How Do Wind Turbines Work?

How Do Wind Turbines Work?
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author: Wikimedia Commons

C O N T E N T S:


  • Wind turbine design is the process of defining the form and specifications of a wind turbine to extract energy from the wind. 1 2 A wind turbine installation consists of the necessary systems needed to capture the wind’s energy, point the turbine into the wind, convert mechanical rotation into electrical power, and other systems to start, stop, and control the turbine.(More…)
  • Next time when you hear someone complaining about how wind turbines are causing noise and aesthetic pollution, with a better understanding of how do wind turbines work, you can explain convincingly wind power sceptics, who may not have a good understanding of green energy, about how wind turbines function to generate alternative clean power from wind, which is one of the fastest-growing renewable resources in the world.(More…)
  • The blades work by generating lift and drag due to their difference in shapes when the wind blows over them, like an airplane.(More…)
  • There is a simple rule of thumb for wind turbines: The bigger the blades — or rotor diameter — the more power it can generate.(More…)
  • Their shrouded turbine works by creating a rapid-mixing vortex when wind hits it, and has fins that allow it to turn into the wind for maximum energy.(More…)
  • The power produced by wind has taken the energy industry by storm in recent years, but there is still much work to be done to fully leverage this renewable resource.(More…)
  • Have an in depth understanding of the different components of the wind turbine including the electrical pitch system, computerized control system, and the power conversion unit as well as knowledge and understanding of OEM approved mechanical maintenance methods and practices.(More…)
  • Wind energy has been in use for quite a long time now, with windmills being used effectively to do mechanical work.(More…)
  • It appears wind power and solar power are here to stay, even as President Donald Trump’s administration works to.(More…)


  • The turbine’s rotation can be kept at a safe speed in faster winds while maintaining (nominal) power output.(More…)
  • The energy in the wind turns two or three propeller-like blades around a rotor (as shown in the picture).(More…)
  • Unlike other methods of harnessing energy, wind does not harm the environment and is recognized as one of the cleanest and safest methods of generating renewable electricity.(More…)
  • VAWTs have been proven to generate more power per unit land area than HAWTs; this is because micrositing of VAWTs can be done in a way such that there is a better use of the wind rich land.(More…)



Wind turbine design is the process of defining the form and specifications of a wind turbine to extract energy from the wind. 1 2 A wind turbine installation consists of the necessary systems needed to capture the wind’s energy, point the turbine into the wind, convert mechanical rotation into electrical power, and other systems to start, stop, and control the turbine. [1] Energy harnessed by wind turbines is intermittent, and is not a “dispatchable” source of power; its availability is based on whether the wind is blowing, not whether electricity is needed. [2] Older style wind generators rotate at a constant speed, to match power line frequency, which allowed the use of less costly induction generators. citation needed Newer wind turbines often turn at whatever speed generates electricity most efficiently. [1] The rotor, which is approximately 20% of the wind turbine cost, includes the blades for converting wind energy to low speed rotational energy. [2] Older style wind turbines were designed with heavier steel blades, which have higher inertia, and rotated at speeds governed by the AC frequency of the power lines. [1] New wind turbine designs push power generation from the single megawatt range to upwards of 10 megawatts using larger and larger blades. [1] The shape and dimensions of the blades of the wind turbine are determined by the aerodynamic performance required to efficiently extract energy from the wind, and by the strength required to resist the forces on the blade. [1] 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. [2] In December 2011, the U.S. Department of Energy published a report stating critical shortage of rare-earth elements such as neodymium used in large quantities for permanent magnets in gearless wind turbines. 20 China produces more than 95% of rare-earth elements, while Hitachi holds more than 600 patents covering Neodymium magnets. [1] Operating closer to their optimal tip speed ratio during energetic gusts of wind allows wind turbines to improve energy capture from sudden gusts that are typical in urban settings. [1] Use of aluminum and composite materials in their blades has contributed to low rotational inertia, which means that newer wind turbines can accelerate quickly if the winds pick up, keeping the tip speed ratio more nearly constant. [1] Based on a study carried out by the European Wind Energy Association, in the year 2010 alone, between 110 and 140 kilotons of composites were consumed by the wind turbine industry for manufacturing blades. 51 The majority of the blade material will eventually end up as waste, and in order to accommodate this level of composite waste, the only option is recycling. [1] How? Wind causes the huge blades of a wind turbine to rotate, and this initiates the spinning of a shaft that is connected to a generator to convert kinetic energy into electricity. [3] Wind turbines convert the kinetic energy in the wind into mechanical power which can be converted by a generator into electricity – to power homes, businesses, schools, and the like. [3] With different control schemes a wind turbine with a permanent magnet synchronous generator can provide or consume reactive power. [1] Wind turbine components: 1- Foundation, 2- Connection to the electric grid, 3- Tower, 4-Access ladder, 5- Wind orientation control (Yaw control), 6- Nacelle, 7- Generator, 8- Anemometer, 9- Electric or Mechanical Brake, 10- Gearbox, 11- Rotor blade, 12- Blade pitch control, 13- Rotor hub. [1] For large, commercial size horizontal-axis wind turbines, the electrical generator 15 is mounted in a nacelle at the top of a tower, behind the hub of the turbine rotor. [1] These turbines have the main rotor shaft and electrical generator at the top of a tower, and must be pointed into the wind. [2] Despite these advantages, upwind designs are preferred, because the change in loading from the wind as each blade passes behind the supporting tower can cause damage to the turbine. [2] By minimizing the yaw angle (the misalignment between wind and turbine pointing direction), the power output is maximized and non-symmetrical loads minimized. [1] Larger, more costly turbines generally have geared power trains, alternating current output, flaps and are actively pointed into the wind. [2]

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. 59 The wind turbines 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. [2] Further design questions arise when integrating wind turbines into electrical power grids. [1]

Wind turbine design is a careful balance of cost, energy output, and fatigue life. [2] Over 1,500 tons of carbon dioxide per year can be eliminated by using a one megawatt turbine instead of one megawatt of energy from a fossil fuel. 74 Being environmentally friendly and green is a large advantage of wind turbines. [2] The flow patterns of wind, also known as motion energy, can be used to generate electricity when “harvested? by modern wind turbines. [3] The smallest having power production less than 10kW are used in homes, farms and remote applications whereas intermediate wind turbines (10-250kW ) are useful for village power, hybrid systems and distributed power. [1] The speed at which a wind turbine rotates must be controlled for efficient power generation and to keep the turbine components within designed speed and torque limits. [1] A wind turbine is designed to produce power over a range of wind speeds. The cut-in speed is around 3-4m/s for most turbines, and cut-out at 25m/s. 3 If the rated wind speed is exceeded the power has to be limited. [1] A fixed-speed HAWT (Horizontal Axis Wind Turbine) inherently increases its angle of attack at higher wind speed as the blades speed up. [1] In conventional wind turbines, the blades spin a shaft that is connected through a gearbox to the generator. [1] Step-up gearboxes are being increasingly replaced with variable speed generators, increasing the demand for magnetic materials in wind turbines. 46 In particular, this would require an increased supply of the rare earth metal neodymium. [2] The generator, which is approximately 34% of the wind turbine cost, includes the electrical generator, 38 39 the control electronics, and most likely a gear box (e.g. planetary gear box ), 40 adjustable-speed drive or continuously variable transmission 41 component for converting the low-speed incoming rotation to high-speed rotation suitable for generating electricity. [2] Usually the rotational speed of the wind turbine is slower than the equivalent rotation speed of the electrical network: typical rotation speeds for wind generators are 5-20 rpm while a directly connected machine will have an electrical speed between 750 and 3600 rpm. [1] In that way the wind turbine will not consume reactive power, which is the most common problem with wind turbines that use induction machines. [1] Below some minimum wind velocity, no useful power output can be produced from wind turbine. [1] One of the predominant ways wind turbines have gained performance is by increasing rotor diameters, and thus blade length. [2] Large three-bladed horizontal-axis wind turbines (HAWT), with the blades upwind of the tower produce the overwhelming majority of windpower in the world today. [2] Wind turbines developed over the last 50 years have almost universally used either two or three blades. [1] Currently, digital image correlation and stereophotogrammetry are used to measure dynamics of wind turbine blades. [2] Environmental impact of wind power includes effect on wildlife, but can be mitigated if proper monitoring and mitigation strategies are implemented. 76 Thousands of birds, including rare species, have been killed by the blades of wind turbines, 77 though wind turbines contribute relatively insignificantly to anthropogenic avian mortality. [2] While aligning the wind turbine to changes in wind direction (yawing), each blade experiences a cyclic load at its root end depending on blade position. [1] Materials selection strategy and surface treatment of polymer composites for wind turbine blades fabrication. [1] Offshore wind turbines are built up to 8MW today and have a blade length up to 80 meters (260ft). [2] In his book Machinae Novae (1595) he described vertical axis wind turbines with curved or V-shaped blades. [2] In Germany, wind turbine blades are commercially recycled as part of an alternative fuel mix for a cement factory. [2] Wind turbines can be very large, reaching over 140 metres (460ft) tall and with blades 55 metres (60yd) long, 75 and people have often complained about their visual impact. [2] One major problem in designing wind turbines is getting the blades to stall or furl quickly enough should a gust of wind cause sudden acceleration. [1] The majority of current commercialized wind turbine blades are made from fiber-reinforced polymers (FRPs), which are composites consisting of a polymer matrix and fibers. [1] Fiberglass -reinforced epoxy blades of Siemens SWT-2.3-101 wind turbines. [1] Development of multifunctional nanocomposite coatings for wind turbine blades. [1] Wind turbines provide a clean energy source, emitting no greenhouse gases and no waste product. [2] If the low-temperature interval is combined with a low-wind condition, the wind turbine will require an external supply of power, equivalent to a few percent of its rated power, for internal heating. [1] The use of lighter materials in the tower could greatly reduce the overall transport and construction cost of wind turbines, however the stability must be maintained. 67 Higher grade S500 steel costs 20%-25% more than S335 steel (standard structural steel ), but it requires 30% less material because of its improved strength. [1] Materials that are typically used for the rotor blades in wind turbines are composites, as they tend to have a high stiffness, high strength, high fatigue resistance, and low weight. 46 Typical resins used for these composites include polyester and epoxy, while glass and carbon fibers have been used for the reinforcing material. 47 Construction may use manual layup techniques or composite resin injection molding. [2] Since it is the most widely used material for reinforcement in composites around the globe, the expansion of end use applications such as construction, transportation and wind turbines has fueled its popularity. [2] Modern turbines use a couple of tons of copper for generators, cables, and such. 52 Smaller wind turbines have begun incorporating more aluminum based alloys into these components in an effort to make the turbines lighter and more efficient, and may continue to be used increasingly if fatigue and strength properties can be improved. [2] Small wind turbines may be as small as a fifty-watt generator for boat or caravan use. [2] Small wind turbines (under 50kW) with variable- pitching generally use systems operated by centrifugal force, either by flyweights or geometric design, and employ no electric or hydraulic controls. [1] This article covers the design of horizontal axis wind turbines (HAWT) since the majority of commercial turbines use this design. [1]

