-is-demand-side-response/ |access-date=2023-01-20 |website=en.energinet.dk |language=en}}</ref><ref>{{Cite web |date=2022-07-18 |title=Managing wind volatility in Ireland with demand response |url=https://gridbeyond.com/managing-wind-volatility-in-ireland-with-demand-response/ |access-date=2023-01-20 |website=GridBeyond |language=en-US}}</ref> for example by remotely turning up water heater thermostats.<ref>{{Cite web |title=Demand Response – Analysis |url=https://www.iea.org/reports/demand-response |access-date=2023-01-20 |website=IEA |language=en-GB}}</ref>
=== Variability ===
{{Main|Variable renewable energy}} {{Further|Grid balancing}}
[[File: Toro de osborne.jpg|thumb|Wind turbines are typically installed in windy locations. In the image, wind power generators in Spain, near an Osborne bull.]] [[File:Roscoe Wind Farm in West Texas.jpg|thumb|right|Roscoe Wind Farm: an onshore wind farm in West Texas near Roscoe]]
Wind power is variable, and during low wind periods, it may need to be replaced by other power sources. Transmission networks presently cope with outages of other generation plants and daily changes in electrical demand, but the variability of intermittent power sources such as wind power is more frequent than those of conventional power generation plants which, when scheduled to be operating, may be able to deliver their nameplate capacity around 95% of the time.
Electric power generated from wind power can be highly variable at several different timescales: hourly, daily, or seasonally. Annual variation also exists but is not as significant.{{Citation needed|date=November 2021}} Because instantaneous electrical generation and consumption must remain in balance to maintain grid stability, this variability can present substantial challenges to incorporating large amounts of wind power into a grid system. Intermittency and the non-dispatchable nature of wind energy production can raise costs for regulation, incremental operating reserve, and (at high penetration levels) could require an increase in the already existing energy demand management, load shedding, storage solutions, or system interconnection with HVDC cables.
Fluctuations in load and allowance for the failure of large fossil-fuel generating units require operating reserve capacity, which can be increased to compensate for the variability of wind generation.
Utility-scale batteries are often used to balance hourly and shorter timescale variation,<ref>{{Cite web|last=Katz|first=Cheryl|title=The batteries that could make fossil fuels obsolete|url=https://www.bbc.com/future/article/20201217-renewable-power-the-worlds-largest-battery|access-date=2021-11-23|website=www.bbc.com|date=18 December 2020 |language=en|archive-date=11 January 2021|archive-url=https://web.archive.org/web/20210111075439/https://www.bbc.com/future/article/20201217-renewable-power-the-worlds-largest-battery|url-status=live}}</ref><ref>{{Cite web|date=2021-01-14|title=Report: An additional 20GWh of battery storage could significantly reduce wind power curtailment in UK|url=https://www.renewableenergyworld.com/storage/report-an-additional-20gwh-of-battery-storage-could-significantly-reduce-wind-power-curtailment-in-uk/|access-date=2021-11-23|website=Renewable Energy World|language=en-US|archive-date=26 February 2021|archive-url=https://web.archive.org/web/20210226223141/https://www.renewableenergyworld.com/storage/report-an-additional-20gwh-of-battery-storage-could-significantly-reduce-wind-power-curtailment-in-uk/|url-status=live}}</ref> but car batteries may gain ground from the mid-2020s.<ref>{{Cite web|title=Answers to the UK's wind energy storage issues are emerging – NS Energy|date=9 September 2021 |url=https://www.nsenergybusiness.com/features/wind-energy-storage-in-the-uk-is-posing-problems-but-long-term-solutions-are-emerging/|access-date=2021-11-23|language=en-US|archive-date=10 September 2021|archive-url=https://web.archive.org/web/20210910082016/https://www.nsenergybusiness.com/features/wind-energy-storage-in-the-uk-is-posing-problems-but-long-term-solutions-are-emerging/|url-status=live}}</ref> Wind power advocates argue that periods of low wind can be dealt with by simply restarting existing power stations that have been held in readiness, or interlinking with HVDC.<ref name="Czisch-Giebel">[http://www.risoe.dk/rispubl/reports/ris-r-1608_186-195.pdf Realisable Scenarios for a Future Electricity Supply based 100% on Renewable Energies] {{webarchive|url=https://web.archive.org/web/20140701230913/http://www.risoe.dk/rispubl/reports/ris-r-1608_186-195.pdf |date=1 July 2014}} Gregor Czisch, University of Kassel, Germany and Gregor Giebel, Risø National Laboratory, Technical University of Denmark</ref>
The combination of diversifying variable renewables by type and location, forecasting their variation, and integrating them with dispatchable renewables, flexible fueled generators, and demand response can create a power system that has the potential to meet power supply needs reliably. Integrating ever-higher levels of renewables is being demonstrated in the real world.<ref>{{Cite web |title=Annual variable renewable energy share and corresponding system integration phase in selected countries/regions, 2018 – Charts – Data & Statistics |url=https://www.iea.org/data-and-statistics/charts/annual-variable-renewable-energy-share-and-corresponding-system-integration-phase-in-selected-countries-regions-2018 |access-date=2023-01-20 |website=IEA |language=en-GB}}</ref>
thumb|Seasonal cycle of capacity factors for wind and photovoltaics in Europe under idealized assumptions. The figure illustrates the balancing effects of wind and solar energy at the seasonal scale (Kaspar et al., 2019).<ref name="balancing-europe" /> Solar power tends to be complementary to wind.<ref name=windsun>Wood, Shelby (21 January 2008) [http://blog.oregonlive.com/pdxgreen/2008/01/wind_sun_join_forces_at_washin.html Wind + sun join forces at Washington power plant] {{Webarchive|url=https://web.archive.org/web/20120118135025/http://blog.oregonlive.com/pdxgreen/2008/01/wind_sun_join_forces_at_washin.html |date=18 January 2012 }}. ''The Oregonian''.</ref><ref name=smallWindSystems>{{cite web |url=http://www.seco.cpa.state.tx.us/re/wind/smallwind.php |title=Small Wind Systems |publisher=Seco.cpa.state.tx.us |access-date=29 August 2010 |archive-url=https://web.archive.org/web/20121023190904/http://www.seco.cpa.state.tx.us/re/wind/smallwind.php |archive-date=23 October 2012 }}</ref> On daily to weekly timescales, high-pressure areas tend to bring clear skies and low surface winds, whereas low-pressure areas tend to be windier and cloudier. On seasonal timescales, solar energy peaks in summer, whereas in many areas wind energy is lower in summer and higher in winter.{{efn-ua|1=California is an exception}}<ref name="cleveland_water_crib">{{cite web |url = http://www.development.cuyahogacounty.us/pdf_development/en-US/ExeSum_WindResrc_CleveWtrCribMntr_Reprt.pdf |title = Lake Erie Wind Resource Report, Cleveland Water Crib Monitoring Site, Two-Year Report Executive Summary |publisher = Green Energy Ohio |date = 10 January 2008 |access-date = 27 November 2008 |archive-url = https://web.archive.org/web/20081217063550/http://www.development.cuyahogacounty.us/pdf_development/en-US/ExeSum_WindResrc_CleveWtrCribMntr_Reprt.pdf |archive-date = 17 December 2008 }} This study measured up to four times as much average wind power during winter as in summer for the test site.</ref> Thus the seasonal variation of wind and solar power tend to cancel each other somewhat.<ref name="balancing-europe">Kaspar, F., Borsche, M., Pfeifroth, U., Trentmann, J., Drücke, J., and Becker, P.: A climatological assessment of balancing effects and shortfall risks of photovoltaics and wind energy in Germany and Europe, Adv. Sci. Res., 16, 119–128, https://doi.org/10.5194/asr-16-119-2019 {{Webarchive|url=https://web.archive.org/web/20211124094345/https://asr.copernicus.org/articles/16/119/2019/ |date=24 November 2021 }}, 2019</ref> Wind hybrid power systems are becoming more popular.<ref>{{Cite web|date=2021-11-23|title=Turkish Cengiz evaluates expansion of its giant hybrid power plant|url=https://balkangreenenergynews.com/turkish-cengiz-evaluates-expansion-of-its-giant-hybrid-power-plant/|access-date=2021-11-24|website=Balkan Green Energy News|language=en-US}}</ref>
===Predictability=== {{Main|Wind power forecasting}} For any particular generator, there is an 80% chance that wind output will change less than 10% in an hour and a 40% chance that it will change 10% or more in 5 hours.<ref>{{cite web |url=http://www.nrel.gov/wind/systemsintegration/system_integration_basics.html |title=Wind Systems Integration Basics |archive-url=https://web.archive.org/web/20120607000124/http://www.nrel.gov/wind/systemsintegration/system_integration_basics.html |archive-date=7 June 2012}}</ref>
In summer 2021, wind power in the United Kingdom fell due to the lowest winds in seventy years,<ref>{{Cite web|last=Stevens|first=Pippa|date=2021-09-29|title=UK energy titan SSE says low wind, driest conditions in 70 years hit renewable generation|url=https://www.cnbc.com/2021/09/29/sse-says-low-wind-dry-conditions-hit-renewable-energy-generation.html|access-date=2021-11-23|website=CNBC|language=en|archive-date=11 November 2021|archive-url=https://web.archive.org/web/20211111110700/https://www.cnbc.com/2021/09/29/sse-says-low-wind-dry-conditions-hit-renewable-energy-generation.html|url-status=live}}</ref> In the future, smoothing peaks by producing green hydrogen may help when wind has a larger share of generation.<ref>{{Cite web|title='UK's largest electrolyser' could fuel hundreds of bus journeys with wind power each day|url=https://www.imeche.org/news/news-article/uk-s-largest-electrolyser-could-fuel-hundreds-of-bus-journeys-with-wind-power-each-day|access-date=2021-11-23|website=www.imeche.org|archive-date=22 November 2021|archive-url=https://web.archive.org/web/20211122212128/https://www.imeche.org/news/news-article/uk-s-largest-electrolyser-could-fuel-hundreds-of-bus-journeys-with-wind-power-each-day|url-status=live}}</ref>
