Wind is the natural movement of air or other gases relative to a planet's surface . Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few hours, to global winds resulting from the difference in absorption of solar energy between the climate zones on Earth . The two main causes of large-scale atmospheric circulation are the differential heating between the equator and the poles, and the rotation of the planet ( Coriolis effect ). Within the tropics and subtropics, thermal low circulations over terrain and high plateaus can drive monsoon circulations. In coastal areas the sea breeze /land breeze cycle can define local winds; in areas that have variable terrain, mountain and valley breezes can prevail.
134-439: The World Wind Energy Association ( WWEA ) is an international non-profit association representing the wind power sector worldwide, with members in 100 countries, amongst them the leading national and regional wind energy associations. The organisation works for the promotion and worldwide deployment of wind energy technology and advocates a future energy system based on renewable energy . The World Wind Energy Association WWEA
268-536: A difference in atmospheric pressure exists, air moves from the higher to the lower pressure area, resulting in winds of various speeds. On a rotating planet, air will also be deflected by the Coriolis effect , except exactly on the equator. Globally, the two major driving factors of large-scale wind patterns (the atmospheric circulation ) are the differential heating between the equator and the poles (difference in absorption of solar energy leading to buoyancy forces ) and
402-418: 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 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. At a substation, this medium-voltage electric current is increased in voltage with
536-620: A transformer for connection to the high voltage electric power transmission system. 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. 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. Black start
670-424: A combination of wind and cold temperatures, when winds exceed 40 kilometers per hour (25 mph), rendering their hair and wool coverings ineffective. Although penguins use both a layer of fat and feathers to help guard against coldness in both water and air, their flippers and feet are less immune to the cold. In the coldest climates such as Antarctica , emperor penguins use huddling behavior to survive
804-748: A different continent every year. WWECs have been held in Berlin (Germany) in 2002, Cape Town (South Africa) in 2003, and Beijing (China) in 2004. The 3rd WWEC in Beijing was attended by over 2000 participants thus becoming the biggest wind event ever held outside the EU and the US. The 4th WWEC took place in Melbourne (Australia). The 5th WWEC in New Delhi, India, from 6–8 November 2006, had the participation of nearly 2000 delegates from all over
938-511: A gale, a storm, or a hurricane. Within the Beaufort scale, gale-force winds lie between 28 knots (52 km/h) and 55 knots (102 km/h) with preceding adjectives such as moderate, fresh, strong, and whole used to differentiate the wind's strength within the gale category. A storm has winds of 56 knots (104 km/h) to 63 knots (117 km/h). The terminology for tropical cyclones differs from one region to another globally. Most ocean basins use
1072-514: 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
1206-586: A large potential as wind speeds are typically higher and more constant away from the coast. Wind energy the kinetic energy of the air, is proportional to the third power of wind velocity. Betz's law described the theoretical upper limit of what fraction of this energy wind turbines can extract, which is about 59%. Wind figures prominently in several popular sports, including recreational hang gliding , hot air ballooning , kite flying, snowkiting , kite landboarding , kite surfing , paragliding , sailing , and windsurfing . In gliding, wind gradients just above
1340-473: A mechanical sandblaster in a laboratory setting, scientists affiliated with the Agricultural Research Service studied the effects of windblown sand abrasion on cotton seedlings. The study showed that the seedlings responded to the damage created by the windblown sand abrasion by shifting energy from stem and root growth to the growth and repair of the damaged stems. After a period of four weeks,
1474-479: A power system that has the potential to meet power supply needs reliably. Integrating ever-higher levels of renewables is being successfully demonstrated in the real world. Solar power tends to be complementary to wind. 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
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#17328594305571608-405: A probability distribution function is often fit to the observed wind speed data. 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. A wind farm
1742-425: A share of about 10% of new installations. 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 . Regions in the higher northern and southern latitudes have the highest potential for wind power. In most regions, wind power generation is higher in nighttime, and in winter when solar power output
1876-771: A significant effect on the control of aircraft during take-off and landing, and was a significant cause of aircraft accidents involving large loss of life within the United States. Sound movement through the atmosphere is affected by wind shear, which can bend the wave front, causing sounds to be heard where they normally would not, or vice versa. Strong vertical wind shear within the troposphere also inhibits tropical cyclone development, but helps to organize individual thunderstorms into living longer life cycles that can then produce severe weather . The thermal wind concept explains how differences in wind speed with height are dependent on horizontal temperature differences, and explains
2010-530: A system fault. 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. As of November 2021, the Hornsea Wind Farm in the United Kingdom
2144-435: 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 thus sustaining the circulation of the atmosphere against friction. 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
2278-433: A variety of aeolian processes such as the formation of fertile soils, for example loess , and by erosion . Dust from large deserts can be moved great distances from its source region by the prevailing winds ; winds that are accelerated by rough topography and associated with dust outbreaks have been assigned regional names in various parts of the world because of their significant effects on those regions. Wind also affects