Wind turbines are available in different power ratings due to their differences in size. [3] The generator in a wind turbine produces alternating current (AC) electricity. [1] They will produce electricity at between two and six cents per kilowatt hour, which is one of the lowest-priced renewable energy sources. 72 And as technology needed for wind turbines continues to improve, the prices will decrease as well. [2] Taking on a completely different role from a fan (which produces wind from electricity), wind turbines creates electricity from wind. [3]

The Global Wind Energy Council (GWEC) predicts that wind energy will supply 15.7% of the world’s total energy needs by the year 2020, and 28.5% by the year 2030. 50 This dramatic increase in global wind energy generation will require installation of a newer and larger fleet of more efficient wind turbines and the consequent decommissioning of aging ones. [1] For large wind farms distances of about 15 rotor diameters should be more economical, taking into account typical wind turbine and land costs. [2] On most horizontal wind turbine farms, a spacing of about 6-10 times the rotor diameter is often upheld. [2] Vertical-axis wind turbines (or VAWTs) have the main rotor shaft arranged vertically. [2] Braking of a small wind turbine can be done by dumping energy from the generator into a resistor bank, converting the kinetic energy of the turbine rotation into heat. [1] Utility-scale wind turbine generators have minimum temperature operating limits which apply in areas that experience temperatures below ?20C (?4F). [1] For every bird killed by a wind turbine in the U.S., nearly 500,000 are killed by each of feral cats and buildings. 78 In comparison, conventional coal fired generators contribute significantly more to bird mortality, by incineration when caught in updrafts of smoke stacks and by poisoning with emissions byproducts (including particulates and heavy metals downwind of flue gases). [2] Permanent magnets for wind turbine generators contain rare earth metals such as Nd, Pr, Tb, and Dy. [2] The survival speed of commercial wind turbines is in the range of 40m/s (144km/h, 89 MPH) to 72m/s (259km/h, 161 MPH). [1] Materials for wind turbine parts other than the rotor blades (including the rotor hub, gearbox, frame, and tower) are largely composed of steel. [2] Wood is being investigated as a material for wind turbine towers, and a 100 metre tall tower supporting a 1.5 MW turbine has been erected in Germany. [1] As of 2003, typical modern wind turbine installations use towers about 210ft (65 m) high. [1] Largest capacity conventional drive The Vestas V164 has a rated capacity of 8MW, 79 later upgraded to 9 MW. 80 The wind turbine has an overall height of 220m (722ft), a diameter of 164m (538ft), is for offshore use, and is the world’s largest-capacity wind turbine since its introduction in 2014. [2] Several modern wind turbines use rotor blades with carbon-fibre girders to reduce weight. [1] There are patents that present designs with additional blades, such as Chan Shin’s Multi-unit rotor blade system integrated wind turbine. 26 Aerodynamic efficiency increases with number of blades but with diminishing return. [1] The world currently longest wind turbine rotor blade, the 88.4 m long blade from LM Wind Power is made of carbon/glass hybrid composites. [2] In July 2016, Siemens upgraded its 7 to 8MW. 81 Largest vertical-axis Le Nordais wind farm in Cap-Chat, Quebec has a vertical axis wind turbine (VAWT) named. ole, which is the world’s largest at 110m. 82 It has a nameplate capacity of 3.8MW. 83 Largest 1-bladed turbine Riva Calzoni M33 was a single-bladed wind turbine with 350kW, designed and built In Bologna in 1993. 84 Largest 2-bladed turbine The biggest 2-bladed turbine is built by Mingyang Wind Power in 2013. [2] There is no competitive market for wind energy, as it does not cost money to get ahold of wind. 72 The main cost of wind turbines are the installation process. [2] Wind turbines convert wind energy to electrical energy for distribution. [2]

The lowest velocity at which the turbine develops its full power is known as rated wind velocity. [1] A fully stalled turbine blade, when stopped, has the flat side of the blade facing directly into the wind. [1] A fully furled turbine blade, when stopped, has the edge of the blade facing into the wind. [1] Standard modern turbines all furl the blades in high winds. [1] Considering wind, it is expected that turbine blades go through ~10^9 loading cycles. [1] Small turbines are pointed by a simple wind vane, while large turbines generally use a wind sensor coupled with a yaw system. [2] “Wind Turbine – Materials and Manufacturing Fact Sheet”. [2] “Wind Turbines: Fundamentals, Technologies, Application, Economics” p142. [1]

It has a total height of 230m, and a hub height of 164m on 100m concrete tower bottom with steel tubes on top (hybrid tower). 88 Vestas V164 was the tallest wind turbine, standing in terild, Denmark, 220 meters tall, constructed in 2014. [2] A 100 m prototype tower with TC bolted 18mm ‘plank’ shells has been erected at the wind turbine test center Hse in Denmark and certified by Det Norske Veritas, with a Siemens nacelle. [1] Currently, the majority of wind turbines are supported by conical tubular steel towers. [1] Another disadvantage of conical steel towers is that constructing towers that meet the requirements of wind turbines taller than 90 meters proves challenging. [1] New type of wind turbine tower Metal Industry, 8 August 2011. [1] Inside view of a wind turbine tower, showing the tendon cables. [2] Typically wind turbines generate electricity through asynchronous machines that are directly connected with the electricity grid. [1] In the autumn of 1941, the first megawatt-class wind turbine was synchronized to a utility grid in Vermont. [2] All wind turbines are designed for a maximum wind speed, called the survival speed, above which they will be damaged. [1] Wind turbines, by their nature, are very tall slender structures, 84 this can cause a number of issues when the structural design of the foundations are considered. [1] Innovation in Wind Turbine Design sec11-1, John Wiley & Sons, 5 July 2011. [1] The efficiency of a wind turbine is maximum at its design wind velocity, and efficiency decreases with the fluctuations in wind. [1] In the case of wind turbines, due to the high wind and environmental loads experienced there is a significant horizontal dynamic load that needs to be appropriately restrained. [1] This loading regime causes large moment loads to be applied to the foundations of a wind turbine. [1] “Dynamic modelling and control of fully rated converter wind turbines”. [1] A small Quietrevolution QR5 Gorlov type vertical axis wind turbine in Bristol, England. [2] A wind turbine is a device that converts the wind’s kinetic energy into electrical energy. [2] For instance, offshore wind developers in the U.S. are required to undertake automated monitoring of bird and bat behaviour to identify potential collisions with offshore wind turbines. [3] “Full-field dynamic strain prediction on a wind turbine using displacements of optical targets measured by stereophotogrammetry”. [2] Due to data transmission problems, structural health monitoring of wind turbines is usually performed using several accelerometers and strain gages attached to the nacelle to monitor the gearbox and equipments. [2] Modern large wind turbines are typically actively controlled to face the wind direction measured by a wind vane situated on the back of the nacelle. [1]