While the output from a single turbine can vary greatly and rapidly as local wind speeds vary, as more turbines are connected over larger and larger areas the average power output becomes less variable and more predictable.<ref name="huang" /><ref>{{cite web |url=http://www.uwig.org/IEA_Report_on_variability.pdf |title=Variability of Wind Power and other Renewables: Management Options and Strategies |publisher=IEA |year=2005 |archive-url=https://web.archive.org/web/20051230204247/http://www.uwig.org/IEA_Report_on_variability.pdf |archive-date=30 December 2005}}</ref> Weather forecasting permits the electric-power network to be readied for the predictable variations in production that occur.<ref>{{Cite journal|last1=Santhosh|first1=Madasthu|last2=Venkaiah|first2=Chintham|last3=Kumar|first3=D. M. Vinod|date=2020|title=Current advances and approaches in wind speed and wind power forecasting for improved renewable energy integration: A review|journal=Engineering Reports|language=en|volume=2|issue=6|article-number=e12178|doi=10.1002/eng2.12178|issn=2577-8196|doi-access=free}}</ref>
It is thought that the most reliable low-carbon electricity systems will include a large share of wind power.<ref>{{Cite journal |last1=Tong |first1=Dan |last2=Farnham |first2=David J. |last3=Duan |first3=Lei |last4=Zhang |first4=Qiang |last5=Lewis |first5=Nathan S. |last6=Caldeira |first6=Ken |last7=Davis |first7=Steven J. |date=2021-10-22 |title=Geophysical constraints on the reliability of solar and wind power worldwide |journal=Nature Communications |language=en |volume=12 |issue=1 |page=6146 |doi=10.1038/s41467-021-26355-z |pmid=34686663 |pmc=8536784 |bibcode=2021NatCo..12.6146T |issn=2041-1723}}</ref>
===Energy storage=== {{main|Grid energy storage}} {{see also|List of energy storage projects}} thumb| Energy from wind, sunlight or other renewable energy is converted to potential energy for storage in devices such as electric batteries or higher-elevation water reservoirs. The stored potential energy is later converted to electricity that is added to the power grid, even when the original energy source is not available. Typically, conventional hydroelectricity complements wind power very well. When the wind is blowing strongly, nearby hydroelectric stations can temporarily hold back their water. When the wind drops they can, provided they have the generation capacity, rapidly increase production to compensate. This gives a very even overall power supply and virtually no loss of energy and uses no more water.
Alternatively, where a suitable head of water is not available, pumped-storage hydroelectricity or other forms of grid energy storage such as compressed air energy storage and thermal energy storage can store energy developed by high-wind periods and release it when needed. The type of storage needed depends on the wind penetration level – low penetration requires daily storage, and high penetration requires both short- and long-term storage – as long as a month or more.{{Citation needed|date=November 2021}} Stored energy increases the economic value of wind energy since it can be shifted to displace higher-cost generation during peak demand periods. The potential revenue from this arbitrage can offset the cost and losses of storage. Although pumped-storage power systems are only about 75% efficient and have high installation costs, their low running costs and ability to reduce the required electrical base-load can save both fuel and total electrical generation costs.<ref name=dinorwig>{{cite web|url=http://www.thegreenage.co.uk/greencommercial/hydroelectric-power/dinorwig-hydroelectric-plant |title=Dinorwig Hydroelectric Plant, Wales |publisher=Thegreenage.co.uk |access-date=11 January 2013 |archive-url=https://web.archive.org/web/20130111224833/http://www.thegreenage.co.uk/greencommercial/hydroelectric-power/dinorwig-hydroelectric-plant |archive-date=11 January 2013}}</ref><ref name=futureStorage>The Future of Electrical Energy Storage: The economics and potential of new technologies 2 January 2009 ID RET2107622</ref>
=== Energy payback ===
The energy needed to build a wind farm divided into the total output over its life, Energy Return on Energy Invested, of wind power varies, but averages about 20–25.<ref>[https://web.archive.org/web/20160409063616/http://www.eoearth.org/view/article/152560/ Energy return on investment (EROI) for wind energy]. The Encyclopedia of Earth (7 June 2007)</ref><ref>{{cite journal|doi=10.1504/IJSM.2014.062496 |title=Comparative life cycle assessment of 2.0 MW wind turbines |journal=International Journal of Sustainable Manufacturing |volume=3 |issue=2 |page=170 |year=2014 |last1=Haapala |first1=Karl R. |last2=Prempreeda |first2=Preedanood}}</ref> Thus, the energy payback time is typically around a year.
==Economics== thumb|upright=1.4|Onshore wind cost per kilowatt-hour between 1983 and 2017<ref>{{cite web |title=Onshore wind cost per kilowatt-hour |url=https://ourworldindata.org/grapher/onshore-wind-lcoe |website=Our World in Data |access-date=18 October 2020 |archive-date=19 November 2020 |archive-url=https://web.archive.org/web/20201119175742/https://ourworldindata.org/grapher/onshore-wind-lcoe |url-status=live }}</ref> Onshore wind is an inexpensive source of electric power, cheaper than coal plants and new gas plants.<ref name=":6" /> According to BusinessGreen, wind turbines reached grid parity (the point at which the cost of wind power matches traditional sources) in some areas of Europe in the mid-2000s, and in the US around the same time. Falling prices continue to drive the Levelized cost down and it has been suggested that it has reached general grid parity in Europe in 2010, and will reach the same point in the US around 2016 due to an expected reduction in capital costs of about 12%.<ref name="businessgreen">[http://www.businessgreen.com/bg/news/2124487/onshore-wind-reach-grid-parity-2016 "Onshore wind to reach grid parity by 2016"] {{Webarchive|url=https://web.archive.org/web/20120117080111/http://www.businessgreen.com/bg/news/2124487/onshore-wind-reach-grid-parity-2016 |date=17 January 2012 }}, BusinessGreen, 14 November 2011</ref>{{Update inline|date=September 2022}} In 2021, the CEO of Siemens Gamesa warned that increased demand for low-cost wind turbines combined with high input costs and high costs of steel result in increased pressure on the manufacturers and decreasing profit margins.<ref>{{Cite news|title=World's largest offshore wind turbine maker warns of price pressures|url=https://www.ft.com/content/49d77f86-2a85-414e-b879-b4c00a51887f|url-status=live|access-date=2021-06-16|newspaper=Financial Times|date=16 March 2021 |archive-date=24 June 2021|archive-url=https://web.archive.org/web/20210624200237/https://www.ft.com/content/49d77f86-2a85-414e-b879-b4c00a51887f}}</ref>
Northern Eurasia, Canada, some parts of the United States, and Patagonia in Argentina are the best areas for onshore wind: whereas in other parts of the world solar power, or a combination of wind and solar, tend to be cheaper.<ref>{{Cite journal |last1=Bogdanov |first1=Dmitrii |last2=Ram |first2=Manish |last3=Aghahosseini |first3=Arman |last4=Gulagi |first4=Ashish |last5=Oyewo |first5=Ayobami Solomon |last6=Child |first6=Michael |last7=Caldera |first7=Upeksha |last8=Sadovskaia |first8=Kristina |last9=Farfan |first9=Javier |last10=De Souza Noel Simas Barbosa |first10=Larissa |last11=Fasihi |first11=Mahdi |date=2021-07-15 |title=Low-cost renewable electricity as the key driver of the global energy transition towards sustainability |journal=Energy |language=en |volume=227 |article-number=120467 |doi=10.1016/j.energy.2021.120467 |s2cid=233706454 |issn=0360-5442|doi-access=free |bibcode=2021Ene...22720467B }}</ref>{{Rp|page=8}}
===Electric power cost and trends=== [[File: Turbine Blade Convoy Passing through Edenfield.jpg|thumb|A turbine blade convoy passing through Edenfield in the U.K. (2008). Even longer 2-piece blades are now manufactured, and then assembled on-site to reduce difficulties in transportation.]] {{See also|Cost of electricity by source}} Wind power is capital intensive but has no fuel costs.<ref name="IRENA">Dolf Gielen. "[https://web.archive.org/web/20140423214203/http://www.irena.org/DocumentDownloads/Publications/RE_Technologies_Cost_Analysis-WIND_POWER.pdf Renewable Energy Technologies: Cost Analysis Series: Wind Power]" ''International Renewable Energy Agency'', June 2012. Quote: "wind is capital intensive, but has no fuel costs"</ref> The price of wind power is therefore much more stable than the volatile prices of fossil fuel sources.<ref>[http://www.nationalgridus.com/non_html/c3-3_NG_wind_policy.pdf Transmission and Wind Energy: Capturing the Prevailing Winds for the Benefit of Customers] {{Webarchive|url=https://web.archive.org/web/20140423231722/http://www.nationalgridus.com/non_html/c3-3_NG_wind_policy.pdf |date=23 April 2014}}. National Grid US (September 2006).</ref> However, the estimated average cost per unit of electric power must incorporate the cost of construction of the turbine and transmission facilities, borrowed funds, return to investors (including the cost of risk), estimated annual production, and other components, averaged over the projected useful life of the equipment, which may be more than 20 years. Energy cost estimates are highly dependent on these assumptions so published cost figures can differ substantially.