2412-499: A wind barb to show both wind direction and speed. The wind barb shows the speed using "flags" on the end. Winds are depicted as blowing from the direction the barb is facing. Therefore, a northeast wind will be depicted with a line extending from the cloud circle to the northeast, with flags indicating wind speed on the northeast end of this line. Once plotted on a map, an analysis of isotachs (lines of equal wind speeds) can be accomplished. Isotachs are particularly useful in diagnosing
2546-528: Is a microscale meteorological phenomenon occurring over a very small distance, but it can be associated with mesoscale or synoptic scale weather features such as squall lines and cold fronts . It is commonly observed near microbursts and downbursts caused by thunderstorms , weather fronts, areas of locally higher low level winds referred to as low level jets, near mountains, radiation inversions that occur because of clear skies and calm winds, buildings, wind turbines , and sailboats . Wind shear has
2680-463: Is a difference in wind speed and direction over a relatively short distance in the Earth's atmosphere. Wind shear can be broken down into vertical and horizontal components, with horizontal wind shear seen across weather fronts and near the coast, and vertical shear typically near the surface, though also at higher levels in the atmosphere near upper level jets and frontal zones aloft. Wind shear itself
2814-420: 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
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#17328594305572948-451: Is an increase of the wind speed above a certain threshold, which lasts for a minute or more. To determine winds aloft, radiosondes determine wind speed by GPS , radio navigation , or radar tracking of the probe. Alternatively, movement of the parent weather balloon position can be tracked from the ground visually using theodolites . Remote sensing techniques for wind include SODAR , Doppler lidars and radars, which can measure
3082-592: Is considered a sustainable , renewable energy source, and has a much smaller impact on the environment compared to 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. Wind farms sited offshore have less visual impact and have higher capacity factors , although they are generally more expensive. Offshore wind power currently has
3216-427: Is exposed to the wind to determine the dynamic pressure, which is then used to compute the wind speed. Sustained wind speeds are reported globally at a 10-meter (33 ft) height and are averaged over a 10‑minute time frame. The United States reports winds over a 1‑minute average for tropical cyclones, and a 2‑minute average within weather observations. India typically reports winds over a 3‑minute average. Knowing
3350-477: Is generally the primary factor governing the direction of flight operations at an airport, and airfield runways are aligned to account for the common wind direction(s) of the local area. While taking off with a tailwind may be necessary under certain circumstances, a headwind is generally desirable. A tailwind increases takeoff distance required and decreases the climb gradient. The ancient Sinhalese of Anuradhapura and in other cities around Sri Lanka used
3484-746: Is governed by a board currently consisting of the President Peter Rae , Australia, and Vice Presidents from all continents. A complete list of the WWEA board members which represent all continents can be found on the WWEA website www.wwindea.org. The WWEA Head Office is situated in Bonn , close to the UN Campus, managed by the Secretary-General Stefan Gsänger . WWEA is the voice supporting wind energy and other renewables at energy conferences and in
3618-599: Is insufficient rainfall to support vegetation. An example is the formation of sand dunes , on a beach or in a desert. Loess is a homogeneous, typically nonstratified, porous, friable , slightly coherent, often calcareous, fine-grained, silty , pale yellow or buff, windblown (Aeolian) sediment . It generally occurs as a widespread blanket deposit that covers areas of hundreds of square kilometers and tens of meters thick. Loess often stands in either steep or vertical faces. Loess tends to develop into highly rich soils. Under appropriate climatic conditions, areas with loess are among
3752-403: Is low. For this reason, combinations of wind and solar power are suitable in many countries. 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 A {\displaystyle A} is A v {\displaystyle Av} . If the air density is ρ {\displaystyle \rho } ,
3886-480: Is lower in summer and higher in winter. Thus the seasonal variation of wind and solar power tend to cancel each other somewhat. Wind hybrid power systems are becoming more popular. 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. In summer 2021, wind power in the United Kingdom fell due to
4020-542: Is not the primary form of seed dispersal in plants, it provides dispersal for a large percentage of the biomass of land plants. Erosion can be the result of material movement by the wind. There are two main effects. First, wind causes small particles to be lifted and therefore moved to another region. This is called deflation. Second, these suspended particles may impact on solid objects causing erosion by abrasion (ecological succession). Wind erosion generally occurs in areas with little or no vegetation, often in areas where there
4154-474: Is one of the more primitive means of dispersal. Wind dispersal can take on one of two primary forms: seeds can float on the breeze or alternatively, they can flutter to the ground. The classic examples of these dispersal mechanisms include dandelions ( Taraxacum spp., Asteraceae ), which have a feathery pappus attached to their seeds and can be dispersed long distances, and maples ( Acer (genus) spp., Sapindaceae ), which have winged seeds and flutter to
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4288-412: Is possible and is being further developed for places (such as Iowa ) which generate most of their electricity from wind. 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