Because the power of the wind increases as the cube of the wind speed, turbines have to be built to survive much higher wind loads (such as gusts of wind) than those from which they can practically generate power. [1] Doubling the altitude of a turbine, then, increases the expected wind speeds by 10% and the expected power by 34%. [1]

Turbines used in wind farms for commercial production of electric power are usually three-bladed. [2] Arrays of large turbines, known as wind farms, are becoming an increasingly important source of intermittent renewable energy and are used by many countries as part of a strategy to reduce their reliance on fossil fuels. [2] Labor and maintenance costs increase only gradually with increasing turbine size, so to minimize costs, wind farm turbines are basically limited by the strength of materials, and siting requirements. [1]

Stalling works by increasing the angle at which the relative wind strikes the blades ( angle of attack ), and it reduces the induced drag ( drag associated with lift ). [1] If the height of a rooftop mounted turbine tower is approximately 50% of the building height it is near the optimum for maximum wind energy and minimum wind turbulence. [2] Turbine systems that have fewer failures, 92 require less maintenance, are lighter and last longer will lead to reducing the cost of wind energy. [1] A study of the material consumption trends and requirements for wind energy in Europe found that bigger turbines have a higher consumption of precious metals but lower material input per kW generated. [2] Wind power intercepted by the turbine is proportional to the square of its blade-length. 9 The maximum blade-length of a turbine is limited by both the strength and stiffness of its material. [1] Particularly at low-to-medium wind speeds, yawing can make a significant reduction in turbine output, with wind direction variations of 30 being quite common and long response times of the turbines to changes in wind direction. [1] At night time, or when the atmosphere becomes stable, wind speed close to the ground usually subsides whereas at turbine hub altitude it does not decrease that much or may even increase. [1] For a given survivable wind speed, the mass of a turbine is approximately proportional to the cube of its blade-length. [1] 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. [2] Offshore wind farms tend to have larger turbines when compared to onshore installations. [3] Thorntonbank Wind Farm, using 5 MW turbines REpower 5M in the North Sea off the coast of Belgium. [2] “Optimal turbine spacing in fully developed wind farm boundary layers”. [2] Turbines can be placed on ridges or bluffs to maximize the access of wind they have, but this also limits the locations where they can be placed. 72 In this way, wind energy is not a particularly reliable source of energy. [2] Since the wind direction varies quickly the turbine will not strictly follow the direction and will have a small yaw angle on average. [1] One advantage of this arrangement is that the turbine does not need to be pointed into the wind to be effective, which is an advantage on a site where the wind direction is highly variable. [2]

Next time when you hear someone complaining about how wind turbines are causing noise and aesthetic pollution, with a better understanding of how do wind turbines work, you can explain convincingly wind power sceptics, who may not have a good understanding of green energy, about how wind turbines function to generate alternative clean power from wind, which is one of the fastest-growing renewable resources in the world. [4] It is hoped that after going through the functions and roles played by the main components of a wind turbine installation described in this post, it should be easier to understand the basics of wind power technology and answer how does a wind turbine work to produce electricity. [4] To explain how do wind turbines work, the description of the important components of the wind turbine installation and the roles played by them to capture the wind’s energy, point the turbine into the wind, convert the mechanical energy at the rotor shaft into electrical energy and to start, stop, and control the turbine, are detailed below. [4] How does a wind turbine work is one of the frequently asked questions about wind energy which is one of the fastest-growing renewable resources in the world. [4] How does a wind turbine work – functions of the major components. [4] To ensure wind turbines that are big in size work in a better manner, a new kind of air-flow technology may soon be introduced. [5]

The Pitch system in a wind turbine is a closed loop drive system that controls the angle of the turbine blades by rotating them so that the blades use the right amount of the available wind energy to get the most power output, at the same time ensuring that the turbine does not exceed its maximum rotational speed. [4] The power from the rotation of the wind turbine rotor is transferred to the generator through the power train, i.e. through the low-speed shaft (the main shaft), the gearbox and the high speed shaft. [4] The energy in the wind turns the turbine blades around the rotor, which spins the power generator and the generator converts the mechanical energy at the shaft of the turbine into electrical energy by using an electromagnetic field. [4] The wind pushes directly against the blades of the turbine, which converts the linear motion of the wind into the rotary motion necessary to spin the generator rotor to produce electricity by using an electromagnetic field. [4]

The taller towers enable wind turbines to capture more energy and generate more electricity because the wind speed increases farther away from the ground and wind blows more steadily at a higher atmosphere. [4] The tower of a wind turbine supports the Nacelle and the Rotor (the hub with three attached blades). [4] The net result is a lifting force perpendicular to the direction of flow of the air over the turbines blades which creates torque in the wind turbine rotor and causes it to spin like a propeller. [4] The turbine blades and the hub together form the rotor of a wind turbine. [4] Wind turbines present a unique problem in that they can be both stationary and moving clutter and operate with blade tip speeds up to 200 knots, in the same range of aircraft speeds. [6] The wind turbine generator converts the rotational mechanical power generated by the rotor blades into electrical energy. [4] Generators using the enabled auto power feature will not power down when the wind turbine kicks back on. [7] It should be noted, however, that onshore and near-shore studies show that the number of birds killed by wind turbines is negligible compared to the number that die as a result of other human activities such as traffic, hunting, power lines and high-rise buildings and especially the environmental impacts of using non-clean power sources. [8] After some server resets you may need to destroy and place wind turbines again to get them to power electrical grids. [7] A French startup called NewWind has developed a new kind of wind turbine: it looks like a tree and needs less wind than a traditional turbine to to create power. [9]

Wind turbines are mounted on a tower to capture energy from the wind. [4] Oct. 9, 2017 – Because wind speeds are higher on average over ocean than over land, wind turbines in the open ocean could in theory intercept more than five times as much energy as wind turbines over land. [8] If the wind speed continues to increase, the wind turbine generator would stop automatically at its cut-out point to prevent any mechanical or electrical damage. [4] The Nacelle is the most important part of the wind turbine that houses the components that transform the wind’s kinetic energy into mechanical energy to turn a generator that produces electricity. [4] Wind power is the conversion of wind energy into more useful forms, such as electricity, using wind turbines. [8] Backed with a $3 million assistance from the Massachusetts Clean Energy Center (MassCEC) Wilbraham-based FloDesign Wind Turbine Corp. will expand its operations in the state. [5] There is no wind strength in Aberration and will not allow Wind Turbine to generate power due to said reason. [7] The Wind turbines, which operate on a simple principle, generate electricity by harnessing the power of the wind. [4] Therefore, power companies continue to operate the natural gas or coal-fired power plants even when the wind turbines are spinning so that they can immediately replace their power when the wind dies down. [10] The rotor of the wind turbine rotates at a relatively slow speed. [4] The wind turbine blades are the core of conversion of kinetic energy of wind to rotary-mechanical energy. [4] The blades of a wind turbine are shaped with one side (rear) much more curved than the other side (front). [4] The effect of the rotor orientation i.e. upwind or downwind, has a dominating impact on the unsteady loads of the wind turbine system. [4] The controller of the wind turbine will always make sure that the rotor is turned into the wind. [4] Iowa State Aerospace Engineers Anupam Sharma and Hui Hu are exploring the possibility of adding a smaller, secondary rotor to wind turbines. [5] To optimize the functionality of a wind turbine, a control system is used. [4] The control system consists of a number of computers which constantly monitor the condition of the wind turbine and collect statistics of operation from the sensors. [4] A wind turbine is a machine for converting the mechanical energy in wind into electrical energy. [11] How does a wind turbine work- wind power generation basics explained Mon. [4] Presently Fluid Dynamics Expert, John Dabiri, is very much on the quest of improving designs of wind turbines. [5] The IFT&E program was established in response to directives from Congress and the White House to investigate and address the concerns of the growing interference of wind turbines on our nation’s air surveillance radars. [6] The primary braking system for most modern wind turbines is the aerodynamic braking system which stops the turbine in a matter of a couple of rotations. [4]

The upwind turbines have the rotor in front of the nacelle facing the wind while downwind turbines have the rotor behind the nacelle and facing away from the wind. [4] GE, the U.S. industrial group, is promoting and showing confidence in offshore wind technology by buying ScanWind, which makes direct-drive turbine components. [5]

May 20, 2016 – A Finnish invention, a vertical axis Savonius wind turbine can be further improved shows a new study. [11]

Wind turbines work on land or offshore locations wherever consistent wind patterns keep the blades spinning. [12] The blades are designed with complex aerodynamic curves to look and work like modern-day wind turbine blades. [13] Drone technology offers a safe and effective alternative to the vital work of inspecting wind turbines. [12] Rusty Beals, who owns the company with partner Dickie Pruett, was sorting out parts for the 42-foot-tall wind turbine, checking things out and making necessary changes before going to the work site. [14]