The presence of wind energy, even when subsidized, can reduce costs for consumers (€5 billion/yr in Germany) by reducing the marginal price and by minimizing the use of expensive peaking power plants.<ref>{{cite book |last=Rao |first=K.R |date=October 17, 2019 |title=Wind Energy for Power Generation: Meeting the Challenge of Practical Implementation |url=https://books.google.com/books?id=bY23DwAAQBAJ&q=he+presence+of+wind+energy%2C+even+when+subsidized%2C+can+reduce+costs+for+consumers+%28%E2%82%AC5+billion%2Fyr+in+Germany%29+by+reducing+the+marginal+price%2C+by+minimizing+the+use+of+expensive+peaking+power+plants.&pg=PA586 |url-status=live |location= |publisher=Springer Nature, 2019 |isbn=978-3-319-75134-4 |archive-url=https://web.archive.org/web/20211124094409/https://books.google.com/books?id=bY23DwAAQBAJ&q=he+presence+of+wind+energy%2C+even+when+subsidized%2C+can+reduce+costs+for+consumers+%28%E2%82%AC5+billion%2Fyr+in+Germany%29+by+reducing+the+marginal+price%2C+by+minimizing+the+use+of+expensive+peaking+power+plants.&pg=PA586 |archive-date=24 November 2021 |access-date=4 May 2021 }}</ref>
The cost has decreased as wind turbine technology has improved. There are now longer and lighter wind turbine blades, improvements in turbine performance, and increased power generation efficiency. Also, wind project capital expenditure costs and maintenance costs have continued to decline.<ref>{{cite web |url=https://obamawhitehouse.archives.gov/blog/2012/08/14/banner-year-us-wind-industry |title=A Banner Year for the U.S. Wind Industry |author=Danielson, David |via=National Archives |work=whitehouse.gov |date=14 August 2012 |access-date=1 March 2021 |archive-date=10 March 2021 |archive-url=https://web.archive.org/web/20210310021408/https://obamawhitehouse.archives.gov/blog/2012/08/14/banner-year-us-wind-industry |url-status=live }}</ref>
In 2021, a Lazard study of unsubsidized electricity said that wind power levelized cost of electricity continues to fall but more slowly than before. The study estimated new wind-generated electricity cost from $26 to $50/MWh, compared to new gas power from $45 to $74/MWh. The median cost of fully deprecated existing coal power was $42/MWh, nuclear $29/MWh and gas $24/MWh. The study estimated offshore wind at around $83/MWh. Compound annual growth rate was 4% per year from 2016 to 2021, compared to 10% per year from 2009 to 2021.<ref name=":6">{{Cite web|title=Levelized Cost Of Energy, Levelized Cost Of Storage, and Levelized Cost Of Hydrogen|url=http://www.lazard.com/perspective/levelized-cost-of-energy-levelized-cost-of-storage-and-levelized-cost-of-hydrogen/|access-date=2021-11-24|website=Lazard.com|language=en}}</ref>
===The value of wind power=== While the levelised costs of wind power may have reached that of traditional combustion based power technologies, the market value of the generated power is also lower due to the merit order effect, which implies that electricity market prices are lower in hours with substantial generation of variable renewable energy due to the low marginal costs of this technology.<ref>{{cite journal | first1=Lion |last1= Hirth| title=The market value of variable renewables: The effect of solar wind power variability on their relative price|journal=Energy Economics|volume=38 |year=2013|pages= 218–236|issn= 0140-9883| doi= 10.1016/j.eneco.2013.02.004 |bibcode= 2013EneEc..38..218H|url= https://nbn-resolving.org/urn:nbn:de:kobv:b1570-opus4-22900|hdl=1814/27135|hdl-access=free}} </ref> The effect has been identified in several European markets.<ref>{{ cite journal |first1 =Marijke| last1=Welisch |first2=André |last2=Ortner| first3=Gustav |last3=Resch | title =Assessment of RES technology market values and the merit-order effect – an econometric multi-country analysis|journal = Energy & Environment| volume = 27| number = 1| pages = 105–121| year =2016| doi = 10.1177/0958305X16638574 | bibcode=2016EnEnv..27..105W }}</ref> For wind power plants exposed to electricity market pricing in markets with high penetration of variable renewable energy sources, profitability can be challenged.
===Incentives and community benefits=== Turbine prices have fallen significantly in recent years due to tougher competitive conditions such as the increased use of energy auctions, and the elimination of subsidies in many markets.<ref>{{cite web|author=Reed, Stanley|date=9 November 2017|title=As Wind Power Sector Grows, Turbine Makers Feel the Squeeze|url=https://mobile.nytimes.com/2017/11/09/business/energy-environment/wind-turbine-vestas.html|url-status=live|archive-url=https://web.archive.org/web/20171111152417/https://mobile.nytimes.com/2017/11/09/business/energy-environment/wind-turbine-vestas.html|archive-date=11 November 2017|access-date=11 November 2017|publisher=TNT}}</ref> As of 2021, subsidies are still often given to offshore wind. However, they are generally no longer necessary for onshore wind in countries with even a very low carbon price such as China, provided there are no competing fossil fuel subsidies.<ref>{{Cite web|title=China's 2022 Wind Power Growth to Stay Strong Despite Subsidy End|url=https://www.fitchratings.com/research/corporate-finance/china-2022-wind-power-growth-to-stay-strong-despite-subsidy-end-23-11-2021 |access-date=2021-11-24|website=www.fitchratings.com}}</ref>
Secondary market forces provide incentives for businesses to use wind-generated power, even if there is a premium price for the electricity. For example, socially responsible manufacturers pay utility companies a premium that goes to subsidize and build new wind power infrastructure. Companies use wind-generated power, and in return, they can claim that they are undertaking strong "green" efforts.<ref name="green-e">[https://speakerdeck.com/resourcesolutions/the-2010-green-e-verification-report The 2010 Green-e Verification Report] {{Webarchive|url=https://web.archive.org/web/20130611235247/https://speakerdeck.com/resourcesolutions/the-2010-green-e-verification-report |date=11 June 2013 }} Retrieved on 20 May 2009</ref> Wind projects provide local taxes, or payments in place of taxes and strengthen the economy of rural communities by providing income to farmers with wind turbines on their land.<ref name="nine">American Wind Energy Association (2009) [http://www.slideshare.net/Calion/awea-annual-wind-report-2009 Annual Wind Industry Report, Year Ending 2008] {{Webarchive|url=https://web.archive.org/web/20130113205504/http://www.slideshare.net/Calion/awea-annual-wind-report-2009|date=13 January 2013}} p. 11</ref><ref>{{cite web|date=1 August 2011|title=Direct Federal Financial Interventions and Subsidies in Energy in Fiscal Year 2010|url=http://www.eia.gov/analysis/requests/subsidy/|url-status=live|archive-url=https://web.archive.org/web/20191001012707/https://www.eia.gov/analysis/requests/subsidy/|archive-date=1 October 2019|access-date=29 April 2012|website=Report|publisher=Energy Information Administration}}</ref>
The wind energy sector can also produce jobs during the construction and operating phase.<ref>{{cite web | url=https://windexchange.energy.gov/projects/economic-impacts | title=WINDExchange: Wind Energy's Economic Impacts to Communities }}</ref> Jobs include the manufacturing of wind turbines and the construction process, which includes transporting, installing, and then maintaining the turbines.
