A wind turbine is a device that converts kinetic energy from the wind, also called wind energy, into mechanical energy; a process known as wind power. If the mechanical energy is used to produce electricity, the device may be called a wind turbine or wind power plant. If the mechanical energy is used to drive machinery, such as for grinding grain or pumping water, the device is called a windmill or wind pump. Similarly, it may be referred to as a wind charger when used for charging batteries.
The result of over a millennium of windmill development and modern engineering, today's wind turbines are manufactured in a wide range of vertical and horizontal axis types. The smallest turbines are used for applications such as battery charging or auxiliary power on boats; while large grid-connected arrays of turbines are becoming an increasingly important source of wind power-produced commercial electricity.
Windmills were used in Persia (present-day Iran) as early as 200 B.C. The windwheel of Heron of Alexandria marks one of the first known instances of wind powering a machine in history. However, the first known practical windmills were built in Sistan, a region between Afghanistan and Iran, from the 7th century. These "Panemone" were vertical axle windmills, which had long vertical driveshafts with rectangular blades. Made of six to twelve sails covered in reed matting or cloth material, these windmills were used to grind grain or draw up water, and were used in the gristmilling and sugarcane industries.
Windmills first appeared in Europe during the middle ages. The first historical records of their use in England date to the 11th or 12th centuries and there are reports of German crusaders taking their windmill-making skills to Syria around 1190. By the 14th century, Dutch windmills were in use to drain areas of the Rhine delta.
The first electricity-generating wind turbine was a battery charging machine installed in July 1887 by Scottish academic James Blyth to light his holiday home in Marykirk, Scotland. Some months later American inventor Charles F Brush built the first automatically operated wind turbine for electricity production in Cleveland, Ohio. Although Blyth's turbine was considered uneconomical in the United Kingdom electricity generation by wind turbines was more cost effective in countries with widely scattered populations.
In Denmark by 1900, there were about 2500 windmills for mechanical loads such as pumps and mills, producing an estimated combined peak power of about 30 MW. The largest machines were on 24-metre (79 ft) towers with four-bladed 23-metre (75 ft) diameter rotors. By 1908 there were 72 wind-driven electric generators operating in the US from 5 kW to 25 kW. Around the time of World War I, American windmill makers were producing 100,000 farm windmills each year, mostly for water-pumping. By the 1930s, wind generators for electricity were common on farms, mostly in the United States where distribution systems had not yet been installed. In this period, high-tensile steel was cheap, and the generators were placed atop prefabricated open steel lattice towers.
A forerunner of modern horizontal-axis wind generators was in service at Yalta, Soviet Ukraine in the USSR in 1931. This was a 100 kW generator on a 30-metre (98 ft) tower, connected to the local 6.3 kV distribution system. It was reported to have an annual capacity factor of 32 per cent, not much different from current wind machines. In the fall of 1941, the first megawatt-class wind turbine was synchronized to a utility grid in Vermont. The Smith-Putnam wind turbine only ran for 1,100 hours before suffering a critical failure. The unit was not repaired because of shortage of materials during the war.
As of 2012, Danish company Vestas is the world's biggest wind-turbine manufacturer.
A quantitative measure of the wind energy available at any location is called the Wind Power Density (WPD) It is a calculation of the mean annual power available per square meter of swept area of a turbine, and is tabulated for different heights above ground. Calculation of wind power density includes the effect of wind velocity and air density. Color-coded maps are prepared for a particular area described, for example, as "Mean Annual Power Density at 50 Metres". In the United States, the results of the above calculation are included in an index developed by the National Renewable Energy Laboratory and referred to as "NREL CLASS". The larger the WPD calculation, the higher it is rated by class. Classes range from Class 1 (200 watts per square metre or less at 50 m altitude) to Class 7 (800 to 2000 watts per square m). Commercial wind farms generally are sited in Class 3 or higher areas, although isolated points in an otherwise Class 1 area may be practical to exploit.
Wind turbines are classified by the wind speed they are designed for, from class I to class IV, with A or B referring to the turbulence.
|Class||Avg Wind Speed (m/s)||Turbulence|
Theoretical power captured by a wind turbine
Total wind power could be captured only if the wind velocity is reduced to zero. In a realistic wind turbine this is impossible, as the captured air must also leave the turbine. A relation between the input and output wind velocity must be considered. Using the concept of streamtube, the maximal achievable extraction of wind power by a wind turbine is 59% of the total theoretical wind power (see: Betz' law).