The blades work by generating lift and drag due to their difference in shapes when the wind blows over them, like an airplane. [4] The two primary aerodynamic forces that work in wind-turbine rotors are lift, which acts perpendicular to the direction of wind flow and drag, which acts parallel to the direction of flow. [4]

Most modern wind power is generated in the form of electricity by converting the rotation of turbine blades into electrical current by means of an electrical generator. [8] Wind power is used in large scale wind farms for national electrical grids as well as in small individual turbines for providing electricity to rural residences or grid-isolated locations. [8]

It also houses a Controller that receives data from an Anemometer, which measures wind speed, a Vane, which measures wind direction, a Pitch control system that controls the angle of the blades, and the Yaw drive, which controls the position of the turbine relative to the wind. [4] Wind direction determines the design of the turbines whether upwind or downwind. [4] That means they have determined through either Apex’s information or their own, that the 75 MW wind farm would produce no more than 10.1MW or 13 percent of the rated capacity of the 25 turbines. [10] Turbines do not operate at wind speeds above around 55 mph because the high winds may damage the turbines. [4]

A generator 30 lengths away, and a turbine on the opposite end will not work. [7] As long as one turbine itself doesn’t end up in the exclusion zone of another, they will work. [15]

In windmills (a much older technology), wind energy is used to turn mechanical machinery to do physical work, such as crushing grain or pumping water. [8]

There is a simple rule of thumb for wind turbines: The bigger the blades — or rotor diameter — the more power it can generate. [16] The first and the commonly used type is the horizontal axis wind turbine, which has a tower and blades that turn to generate electricity. [17] Although wind turbines cost a lot of money to construct, they can be used as a part of alternative energy harnessing strategies, especially in pragmatic areas feasible for the functioning of these machines. [17] HAWT or horizontal axis wind turbines give better energy returns only at areas with high and fairly constant wind speeds, and are very expensive to build and transport. [17]

Energy producers try to locate turbines in areas that meet standards for winds but also in areas where turbines represent a high use of the land. [12] In case you are wondering to use the electricity generated by the turbine to power the coaches – that isn?t possible as there is no guarantee that enough wind will be always present. [18]

Read about different types of wind turbines and windmills, the history of this technology, and how wind energy can be used to power homes and electric cars. [13] Build a realistic wind turbine to harness power out of thin air. [13] Wind turbines are being constructed, and wind farms are being developed to harvest energy all over the globe. [17] Wind turbines are a reliable and growing source of electric power in the U.S. as well as globally. [12] Dickie Pruett (left), engineer Ken Carothers and Rusty Beals unwrap a wind turbine blade at Industrial Projects and Services. [14] Conduct experiments with your wind turbine, including experiments to optimize its performance by adjusting the angle of the blades and the placement of the turbine. [13] The second and lesser known design is the vertical axis wind turbine or VAWT, where the rotor is arranged in a vertical direction, and is not pointed towards the direction of the wind. [17] Assemble a wind turbine complete with electric generator and adjustable rotor blades. [13] Convert the wind turbine into an electric fan by using the electric generator as a motor. [13] Are wind turbines competent tools of harnessing energy? As with all machines and energy conversion tools, there is some loss of energy in the windmills, and it does not convert all the wind energy to electrical energy. [17] A “normal” wind turbine can withstand wind speeds of up to 42.5 meters per second, or about 94 miles per hour. [16] Use the wind turbine to light up an LED and charge a rechargeable battery. [13] Wind turbines require regular maintenance and inspection to ensure proper operation and safety. [12] The company has installed about 20 wind turbines and a large number of household and commercial solar units in central and north Texas. [14] Even as wind turbines grow in popularity as renewable energy solutions, the difficulty of maintaining them can limit the locations and usefulness of this beneficial energy technology. [12]

Their shrouded turbine works by creating a rapid-mixing vortex when wind hits it, and has fins that allow it to turn into the wind for maximum energy. [19] “I?m also hoping that I can hit them up for some old worn out solar panels and wind turbines that kids can tear apart and get a hands-on experience and understanding of how a solar panel works and how a wind turbine works,” he said. [20]

The power produced by wind has taken the energy industry by storm in recent years, but there is still much work to be done to fully leverage this renewable resource. [21] Longer blades are typically better because they work like a lever and need less wind to make the generator spin. [16]

“Sometimes you are limited by the roads and bridges in Japan, so you need blades that can actually access the area for your wind farm,” Hidalgo says, adding that it takes nine trucks to transport the typhoon turbine to its location. [16] A trip throughout the western portion of the United States unveils large-scale wind farms full of large turbines designed and built to trap wind energy for the purpose of producing large amounts of electric power. [21] Today we are focused on utilizing wind energy to meet our planet’s critical energy needs through the use of turbines. [21] A turbine can convert a maximum of about 59% of the wind energy to electrical energy. [17]

Have an in depth understanding of the different components of the wind turbine including the electrical pitch system, computerized control system, and the power conversion unit as well as knowledge and understanding of OEM approved mechanical maintenance methods and practices. [22] Troubleshoot complicated mechanical, hydraulic, and electrical problems on variable pitch, variable speed wind turbines. [22]

Five massive wind turbines floating in the sea near Scotland have started sending energy to the grid. [23] Most of us can agree that more clean energy is a good thing, but a surprising number of folks still don?t want wind turbines built in their backyards. [24] Stutzman says he’s not concerned about blades from the wind turbine breaking off. [20] Missouri Basic 500 Watt 7 Blade Wind TurbineOur Basic Raptor Wind Turbine for home, business, or rem. $289.98 [25] Our vibration sensors, speed sensors and temperature sensors provide a variety of real-time and precise inspection data with their superior performance and reliability, enabling engineers to perform efficient equipment monitoring and maintenance and maximize the use of wind turbines. [26] Plus, a bad day for a wind turbine on the ground is when the rotor smashes the tower. [19] Redesigning the traditional wind turbine — large three-bladed rotors with controllable pitch — is sort of like reinventing the wheel. [19] Offshore wind turbines could soon provide more electricity for Germany — to the tune of 1,610 megawatts (MW). [23] The ongoing quest for cheaper, more efficient wind energy has produced wacky wind turbine ideas. [19] UNITED STATES: A recently released database of American wind turbines provides evidence that lifetimes of 20 years or more can easily be realised, with the oldest machines having been commissioned 37 years ago in 1981. [24] Possess an A.S. degree (electrical or technical) and six months turbine experience, or one year wind turbine experience. [22] The wind turbine will last 15 years, and, at the end of 15 years, we?ll put something else up or retire it. [20] Wind turbines kill up to 750,000 birds every year, according to Donald Trump’s Secretary of the Interior Ryan Zinke. [23] Conventional wind turbines remain expensive and require tons of material. [19] ASHTON – The Bonneville Environmental Foundation and Fall River Electric recently joined forces to install a solar panel and a wind turbine at North Fremont High School. [20] Fremont County Superintendent Byron Stutzman said that the school district and North Fremont High School officials are confident that the money to install the wind turbine and the solar panels will be made possible and soon. [20] Vertical Axis Wind Turbine are simple, compact and easy to maintain. [27]

Wind energy has been in use for quite a long time now, with windmills being used effectively to do mechanical work. [17] Kingspan will continue to market the wind turbine range within their energy portfolio, and will work with SD Wind Energy over the coming months to ensure a smooth transition for all stakeholders. [28] According to Mr. Leon Gouws of Eveready one of the leading wind turbine manufacturers in Africa, blades are very important in noise reduction, high wind speed survival and high performance energy output. [29] BHI Energy is currently recruiting Wind Turbine Blade Repair Technicians for various locations. [30] Published on June 29, 2018 As demand for cleaner energy rises, wind turbine manufacturers continue to develop groundbreaking solutions to produce power more efficiently and reliably than ever before. [31] The world’s largest wind farm, the Horse Hollow Wind Energy Center in Texas, has 421 wind turbines that generate enough electricity to power 230,000 homes per year. [32] Wind turbines will normally start generating electricity at a wind speed of 3 to 5 metres per second (m/s), attain maximum power at 15 m/s and ordinarily cut-out at a wind speed of around 25 m/s. [29]