4422-746: Is sent to the rest of the British grid . 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, steel, or natural gas, and hydrogen, and using future long-term storage to facilitate 100% energy from variable renewable energy . Homes and businesses can also be programmed to vary electricity demand , for example by remotely turning up water heater thermostats. Wind power
4556-425: Is similar to the geostrophic wind but also includes centrifugal force (or centripetal acceleration ). Wind direction is usually expressed in terms of the direction from which it originates. For example, a northerly wind blows from the north to the south. Weather vanes pivot to indicate the direction of the wind. At airports, windsocks indicate wind direction, and can also be used to estimate wind speed by
4690-415: Is the largest offshore wind farm in the world at 1,218 MW . Near offshore wind farms may be connected by AC and far offshore by HVDC. Wind power resources are not always located near to 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
4824-503: Is the movement of gases or charged particles from the Sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space. The strongest observed winds on a planet in the Solar System occur on Neptune and Saturn . In human civilization, the concept of wind has been explored in mythology , influenced the events of history, expanded
4958-459: 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 with wind turbines , generally grouped into wind farms and connected to the electrical grid . In 2022, wind supplied over 2,304 TWh of electricity, which
5092-449: 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
5226-407: Is warmed by the sun more slowly because of water's greater specific heat compared to land. As the temperature of the surface of the land rises, the land heats the air above it by conduction. The warm air is less dense than the surrounding environment and so it rises. The cooler air above the sea, now with higher sea level pressure , flows inland into the lower pressure, creating a cooler breeze near
5360-495: The Doppler shift of electromagnetic radiation scattered or reflected off suspended aerosols or molecules , and radiometers and radars can be used to measure the surface roughness of the ocean from space or airplanes. Ocean roughness can be used to estimate wind velocity close to the sea surface over oceans. Geostationary satellite imagery can be used to estimate the winds at cloud top based upon how far clouds move from one image to
5494-560: The Gobi Desert , which combined with pollutants, spread large distances downwind, or eastward, into North America. There are local names for winds associated with sand and dust storms. The Calima carries dust on southeast winds into the Canary islands . The Harmattan carries dust during the winter into the Gulf of Guinea . The Sirocco brings dust from north Africa into southern Europe because of
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5628-852: The International Solar Energy Society (ISES), the International Geothermal Association (IGA) and since June 2009 the World Bioenergy Association (WBA). WWEA cooperates with other international renewable energy organizations; for example, it is represented at the Steering Committee of the REN21 global policy network and is a member of the World Council for Renewable Energy (WCRE). WWEA organises World Wind Energy Conferences and Exhibitions (WWECs) in
5762-471: The Magnus effect , every sailing ship has a hull , rigging and at least one mast to hold up the sails that use the wind to power the ship. Ocean journeys by sailing ship can take many months, and a common hazard is becoming becalmed because of lack of wind, or being blown off course by severe storms or winds that do not allow progress in the desired direction. A severe storm could lead to shipwreck , and
5896-544: The North African Campaign of the World War II, "allied and German troops were several times forced to halt in mid-battle because of sandstorms caused by khamsin... Grains of sand whirled by the wind blinded the soldiers and created electrical disturbances that rendered compasses useless." There are many different forms of sailing ships, but they all have certain basic things in common. Except for rotor ships using
6030-482: The Paris Agreement 's goals to limit climate change , analysts say it should expand much faster – by over 1% of electricity generation per year. Expansion of wind power is being hindered by fossil fuel subsidies . 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
6164-654: The Technical University of Denmark in partnership with the World Bank provides a global assessment of wind power potential. 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. More detailed, site-specific assessments of wind resource potential can be obtained from specialist commercial providers, and many of
6298-400: The atmospheric boundary layer in the midlatitudes. The thermal wind is the difference in the geostrophic wind between two levels in the atmosphere. It exists only in an atmosphere with horizontal temperature gradients . The ageostrophic wind component is the difference between actual and geostrophic wind, which is responsible for air "filling up" cyclones over time. The gradient wind
6432-494: The gristmilling and sugarcane industries. Horizontal-axle windmills were later used extensively in Northwestern Europe to grind flour beginning in the 1180s, and many Dutch windmills still exist. Wind power is now one of the main sources of renewable energy , and its use is growing rapidly, driven by innovation and falling prices. Most of the installed capacity in wind power is onshore , but offshore wind power offers
6566-464: The leeward or downwind side. Moisture is removed by orographic lift, leaving drier air on the descending and generally warming, leeward side where a rain shadow is observed. Winds that flow over mountains down into lower elevations are known as downslope winds. These winds are warm and dry. In Europe downwind of the Alps , they are known as foehn . In Poland, an example is the halny wiatr. In Argentina,
6700-496: The logarithmic wind profile , can be utilized to derive vertical information. Temporal information is typically computed by solving the Navier-Stokes equations within numerical weather prediction models, generating global data for General Circulation Models or specific regional data. The calculation of wind fields is influenced by factors such as radiation differentials, Earth's rotation, and friction, among others. Solving