Practical wind turbine power
Further inefficiencies, such as rotor blade friction and drag, gearbox losses, generator and converter losses, reduce the power delivered by a wind turbine. The basic relation that the turbine power is (approximately) proportional to the third power of velocity remains.
Wind turbines can rotate about either a horizontal or a vertical axis, the former being both older and more common.
Horizontal-axis wind turbines (HAWT) have the main rotor shaft and electrical generator at the top of a tower, and must be pointed into the wind. Small turbines are pointed by a simple wind vane, while large turbines generally use a wind sensor coupled with a servo motor. Most have a gearbox, which turns the slow rotation of the blades into a quicker rotation that is more suitable to drive an electrical generator.
Since a tower produces turbulence behind it, the turbine is usually positioned upwind of its supporting tower. Turbine blades are made stiff to prevent the blades from being pushed into the tower by high winds. Additionally, the blades are placed a considerable distance in front of the tower and are sometimes tilted forward into the wind a small amount.
Downwind machines have been built, despite the problem of turbulence (mast wake), because they don't need an additional mechanism for keeping them in line with the wind, and because in high winds the blades can be allowed to bend which reduces their swept area and thus their wind resistance. Since cyclical (that is repetitive) turbulence may lead to fatigue failures, most HAWTs are of upwind design.
Turbines used in wind farms for commercial production of electric power are usually three-bladed and pointed into the wind by computer-controlled motors. These have high tip speeds of over 320 km/h (200 mph), high efficiency, and low torque ripple, which contribute to good reliability. The blades are usually colored white for daytime visibility by aircraft and range in length from 20 to 40 metres (66 to 130 ft) or more. The tubular steel towers range from 60 to 90 metres (200 to 300 ft) tall. The blades rotate at 10 to 22 revolutions per minute. At 22 rotations per minute the tip speed exceeds 90 metres per second (300 ft/s). A gear box is commonly used for stepping up the speed of the generator, although designs may also use direct drive of an annular generator. Some models operate at constant speed, but more energy can be collected by variable-speed turbines which use a solid-state power converter to interface to the transmission system. All turbines are equipped with protective features to avoid damage at high wind speeds, by feathering the blades into the wind which ceases their rotation, supplemented by brakes.
Vertical axis design
Vertical-axis wind turbines (or VAWTs) have the main rotor shaft arranged vertically. Key advantages of this arrangement are that the turbine does not need to be pointed into the wind to be effective. This is an advantage on sites where the wind direction is highly variable, for example when integrated into buildings. The key disadvantages include the low rotational speed with the consequential higher torque and hence higher cost of the drive train, the inherently lower power coefficient, the 360 degree rotation of the aerofoil within the wind flow during each cycle and hence the highly dynamic loading on the blade, the pulsating torque generated by some rotor designs on the drive train, and the difficulty of modelling the wind flow accurately and hence the challenges of analysing and designing the rotor prior to fabricating a prototype.
With a vertical axis, the generator and gearbox can be placed near the ground, using a direct drive from the rotor assembly to the ground-based gearbox, hence improving accessibility for maintenance.
When a turbine is mounted on a rooftop, the building generally redirects wind over the roof and this can double the wind speed at the turbine. If the height of the rooftop mounted turbine tower is approximately 50% of the building height, this is near the optimum for maximum wind energy and minimum wind turbulence. It should be borne in mind that wind speeds within the built environment are generally much lower than at exposed rural sites, noise may be a concern and an existing structure may not adequately resist the additional stress.
Another type of vertical axis is the Parallel turbine similar to the crossflow fan or centrifugal fan it uses the ground effect. Vertical axis turbines of this type have been tried for many years: a large unit producing up to 10 kW was built by Israeli wind pioneer Bruce Brill in 1980s: the device is mentioned in Dr. Moshe Dan Hirsch's 1990 report, which decided the Israeli energy department investments and support in the next 20 years. The Magenn WindKite blimp uses this configuration as well, chosen because of the ease of running.
Design and construction
Wind turbines are designed to exploit the wind energy that exists at a location. Aerodynamic modelling is used to determine the optimum tower height, control systems, number of blades and blade shape.