Other concepts for generation that influence the wind turbine cost are also available, for instance the gearless “direct drive? turbines with variable speed generator designs have a significant presence in the market. [29] The wind turbine cost normally depends on the material used to manufacture the blades. [29] “To keep up with energy demands, offshore wind projects are utilizing larger, higher-capacity wind turbines which are capable of capturing more wind-produced energy at much lower operating costs,” says DSTI Vice President of Business Development John Knoll. [31] Most importantly, Mark L Cironi from Green Energy Technologies from the U.S. advises customers to understand the difference between Utility Scale wind turbines from on-site decentralized wind turbines. [29] SD Green Energy of Tokyo, Japan uwavazybtuvvevsv has purchased the wind turbine product range from Scottish company Kingspan. [28] For nearly a decade, DSTI has provided leading wind turbine equipment manufacturers with blade pitch control solutions for safely transmitting electrical signals and hydraulic fluid from a turbine’s nacelle to the rotating hub. [31] New materials like carbon fiber are being initiated to provide the high strength-to-weight ratio required for the ever larger wind turbine blades being manufactured. [29] Verticalaxis wind machines have blades that go from top to bottom and the most common type (Darrieus wind turbine) looks like a giant two-bladed egg beaters. [32] Job Description: Inspect and repair wind turbine composite components (blades, nose cones, hatches etc.) by using industry… lbs. [33] The Wind Technician at the Bishop Hill II Wind Farm in Galva, IL will be responsible for the operations, maintenance, and warranty repair of wind turbine generators. [30] The Services Lead Technician is responsible for leading troubleshooting crews and providing. repair of wind turbine generators in a safe manner. [30] Various design concepts of the horizontal-axis wind turbine are in use in this modern era. [29] SD Wind Energy will take on existing customers which includes an installed fleet of over 5,000 wind turbines globally and will continue to provide uninterrupted warranty and field support to the entire global fleet. [28] The Plant Technician I is responsible for the on-site operations, maintenance, repairs, and. wind turbines and associated wind plant equipment and systems including substations, met towers. [30] The Materials/Receiving Technician is responsible for initial receipt of General Electric (GE) wind turbine components as they arrive to site, proper direction of components and materials to lay-down. [30] There are two types of wind machines (turbines) used today based on the direction of the rotating shaft (axis): horizontalaxis wind machines and vertical-axis wind machines. [32] Wind River Environmental is the leader in non-hazardous liquid waste services with a recent focus. turbine pumps, de-sanding systems, control panels, and pump. savers. [30] Each module has a pair of small, high capacity turbines mounted to both of its concave wind amplifier module channel surfaces. [32] A yaw mechanism guarantees that the turbine always faces the wind. [29] RES, the company behind the wind parks project in the towns of Hanover and Villenova, has submitted applications to both town boards for an amendment to the project, which asks for turbine heights of 599 feet, taller than any land-based turbines in the country. [34]

DSTI recently partnered with pitch control industry experts and examined both field-proven and innovative technologies to develop the next generation of hydraulic pitch control rotary unions for 6MW-plus wind turbines. [31] “Generally speaking, to install a wind turbine, the average annual wind speed should be at least 3m/s,” she adds. [29] A typical modern wind turbine can be broken down into various major parts that also majorly affect the wind turbine cost. [29] Contractors must also evaluate wind turbine hazards such as unguarded moving parts and exposed electrical components. [35] Greg Smith, a Bloom Township resident who lives in the project area for sPower’s Seneca Wind project, provided information about several wind turbine projects slated for Seneca and surrounding counties and said the cause has gained momentum. [34] The groundbreaking standard – specifically named Safety Requirements for Safe Construction and Demolition of Wind Generation/Turbine Facilities – establishes minimum requirements for protecting workers involved in the construction and demolition of a utility-scale, land-based wind turbine, a device that converts the wind’s kinetic energy into electrical energy. [35] Ensure proper operation and maintenance of wind turbines and associated wind turbine equipment ?Proactively look for improvement… hydraulic and mechanical systems to maintain wind turbine operation at EDPR NA’s wind -energy generation sites. [33] “A customer needs to focus and choose a suitable wind turbine for his particular need. [29] This global growth underscores the need for wind turbine construction and demolition to be conducted in a safe manner. [35]

It appears wind power and solar power are here to stay, even as President Donald Trump’s administration works to. [23] Windmills work because they slow down the speed of the wind. [32] “It includes nearly a dozen appendixes that identify additional considerations for specific scopes of work found in wind projects.” [35]

The wind farm consists of 73 turbines and produces 165.5MW of renewable power in ideal wind conditions. [36] Larger turbines are often grouped together into wind farms that provide power to the electrical grid. [32] The wind farm operator is therefore able to have the complete information and control of the turbines from a remote location. [29] Collections of large turbines, known as wind farms, are a growing source of renewable energy that provide an alternative to fossil fuels. [35] The concave surfaces channel wind toward the turbines, amplifying wind speeds by 50 percent or more. [32]

Among the challenges are the remoteness of the work, turbine height, limited access and turbine manufacturer variables. [35]


The turbine’s rotation can be kept at a safe speed in faster winds while maintaining (nominal) power output. [1] The maximum theoretical power output of a wind machine is thus 0.59 times the kinetic energy of the air passing through the effective disk area of the machine. [1]

Stalling is simple because it can be made to happen passively (it increases automatically when the winds speed up), but it increases the cross-section of the blade face-on to the wind, and thus the ordinary drag. [1] The cycloturbine variety has variable pitch to reduce the torque pulsation and is self-starting. 33 The advantages of variable pitch are: high starting torque; a wide, relatively flat torque curve; a higher coefficient of performance; more efficient operation in turbulent winds; and a lower blade speed ratio which lowers blade bending stresses. [2] The ratio between the speed of the blade tips and the speed of the wind is called tip speed ratio. [1]

A major problem in desert environments is erosion of the leading edges of blades by wind carrying sand, which increases roughness and decreases aerodynamic performance. [1]

As a form of solar energy, wind is caused by these elements: the rotation of the earth, the earth’s irregular surface and the uneven heating of the atmosphere by the sun. [3] In high winds, the blades can also be allowed to bend which reduces their swept area and thus their wind resistance. [2] Typically, the glass/epoxy composites for wind blades contain up to 75 weight% glass. [2]

Here again the 1/7 power law applies or is at least a good approximation of the wind profile. [1] Wind velocities increase at higher altitudes due to surface aerodynamic drag (by land or water surfaces) and the viscosity of the air. [1] Therefore, an increase in wind production would increase the demand for these resources. [2]

Downwind machines have been built, because they don’t need an additional mechanism for keeping them in line with the wind. [2] In 1919, the physicist Albert Betz showed that for a hypothetical ideal wind-energy extraction machine, the fundamental laws of conservation of mass and energy allowed no more than 16/27 (59.3%) of the kinetic energy of the wind to be captured. [1]

Course notes from Scoraig Wind Electric, used in courses at the Centre for Alternative Technology. [1] No matter how much wind is used today, there will still be the same supply in the future. [3]

Such brakes are usually applied only after blade furling and electromagnetic braking have reduced the turbine speed generally 1 or 2 rotor RPM, as the mechanical brakes can create a fire inside the nacelle if used to stop the turbine from full speed. [1] 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. 25 Some turbines use a different type of generator suited to slower rotational speed input. [2] The gearbox converts the turning speed of the blades 15 to 20 rotations per minute for a large, one-megawatt turbine into the faster 1,800 revolutions per minute that the generator needs to generate electricity. 12 Analysts from GlobalData estimate that gearbox market grows from $3.2bn in 2006 to $6.9bn in 2011, and to $8.1bn by 2020. [1]