6834-494: The polar regions . The westerlies can be particularly strong, especially in the southern hemisphere, where there is less land in the middle latitudes to cause the flow pattern to amplify, which slows the winds down. The strongest westerly winds in the middle latitudes are within a band known as the Roaring Forties , between 40 and 50 degrees latitude south of the equator. The Westerlies play an important role in carrying
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#17328594305576968-402: The rotation of the planet . Outside the tropics and aloft from frictional effects of the surface, the large-scale winds tend to approach geostrophic balance . Near the Earth's surface, friction causes the wind to be slower than it would be otherwise. Surface friction also causes winds to blow more inward into low-pressure areas. Winds defined by an equilibrium of physical forces are used in
7102-548: 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 over the period from 1979 to 2010, 1.31 MJ/m in the Northern Hemisphere with 1.70 MJ/m in the Southern Hemisphere. The atmosphere acts as
7236-400: The windward side of mountains and is caused by the rising air motion of a large-scale flow of moist air across the mountain ridge, also known as upslope flow, resulting in adiabatic cooling and condensation. In mountainous parts of the world subjected to relatively consistent winds (for example, the trade winds), a more moist climate usually prevails on the windward side of a mountain than on
7370-566: The African dust that reaches the United States affects Florida. Since 1970, dust outbreaks have worsened because of periods of drought in Africa. There is a large variability in the dust transport to the Caribbean and Florida from year to year. Dust events have been linked to a decline in the health of coral reefs across the Caribbean and Florida, primarily since the 1970s. Similar dust plumes originate in
7504-449: The Caribbean into southeastern North America. When dust from the Sahara moving around the southern periphery of the ridge within the belt of trade winds moves over land, rainfall is suppressed and the sky changes from a blue to a white appearance, which leads to an increase in red sunsets. Its presence negatively impacts air quality by adding to the count of airborne particulates. Over 50% of
7638-453: The Earth's complex atmospheric system. Historically, the Beaufort wind force scale (created by Beaufort ) provides an empirical description of wind speed based on observed sea conditions. Originally it was a 13-level scale (0–12), but during the 1940s, the scale was expanded to 18 levels (0–17). There are general terms that differentiate winds of different average speeds such as a breeze,
7772-425: The Earth's deserts lie near the average latitude of the subtropical ridge, where descent reduces the relative humidity of the air mass. The strongest winds are in the mid-latitudes where cold polar air meets warm air from the tropics. The trade winds (also called trades) are the prevailing pattern of easterly surface winds found in the tropics towards the Earth's equator . The trade winds blow predominantly from
7906-556: The Navier-Stokes equations is a time-consuming numerical process, but machine learning techniques can help expedite computation time. Numerical weather prediction models have significantly advanced our understanding of atmospheric dynamics and have become indispensable tools in weather forecasting and climate research. By leveraging both spatial and temporal data, these models enable scientists to analyze and predict global and regional wind patterns, contributing to our comprehension of
8040-463: The Prevailing Westerlies are the prevailing winds in the middle latitudes between 35 and 65 degrees latitude . These prevailing winds blow from the west to the east, and steer extratropical cyclones in this general manner. The winds are predominantly from the southwest in the Northern Hemisphere and from the northwest in the Southern Hemisphere. They are strongest in the winter when
8174-583: The United States, and they can be as strong as other downslope winds and unusual compared to other foehn winds in that the relative humidity typically changes little due to the increased moisture in the source air mass. In California, downslope winds are funneled through mountain passes, which intensify their effect, and examples include the Santa Ana and sundowner winds. Wind speeds during downslope wind effect can exceed 160 kilometers per hour (99 mph). Wind shear, sometimes referred to as wind gradient ,
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#17328594305578308-540: The Westerlies, these prevailing winds blow from the east to the west, and are often weak and irregular. Because of the low sun angle, cold air builds up and subsides at the pole creating surface high-pressure areas, forcing an equatorward outflow of air; that outflow is deflected westward by the Coriolis effect. In coastal regions, sea breezes and land breezes can be important factors in a location's prevailing winds. The sea
8442-451: The airspeed to deal with the effect of the gradient. When landing, wind shear is also a hazard, particularly when the winds are strong. As the glider descends through the wind gradient on final approach to landing, airspeed decreases while sink rate increases, and there is insufficient time to accelerate prior to ground contact. The pilot must anticipate the wind gradient and use a higher approach speed to compensate for it. In arid climates,
8576-468: The angle of hang. Wind speed is measured by anemometers , most commonly using rotating cups or propellers. When a high measurement frequency is needed (such as in research applications), wind can be measured by the propagation speed of ultrasound signals or by the effect of ventilation on the resistance of a heated wire. Another type of anemometer uses pitot tubes that take advantage of the pressure differential between an inner tube and an outer tube that
8710-530: The average wind speed to determine the tropical cyclone's category. Below is a summary of the classifications used by Regional Specialized Meteorological Centers worldwide: The Enhanced Fujita Scale (EF Scale) rates the strength of tornadoes by using damage to estimate wind speed. It has six levels, from visible damage to complete destruction. It is used in the United States and in some other countries, including Canada and France, with small modifications. The station model plotted on surface weather maps uses