Wind turbines convert wind energy to electricity for distribution. Conventional horizontal axis turbines can be divided into three components:
- The rotor component, which is approximately 20% of the wind turbine cost, includes the blades for converting wind energy to low speed rotational energy.
- The generator component, which is approximately 34% of the wind turbine cost, includes the electrical generator, the control electronics, and most likely a gearbox (e.g. planetary gearbox, adjustable-speed drive or continuously variable transmission) component for converting the low speed incoming rotation to high speed rotation suitable for generating electricity.
- The structural support component, which is approximately 15% of the wind turbine cost, includes the tower and rotor yaw mechanism.
A 1.5 MW wind turbine of a type frequently seen in the United States has a tower 80 metres (260 ft) high. The rotor assembly (blades and hub) weighs 48,000 pounds (22,000 kg). The nacelle, which contains the generator component, weighs 115,000 pounds (52,000 kg). The concrete base for the tower is constructed using 58,000 pounds (26,000 kg) of reinforcing steel and contains 250 cubic yards (190 m3) of concrete. The base is 50 ft (15 m) in diameter and 8 ft (2.4 m) thick near the center.
One E-66 wind turbine at Windpark Holtriem, Germany, carries an observation deck, open for visitors. Another turbine of the same type, with an observation deck, is located in Swaffham, England. Airborne wind turbines have been investigated many times but have yet to produce significant energy. Conceptually, wind turbines may also be used in conjunction with a large vertical solar updraft tower to extract the energy due to air heated by the sun.
The ram air turbine is a specialist form of small turbine that is fitted to some aircraft. When deployed, the RAT is spun by the airstream going past the aircraft and can provide power for the most essential systems if there is a loss of all on–board electrical power.
Wind turbines on public display
A few localities have exploited the attention-getting nature of wind turbines by placing them on public display, either with visitor centers around their bases, or with viewing areas farther away. The wind turbines themselves are generally of conventional horizontal-axis, three-bladed design, and generate power to feed electrical grids, but they also serve the unconventional roles of technology demonstration, public relations, and education.
- Australia: Blayney Wind Farm, New South Wales has a viewing area and interpretive centre; Wattle Point Wind Farm, South Australia has an information centre
- Canada: OPG 7 commemorative turbine is a Vestas V80-1.8MW wind turbine on the site of the Pickering Nuclear Generating Station; Toronto Hydro - WindShare features a Lagerwey Wind model LW 52 wind turbine at Exhibition Place
- China: Inner Mongolia's Huitengxile Wind Farm has 14 visitor centers to accommodate wind power tourists to the remote region
- Hong Kong: Lamma Winds has a single Nordex N50/800 kW model with a rotor diameter of 50m and a nameplate capacity of 800 kW
- New Zealand: Brooklyn, Wellington, New Zealand has a 230 kW wind turbine
- United Kingdom: Ecotech Centre, Swaffham, Norfolk; Green Park Business Park has an Enercon E-70 2 MW wind turbine adjacent to the M4 motorway, billed as the UK's most visible turbine; Renewable Energy Systems has a Vestas V29 225 kW wind turbine visible from the M25 motorway at its headquarters at Beaufort Court, Kings Langley, Hertfordshire; Scroby Sands wind farm has a visitor center at Great Yarmouth open during the tourist season (May–October); Scout Moor Wind Farm "has become a real tourist attraction" since its 2008 opening; Whitelee Wind Farm near Glasgow has become the first wind energy project in Scotland to join the Association of Scottish Visitor Attractions (ASVA).
