In electricity generation, a generator is a device that converts motive power into electrical power for use in an external circuit. Sources of mechanical energy include steam turbines, gas turbines, water turbines, internal combustion engines, wind turbines and even hand cranks. The first electromagnetic generator, the Faraday disk, was invented in 1831 by British scientist Michael Faraday. Generators provide nearly all of the power for electric power grids.
The utility frequency, (power) line frequency or mains frequency is the nominal frequency of the oscillations of alternating current (AC) in a wide area synchronous grid transmitted from a power station to the end-user. In large parts of the world this is 50 Hz, although in the Americas and parts of Asia it is typically 60 Hz. Current usage by country or region is given in the list of mains electricity by country.
Enercon GmbH is a wind turbine manufacturer based in Aurich, Lower Saxony, Germany. It has been the market leader in Germany since the mid-1990s. Enercon has production facilities in Germany, Brazil, India, Canada, Turkey and Portugal. In June 2010, Enercon announced that they would be setting up Irish headquarters in Tralee.
A variable-frequency transformer (VFT) is used to transmit electricity between two alternating current frequency domains. The VFT is a relatively recent development. Most asynchronous grid inter-ties use high-voltage direct current converters, while synchronous grid inter-ties are connected by lines and "ordinary" transformers, but without the ability to control power flow between the systems.
Doubly-fed electric machines also slip-ring generators are electric motors or electric generators, where both the field magnet windings and armature windings are separately connected to equipment outside the machine.
Wind turbine design is the process of defining the form and configuration of a wind turbine to extract energy from the wind. An installation consists of the 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.
An induction generator or asynchronous generator is a type of alternating current (AC) electrical generator that uses the principles of induction motors to produce electric power. Induction generators operate by mechanically turning their rotors faster than synchronous speed. A regular AC induction motor usually can be used as a generator, without any internal modifications. Because they can recover energy with relatively simple controls, induction generators are useful in applications such as mini hydro power plants, wind turbines, or in reducing high-pressure gas streams to lower pressure.
By year end 2015 Spain was the world's fifth biggest producer of wind power with 23,031 MW installed capacity, providing 48,118 GWh of power and 19% of the country's total electricity production in that year. In 2014, a record breaking year for renewable electricity production, wind power accounted for 20.2% of total electricity generation in Spain making it the second most important electricity source after nuclear power (22%) and ahead of coal power (16.5%). In earlier periods wind energy covered 16% of the demand in 2010, 13.8% in 2009 and 11.5% in 2008.
The Ballywater Wind Farm is located between the villages of Kilmuckridge and Ballygarrett, and is located directly beside Ballinoulart in County Wexford, Ireland. It commenced operation in 2005 and has a capacity of 42 MW and consists of 21 gearless E-70 E4 2 MW Enercon wind turbines. It is clearly visible from the R742 regional road. Some of the wind turbines are within a couple of hundred metres of it.
The Littlebrook Power Station were a series of four oil and coal-fired power stations situated on the south bank of the River Thames, next to the Queen Elizabeth 2 Bridge and the Dartford Tunnel in Dartford, Kent. The final power station, Littlebrook D, ceased operating in March 2015, and has now been demolished.
An electrical grid is an interconnected network for electricity delivery from producers to consumers. Electrical grids vary in size and can cover whole countries or continents. It consists of:
A wind turbine is a device that converts the wind's kinetic energy into electrical energy. Hundreds of thousands of large turbines, in installations known as wind farms, now generate over 650 gigawatts of power, with 60 GW added each year. They are an increasingly important source of intermittent renewable energy, and are used in many countries to lower energy costs and reduce reliance on fossil fuels. One study claimed that, as of 2009, wind had the "lowest relative greenhouse gas emissions, the least water consumption demands and... the most favourable social impacts" compared to photovoltaic, hydro, geothermal, coal and gas.
The Enercon E-126 is an onshore wind turbine model manufactured by the German company Enercon. With a hub height of 135 m (443 ft), rotor diameter of 126 m (413 ft) and a total height of 198 m (650 ft), the turbine can generate up to 7.58 megawatts of power, making it the largest wind turbine in the world for several years, until it was overtaken in 2014 by the Danish company Vestas with their V164-8.0 turbine. Their model number is a reference to their rotor diameter.
Starting in 1975, NASA managed a program for the United States Department of Energy and the United States Department of Interior to develop utility-scale wind turbines for electric power, in response to the increase in oil prices. A number of the world's largest wind turbines were developed and tested under this pioneering program. The program was an attempt to leap well beyond the then-current state of the art of wind turbine generators, and developed a number of technologies later adopted by the wind turbine industry. The development of the commercial industry however was delayed by a significant decrease in competing energy prices during the 1980s.
The great majority of wind turbines around the world belong to individuals or corporations who use them to generate electric power or to perform mechanical work. As such, wind turbines are primarily designed to be working devices. However, the large size and height above surroundings of modern industrial wind turbines, combined with their moving rotors, often makes them among the most conspicuous objects in their areas. A few localities have exploited the attention-getting nature of wind turbines by placing them on public display, either with visitor centers on 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.
The following outline is provided as an overview of and topical guide to wind energy:
A variable speed wind turbine is one which is specifically designed to operate over a wide range of rotor speeds. It is in direct contrast to fixed speed wind turbine where the rotor speed is approximately constant. The reason to vary the rotor speed is to capture the maximum aerodynamic power in the wind, as the wind speed varies. The aerodynamic efficiency, or coefficient of power, for a fixed blade pitch angle is obtained by operating the wind turbine at the optimal tip-speed ratio as shown in the following graph.
Synchronverters or virtual synchronous generators are inverters which mimic synchronous generators (SG) to provide "synthetic inertia" for ancillary services in electric power systems. Inertia is a property of standard synchronous generators associated with the rotating physical mass of the system spinning at a frequency proportional to the electricity being generated. Inertia has implications towards grid stability as work is required to alter the kinetic energy of the spinning physical mass and therefore opposes changes in grid frequency. Inverter-based generation inherently lacks this property as the waveform is being created artificially via power electronics.
Growian or GROWIAN was a publicly funded wind turbine built in the Kaiser-Wilhelm-Koog near Marne for purposes of technology testing in the 1980s. It was a two-bladed "lee runner" with a hub height of about 100 metres (330 ft).
S. Morgan Smith was an American manufacturer of turbines, founded by Stephen Morgan Smith in York, Pennsylvania. It was founded in 1877 shortly after Smith received a patent for an improved turbine. It became the country's largest manufacturer of hydroelectric turbines. The company's ability to manufacture large equipment was utilized during World War I to manufacture machines used to make large artillery guns and in World War II to make various large components. The company was purchased by Allis Chalmers and later spun-off to Voith Hydro.