==Small-scale wind power== {{main|Small wind turbine}} {{Further|Microgeneration (energy)}} [[File:Quietrevolution Bristol 3513051949.jpg|thumb|A small Quietrevolution QR5 Gorlov type vertical axis wind turbine on the roof of Bristol Beacon in Bristol, England. Measuring 3 m in diameter and 5 m high, it has a nameplate rating of 6.5 kW.]] Small-scale wind power is the name given to wind generation systems with the capacity to produce up to 50 kW of electrical power.<ref name="smallScaleCarbonTrust">{{cite web |url=http://www.carbontrust.com/resources/reports/technology/small-scale-wind-energy |title=Small-scale wind energy |publisher=Carbontrust.co.uk |access-date=29 August 2010 |archive-date=14 May 2013 |archive-url=https://web.archive.org/web/20130514062058/http://www.carbontrust.com/resources/reports/technology/small-scale-wind-energy |url-status=live }}</ref> Isolated communities, that may otherwise rely on diesel generators, may use wind turbines as an alternative. Individuals may purchase these systems to reduce or eliminate their dependence on grid electric power for economic reasons, or to reduce their carbon footprint. Wind turbines have been used for household electric power generation in conjunction with battery storage over many decades in remote areas.<ref>{{cite web | url = http://telosnet.com/wind/20th.html | title = Part 2 – 20th Century Developments | last = Dodge | first = Darrell M. | website = Illustrated history of wind power development | publisher = TelosNet Web Development | access-date = 27 April 2012 | archive-date = 28 March 2012 | archive-url = https://web.archive.org/web/20120328083701/http://telosnet.com/wind/20th.html | url-status = usurped }}</ref>
Examples of small-scale wind power projects in an urban setting can be found in New York City, where, since 2009, several building projects have capped their roofs with Gorlov-type helical wind turbines. Although the energy they generate is small compared to the buildings' overall consumption, they help to reinforce the building's 'green' credentials in ways that "showing people your high-tech boiler" cannot, with some of the projects also receiving the direct support of the New York State Energy Research and Development Authority.<ref>Chanban, Matt A.V.; Delaquérière, Alain. [https://www.nytimes.com/2014/05/27/nyregion/turbines-pop-up-on-new-york-roofs-along-with-questions-of-efficiency.html?ref=earth&gwh=7741044F383A0294E75C6B34AA88E68D Turbines Popping Up on New York Roofs, Along With Questions of Efficiency] {{Webarchive|url=https://web.archive.org/web/20170709122333/https://www.nytimes.com/2014/05/27/nyregion/turbines-pop-up-on-new-york-roofs-along-with-questions-of-efficiency.html?ref=earth&gwh=7741044F383A0294E75C6B34AA88E68D |date=9 July 2017 }}, ''The New York Times'' website, 26 May 2014, and in print on 27 May 2014, p. A19 of the New York edition.</ref>
Grid-connected domestic wind turbines may use grid energy storage, thus replacing purchased electric power with locally produced power when available. The surplus power produced by domestic microgenerators can, in some jurisdictions, be fed into the network and sold to the utility company, producing a retail credit for the microgenerators' owners to offset their energy costs.<ref name="home-made">[http://www.thesundaytimes.co.uk/sto/Migration/article100906.ece Home-made energy to prop up grid] {{Webarchive|url=https://web.archive.org/web/20140818194835/http://www.thesundaytimes.co.uk/sto/Migration/article100906.ece |date=18 August 2014 }} The Times 22 June 2008 Retrieved on 10 January 2013</ref>
Off-grid system users can either adapt to intermittent power or use batteries, photovoltaic, or diesel systems to supplement the wind turbine.<ref>{{Cite journal|last1=Ramirez Camargo|first1=Luis|last2=Nitsch|first2=Felix|last3=Gruber|first3=Katharina|last4=Valdes|first4=Javier|last5=Wuth|first5=Jane|last6=Dorner|first6=Wolfgang|date=January 2019|title=Potential Analysis of Hybrid Renewable Energy Systems for Self-Sufficient Residential Use in Germany and the Czech Republic|journal=Energies|language=en|volume=12|issue=21|page=4185|doi=10.3390/en12214185|doi-access=free |bibcode=2019Energ..12.4185R }}</ref> Equipment such as parking meters, traffic warning signs, street lighting, or wireless Internet gateways may be powered by a small wind turbine, possibly combined with a photovoltaic system, that charges a small battery replacing the need for a connection to the power grid.<ref>{{cite web | url=http://cleantechnica.com/2009/05/13/exploiting-the-downsides-of-wind-and-solar/ | title=Wind, Solar-Powered Street Lights Only Need a Charge Once Every Four Days | last=Kart | first=Jeff | date=13 May 2009 | website=Clean Technica | access-date=30 April 2012 | archive-date=17 November 2011 | archive-url=https://web.archive.org/web/20111117075022/http://cleantechnica.com/2009/05/13/exploiting-the-downsides-of-wind-and-solar/ | url-status=live }}</ref>
Airborne wind turbines, such as kites, can be used in places at risk of hurricanes, as they can be taken down in advance.<ref>{{Cite web |last=Jones |first=Nicola |title=The kites seeking the world's surest winds |url=https://www.bbc.com/future/article/20220309-the-kites-flying-to-harness-the-worlds-strongest-winds |access-date=2022-04-02 |website=www.bbc.com |date=10 March 2022 |language=en}}</ref>
== Impact on environment and landscape == {{Excerpt|Environmental impact of wind power}}
== Politics ==
=== Central government ===
Although wind turbines with fixed bases are a mature technology and new installations are generally no longer subsidized,<ref>{{Cite web |last=Buljan |first=Adrijana |date=2022-11-11 |title=RWE Wins Dutch Subsidy-Free Offshore Wind Tender with 760 MW Project Including Green Hydrogen and Floating Solar |url=https://www.offshorewind.biz/2022/11/11/rwe-wins-dutch-subsidy-free-offshore-wind-tender-with-760-mw-project-including-green-hydrogen-and-floating-solar/ |access-date=2022-12-04 |website=Offshore Wind |language=en-US}}</ref><ref>{{Cite web |title=Chinese Offshore Wind Capacity Boom Driven By State Subsidies |url=https://www.rigzone.com/news/chinese_offshore_wind_capacity_boom_driven_by_state_subsidies-23-nov-2022-171136-article/ |access-date=2022-12-04 |website=www.rigzone.com |language=en |quote=A key driver of the rush to add capacity was the termination of central government subsidies at the end of 2021.}}</ref> floating wind turbines are a relatively new technology so some governments subsidize them, for example to use deeper waters.<ref>{{Cite web |title=Floating wind could be the key to clean energy transition |url=https://www.weforum.org/agenda/2021/07/floating-wind-float-like-a-wind-turbine-on-the-high-sea/ |access-date=2022-12-04 |website=World Economic Forum |date=27 July 2021 |language=en}}</ref>
Fossil fuel subsidies by some governments are slowing the growth of renewables.<ref>{{Cite journal |last=Timperley |first=Jocelyn |date=2021-10-20 |title=Why fossil fuel subsidies are so hard to kill |journal=Nature |language=en |volume=598 |issue=7881 |pages=403–405 |doi=10.1038/d41586-021-02847-2 |pmid=34671143 |bibcode=2021Natur.598..403T |s2cid=239052649 |quote=Fossil-fuel subsidies are one of the biggest financial barriers hampering the world's shift to renewable energy sources.|doi-access=free }}</ref>