- United States: Dorchester, Massachusetts - Local 103 of the International Brotherhood of Electrical Workers installed the first commercial-scale wind turbine within the City of Boston, a 100 kW unit from Fuhrlaender on a 35-meter tower with rotor diameter of 21 meters, visible from the John F. Kennedy Library; The Great Lakes Science Center in Cleveland, Ohio has a reconditioned Vestas V27 wind turbine with a nameplate capacity of 225 kW; Great River Energy's headquarters in Maple Grove, Minnesota has a NEG Micon M700 wind turbine, visible from Interstate 94; Laurel, New York has a Northern Power Systems 100 kW turbine at the Half Hollow Nursery and private tours of the operating turbine are provided by Eastern Energy Systems Inc. of Mattituck, New York; Lubbock, Texas has a Vestas V47 at the American Wind Power Center; McKinney, Texas has a Wal-Mart store with several sustainability features, including two wind turbines manufactured by Bergey Windpower, of 1 kW and 50 kW nameplate capacity respectively; Sweetwater, Texas has a 2 MW 60 Hz DeWind D8.2 prototype wind turbine for training students in the Texas State Technical College wind energy program
Small wind turbines
Small wind turbines may be used for a variety of applications including on- or off-grid residences, telecom towers, offshore platforms, rural schools and clinics, remote monitoring and other purposes that require energy where there is no electric grid, or where the grid is unstable. Small wind turbines may be as small as a fifty-watt generator for boat or caravan use. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) defines small wind turbines as those smaller than or equal to 100 kilowatts. Small units often have direct drive generators, direct current output, aeroelastic blades, lifetime bearings and use a vane to point into the wind.
Larger, more costly turbines generally have geared power trains, alternating current output, flaps and are actively pointed into the wind. Direct drive generators and aeroelastic blades for large wind turbines are being researched.
Wind turbine spacing
On most horizontal windturbine farms, a spacing of about 6-10 times the rotor diameter is often upheld. However, for large wind farms distances of about 15 rotor diameters should be more economically optimal, taking into account typical wind turbine and land costs. This conclusion has been reached by research conducted by Charles Meneveau of the Johns Hopkins University, and Johan Meyers of Leuven University in Belgium, based on computer simulations that take into account the detailed interactions among wind turbines (wakes) as well as with the entire turbulent atmospheric boundary layer. Moreover, recent research by John Dabiri of Caltech suggests that vertical wind turbines may be placed much more closely together so long as an alternating pattern of rotation is created allowing blades of neighbouring turbines to move in the same direction as they approach one another.
Several cases occurred where the housings of wind turbines caught fire. As housings are normally out of the range of standard fire extinguishing equipment, it is nearly impossible to extinguish such fires on older turbine units which lack fire suppression systems. In several cases one or more blades were damaged or torn away. In 2010 70 mph (110 km/h; 61 kn) storm winds damaged some blades, prompting blade removal and inspection of all 25 wind turbines in Campo Indian Reservation in the US State of California. Several wind turbines also collapsed.
|Place||Date||Type||Nacelle height||Rotor dia.||Year built||Reason||Damage and casualties|
|Ellenstedt, Germany||October 19, 2002|||
|Schneebergerhof, Germany||December 20, 2003||Vestas V80||80 m|||
|Wasco, Oregon, USA||August 25, 2007||Siemens||Human error: turbine restarted while blades were locked in maximum wind-resistance mode||1 worker killed, 1 injured|
|Stobart Mill, UK||December 30, 2007||Vestas||1982|||
|Hornslet, Denmark||February 22, 2008||Nordtank NKT 600-180||44.5 m||43 m||1996||Brake failure|
|Searsburg, Vermont, USA||October 16, 2008||Zond Z-P40-FS||1997||Rotor blade collided with tower during strong wind and destroyed it|
|Altona, New York, USA||March 6, 2009||GE Energy 1.5MW||Lightning likely |
|Fenner, New York, USA||December 27, 2009||GE Energy 1.5 MW|||
|Kirtorf, Germany||June 19, 2011||DeWind D-6||68.5 m||62 m||2001|
|Ayrshire, Scotland||December 8, 2011||Vestas V80 2MW|||
- Largest capacity
- The Enercon E-126 has a rated capacity of 7.58 MW, has an overall height of 198 m (650 ft), a diameter of 126 m (413 ft), and is the world's largest-capacity wind turbine since its introduction in 2007. At least five companies are working on the development of a 10 MW turbine.
- Largest swept area
- The turbine with the largest swept area is the Siemens SWT-6.0-154, with a diameter of 154 m, giving a total sweep of 18,600 m2.
- The tallest wind turbines are two standing in Paproć, Poland, 210 meters tall, also constructed by Fuhrlaender in late 2012. Their axis have the same height as previous tallest turbine, Fuhrländer Wind Turbine Laasow, that is 160 meters, but their rotors reach 210 against the Laasow's 205 meters. Those three turbines are the only ones in the world taller than 200 meters.