8844-400: The biggest current challenges to wind power grid integration in some countries is the necessity of developing new transmission lines to carry power from wind farms, usually in remote lowly populated areas due to availability of wind, to high load locations, usually on the coasts where population density is higher. Any existing transmission lines in remote locations may not have been designed for
8978-700: The capacity factor can be calculated from the yearly output. 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%, up from 3.5% in 2015. 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
9112-406: The capacity factors for wind installations are in the range of 35% to 44%. 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
9246-550: The coast, such as the Sitka spruce and sea grape , are pruned back by wind and salt spray near the coastline. Wind can also cause plants damage through sand abrasion . Strong winds will pick up loose sand and topsoil and hurl it through the air at speeds ranging from 25 miles per hour (40 km/h) to 40 miles per hour (64 km/h). Such windblown sand causes extensive damage to plant seedlings because it ruptures plant cells, making them vulnerable to evaporation and drought. Using
9380-400: The coast. A background along-shore wind either strengthens or weakens the sea breeze, depending on its orientation with respect to the Coriolis force. At night, the land cools off more quickly than the ocean because of differences in their specific heat values. This temperature change causes the daytime sea breeze to dissipate. When the temperature onshore cools below the temperature offshore,
9514-514: The construction and operating phase. Jobs include the manufacturing of wind turbines and the construction process, which includes transporting, installing, and then maintaining the turbines. An estimated 1.25 million people were employed in wind power in 2020. Wind Winds are commonly classified by their spatial scale , their speed and direction, the forces that cause them, the regions in which they occur, and their effect. Winds have various defining aspects such as velocity ( wind speed ),
9648-712: 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%. 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
9782-400: The decomposition and analysis of wind profiles. They are useful for simplifying the atmospheric equations of motion and for making qualitative arguments about the horizontal and vertical distribution of horizontal winds. The geostrophic wind component is the result of the balance between Coriolis force and pressure gradient force. It flows parallel to isobars and approximates the flow above
9916-711: The density of the gases involved, and energy content or wind energy . In meteorology , winds are often referred to according to their strength, and the direction from which the wind is blowing. The convention for directions refer to where the wind comes from; therefore, a 'western' or 'westerly' wind blows from the west to the east, a 'northern' wind blows south, and so on. This is sometimes counter-intuitive. Short bursts of high speed wind are termed gusts . Strong winds of intermediate duration (around one minute) are termed squalls . Long-duration winds have various names associated with their average strength, such as breeze , gale , storm , and hurricane . In outer space , solar wind
10050-511: The eight directions. Kamikaze is a Japanese word, usually translated as divine wind, believed to be a gift from the gods. The term is first known to have been used as the name of a pair or series of typhoons that are said to have saved Japan from two Mongol fleets under Kublai Khan that attacked Japan in 1274 and again in 1281. Protestant Wind is a name for the storm that deterred the Spanish Armada from an invasion of England in 1588 where
10184-399: The electric-power network to be readied for the predictable variations in production that occur. It is thought that the most reliable low-carbon electricity systems will include a large share of wind power. Typically, conventional hydroelectricity complements wind power very well. When the wind is blowing strongly, nearby hydroelectric stations can temporarily hold back their water. When
10318-514: 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. 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. The wind energy sector can also produce jobs during
10452-417: The elimination of subsidies in many markets. As of 2021, subsidies are still often given to offshore wind. But 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 . Secondary market forces provide incentives for businesses to use wind-generated power, even if there is a premium price for
10586-457: The existence of the jet stream . As a natural force, the wind was often personified as one or more wind gods or as an expression of the supernatural in many cultures. Vayu is the Vedic and Hindu God of Wind. The Greek wind gods include Boreas , Notus , Eurus , and Zephyrus . Aeolus , in varying interpretations the ruler or keeper of the four winds, has also been described as Astraeus ,
10720-474: The export of electric power when needed. Electrical utilities continue to study the effects of large-scale penetration of wind generation on system stability. 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
10854-612: The flatter countryside. These conditions are dangerous to ascending and descending airplanes . Cool winds accelerating through mountain gaps have been given regional names. In Central America, examples include the Papagayo wind , the Panama wind, and the Tehuano wind . In Europe, similar winds are known as the Bora , Tramontane , and Mistral . When these winds blow over open waters, they increase mixing of
10988-664: The god of dusk who fathered the four winds with Eos , goddess of dawn. The ancient Greeks also observed the seasonal change of the winds, as evidenced by the Tower of the Winds in Athens . Venti are the Roman gods of the winds. Fūjin is the Japanese wind god and is one of the eldest Shinto gods. According to legend, he was present at the creation of the world and first let the winds out of his bag to clear
11122-459: The ground. An important constraint on wind dispersal is the need for abundant seed production to maximize the likelihood of a seed landing in a site suitable for germination . There are also strong evolutionary constraints on this dispersal mechanism. For instance, species in the Asteraceae on islands tended to have reduced dispersal capabilities (i.e., larger seed mass and smaller pappus) relative to