Permitting of wind farms can take years and some governments are trying to speed up – the wind industry says this will help limit climate change and increase energy security<ref>{{Cite web |title=Explainer: What is offshore wind and what does its future look like? |url=https://www.weforum.org/agenda/2022/11/offshore-wind-farms-future-renewables/ |access-date=2022-12-04 |website=World Economic Forum |date=22 November 2022 |language=en}}</ref> – sometimes groups such as fishers resist this<ref>{{Cite web |last=Richards |first=Heather |date=2022-12-01 |title=Biden wants to launch 16 offshore wind farms. Can he? |url=https://www.eenews.net/articles/biden-wants-to-launch16-offshore-wind-farms-can-he/ |access-date=2022-12-04 |website=E&E News |language=en-US}}</ref> but governments say that rules protecting biodiversity will still be followed.<ref>{{Cite web |title=Europe takes emergency action to remove permitting bottlenecks for wind power {{!}} REVE News of the wind sector in Spain and in the world |url=https://www.evwind.es/2022/11/08/europe-takes-emergency-action-to-remove-permitting-bottlenecks-for-wind-power/88716 |access-date=2022-12-04 |website=www.evwind.es |date=8 November 2022 |language=en-US}}</ref>
=== Public opinion === thumb |Acceptance of wind and solar facilities in one's community is stronger among U.S. Democrats (blue), while acceptance of nuclear power plants is stronger among U.S. Republicans (red).<ref name=WashPost_20231003>{{cite news |last1=Chiu |first1=Allyson |last2=Guskin |first2=Emily |last3=Clement |first3=Scott |title=Americans don't hate living near solar and wind farms as much as you might think |url=https://www.washingtonpost.com/climate-solutions/2023/10/03/solar-panels-wind-turbines-nimby/ |newspaper=The Washington Post |date=3 October 2023 |archive-url=https://web.archive.org/web/20231003211732/https://www.washingtonpost.com/climate-solutions/2023/10/03/solar-panels-wind-turbines-nimby/ |archive-date=3 October 2023 | url-status=live }}</ref> Surveys of public attitudes across Europe and in many other countries show strong public support for wind power.<ref name="com" /><ref name="vipublic">{{cite web |url= http://www.ewea.org/fileadmin/ewea_documents/documents/publications/WD/WD22vi_public.pdf |title=A Summary of Opinion Surveys on Wind Power |access-date=17 January 2012 |archive-url=https://web.archive.org/web/20130502230544/http://www.ewea.org/fileadmin/ewea_documents/documents/publications/WD/WD22vi_public.pdf |archive-date=2 May 2013 }}</ref><ref name="eon">{{cite web | url=http://eon-uk.com/generation/publicattitudes.aspx |archive-url=https://web.archive.org/web/20120504073200/http://eon-uk.com/generation/publicattitudes.aspx |archive-date=4 May 2012 |title=Public attitudes to wind farms |publisher=Eon-uk.com |date=28 February 2008 |access-date=17 January 2012}}</ref> Bakker et al. (2012) found in their study that residents who did not want turbines built near them suffered significantly more stress than those who "benefited economically from wind turbines".<ref>{{Cite journal|last1=Bakker|first1=R.H.|last2=Pedersen|first2=E|date=2012|title=Impact of wind turbine sound on annoyance, self-reported sleep disturbance and psychological distress|journal=Science of the Total Environment|volume=425|pages=42–51|doi=10.1016/j.scitotenv.2012.03.005|pmid=22481052|bibcode=2012ScTEn.425...42B|hdl=11370/e2c2a869-d1b6-4c61-ac35-2df8596a2402|s2cid=6845478 |url=https://pure.rug.nl/ws/files/6778721/Bakker_2012_Sci_Total_Environm.pdf|hdl-access=free|access-date=14 December 2019|archive-date=18 February 2019|archive-url=https://web.archive.org/web/20190218065746/https://pure.rug.nl/ws/files/6778721/Bakker_2012_Sci_Total_Environm.pdf|url-status=live}}</ref>
Although wind power is a popular form of energy generation, onshore or near offshore wind farms are sometimes opposed for their impact on the landscape (especially scenic areas, heritage areas and archaeological landscapes), as well as noise, and impact on tourism.<ref>{{Cite web|date=2021-03-24|title=Opposition to wind farm plans because of negative impact on 'tourism'|url=https://nation.cymru/news/opposition-to-wind-farm-plans-because-of-negative-impact-on-tourism/|access-date=2021-11-16|website=Nation.Cymru|language=en-GB|archive-date=16 November 2021|archive-url=https://web.archive.org/web/20211116180821/https://nation.cymru/news/opposition-to-wind-farm-plans-because-of-negative-impact-on-tourism/|url-status=live}}</ref><ref>{{Cite news|last=Schultz|first=Norm|title=Wind Farm Opposition in the Great Lakes|url=https://www.tradeonlytoday.com/columns-blogs/wind-farm-opposition-in-the-great-lakes|access-date=2021-11-16|website=Trade Only Today|date=29 June 2021 |language=en-us|archive-date=16 November 2021|archive-url=https://web.archive.org/web/20211116180821/https://www.tradeonlytoday.com/columns-blogs/wind-farm-opposition-in-the-great-lakes|url-status=live}}</ref>
In other cases, there is direct community ownership of wind farms. The hundreds of thousands of people who have become involved in Germany's small and medium-sized wind farms demonstrate such support there.<ref>{{cite web |url=http://dsc.discovery.com/technology/my-take/community-wind-farm.html |title=Community Power Empowers |publisher=Dsc.discovery.com |date=26 May 2009 |access-date=17 January 2012 |archive-url=https://web.archive.org/web/20090325021002/http://dsc.discovery.com/technology/my-take/community-wind-farm.html |archive-date=25 March 2009 }}</ref>
A 2010 Harris Poll found strong support for wind power in Germany, other European countries, and the United States.<ref name="com" /><ref name="vipublic" /><ref>{{cite web|url=http://www.eon-uk.com/generation/publicattitudes.aspx |title=Public attitudes to wind farms |publisher=Eon-uk.com |date=28 February 2008 |access-date=17 January 2012 |archive-url=https://web.archive.org/web/20120314142558/http://www.eon-uk.com/generation/publicattitudes.aspx |archive-date=14 March 2012}}</ref>
Public support in the United States has decreased from 75% in 2020 to 62% in 2021, with the Democratic Party supporting the use of wind energy twice as much as the Republican Party.<ref>{{cite web | url=https://www.pewresearch.org/fact-tank/2021/06/08/most-americans-support-expanding-solar-and-wind-energy-but-republican-support-has-dropped/ | title=Most Americans support expanding solar and wind energy, but Republican support has dropped | date=8 June 2021 }}</ref> President Biden signed an executive order to begin building large scale wind farms.<ref>{{cite web | url=https://bidenwhitehouse.archives.gov/briefing-room/statements-releases/2021/03/29/fact-sheet-biden-administration-jumpstarts-offshore-wind-energy-projects-to-create-jobs/ | title=FACT SHEET: Biden Administration Jumpstarts Offshore Wind Energy Projects to Create Jobs | newspaper=The White House | date=29 March 2021 }}</ref>
In China, Shen et al. (2019) found that Chinese city-dwellers may be resistant to building wind turbines in urban areas, with a surprisingly high proportion of people citing an unfounded fear of radiation as driving their concerns.<ref>{{cite journal | last1 = Shen | first1 = Shiran Victoria | last2 = Cain | first2 = Bruce E. | last3 = Hui | first3 = Iris | title = Public receptivity in China towards wind energy generators: A survey experimental approach | journal = Energy Policy | volume = 129 | pages = 619–627 | doi=10.1016/j.enpol.2019.02.055| year = 2019| bibcode = 2019EnPol.129..619S | s2cid = 159387276 }}</ref> Also, the study finds that like their counterparts in OECD countries, urban Chinese respondents are sensitive to direct costs and wildlife externalities. Distributing relevant information about turbines to the public may alleviate resistance.