- Largest vertical-axis
- Le Nordais wind farm in Cap-Chat, Quebec has a vertical axis wind turbine (VAWT) named Éole, which is the world's largest at 110 m. It has a nameplate capacity of 3.8 MW.
- Most southerly
- The turbines currently operating closest to the South Pole are three Enercon E-33 in Antarctica, powering New Zealand's Scott Base and the United States' McMurdo Station since December 2009 although a modified HR3 turbine from Northern Power Systems operated at the Amundsen-Scott South Pole Station in 1997 and 1998. In March 2010 CITEDEF designed, built and installed a wind turbine in Argentine Marambio Base.
- Most productive
- Four turbines at Rønland wind farm in Denmark share the record for the most productive wind turbines, with each having generated 63.2 GWh by June 2010.
- The world's highest-situated wind turbine is made by DeWind installed by the Seawind Group and located in the Andes, Argentina around 4,100 meters (13,500 ft) above sea level. The site uses a type D8.2 - 2000 kW / 50 Hz turbine. This turbine has a new drive train concept with a special torque converter (WinDrive) made by Voith and a synchronous generator. The WKA was put into operation in December 2007 and has supplied the Veladero mine of Barrick Gold with electricity since then.
- Largest floating wind turbine
- The world's largest—and also the first operational deep-water large-capacity—floating wind turbine is the 2.3 MW Hywind currently operating 10 kilometers (6.2 mi) offshore in 220-meter-deep water, southwest of Karmøy, Norway. The turbine began operating in September 2009 and utilizes a Siemens 2.3 MW turbine.
Horizontal axis wind turbines
A list of the different models of wind turbines from the top 10 wind turbine manufacturers by market share:
|MW||Name||Manufacturer||Market date||Offshore||Swept area m2||Rotor diameter
|8.0 MW||V164-8.0 MW||Vestas||2015 Q1||x||21,124||164||105||x|
|6.0 MW||SWT-6.0-154||Siemens Wind Power||2012||both||18,600||154||Site-specific||-|
|5.0 MW||G128-5.0 MW||Gamesa||2013||x||12,868||128||80-94||x|
|4.5 MW||G136-4.5 MW||Gamesa||2011||-||14,527||136||120||x|
|4.5 MW||G128-4.5 MW||Gamesa||2012||-||12,868||128||81, 120, 140||x|
|4.1 MW||4.1-113||GE Energy||x||9,940||113||-|
|3.6 MW||SWT-3.6-120||Siemens Wind Power||2010||-||11,300||120||90||x|
|3.6 MW||SWT-3.6-107||Siemens Wind Power||2004||both||9,000||107||80||x|
|3.05 MW||E-101||Enercon||?||-||8,012||101||99, 135, 149||-|
|3.0 MW||UP100DD||Guodian United Power||?||-||100||-|
|3.0 MW||UP100DF||Guodian United Power||?||-||100||x|
|3.0 MW||SWT-3.0-113||Siemens Wind Power||?||-||10,000||113||79.5-142.5||-|
|3.0 MW||SWT-3.0-108||Siemens Wind Power||?||-||9,150||108||79.5-99.5||-|
|3.0 MW||SWT-3.0-101||Siemens Wind Power||?||-||8,000||101||74.5-99.5||-|
|3.0 MW||V112-3.0 MW||Vestas||?||-||9,852||112||84, 94, 119||x|
|3.0 MW||V112-3.0 MW Offshore||Vestas||?||x||9,852||112||site specific||x|
|3.0 MW||V90-3 MW||Vestas||2003||-||6,362||90||80, 90, 105||x|