11256-597: The growth of the seedling once again became uniform throughout the plant, as it was before the windblown sand abrasion occurred. Besides plant gametes (seeds) wind also helps plants' enemies: Spores and other propagules of plant pathogens are even lighter and able to travel long distances. A few plant diseases are known to have been known to travel over marginal seas and even entire oceans. Humans are unable to prevent or even slow down wind dispersal of plant pathogens, requiring prediction and amelioration instead. Cattle and sheep are prone to wind chill caused by
11390-403: 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. 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,
11524-426: The length is increased; making it harder to transport large loads over large distances. 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. One of
11658-572: The local name for down sloped winds is zonda . In Java, the local name for such winds is koembang. In New Zealand, they are known as the Nor'west arch , and are accompanied by the cloud formation they are named after that has inspired artwork over the years. In the Great Plains of the United States, these winds are known as a chinook . Downslope winds also occur in the foothills of the Appalachian mountains of
11792-464: The location of the jet stream on upper-level constant pressure charts, and are usually located at or above the 300 hPa level. Easterly winds, on average, dominate the flow pattern across the poles, westerly winds blow across the mid-latitudes of the Earth, polewards of the subtropical ridge , while easterlies again dominate the tropics . Directly under the subtropical ridge are the doldrums, or horse latitudes, where winds are lighter. Many of
11926-459: The loss of all hands. Sailing ships can only carry a certain quantity of supplies in their hold , so they have to plan long voyages carefully to include appropriate provisions , including fresh water. For aerodynamic aircraft which operate relative to the air, winds affect groundspeed, and in the case of lighter-than-air vehicles, wind may play a significant or solitary role in their movement and ground track . The velocity of surface wind
12060-415: The low marginal costs of this technology. The effect has been identified in several European markets. For wind power plants exposed to electricity market pricing in markets with high penetration of variable renewable energy sources, profitability can be challenged. Turbine prices have fallen significantly in recent years due to tougher competitive conditions such as the increased use of energy auctions, and
12194-408: The lowest winds in seventy years, In the future, smoothing peaks by producing green hydrogen may help when wind has a larger share of generation. 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. Weather forecasting permits
12328-478: The main source of erosion is wind. The general wind circulation moves small particulates such as dust across wide oceans thousands of kilometers downwind of their point of origin, which is known as deflation. Westerly winds in the mid-latitudes of the planet drive the movement of ocean currents from west to east across the world's oceans. Wind has a very important role in aiding plants and other immobile organisms in dispersal of seeds, spores, pollen, etc. Although wind
12462-454: The manufacturers and decreasing profit margins. 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. Wind power is capital intensive but has no fuel costs. The price of wind power is therefore much more stable than
12596-708: The marginal price, by minimizing the use of expensive peaking power plants . 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. 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
12730-419: The mass of this volume of air is M = ρ A v {\displaystyle M=\rho Av} , and the power transfer, or energy transfer per second is P = 1 2 M v 2 = 1 2 ρ A v 3 {\displaystyle P={\tfrac {1}{2}}Mv^{2}={\tfrac {1}{2}}\rho Av^{3}} . Wind power is thus proportional to
12864-589: The media around the world. WWEA statements like the WWEC resolutions have been taken up in international discussions and are guiding political decision-makers. WWEA also participated in the International Conference for Renewable Energies Renewables 2004 ( Bonn , June 2004) and BIREC Beijing International Renewable Energy Conference 2005. WWEA has been granted Special Consultative Status at the United Nations in
12998-571: The monsoon winds to power furnaces as early as 300 BCE . The furnaces were constructed on the path of the monsoon winds to bring the temperatures inside up to 1,200 °C (2,190 °F). A rudimentary windmill was used to power an organ in the first century CE. Windmills were later built in Sistan , Afghanistan , from the 7th century CE. These were vertical-axle windmills, with sails covered in reed matting or cloth material. These windmills were used to grind corn and draw up water, and were used in
13132-413: The most agriculturally productive in the world. Loess deposits are geologically unstable by nature, and will erode very readily. Therefore, windbreaks (such as big trees and bushes) are often planted by farmers to reduce the wind erosion of loess. During mid-summer (July in the northern hemisphere), the westward-moving trade winds south of the northward-moving subtropical ridge expand northwestward from
13266-572: The movement of extratropical cyclones through the Mediterranean. Spring storm systems moving across the eastern Mediterranean Sea cause dust to carry across Egypt and the Arabian Peninsula , which are locally known as Khamsin . The Shamal is caused by cold fronts lifting dust into the atmosphere for days at a time across the Persian Gulf states. Wind dispersal of seeds, or anemochory ,
13400-409: The next. Wind engineering describes the study of the effects of the wind on the built environment, including buildings, bridges and other artificial objects. Models can provide spatial and temporal information about airflow. Spatial information can be obtained through the interpolation of data from various measurement stations, allowing for horizontal data calculation. Alternatively, profiles, such as
13534-500: The northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere. The trade winds act as the steering flow for tropical cyclones that form over the world's oceans. Trade winds also steer African dust westward across the Atlantic Ocean into the Caribbean, as well as portions of southeast North America. A monsoon is a seasonal prevailing wind that lasts for several months within tropical regions. The term