=== Community ===
{{See also|Community debate about wind farms}}
[[File:Wind tubines cumbria.JPG|thumb|upright=2.05|Wind turbines such as these, in Cumbria, England, have been opposed for a number of reasons, including aesthetics, by some sectors of the population.<ref>{{cite web |url=http://www.visitcumbria.com/wc/windfarms.htm |title=Wind Farms in Cumbria |access-date=3 October 2008 |archive-url=https://web.archive.org/web/20081210060920/http://www.visitcumbria.com/wc/windfarms.htm |archive-date=10 December 2008 }}</ref><ref>{{cite news | url=https://news.bbc.co.uk/2/hi/business/3661728.stm | title=Wind Turbulence over turbines in Cumbria | last=Arnold | first=James | work=BBC News | date=20 September 2004 | access-date=20 March 2012 | archive-date=17 May 2014 | archive-url=https://web.archive.org/web/20140517122315/http://news.bbc.co.uk/1/hi/business/3661728.stm | url-status=live }}</ref>]]
Many wind power companies work with local communities to reduce environmental and other concerns associated with particular wind farms.<ref>{{cite web |url=http://www.renewableenergyaccess.com/rea/news/story?id=48671 |title=Group Dedicates Opening of 200 MW Big Horn Wind Farm: Farm incorporates conservation efforts that protect wildlife habitat |publisher=Renewableenergyaccess.com |access-date=17 January 2012 |url-status=usurped |archive-url=https://web.archive.org/web/20071012192322/http://www.renewableenergyaccess.com/rea/news/story?id=48671 |archive-date=12 October 2007 }}</ref><ref>{{cite web | first=Jeanette | last=Fisher | date=2006 | url=http://environmentpsychology.com/wind_power_midamerican's_intrepid_wind_farm1.htm | title=Wind Power: MidAmerican's Intrepid Wind Farm | publisher=Environmentpsychology.com | access-date=20 March 2012 | archive-url=https://web.archive.org/web/20111102223323/http://environmentpsychology.com/wind_power_midamerican%27s_intrepid_wind_farm1.htm | archive-date=2 November 2011 }}</ref><ref>{{cite web | url=http://www.agl.com.au/environment/sustainability/Pages/StakeholderEngagement.aspx | archive-url=https://web.archive.org/web/20080721003610/http://www.agl.com.au/environment/sustainability/Pages/StakeholderEngagement.aspx |archive-date=21 July 2008 | title=Stakeholder Engagement | publisher=Agl.com.au | date=19 March 2008}}</ref> In other cases there is direct community ownership of wind farm projects. Appropriate government consultation, planning and approval procedures also help to minimize environmental risks.<ref name="com">{{cite web |url=http://www.ewea.org/fileadmin/ewea_documents/documents/press_releases/factsheet_environment2.pdf |publisher=Renewable Energy House |title=Wind Energy and the Environment |access-date=17 January 2012 |archive-url=https://web.archive.org/web/20130228202639/http://www.ewea.org/fileadmin/ewea_documents/documents/press_releases/factsheet_environment2.pdf |archive-date=28 February 2013 }}</ref><ref>{{cite web|url=http://www.environment.gov.au/settlements/renewable/publications/pubs/wind-discussionpaper.pdf |title=National Code for Wind Farms |publisher=Environment.gov.au |access-date=17 January 2012 |archive-url=https://web.archive.org/web/20080905112322/http://www.environment.gov.au/settlements/renewable/publications/pubs/wind-discussionpaper.pdf |archive-date=5 September 2008}}</ref><ref>{{cite web |url=http://www.publish.csiro.au/?act=view_file&file_id=EC140p6a.pdf |title=New standard and big investment for wind energy |publisher=Publish.csiro.au |date=17 December 2007 |access-date=20 March 2012 |archive-date=18 September 2008 |archive-url=https://web.archive.org/web/20080918231046/http://www.publish.csiro.au/?act=view_file&file_id=EC140p6a.pdf |url-status=live }}</ref> Some may still object to wind farms<ref name="wind-watch.org" /> but many say their concerns should be weighed against the need to address the threats posed by air pollution,<ref>{{Cite news |title=Misinformation is derailing renewable energy projects across the United States |language=en |work=NPR.org |url=https://www.npr.org/2022/03/28/1086790531/renewable-energy-projects-wind-energy-solar-energy-climate-change-misinformation |access-date=2022-09-27}}</ref><ref name=":9">{{Cite web |title=How Wind Energy Can Help Us Breathe Easier |url=https://www.energy.gov/eere/wind/articles/how-wind-energy-can-help-us-breathe-easier |access-date=2022-09-27 |website=Energy.gov |language=en}}</ref> climate change<ref>{{Cite web |title=Advantages and Challenges of Wind Energy |url=https://www.energy.gov/eere/wind/advantages-and-challenges-wind-energy |access-date=2022-09-27 |website=Energy.gov |language=en}}</ref> and the opinions of the broader community.<ref>The Australia Institute (October 2006) [http://www.tai.org.au/documents/dp_fulltext/DP91.pdf Wind Farms: The facts and the fallacies] {{Webarchive|url=https://web.archive.org/web/20120225091609/http://www.tai.org.au/documents/dp_fulltext/DP91.pdf |date=25 February 2012}} Discussion Paper No. 91, {{ISSN|1322-5421}}, p. 28.</ref>
In the US, wind power projects are reported to boost local tax bases, helping to pay for schools, roads, and hospitals, and to revitalize the economies of rural communities by providing steady income to farmers and other landowners.<ref name="nine" />
In the UK, both the National Trust and the Campaign to Protect Rural England have expressed concerns about the effects on the rural landscape caused by inappropriately sited wind turbines and wind farms.<ref>[https://www.bbc.co.uk/news/uk-england-northamptonshire-17367028 "Wind farm to be built near a Northamptonshire heritage site"] {{Webarchive|url=https://web.archive.org/web/20180926231807/https://www.bbc.co.uk/news/uk-england-northamptonshire-17367028 |date=26 September 2018 }}, ''BBC News'', 14 March 2012. Retrieved 20 March 2012.</ref><ref>{{cite web | url = http://www.edp24.co.uk/news/environment/cpre_calls_for_action_over_proliferation_of_wind_turbines_1_1363291 | title = CPRE calls for action over 'proliferation' of wind turbines | last = Hill | first = Chris | date = 30 April 2012 | website = EDP 24 | publisher = Archant community Media Ltd | access-date = 30 April 2012 | archive-date = 1 May 2012 | archive-url = https://web.archive.org/web/20120501102807/http://www.edp24.co.uk/news/environment/cpre_calls_for_action_over_proliferation_of_wind_turbines_1_1363291 | url-status = live }}</ref>
[[File: Whitelee panorama.JPG|thumb|upright=2.05|right|A panoramic view of the United Kingdom's Whitelee Wind Farm with Lochgoin Reservoir in the foreground.]] Some wind farms have become tourist attractions. The Whitelee Wind Farm Visitor Centre has an exhibition room, a learning hub, a café with a viewing deck and also a shop. It is run by the Glasgow Science Centre.<ref>{{cite web |url = http://www.whiteleewindfarm.co.uk/visitor_centre |title = Whitelee Windfarm |website = Scottish Power Renewables |archive-url = https://web.archive.org/web/20120302104242/http://www.whiteleewindfarm.co.uk/visitor_centre |archive-date = 2 March 2012 }}</ref>
In Denmark, a loss-of-value scheme gives people the right to claim compensation for loss of value of their property if it is caused by proximity to a wind turbine. The loss must be at least 1% of the property's value.<ref name="Danish-loss-of-value-scheme">{{cite book | url=http://www.ens.dk/sites/ens.dk/files/supply/renewable-energy/wind-power/Vindturbines%20in%20DK%20eng.pdf | title=Wind Turbines in Denmark | publisher=section 6.8, p. 22, Danish Energy Agency | date=November 2009 | isbn=978-87-7844-821-7 | archive-url=https://web.archive.org/web/20131023055825/http://www.ens.dk/sites/ens.dk/files/supply/renewable-energy/wind-power/Vindturbines%20in%20DK%20eng.pdf | archive-date=23 October 2013 }}</ref>
Despite this general support for the concept of wind power in the public at large, local opposition often exists and has delayed or aborted a number of projects.<ref>{{cite journal | url=http://www.shef.ac.uk/polopoly_fs/1.88117!/file/Understanding-wind-farm-opposition---Dr-Chris-Jones-PDF-674K-.pdf | title=Understanding 'local' opposition to wind development in the UK How big is a backyard? | doi=10.1016/j.enpol.2010.01.051 | year=2010 | last1=Jones | first1=Christopher R. | last2=Richard Eiser | first2=J. | journal=Energy Policy | volume=38 | issue=6 | page=3106 | bibcode=2010EnPol..38.3106J | access-date=14 January 2013 | archive-date=24 January 2013 | archive-url=https://web.archive.org/web/20130124105605/http://www.shef.ac.uk/polopoly_fs/1.88117!/file/Understanding-wind-farm-opposition---Dr-Chris-Jones-PDF-674K-.pdf | url-status=live }}</ref><ref>[http://www.wind-works.org/articles/tilting.html Tilting at Windmills: Public Opinion Toward Wind Energy] {{Webarchive|url=https://web.archive.org/web/20130118101946/http://www.wind-works.org/articles/tilting.html |date=18 January 2013 }}. Wind-works.org. Retrieved on 1 October 2013.</ref><ref>Yates, Ysabel (15 October 2012) [http://www.ecomagination.com/testing-the-waters-gaining-public-support-for-offshore-wind Testing the Waters: Gaining Public Support for Offshore Wind] {{Webarchive|url=https://web.archive.org/web/20130119023610/http://www.ecomagination.com/testing-the-waters-gaining-public-support-for-offshore-wind |date=19 January 2013 }}. ecomagination.com</ref> As well as concerns about the landscape, there are concerns that some installations can produce excessive sound and vibration levels leading to a decrease in property values.<ref>{{cite web |url=http://rivercitymalone.com/wind-energy/town-councilor-regrets-wind-farm-high-sheldon-windfarm-ny/ |title=Town Councilor regrets High Sheldon Wind Farm (Sheldon, NY) |author1=Cramer, Glenn |date=30 October 2009 |access-date=4 September 2015 |archive-date=24 September 2015 |archive-url=https://web.archive.org/web/20150924154038/http://rivercitymalone.com/wind-energy/town-councilor-regrets-wind-farm-high-sheldon-windfarm-ny/ |url-status=live }}</ref> A study of 50,000 home sales near wind turbines found no statistical evidence that prices were affected.<ref>Ben Hoen, Jason P. Brown, Thomas Jackson, Ryan Wiser, Mark Thayer and Peter Cappers. "[http://www.nwea.nl/sites/default/files/WOZ%20-%20Spatial%20hedonic%20analysis%20on%20surrounding%20property%20values%20%28Berkely%202013%29.pdf A Spatial Hedonic Analysis of the Effects of Wind Energy Facilities on Surrounding Property Values in the United States] {{webarchive|url=https://web.archive.org/web/20151117033323/http://www.nwea.nl/sites/default/files/WOZ%20-%20Spatial%20hedonic%20analysis%20on%20surrounding%20property%20values%20%28Berkely%202013%29.pdf |date=17 November 2015 }}" p. 37. ''Lawrence Berkeley National Laboratory'', August 2013. [http://emp.lbl.gov/sites/all/files/lbnl-6362e.pdf Mirror] {{Webarchive|url=https://web.archive.org/web/20151118004839/https://emp.lbl.gov/sites/all/files/lbnl-6362e.pdf |date=18 November 2015 }}</ref>