|3.0 MW||V90-3.0 MW Offshore||Vestas||2003||x||6,362||90||site specific||x|
|3.0 MW||E-82 E3, E4||Enercon||?||-||5,281||82||78, 85, 98, 108, 138||-|
|3.0 MW||SCD 3.0 MW||Ming Yang||?||-||6,644, 7,850||92, 100, 108||75, 85, 90, 100||x|
|2.75 MW||2.75-103||GE Energy||?||-||103||85, 98.3||x|
|2.75 MW||2.75-100||GE Energy||?||-||100||85, 98.3||x|
|2.6 MW||V100-2.6 MW||Vestas||?||-||7,854||100||x|
|2.5 MW||GW 109||Goldwind||?||-||9,399||109||100||-|
|2.5 MW||GW 106||Goldwind||?||-||8,824||106||100||-|
|2.5 MW||GW 100||Goldwind||?||-||7,823||100||100||-|
|2.5 MW||GW 90||Goldwind||?||-||6,362||90||80||-|
|2.5 MW||SCD 2.5 MW||Ming Yang||?||-||6,644, 7,850||92, 100, 108||75, 85, 90, 100||x|
|2.35 MW||E-92||Enercon||?||-||6,648||92||85, 98, 104, 108, 138||-|
|2.3 MW||E-82 E2||Enercon||?||-||5,281||82||78, 85, 98, 108, 138||-|
|2.3 MW||E-70||Enercon||?||-||3,959||71||57, 64, 74, 85, 98, 113||-|
|2.3 MW||SWT-2.3-113||Siemens Wind Power||?||-||10,000||113||99.5||-|
|2.3 MW||SWT-2.3-108||Siemens Wind Power||?||-||9,144||108||80||x|
|2.3 MW||SWT-2.3-101||Siemens Wind Power||?||-||8,000||101||80||x|
|2.3 MW||SWT-2.3-93||Siemens Wind Power||?||-||6,800||93||80||x|
|2.3 MW||SWT-2.3-82 VS||Siemens Wind Power||?||-||5,300||82.4||80||x|
|2.25 MW||S88 MARK II DFIG 2.25 MW||Suzlon||2011||-||6,082||88||80||x|
|2.1 MW||S9X (S95, S97)||Suzlon||?||-||7,085, 7,386||95, 97||80, 90, 100||x|
|2.1 MW||S88-2.1 MW||Suzlon||?||-||6,082||88||80||x|
|2.0 MW||E-82 E2||Enercon||?||-||5,281||82||78, 85, 98, 108, 138||-|
|2.0 MW||G114-2.0 MW||Gamesa||2013||-||10,207||114||93, 120, 140||x|
|2.0 MW||G97-2.0 MW||Gamesa||2010||-||7,390||97||78, 90||x|
|2.0 MW||G90-2.0 MW||Gamesa||2005||-||6,362||90||67, 78, 100||x|
|2.0 MW||G87-2.0 MW||Gamesa||2004||-||5,945||87||67, 78, 90, 100||x|
|2.0 MW||G80-2.0 MW||Gamesa||2003||-||5,027||80||60, 67, 78, 100||x|
|2.0 MW||UP96||Guodian United Power||?||-||96.4||x|
|1.8/2.0 MW||V100-1.8/2.0 MW||Vestas||?||-||7,854||100||80, 95||x|
|1.8 MW||V100-1.8 MW||Vestas||?||-||100|
|1.8/2.0 MW||V90-1.8/2.0 MW||Vestas||?||-||6,362||90||80-125||x|
|2.0 MW||V80-2.0 MW||Vestas||?||-||5,027||80||60-100||x|
|1.6 MW||1.6-82.5||GE Energy||2008||-||5,346||82.5||65, 80, 100||x|
|1.5 MW||1.5-77||GE Energy||2004||-||4,657||77||65, 80||x|
|1.5 MW||1.5s||GE Energy||?||-||3,904||70.5||64.7||x|
|1.5 MW||1.5i||GE Energy||1996||-||65||x|
|1.5 MW||GW 87||Goldwind||?||-||5,890||87||70, 75, 85, 100||-|
|1.5 MW||GW 82||Goldwind||?||-||5,324||82||70, 75, 85, 100||-|
|1.5 MW||GW 77||Goldwind||?||-||4,654||77||61.5, 85, 100||-|
|1.5 MW||GW 70||Goldwind||?||-||3,850||70||65, 85||-|
|1.5 MW||UP86||Guodian United Power||?||-||86.086||x|
|1.5 MW||UP82||Guodian United Power||?||-||82.76||x|
|1.5 MW||UP77||Guodian United Power||?||-||77.36||x|
|1.5 MW||MY 1.5s||Ming Yang||?||-||5,320||82.6||65, 70, 75, 80||x|
|1.5 MW||MY 1.5se||Ming Yang||?||-||4,368||77.1||65, 70, 75, 80||x|
|1.5 MW||MY 1.5Sh||Ming Yang||?||-||5,320||82.6||65, 70, 75, 80||x|
|1.5 MW||MY 1.5Su||Ming Yang||?||-||4,368/5,320||77.1/82.6||65, 70, 75, 80||x|