Component costs that are affected by blade count are primarily for materials and manufacturing of the turbine rotor and drive train. [1] Using carbon fibres in 60 metre turbine blades is estimated to reduce total blade mass by 38% and decrease cost by 14% compared to 100% fibreglass. [1] Turbines with one or two blades can use a pivoting teetered hub to also nearly eliminate the cyclic loads into the drive shaft and system during yawing. [1] These cyclic loads when combined together at the drive train shaft are symmetrically balanced for three blades, yielding smoother operation during turbine yaw. [1] Load reduction is currently focused on full-span blade pitch control, since individual pitch motors are the actuators currently available on commercial turbines. [1] Since blade mass scales as the cube of the turbine radius, loading due to gravity constrains systems with larger blades. 41 Gravitational loads include axial and tensile/ compressive loads (top/bottom of rotation) as well as bending (lateral positions). [1] This method is useful if the kinetic load on the generator is suddenly reduced or is too small to keep the turbine speed within its allowed limit. [1] The most common method in large modern turbines is to instead use a doubly fed induction generator directly connected to the electricity grid. [1] In some cases, especially when turbines are sited offshore, the DC energy will be transmitted from the turbine to a central (onshore) inverter for connection to the grid. [1] The very nature of the way in which energy is extracted from the air also causes air to be deflected by the turbine. [1] The air flow at the blades is not the same as the airflow far away from the turbine. [1] Retrofitting current turbines with larger blades mitigates the need and risks associated with a system-level redesign. [2] The largest turbines have blades the length of a football field. [3] The smallest turbines are used for applications such as battery charging for auxiliary power for boats or caravans or to power traffic warning signs. [2] 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. [2] A mechanical drum brake or disk brake is used to stop turbine in emergency situation such as extreme gust events or over speed. [1] Prestressed concrete has been increasingly used for the material of the tower, but still requires much reinforcing steel to meet the strength requirement of the turbine. [2] Swedish analyses show that it is important to have the bottom wing tip at least 30 m above the tree tops, but a taller tower requires a larger tower diameter. 59 A 3 MW turbine may increase output from 5,000 MWh to 7,700 MWh per year by going from 80 to 125 meter tower height. 60 A tower profile made of connected shells rather than cylinders can have a larger diameter and still be transportable. [1] Most horizontal axis turbines have their rotors upwind of its supporting tower. [2] Marine life is affected by water intakes of steam turbine cooling towers (heat exchangers) for nuclear and fossil fuel generators, by coal dust deposits in marine ecosystems (e.g. damaging Australia’s Great Barrier Reef) and by water acidification from combustion monoxides. [2] As turbine blades pass 60 metres, infusion techniques become more prevalent; the traditional resin transfer moulding injection time is too long as compared to the resin set-up time, limiting laminate thickness. [1] A subtype of Darrieus turbine with straight, as opposed to curved, blades. [2] For instance, the spar cap, a structural element of a turbine blade, commonly experiences high tensile loading, making it an ideal candidate to utilize the enhanced tensile properties of carbon fiber in comparison to glass fiber. 47 Higher stiffness and lower density translates to thinner, lighter blades offering equivalent performance. [2] The load on the turbine increases if the brake is applied at rated RPM. Mechanical brakes are driven by hydraulic systems and are connected to main control box. [1] It can make anemometer readings inaccurate and which, in certain turbine control designs, can cause high structure loads and damage. [1] This Betz’ law limit can be approached by modern turbine designs which may reach 70 to 80% of this theoretical limit. [1] This brake is a secondary means to hold the turbine at rest for maintenance, with a rotor lock system as primary means. [1] Largest capacity direct drive The Enercon E-126 with 7.58MW and 127m rotor diameter is the largest direct drive turbine. [2] These towers represent 30% – 65% of the turbine weight and therefore account for a large percentage of the turbine transportation costs. [1] “Eggbeater” turbines, or Darrieus turbines, were named after the French inventor, Georges Darrieus. 31 They have good efficiency, but produce large torque ripple and cyclical stress on the tower, which contributes to poor reliability. [2] Usual tubular steel towers of multi megawatt turbines have a height of 70 m to 120 m and in extremes up to 160 m. [2] Direct-drive turbines require 600kg of permanent magnet material per megawatt, which translates to several hundred kilograms of rare-earth content per megawatt, as neodymium content is estimated to be 31% of magnet weight. [1] Systems that use magnetic direct drive turbines require higher amounts of rare metals. [2] Other turbines use an electric servomotor for every rotor blade. [1] The turbine has parted rotor blades with 2 sections for transport. [2] These include E-glass/carbon, E-glass/aramid and they present an exciting alternative to pure glass or carbon reinforcements. that the full replacement would lead to 80% weight savings, and cost increase by 150%, while a partial (30%) replacement would lead to only 90% cost increase and 50% weight reduction for 8 m turbine. [2] Some turbine manufacturers offer low-temperature packages at a few percent extra cost, which include internal heaters, different lubricants, and different alloys for structural elements. [1] The reliability of direct drive turbines offshore is still not known, since the sample size is so small. [1] They did not address requirements for small turbines or offshore turbines since those were not widely deployed in 2008, when the study was created. [2] It is a SCD6.5MW offshore downwind turbine, designed by aerodyn Energiesysteme. 85 86 87 Largest swept area The turbine with the largest swept area is the Samsung S7.0-171, with a diameter of 171m, giving a total sweep of 22966m 2. [2] Conservation of mass requires that the amount of air entering and exiting a turbine must be equal. [2]

A daytime atmosphere is either neutral (no net radiation; usually with strong winds and heavy clouding) or unstable (rising air because of ground heating–by the sun). [1] Notably, the relative available output from wind and solar sources is often inversely proportional (balancing) citation needed. [2] Manufactures such as Nordex SE and GE Wind use an infusion process. [1] Failure in ultimate loading of wind-turbine rotor blades exposed to wind and gravity loading is a failure mode that needs to be considered when the rotor blades are designed. [1] Land, whbich might not be considered a material, is an important resource in deploying wind technologies. [2] ” 11 years of wind data shows surprising production decrease ” (in Danish) Ingenien, 1 November 2013. [2] According to National Geographic, cumulative wind capacity around the world increased from 17,000 megawatts to more than 430,000 megawatts between 2000 and 2015. [3]

Below rated wind speed, the generator torque control is active while the blade pitch is typically held at the constant angle that captures the most power, fairly flat to the wind. [1] When the wind speed is below rated, generator torque is used to control the rotor speed in order to capture as much power as possible. [1]

In addition to aerodynamic design of the blades, design of a complete wind power system must also address design of the hub, controls, generator, supporting structure and foundation. [1] In simple designs, the blades are directly bolted to the hub and are unable to pitch, which leads to aerodynamic stall above certain windspeeds. In other more sophisticated designs, they are bolted to the pitch bearing, which adjusts their angle of attack with the help of a pitch system according to the wind speed to control their rotational speed. 25 The pitch bearing is itself bolted to the hub. [1] Loads can be reduced by making a structural system softer or more flexible. 4 This could be accomplished with downwind rotors or with curved blades that twist naturally to reduce angle of attack at higher wind speeds. These systems will be nonlinear and will couple the structure to the flow field – thus, design tools must evolve to model these nonlinearities. [1]

Modern turbines usually have a small onboard crane for hoisting maintenance tools and minor components. [2] Local activists in Germany, nascent turbine manufacturers in Spain, and large investors in the United States in the early 1990s then lobbied for policies that stimulated the industry in those countries. [2]

Above rated wind speed, the generator torque is typically held constant while the blade pitch is active. [1] A natural strategy, then, is to allow the blade to stall when the wind speed increases. [1] To protect components from undue wear, extracted power is held constant above the rated operating speed as theoretical power increases at the cube of wind speed, further reducing theoretical efficiency. [2] Typically, the variation follows the wind profile power law, which predicts that wind speed rises proportionally to the seventh root of altitude. [1]

The St. Leon Wind Farm in Manitoba, Canada, has a total rating of 99MW and is estimated to need up to 3MW (around 3% of capacity) of station service power a few days a year for temperatures down to ?30C (?22F). [1] Wind farms also do not cause pollution as they emit no greenhouse gases or air pollutants, unlike conventional power plants. [3]

The blade size of 49 meters 44 is in comparison to a substation behind them at Wolfe Island Wind Farm. [1]

As wind speed increases, rotor speed should increase proportionally. [1] Sensors detect the wind speed and direction, and motors turn the nacelle into the wind to maximize output. [1] Wind loads are cyclical because of natural variability in wind speed and wind shear (higher speeds at top of rotation). [1]

A report by the United States Geological Survey estimated the projected materials requirement in order to fulfill the U.S. commitment to supplying 20% of its electricity from wind power by 2030. [2] By the 1930s, wind generators for electricity were common on farms, mostly in the United States where distribution systems had not yet been installed. [2]

Wind energy in the 21st century: economics, policy, technology and the changing electricity industry. [2] A quantitative measure of wind energy available at any location is called the Wind Power Density (WPD). [2] Wind power was probably used in Persia (present-day Iran) about 500-900 AD. 2 The windwheel of Hero of Alexandria marks one of the first recorded instances of wind powering a machine in history. 3 4 However, the first known practical wind power plants were built in Sistan, an Eastern province of Iran, from the 7th century. [2] Wind Power: Renewable Energy for Home, Farm, and Business (second ed.). [1] Calculation of wind power density includes the effect of wind velocity and air density. [2]

“Critical and precious materials consumption and requirement in wind energy system in the EU 27”. [2] Siegfried Heier, Grid integration of wind energy conversion systems Wiley 2006, ISBN 978-0-470-86899-7. [1]

The wind speed that causes bending of the rotor blades exhibits a natural variability, and so does the stress response in the rotor blades. [1]

It can work as a dynamic capacitor / inductor bank so as to help with the power systems’ stability. [1] Furling works by decreasing the angle of attack, which reduces the induced drag from the lift of the rotor, as well as the cross-section. [1]

The energy in the wind turns two or three propeller-like blades around a rotor (as shown in the picture). [4] When the wind blows on the angled blades of the rotor, it causes the rotor to spin thereby converting the kinetic energy of the wind into mechanical energy. [4]

When I heard of this project, I found it curious because I did not realize that sufficient wind to produce energy is available in central Virginia. [10] This is not too surprising because industrial wind facilities, at best, only produce 30 percent of their rated energy capacity. [10] It’s an expert estimation that the total energy stored in wind is 100 times higher than actually needed by humans on this earth. [5] At the American Wind Society conference, I learned that the best winds for producing energy in the U.S. are from North Dakota to West Texas and off the eastern U.S. coast, not in the Appalachians. [10]