While aesthetic issues are subjective and some find wind farms pleasant and optimistic, or symbols of energy independence and local prosperity, protest groups are often formed to attempt to block some wind power stations for various reasons.<ref name="wind-watch.org">{{cite web | url=http://www.wind-watch.org/affiliates.php | title=Wind Energy Opposition and Action Groups | publisher=Wind-watch.org | access-date=11 January 2013 | archive-date=5 May 2012 | archive-url=https://web.archive.org/web/20120505130436/http://www.wind-watch.org/affiliates.php | url-status=live }}</ref><ref name="guardian.co.uk">Gourlay, Simon (12 August 2008) [https://www.theguardian.com/commentisfree/2008/aug/12/windpower.alternativeenergy Wind Farms Are Not Only Beautiful, They're Absolutely Necessary] {{Webarchive|url=https://web.archive.org/web/20131005070554/http://www.theguardian.com/commentisfree/2008/aug/12/windpower.alternativeenergy |date=5 October 2013 }}, ''The Guardian''.</ref><ref name="guardianQA">Aldred, Jessica (10 December 2007) [https://www.theguardian.com/environment/2007/dec/10/windpower.renewableenergy Q&A: Wind Power] {{Webarchive|url=https://web.archive.org/web/20160313235603/http://www.theguardian.com/environment/2007/dec/10/windpower.renewableenergy |date=13 March 2016 }}, ''The Guardian''.</ref>
Some opposition to wind farms is dismissed as NIMBYism,<ref>{{cite news | url=https://www.thestar.com/comment/article/519708 | work=Toronto Star | location=Toronto | title=Windmills vs. NIMBYism | date=20 October 2008 | access-date=18 September 2017 | archive-date=11 October 2012 | archive-url=https://web.archive.org/web/20121011113357/http://www.thestar.com/comment/article/519708 | url-status=live }}</ref> but research carried out in 2009 found that there is little evidence to support the belief that residents only object to wind farms because of a "Not in my Back Yard" attitude.<ref>{{cite web | url=http://www.businessgreen.com/bg/news/1807322/wind-industry-avoid-branding-opponents-nimbys | title=Wind industry should avoid branding opponents "Nimbys" | last=Donoghue | first=Andrew | date=30 July 2009 | website=Business Green | access-date=13 April 2012 | archive-date=2 January 2012 | archive-url=https://web.archive.org/web/20120102085646/http://www.businessgreen.com/bg/news/1807322/wind-industry-avoid-branding-opponents-nimbys | url-status=live }}</ref>
=== Geopolitics === Wind cannot be cut off unlike oil and gas so can contribute to energy security.<ref>{{Cite web |date=2022-03-09 |title=Why onshore wind, not fracking, offers Boris Johnson a better weapon against Vladimir Putin |url=https://inews.co.uk/opinion/fracking-onshore-wind-boris-johnson-uk-weapon-against-vladimir-putin-1506705 |access-date=2022-04-02 |website=inews.co.uk |language=en}}</ref>
== Turbine design == {{main|Wind turbine|Wind turbine design}} {{see also|Wind-turbine aerodynamics}} {{stack|float=right| [[File:Wind turbine int.svg|thumb| Typical wind turbine components: {{ordered list |1=Foundation |2=Connection to the electric grid |3=Tower |4=Access ladder |5=Wind orientation control (yaw control) |6=Nacelle |7=Generator |8=Anemometer |9=Electric or mechanical brake |10=Gearbox |11=Rotor blade |12=Blade pitch control |13=Rotor hub }}]] |thumb|right|Typical components of a wind turbine (gearbox, rotor shaft and brake assembly) being lifted into position}}
Wind turbines are devices that convert the wind's kinetic energy into electrical power. The result of over a millennium of windmill development and modern engineering, today's wind turbines are manufactured in a wide range of horizontal axis and vertical axis types. The smallest turbines are used for applications such as battery charging for auxiliary power. Slightly larger turbines can be used for making small contributions to a domestic power supply while selling unused power back to the utility supplier via the electrical grid. Arrays of large turbines, known as wind farms, have become an increasingly important source of renewable energy and are used by many countries to reduce their reliance on fossil fuels.
Wind turbine design is the process of defining the form and specifications of a wind turbine to extract energy from the wind.<ref>{{cite web | publisher =UK Department for Business, Enterprise & Regulatory Reform | title =Efficiency and performance |url=http://www.berr.gov.uk/files/file17821.pdf | access-date =29 December 2007 | archive-url =https://web.archive.org/web/20090205054846/http://www.berr.gov.uk/files/file17821.pdf | archive-date =5 February 2009}}</ref> A wind turbine installation consists of the necessary systems needed to capture the wind's energy, point the turbine into the wind, convert mechanical rotation into electrical power, and other systems to start, stop, and control the turbine.
In 1919, the German physicist Albert Betz showed that for a hypothetical ideal wind-energy extraction machine, the fundamental laws of conservation of mass and energy allowed no more than 16/27 (59%) of the kinetic energy of the wind to be captured. This Betz limit can be approached in modern turbine designs, which may reach 70 to 80% of the theoretical Betz limit.<ref>Betz, A.; Randall, D. G. (trans.). ''Introduction to the Theory of Flow Machines'', Oxford: Pergamon Press, 1966.</ref><ref>Burton, Tony, et al., (ed). [https://books.google.com/books?id=qVjtDxyN-joC ''Wind Energy Handbook''] {{Webarchive|url=https://web.archive.org/web/20160105145500/https://books.google.com/books?id=qVjtDxyN-joC |date=5 January 2016 }}, John Wiley and Sons, 2001, {{ISBN|0-471-48997-2}}, p. 65.</ref>
The aerodynamics of a wind turbine are not straightforward. The airflow at the blades is not the same as the airflow far away from the turbine. The very nature of how energy is extracted from the air also causes air to be deflected by the turbine. This affects the objects or other turbines downstream, which is known as "wake effect". Also, the aerodynamics of a wind turbine at the rotor surface exhibit phenomena that are rarely seen in other aerodynamic fields. The shape and dimensions of the blades of the wind turbine are determined by the aerodynamic performance required to efficiently extract energy from the wind, and by the strength required to resist the forces on the blade.<ref>{{cite web | url=http://www.alternative-energy-news.info/what-factors-affect-the-output-of-wind-turbines/ | title=What factors affect the output of wind turbines? | publisher=Alternative-energy-news.info | date=24 July 2009 | access-date=6 November 2013 | archive-date=29 September 2018 | archive-url=https://web.archive.org/web/20180929021418/http://www.alternative-energy-news.info/what-factors-affect-the-output-of-wind-turbines/ | url-status=live }}</ref>
In addition to the aerodynamic design of the blades, the design of a complete wind power system must also address the design of the installation's rotor hub, nacelle, tower structure, generator, controls, and foundation.<ref>{{cite web |author1=Zehnder, Alan T. |author2=Warhaft, Zellman |name-list-style=amp |title=University Collaboration on Wind Energy |date=27 July 2011 |url=https://www.sustainablefuture.cornell.edu/attachments/2011-UnivWindCollaboration.pdf |publisher=Cornell University Atkinson Center for a Sustainable Future |access-date=22 August 2011 |archive-url=https://web.archive.org/web/20110901005908/http://www.sustainablefuture.cornell.edu/attachments/2011-UnivWindCollaboration.pdf |archive-date=1 September 2011 }}</ref>
== History == {{Main|History of wind power}} [[File: Wind turbine 1888 Charles Brush.jpg|thumb|Charles F. Brush's wind turbine of 1888, used for generating electric power.]]{{See also|Renewable energy commercialization#Wind power}} Wind power has been used as long as humans have put sails into the wind. Wind-powered machines used to grind grain and pump water, the windmill and wind pump, were developed in what is now Iran, Afghanistan, and Pakistan by the 9th century.<ref>Ahmad Y Hassan, Donald Routledge Hill (1986). ''Islamic Technology: An illustrated history'', p. 54. Cambridge University Press. {{ISBN|0-521-42239-6}}.</ref><ref>{{citation|last=Lucas|first=Adam|title=Wind, Water, Work: Ancient and Medieval Milling Technology|page=65|year=2006|publisher=Brill Publishers|isbn=90-04-14649-0}}</ref> Wind power was widely available and not confined to the banks of fast-flowing streams, or later, requiring sources of fuel. Wind-powered pumps drained the polders of the Netherlands, and in arid regions such as the American mid-west or the Australian outback, wind pumps provided water for livestock and steam engines.