13668-558: The pressure is lower over the poles, and weakest during the summer and when pressures are higher over the poles. Together with the trade winds , the westerlies enabled a round-trip trade route for sailing ships crossing the Atlantic and Pacific Oceans, as the westerlies lead to the development of strong ocean currents on the western sides of oceans in both hemispheres through the process of western intensification . These western ocean currents transport warm, sub-tropical water polewards toward
13802-419: The pressure over the water will be lower than that of the land, establishing a land breeze, as long as an onshore wind is not strong enough to oppose it. Over elevated surfaces, heating of the ground exceeds the heating of the surrounding air at the same altitude above sea level , creating an associated thermal low over the terrain and enhancing any thermal lows that would have otherwise existed, and changing
13936-532: The range of transport and warfare, and provided a power source for mechanical work, electricity, and recreation. Wind powers the voyages of sailing ships across Earth's oceans. Hot air balloons use the wind to take short trips, and powered flight uses it to increase lift and reduce fuel consumption. Areas of wind shear caused by various weather phenomena can lead to dangerous situations for aircraft. When winds become strong, trees and human-made structures can be damaged or destroyed. Winds can shape landforms, via
14070-514: The required electrical base-load can save both fuel and total electrical generation costs. 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. Thus, the energy payback time is typically around a year. Onshore wind is an inexpensive source of electric power, cheaper than coal plants and new gas plants. According to BusinessGreen , wind turbines reached grid parity (the point at which
14204-497: The same species on the mainland. Reliance upon wind dispersal is common among many weedy or ruderal species. Unusual mechanisms of wind dispersal include tumbleweeds . A related process to anemochory is anemophily , which is the process where pollen is distributed by wind. Large families of plants are pollinated in this manner, which is favored when individuals of the dominant plant species are spaced closely together. Wind also limits tree growth. On coasts and isolated mountains,
14338-499: The spread of wildfires. Winds can disperse seeds from various plants, enabling the survival and dispersal of those plant species, as well as flying insect and bird populations. When combined with cold temperatures, the wind has a negative impact on livestock. Wind affects animals' food stores, as well as their hunting and defensive strategies. The study of wind is called anemology. Wind is caused by differences in atmospheric pressure, which are mainly due to temperature differences. When
14472-407: The surface affect the takeoff and landing phases of flight of a glider . Wind gradient can have a noticeable effect on ground launches , also known as winch launches or wire launches. If the wind gradient is significant or sudden, or both, and the pilot maintains the same pitch attitude, the indicated airspeed will increase, possibly exceeding the maximum ground launch tow speed. The pilot must adjust
14606-758: The theme "Innovation for 100% Renewable Energy" The WWEC2016 was held in Tokyo, from 31 October to 2 November 2016. WWEC2017 was held in Malmo, Sweden in June 2017. These conferences have had a far-reaching impact on the Wind Energy Policy landscape of the respective countries. China embarked upon its wind energy program after WWEC 2004 held in Beijing and today (2013) the country is leading in wind energy installations. The conference in India in 2006 had extraordinary global participation and
14740-408: 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. 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
14874-625: The transport of large amounts of energy. 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 . In 2020, wind supplied almost 1600 TWh of electricity, which was over 5% of worldwide electrical generation and about 2% of energy consumption. With over 100 GW added during 2020, mostly in China , global installed wind power capacity reached more than 730 GW. But to help meet
15008-493: The tree line is often much lower than in corresponding altitudes inland and in larger, more complex mountain systems, because strong winds reduce tree growth. High winds scour away thin soils through erosion, as well as damage limbs and twigs. When high winds knock down or uproot trees, the process is known as windthrow . This is most likely on windward slopes of mountains, with severe cases generally occurring to tree stands that are 75 years or older. Plant varieties near
15142-473: The upper layers of the ocean that elevates cool, nutrient rich waters to the surface, which leads to increased marine life. In mountainous areas, local distortion of the airflow becomes severe. Jagged terrain combines to produce unpredictable flow patterns and turbulence, such as rotors , which can be topped by lenticular clouds . Strong updrafts , downdrafts, and eddies develop as the air flows over hills and down valleys. Orographic precipitation occurs on
15276-580: The variability of wind generation. Utility-scale batteries are often used to balance hourly and shorter timescale variation, but car batteries may gain ground from the mid-2020s. 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. 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
15410-407: 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. 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
15544-692: The volatile prices of fossil fuel sources. 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
15678-412: The warm, equatorial waters and winds to the western coasts of continents, especially in the southern hemisphere because of its vast oceanic expanse. The polar easterlies, also known as Polar Hadley cells, are dry, cold prevailing winds that blow from the high-pressure areas of the polar highs at the north and South Poles towards the low-pressure areas within the Westerlies at high latitudes. Unlike