A local group wrote Apex and requested their wind data so the expected power output for this project could be calculated. [10] Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases. [4]

Even though the technology requires a higher initial investment than fossil-fuelled generators, costs of wind generating systems are much more competitive with other generating technologies on a “life-cycle” cost basis because there is no fuel to purchase and operating expenses are minimal. [4] When the wind changes direction, the nacelle and the rotor follows. [4] The rotor should always be facing the wind in order to catch the wind properly. [4]

This maintains the turbine’s safety in the event of high winds, loss of electrical load, or other harmful events. [4] A wind turbine’s only real drawback is its need for a large open area clear of trees, mountains, buildings, roofs and other tall constructions. [15] Throughout the year in this area, winds are typically light and intermittent. [10]

Each turbine is rated to produce 3 megawatts (MW) of power when spinning at optimum speed. [10] The Gear Box increases the rotational speed of the generator from about 15 to 20 rotations per minute (rpm) for a large, one-megawatt turbine to about 1,800 revolutions per minute that most generators need to generate electricity. [4] Since the rotor shaft is connected to a generator through a gearbox, when the rotor spins, so does the generator and the generator converts the mechanical energy at the shaft of the turbine into electrical energy by using an electromagnetic field. [4] The main body of the turbine sits on top of the tower and behind the blades. [4] Most turbines have either two or three propeller like blades. [4] Multiple turbines in a single power grid can function independently of each other. [7] Turbines will “snap” to existing power grids with cross, angled, or straight cables. [7] Careful though, turbines may give false snap signals while around pillars, walls, gates, and the new giant hatch doors for the roof, never actually snapping to the power lines themselves. [7] Solar generators or farming plots (that are not set to grow trees) can be placed in the exclusion zone without blocking the turbine. [15] The turbine must be within 29 cable lengths of the generator. [7] The aerodynamic braking system offers a very gentle way of breaking the turbine without any major stress, tear and wear on the tower and the machinery. [4] The orientation of turbines doesn’t matter, they will spin equally well in any direction. [15] The low-speed shaft, which is the main shaft of the turbine, has important functions. [4]

The generator (or alternator) will not produce output power until its rotational speed is above its cut-in wind speed where the force of the wind on the rotor blades is enough to overcome friction and the rotor blades accelerate enough for the generator to start generating electricity. [4] Above this cut-in speed, the power output from the generator would rise as a cube of wind speed (i.e. if wind speed doubles, the power output increases eight times) until it reaches its maximum rated power output. [4]

Wind energy is not only cost effective but also doesn’t pollute the air like power plants that rely on combustion of fossil fuels, which emit particulate matter, nitrogen oxides, and sulphur dioxide, causing human health problems. [4] Wind energy too has huge potential to generate power for us. [5]

A fresh-water wind farm is taking shape at Lake Erie and when completed will provide 20 megawatts and get on to about one gigawatt power by 2020. [5] Apex Clean Energy plans to build an industrial wind facility, the Rocky Forge Wind Farm, on North Mountain in Botetourt County. [10] The controller continually optimizes the energy production based upon continuous measurement of mainly wind direction and wind speed. [4] Wind power has recently received a nice boost as one of the hottest forms of energy on the market. [5] At the end of 2006, worldwide capacity of wind-powered generators was 73.9 gigawatts; although it currently produces just over 1% of world-wide electricity use, it accounts for approximately 20% of electricity use in Denmark, 9% in Spain, and 7% in Germany.Globally, wind power generation more than quadrupled between 2000 and 2006. [8] The average output of one megawatt of wind power is equivalent to the average electricity consumption of about 250 American households. [8]

Wind energy is plentiful, renewable, widely distributed, clean, and reduces toxic atmospheric and greenhouse gas emissions if used to replace fossil-fuel-derived electricity. [8] Wind energy currently meets a mere 1.5% of global electricity generation. [5]

Most of this wind energy can be found at high altitudes where continuous wind speeds of over 160 km/h (100 mph) occur. [8] Large-scale onshore and near-shore wind energy facilities (wind farms) can be controversial due to aesthetic reasons and impact on the local environment. [8] No matter how much is used today, there will still be the same supply of wind energy in the future. [4] The effort to develop accurate wind turbine/radar interference models will ultimately improve the understanding of the impact, and allow viable paths to increase the deployment wind energy across the country. [6] Nov. 21, 2016 – Wind energy is a key part of the global energy future, expanding rapidly throughout the world in onshore and offshore settings. [8]

Wind power was the most rapidly-growing means of alternative electricity generation at the turn of the century and world wind generation capacity more than quadrupled between 1999 and 2005. [8] If the mechanical energy is then converted to electricity, the machine is called a wind generator. [11] Wind power is produced by using wind generators to harness the kinetic energy of wind. [5] The intermittency of wind seldom creates problems when using wind power at low to moderate penetration levels. [8]

When it comes to alternative clean power from renewable resources, wind power is expected to occupy the second-largest share of the market after solar in the future. [4] As of 2011, The Empire State Building, one of the world’s largest buildings has achieved the distinction of becoming the largest buyer of green renewable wind power. [5]

It starts up the machine at wind speeds of about 8 to 16 miles per hour (mph) and shuts off the machine at about 55 mph. [4]

It works day and night, compared to a solar generator which only works during the day. [15] Current work supports R&D activities focused on evaluating the potential for an offshore test. [6]

Unlike other methods of harnessing energy, wind does not harm the environment and is recognized as one of the cleanest and safest methods of generating renewable electricity. [21] Pruett became interested in wind and solar energy and advocated adding it to their business. [14] Discover how the sun makes the wind, providing us with an endless source of energy. [13]

In their wind business, they purchase the units through vendors and install everything from a $5,600 1 kilowatt system to a $3 million 1.5 megawatt system with 200-foot blade spans. [14] The organization reports that ancient mariners sailed to distant lands by making use of winds, while farmers used it to pump water used for grinding grains. [21] Wind is defined as the movement of air from high pressure areas to low pressure areas and is actually caused by uneven heating of the earth’s surface by the sun. [21] Last year the region endured 11 of these tropical cyclones, whose winds can toss vehicles into the air, uproot trees and tear roofs from houses. [16]

With the wind and solar sectors growing, the company plans to focus its operations on these areas. [14] BRAZIL: Oil and gas giants Petrobras and Total have extended their partnership with a new memorandum of understanding to investigate wind and solar opportunities in Brazil. [37]

Wind is one of the most promising sources of clean, renewable energy available today. [13]

Despite its clipped wings, the 4.2-117 turbine still packs top-tier power, generating 4.2 MW. You might wonder how smaller turbine blades punch above their weight in terms of power output. [16] SOUTH AFRICA: Siemens Gamesa Renewable Energy (SGRE) has been awarded the turbine supply contract for two projects in South Africa being developed by Mainstream Renewable Power. [37] That’s certainly part of it — GE’s 4.2-117 typhoon-resistant turbine has a relatively modest rotor diameter of 117 meters, which Hidalgo says is critical to reducing the mechanical load on the tower. [16] For instance, the tower that holds the turbine and rotor in the air is made from steel that is thicker than usual. [16]

Cost efficiency can greatly depend on the type of turbine, its location, and design. [17] “These turbines are not a normal class of turbine,” says Ismael Hidalgo, an onshore engineering manager at ? GE Renewable Energy in Barcelona, who is leading the team designing these machines. [16] GE will start assembling a prototype of its typhoon-proof turbine at the National Renewable Energy Laboratory in the Netherlands in June. [16]

As its name suggests, the turbine can generate 1.7 MW. The 4.8 MW version is a whopping 158 meters — just a bit shorter than the Washington Monument. [16]

Wind energy has been used for centuries to pump water and crush grain in windmills, and is increasingly being used to generate electricity to power our modern world. [13] Hidalgo explains that wind power is a factor of the swept area of the blades and wind speed. [16] VAWTs are cheaper to construct, and do not need unidirectional or constant wind speed, but may not give good energy returns on a large-scale basis. [17] With the growing need for alternative sources of energy, man is reusing an old method of tapping wind energy to produce electricity. [17] An association fact sheet shows 3.5 percent of the state’s electricity comes from wind power, and Texas wind farms supply enough power to run 2.5 million homes. [14] An extensive study on the feasibility of the project has to be carried out at the building site, to measure the wind power and its variation in speed. [17] They’re also a threat to the adoption of wind power in island nations like Japan, where wind power represents a small — 3.4 gigawatts — but growing generating capacity. [16] Last week, Industrial Projects and Services, a small company on Highway 6 near Speegleville, was preparing to install a wind energy unit at a China Spring home on Monday. [14] Other areas of Central Texas, especially around Temple and Killeen, have been keen on wind energy. [14] Despite being in a state that’s moving ahead in wind energy development, Waco and the surrounding areas have been slow to catch on, Beals said. [14]