The first wind turbine used for the production of electric power was built in Scotland in July 1887 by Prof James Blyth of Anderson's College, Glasgow (the precursor of Strathclyde University).<ref name="Price">{{Cite journal|last=Price|first=Trevor J|date=3 May 2005|title=James Blyth – Britain's First Modern Wind Power Engineer|journal=Wind Engineering|volume=29|issue=3|pages=191–200|doi=10.1260/030952405774354921|s2cid=110409210}}</ref> Blyth's {{convert|10|m|ft}} high cloth-sailed wind turbine was installed in the garden of his holiday cottage at Marykirk in Kincardineshire, and was used to charge accumulators developed by the Frenchman Camille Alphonse Faure, to power the lighting in the cottage,<ref name="Price" /> thus making it the first house in the world to have its electric power supplied by wind power.<ref>{{cite web|last=Shackleton|first=Jonathan|title=World First for Scotland Gives Engineering Student a History Lesson|url=http://www.rgu.ac.uk/pressrel/BlythProject.doc|archive-url=https://web.archive.org/web/20081217063550/http://www.rgu.ac.uk/pressrel/BlythProject.doc|archive-date=17 December 2008|access-date=20 November 2008|publisher=The Robert Gordon University}}</ref> Blyth offered the surplus electric power to the people of Marykirk for lighting the main street, however, they turned down the offer as they thought electric power was "the work of the devil".<ref name="Price" /> Although he later built a wind turbine to supply emergency power to the local Lunatic Asylum, Infirmary, and Dispensary of Montrose, the invention never really caught on as the technology was not considered to be economically viable.<ref name="Price" />
Across the Atlantic, in Cleveland, Ohio, a larger and heavily engineered machine was designed and constructed in the winter of 1887–1888 by Charles F. Brush.<ref>Anon. [http://www.scientificamerican.com/article/mr-brushs-windmill-dynamo/ Mr. Brush's Windmill Dynamo] {{Webarchive|url=https://web.archive.org/web/20170707215932/https://www.scientificamerican.com/article/mr-brushs-windmill-dynamo/ |date=7 July 2017 }}, ''Scientific American'', Vol. 63 No. 25, 20 December 1890, p. 54.</ref> This was built by his engineering company at his home and operated from 1886 until 1900.<ref>[http://www.windpower.org/en/pictures/brush.htm A Wind Energy Pioneer: Charles F. Brush] {{webarchive|url=https://web.archive.org/web/20080908061207/http://www.windpower.org/en/pictures/brush.htm|date=8 September 2008}}, Danish Wind Industry Association. Accessed 2 May 2007.</ref> The Brush wind turbine had a rotor {{convert|17|m|ft}} in diameter and was mounted on an 18-metre (59ft) tall tower. Although large by today's standards, the machine was only rated at 12 kW. The connected dynamo was used either to charge a bank of batteries or to operate up to 100 incandescent light bulbs, three arc lamps, and various motors in Brush's laboratory.<ref>"History of Wind Energy" in Cutler J. Cleveland (ed.) ''Encyclopedia of Energy''. Vol. 6, Elsevier, {{ISBN|978-1-60119-433-6}}, 2007, pp. 421–22</ref> With the development of electric power, wind power found new applications in lighting buildings remote from centrally generated power. Throughout the 20th century parallel paths developed small wind stations suitable for farms or residences. From 1932 many isolated properties in Australia ran their lighting and electric fans from batteries, charged by a "Freelite" wind-driven generator, producing 100{{nbsp}}watts of electrical power from as little wind speed as {{convert|10|mph}}.<ref>{{cite news |url=http://nla.gov.au/nla.news-article37240794 |title="Freelite" |newspaper=The Longreach Leader |volume=11 |issue=561 |location=Queensland, Australia |date=16 December 1933 |access-date=26 March 2023 |page=5 |via=National Library of Australia}}</ref>
The 1973 oil crisis triggered the investigation in Denmark and the United States that led to larger utility-scale wind generators that could be connected to electric power grids for remote use of power. By 2008, the U.S. installed capacity had reached 25.4 gigawatts, and by 2012 the installed capacity was 60 gigawatts.<ref>{{cite web|title=History of U.S. Wind Energy|url=https://www.energy.gov/eere/wind/history-us-wind-energy|access-date=10 December 2019|website=Energy.gov|language=en|archive-date=15 December 2019|archive-url=https://web.archive.org/web/20191215133631/https://www.energy.gov/eere/wind/history-us-wind-energy|url-status=live}}</ref> Today, wind-powered generators operate in every size range, from tiny stations for battery charging at isolated residences, up to gigawatt-sized offshore wind farms that provide electric power to national electrical networks. The European Union is working to augment these prospects.<ref>{{cite news |last= Widder |first= Jonathan |date= 25 October 2023|title= Saubere Energie unaufhaltsam, EU beschleunigt Windkraft-Ausbau, Luchse zurück nach Sachsen|url= https://squirrel-news.net/de/news/saubere-energie-unaufhaltsam-eu-beschleunigt-windkraft-ausbau-luchse-zurueck-nach-sachsen/|work= Squirrel News|access-date=7 March 2024}}</ref>
In 2023, the global wind power sector experienced significant growth, with 116.6 gigawatts (GW) of new capacity added to the power grid, representing a 50% increase over the amount added in 2022. This surge in capacity brought the total installed wind power capacity worldwide to 1,021 GW by the end of the year, marking a growth of 13% compared to the previous year.<ref>{{Cite web |last=Alex |date=2024-04-15 |title=Global Wind Report 2024 |url=https://gwec.net/global-wind-report-2024/ |access-date=2024-04-18 |website=Global Wind Energy Council |language=en-US}}</ref>{{Rp|page=138}}
== See also ==
{{stack|float=right|{{Portal|Wind power|Renewable energy|Energy}}}} {{Div col}} * 100% renewable energy * Global Wind Day * Hydrogen economy * List of countries by renewable electricity production * List of renewable energy journals * List of wind turbine manufacturers * List of offshore wind farms * Lists of wind farms * Outline of wind energy * Wind power by country * Wind resource assessment * Wind-powered vehicle {{div col end}}
== Notes ==
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== References == {{reflist}}
== External links ==
{{Commons category|Wind power}} * {{official website|http://gwec.net/}} of Global Wind Energy Council (GWEC) * [https://regeneration.org/index.php/nexus/wind Wind] from Project Regeneration * {{official website|https://wwindea.org/}} of World Wind Energy Association (WWEA) * [https://www.iea.org/data-and-statistics/data-tools/renewables-2021-data-explorer?mode=market®ion=World&publication=2021&product=Total Dynamic Data Dashboard] from the International Energy Agency * [https://earth.nullschool.net/#current/wind/isobaric/1000hPa/overlay=wind_power_density/winkel3 Current global map of wind power density]
{{footer energy}} {{Wind power}} {{Wind power by country}} {{Electricity delivery|state=collapsed}} {{Application of wind energy}} {{Renewable energy by country}} {{Natural resources}}
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Category:Bright green environmentalism Category:Wind power Category:Renewable energy