|1.5 MW||S82-1.5 MW||Suzlon||?||-||5,281||82||78.5||x|
|1.5 MW||SL1500/70,77,82||Sinovel||?||-||3,892.5, 4,657, 5,398||70.4, 77.4, 82.9||65-100||x|
|1.25 MW||S66-1.25 MW||Suzlon||?||-||3,421||66||74.5||x|
|1.25 MW||S66-1.25 MW||Suzlon||?||-||3,421||66||74.5||x|
|1.25 MW||S64-1.25 MW||Suzlon||?||-||3,217||64||74.5||x|
|0.9 MW||E-44||Enercon||?||-||1,521||44||45, 55||-|
|0.85 MW||G58-0.85 MW||Gamesa||?||-||2,682||58||44, 55, 65, 74||x|
|0.85 MW||G52-0.85 MW||Gamesa||?||-||2,214||52||44, 55, 65||x|
|0.8 MW||E-53||Enercon||?||-||2,198||52.9||60, 73||-|
|0.8 MW||E-48||Enercon||?||-||1,810||48||50, 55, 60, 76||-|
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- [dead link]
- Products & Services
- Technical Specs of Common Wind Turbine Models [AWEO.org]
- Windspeed in the city - reality versus the DTI database
- Modular wind energy device - Brill, Bruce I
- ZF Friedrichshafen AG
- djtreal.com - de beste bron van informatie over djtreal. Deze website is te koop!
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- Technical specifications
- Siemens 6.0 MW Offshore Wind Turbine
- Gamesa 5.0 MW
- Gamesa launches its new G136-4.5 MW turbine, designed for low-wind sites
- Gamesa G136-4.5 MW
- Gamesa 4.5 MW
- 4.1-113 Offshore Wind Turbine
- Technical Parameters
- Siemens 3.0 MW Direct Drive Wind Turbines
- V112-3.0 MW
- V112-3.0 MW Offshore
- Mingyang Wind Power
- SL3000 Series Wind Turbine
- GE's 2.75 MW Wind Turbines
- GW 2.5 PMDD Wind Turbine
- E-70 / 2,300 kW
- Siemens SWT-2.3-113
- Siemens Wind Turbine SWT-2.3-108
- Wind Turbine SWT-2.3-101
- Wind Turbine SWT-2.3-93
- S88 MARK II DFIG 2.25 MW
- Introducing the S9X
- S88-2.1 MW
- E-82 E2 / 2,000 kW
- Gamesa launches a new turbine, the G114-2.0 MW: maximum returns for low-wind sites
- Gamesa maintained profitability and sound financial position in a situation of economic weakness and regulatory uncertainty
- Gamesa G97-2.0 MW IIIA
- Gamesa supplies 9 latest generation wind turbines to wind farms in Albacete
- Gamesa G87-2.0 MW
- Gamesa G80-2.0 MW
- Vestas 2MW
- GE's 1.6 MW Wind Turbines
- GE 1.5-77 Wind Turbines
- GE 1.5 MW Wind Turbine
- GW 1.5 PMDD Wind Turbine
- Mingyang Wind Power
- S82-1.5 MW
- Eternal Power from Sinovel
- S66-1.25 MW
- S64-1.25 MW
- Enercon Product Overview
- Gamesa G58-850 kW
- Gamesa G52-850 kW
- E-53 / 800 kW
- E-48 / 800 kW
- S52-600 kW
- Tony Burton, David Sharpe, Nick Jenkins, Ervin Bossanyi: Wind Energy Handbook, John Wiley & Sons, 1st edition (2001), ISBN 0-471-48997-2
- Darrell, Dodge, Early History Through 1875, TeloNet Web Development, Copyright 1996–2001
- David, Macaulay, New Way Things Work, Houghton Mifflin Company, Boston, Copyright 1994–1999, pg.41-42
- Erich Hau Wind turbines: fundamentals, technologies, application, economics Birkhäuser, 2006 ISBN 3-540-24240-6 (preview on Google Books)
- David Spera (ed,) Wind Turbine Technology: Fundamental Concepts in Wind Turbine Engineering, Second Edition (2009), ASME Press, ISBN #: 9780791802601
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