Among one of the best alternatives to using non-renewable resources for our country’s energy consumption is wind energy. [21]

These machines are usually designed to run at a specific wind speed, and any variation in wind velocity can lower their efficiency. [17] With effective drone training, wind farm operators can improve efficiency and lower costs. [12] Installing a wind generator at home can cost you up to $4,000 to $9,000. [17] Making a simple homemade wind generator will cost you much lesser, and if you can afford it, you can then try to scale it up to a bigger size. [17]

The installation requires a bigger crane — but the extra cost can work as insurance for future storms. [16] Though work is being done to improve designs to reduce and limit this loss, it still does persist. [17] Drones work well as camera platforms that operators can control with precision from local or remote locations. [12] The renewable energy work is just part of what the company does, Beals said. [14]

VAWTs have been proven to generate more power per unit land area than HAWTs; this is because micrositing of VAWTs can be done in a way such that there is a better use of the wind rich land. [27] Fourth-fifths of the United States’ electricity demand could be met with wind and solar power, according to four. [23]

Consumers Energy, the principal subsidiary of CMS Energy, has entered into an agreement to own, construct and operate the Gratiot Farms Wind Project, which is currently being developed by Tradewind Energy. [24] Michigan-based CMS Energy is adding two planned wind projects totaling 250 MW to its portfolio. [24]

Denmark set a new renewable energy record in 2017 by obtaining nearly half of its power from wind. [23] The Rock Falls Wind Project, owned and operated by EDF Renewable Energy, is scheduled to begin operation in December. [38] Several years ago Yuji Oyha, a professor at Kyushu University, captured imaginations with his novel design for what he called a “Wind Lens.” [19] While solar dominates in sunny California, in the Great Plains — which are blessed with some of the best wind resources in the world — the lion’s share of renewable generation comes from wi. [24] In the first two months of 2018, the United States installed 1,568 megawatts of wind and 565 MW of solar — which. [23]

The tricky part is that a device with a shroud needs to be able to survive hurricane-force winds. [19]

Their power curve is similar to conventional horizontal axis turbines. [19] Thin glowing green lights connect the rotating blades on several turbines. [19] The falling air rushing through the bottom, where there are turbines that convert the motion into electricity. [19] Accelerometers are manufactured to monitor gearboxes, tower sway, and seismic motion within the turbine. [26] “We proposed looking back at vertical axis turbines for offshore,” he added. [19] Slowly, Vertical Axis turbines are capturing the imagination of many innovators in the field. [27] Job will require standing outside the nacelle and nosecone at the top of the turbine. [22]

AT&T, the Dallas-based telecommunications company, is buying 820 megawatts of electricity generated by wind power from NextEra Energy Resources, a Florida-based producer of electricity. [24] Google just signed new contracts to offset 100% of its energy use with solar and wind power. [23] Addressing NIMBY attitudes that persist around green energy, studio founder Daan Roosegaard also wanted to give wind power the allure it deserves, a press release explains. [19]

Presently setting up a wind farm to harvest energy from wind requires huge capital investment and involves a rat race for wind rich land. [27] The energy from the two wind farms will allow the company to reduce its greenhouse emissions by up to 550,000 metric tons annually. [38] What if the world’s energy problems could be solved with one deep-sea wind farm? A new study, conducted by the. [23]

For the first time, wind energy provided more power than nuclear energy to the United Kingdom grid. [23] Kimberly-Clark will purchase 78 percent of the electricity generated by the Rock Falls Wind project in Kay and Grant counties in northern Oklahoma and 42 percent of the electricity generated by the Santa Rita Wind Energy Center being built in west Texas. [38] Kimberly-Clark Corp. has purchased nearly 1 million megawatt hours of electricity from two new wind power projects in Oklahoma and Texas. [38] Wind power has less life-cycle environmental impact than any other source of utility-scale electricity generation. [24]

Offshore wind power has pulled ahead of nuclear power in the United Kingdom. [23] TE’s solutions for renewable energy help wind industry innovators to develop efficient onshore and offshore wind farms. [26] The world’s first unsubsidized offshore wind farms are currently under construction in the Netherlands. [23] The 30 megawatt Hywind Scotland floating wind farm started operating last fall, and Statoil recently said the farm. [23]

Stutzman also anticipates using some of Fall River’s old energy saving equipment for students to work with. [20] Stutzman says that the energy saving devices are made to work during Fremont County’s hottest summers and its coldest winters. [20]

Documents all work performed, parts used and time spent using computer based service reporting procedures. [22] The concept works like this: Water is pumped to the top of the 2,000-foot-tall cylindrical tower and sprayed into a mist. [19] Able to work with electrical wires and differentiate between color coded wires. [22]

He’s spent more than 40 years working in the wind energy field and helped start the National Wind Technology Center. [19] Ingeteam, a Spanish company that manufactures equipment to generate wind energy, in. [39] Harvesting wind energy is a non-polluting way to generate electricity. [27]

Additionally it accepts wind from any direction at a lower wind speed. [27]

County Clerk Nikki Smith said the county received correspondence from Scipio Township Trustees asking commissioners to rescind the Alternative Energy Zone and letting the county know the township plans to testify to the Ohio Power Siting Board against the Republic Wind and Seneca Wind projects. [34] The Alternative Energy Zone is a program that makes wind projects more economically. [34] Since ancient times, people have harnessed the winds energy. [32] “Wind energy has unique challenges that were simply not adequately addressed in existing standards,” said Christopher Daniels, chair of the A10.21 subcommittee. [35]

Like old fashioned windmills, today’s wind machines use blades to collect the wind’s kinetic energy. [32] Horizontal-axis wind machines have blades like airplane propellers. [32] A typical horizontal wind machine stands as tall as a 20-story building and has three blades that span 200 feet across. [32] The largest wind machines in the world have blades longer than a football field! Wind machines stand tall and wide to capture more wind. [32] The Wind Amplified Rotor Platform (WARP) is a different kind of wind system that is designed to be more efficient and use less land than wind machines in use today. [32]

Unlike power plants, many wind plants are not owned by public utility companies. [32] The wind flows over the airfoil shaped blades causing lift, like the effect on airplane wings, causing them to turn. [32] It also enables the blades to be adorned in high wind conditions to prevent damage. [29]

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2. (90) Wind turbine – Wikipedia

3. (53) How does a wind turbine work- wind power generation basics explained

4. (16) Wind Turbines Cost

5. (15) Wind Turbine Energy from Moving Air

6. (14) Riders On The Storm: GE Is Building A Wind Turbine That Can Weather Violent Typhoons, Hurricanes – GE Reports

7. (14) Laser Windmills Light Up Night Sky – Seeker

8. (14) Wind power

9. (13) Wind Power | Inhabitat – Green Design, Innovation, Architecture, Green Building

10. (13) 7 major specs that influence a modern wind turbine cost

11. (12) Global Wind Day: How do wind turbines work? | DHI Reservoir

12. (12) Wind Power – Alternative Energy

13. (11) Waco company riding wind energy trend | Business |

14. (10) 8 to 10 : Wind Power V3

15. (9) Neas: Does wind energy payoff justify the cost? | Opinion |

16. (8) Drone Technology Assisting in Wind Turbine Inspections

17. (8) Wind Turbine (Scorched Earth) – Official ARK: Survival Evolved Wiki

18. (7) Solar panel wind turbine fundraiser for North Fremont High school | Education |

19. (7) Harnessing Wind Energy | Realestate |

20. (7) Isabella Wind Watch Watch – Posts | Facebook

21. (7) ASSP Publishes First U.S. Standard for Construction and Demolition of Wind Turbines

22. (6) Wind Turbine Tech II

23. (6) General – Vaata SMART Vertical axis wind turbine

24. (6) $35k-$52k International Wind Turbine Technician Jobs (NOW HIRING)

25. (5) Wind turbine – RimWorld Wiki

26. (4) DSTI Boosts Offshore Wind Energy for World’s Largest Turbines – News – DSTI

27. (4) Wind Energy and Wind Power News [Wind Watch]

28. (4) Kimberly-Clark to use wind energy from Oklahoma, Texas wind farms | Work & Money |

29. (4) WTRIM Sandia Energy

30. (3) Wind turbine

31. (3) Wind Turbine Sensors | TE Connectivity

32. (3) Japanese firm buys Scottish wind turbine business – Electric Light & Power

33. (2) Wind Turbine Technician Jobs in Abilene, TX | Glassdoor

34. (2) Latest wind power news & analysis | Windpower Monthly

35. (1) Will it be economical and productive to install a vertical wind turbine on trains? Since the mass of the trains is way higher, will the air resistance really matter? – Quora

36. (1) Missouri Wind and Solar – Alternative Energy Wind Turbines & Solar Panels

37. (1) Gullen Range Wind Farm

38. (1) wind turbine The Daily Reporter WI Construction News & Bids

39. (1) The Newest Wind Turbine Looks Like a Tree – NBC News