15812-502: The wind and cold, continuously alternating the members on the outside of the assembled group, which reduces heat loss by 50%. Flying insects , a subset of arthropods , are swept along by the prevailing winds, while birds follow their own course taking advantage of wind conditions, in order to either fly or glide. As such, fine line patterns within weather radar imagery, associated with converging winds, are dominated by insect returns. Bird migration, which tends to occur overnight within
15946-413: The wind circulation of the region. In areas where there is rugged topography that significantly interrupts the environmental wind flow, the wind circulation between mountains and valleys is the most important contributor to the prevailing winds. Hills and valleys substantially distort the airflow by increasing friction between the atmosphere and landmass by acting as a physical block to the flow, deflecting
16080-534: 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
16214-556: The wind parallel to the range just upstream of the topography, which is known as a barrier jet . This barrier jet can increase the low-level wind by 45%. Wind direction also changes because of the contour of the land. If there is a pass in the mountain range, winds will rush through the pass with considerable speed because of the Bernoulli principle that describes an inverse relationship between speed and pressure. The airflow can remain turbulent and erratic for some distance downwind into
16348-542: 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. 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
16482-546: The wind played a pivotal role, or the favorable winds that enabled William of Orange to invade England in 1688. During Napoleon 's Egyptian Campaign , the French soldiers had a hard time with the khamsin wind: when the storm appeared "as a blood-stint in the distant sky", the Ottomans went to take cover, while the French "did not react until it was too late, then choked and fainted in the blinding, suffocating walls of dust". During
16616-407: The wind sampling average is important, as the value of a one-minute sustained wind is typically 14% greater than a ten-minute sustained wind. A short burst of high speed wind is termed a wind gust ; one technical definition of a wind gust is: the maxima that exceed the lowest wind speed measured during a ten-minute time interval by 10 knots (19 km/h; 12 mph) for periods of seconds. A squall
16750-447: The world of mist. In Norse mythology , Njörðr is the god of the wind. There are also four dvärgar ( Norse dwarves ), named Norðri, Suðri, Austri and Vestri , and probably the four stags of Yggdrasil , personify the four winds, and parallel the four Greek wind gods. Stribog is the name of the Slavic god of winds, sky and air. He is said to be the ancestor (grandfather) of the winds of
16884-571: The world. The 6th WWEC took place in Mar del Plata, ARGENTINA in October 2007, jointly organised by Argentine Wind Energy Association (AAEE) and WWEA (see www.wwec2007.org) The 7th Special Topic "Community Power" WWEC took place in Kingston, Ontario, CANADA, in June 2008, jointly organised by Ontario Sustainable Energy Association OSEA, St Lawrence College, Kingston (SLC) and WWEA (see www.wwec2008.com) The WWEC2009
17018-714: The year 2007, has been accredited at the UNFCCC and cooperates with organizations like UNEP , UNESCO , UNDESA , the IEA and the World Bank. Since 2003, it has supported the initiative to establish an International Renewable Energy Agency IRENA which was founded in Bonn on 26 January 2009. WWEA is a founding member of International Renewable Energy Alliance (IREA), consisting of the International Hydropower Association (IHA),
17152-539: 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. 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
17286-537: Was 7.8% of world electricity. With about 100 GW added during 2021, mostly in China and the United States , global installed wind power capacity exceeded 800 GW. 32 countries generated more than a tenth of their electricity from wind power in 2023 and wind generation has nearly tripled since 2015. 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. Wind power
17420-553: Was addressed by the then President of India Honorable Dr. A P J Kalam. WWEC 2006 also included a Painting Competition having the participation of School Children from all over Delhi. This contributed to raising the level of awareness about wind energy among school-going children. The WWEC2008 in Kingston achieved the first feed-in tariff legislation in North America, the Green Energy Act of Ontario. Wind power Wind power
17554-636: Was first used in English in India, Bangladesh , Pakistan, and neighboring countries to refer to the big seasonal winds blowing from the Indian Ocean and Arabian Sea in the southwest bringing heavy rainfall to the area. Its poleward progression is accelerated by the development of a heat low over the Asian, African, and North American continents during May through July, and over Australia in December. The Westerlies or
17688-587: Was founded in 2001 as an international organization for the worldwide promotion of wind energy and has a broad societal representation and interest in wind energy utilization across the world. The founding members of WWEA are the national wind energy associations in many countries. The other members include consulting firms, scientific institutions, labs, academicians, students, wind energy enthusiasts, and equipment suppliers. There are different membership categories: WWEA has more than 600 members in more than 100 countries from all continents (as of November 2019). WWEA
17822-647: Was held in Bonn/Germany from 3 to 5 July 2012 under the theme "Community Power – Citizens' Power". (www.wwec2012.net) The WWEC2013 was held in Havana, Cuba from 3 to 5 June 2013 under the theme "Opening Doors to Caribbean Winds" The WWEC2014 was held in Shanghai, China, from 7 to 9 April 2014, under the theme "Distributed Generation: Matching supply and demand" The WWEC2015 was held in Jerusalem, from 26 to 28 October 2015, under
17956-606: Was organised together with the Korean Wind Energy Association on Jeju Island, South Korea, from 23 to 25 June 2009. The WWEC2010 was held in Istanbul/Turkey from 15 to 17 June 2010 under the theme "Large-scale integration of wind power". The WWEC2011 was held in Cairo/Egypt from 31 October to 2 November 2011 under the theme "Greening Energy: Converting Deserts into Power Houses". (www.wwec2011.net) The WWEC2012
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