The Azimuth Project
Wind farm (changes)

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Contents

Idea

A wind farm is a group of wind turbines? in the same location used for production of electric power. A large wind farm may consist of a few dozen to several hundred individual wind turbines, and cover an extended area of hundreds of square kilometres, but the land between the turbines may be used for agricultural or other purposes.

Details

Onshore and Offshore

Wind farms can be divided into three main types depending on their location: onshore, shallow offshore, and deep offshore. In a shallow offshore wind farm, the turbines are fixed rigidly to the sea bed, while the deep offshore type uses floating structures which are tethered to the sea bed.

Onshore wind farms represent a mature technology with many commercial wind farms in operation. There are a smaller number of commercial shallow offshore windfarms. Deep offshore wind farms are at the prototype stage. The wind over the sea tends to be stronger, more consistent, and less turbulent than over land, resulting in better performance, but corrosion and storms present problems.

Grid connection

Individual turbines are interconnected with a medium voltage power collection system and communications network. At a substation, this medium-voltage electrical current is increased in voltage with a transformer for connection to the high voltage transmission system. Also see Electrical grid.

Environmental impacts

Offshore wind farm impacts - noise, artificial reef

The environmental impact of Alpha Ventus, a German offshore wind farm, is being investigated by several research facilities. Some preliminary results are:

  • The noise during the building process caused whales to flee the area, but now they have returned.

  • There are reports that the installations function as an artificial coral reef that attracts mussels, sea anemones and oysters. Local fishermen hope that the fish population will also grow as a side effect.

See:

Impact on surface air temperatures

Roy and Traiteur (2010) have studied the impacts of wind farms on surface air temperatures. This is their abstract:

Utility-scale large wind farms are rapidly growing in size and numbers all over the world. Data from a meteorological field campaign show that such wind farms can significantly affect near-surface air temperatures. These effects result from enhanced vertical mixing due to turbulence generated by wind turbine rotors. The impacts of wind farms on local weather can be minimized by changing rotor design or by siting wind farms in regions with high natural turbulence. Using a 25-y-long climate dataset, we identified such regions in the world. Many of these regions, such as the Midwest and Great Plains in the United States, are also rich in wind resources, making them ideal candidates for low-impact wind farms.

Examples

The world’s first wind farm – consisting of 20 wind turbines rated at 30 kilowatts each – was installed on the shoulder of Crotched Mountain in southern New Hampshire in December, 1980. The Roscoe Wind Farm (780 MW) in the state of Texas, United States, is the world’s largest wind farm. Spain, Denmark, and Germany are Europe’s main wind energy producers; although, the largest wind farm in Europe is the Vlorë Wind Farm (500 MW) located in Albania.

Deep offshore demo in Norway

Ten kilometers off the south-west coast of Norway, Statoil’s Hywind is the world’s first full-scale floating wind turbine. Statoil will test the wind turbine over a two-year period. According to Statoil

The primary intention is not to derive revenues from the power generated by Hywind, but to test how wind and waves affect the structure. Once these answers have been obtained, Statoil can work on commercialising the concept. The goal is to reduce costs so that floating wind power can compete in the energy market.

In China

Data released by the Chinese Renewable Energy Industries Association? in January 2011 showed that China had overtaken the United States in installed wind-power capacity. China added 16 GW in 2010 to reach 41.8 GW. (From Nature, 3 February, 2011, p10.)

In Germany


Wind farm in Lower Saxony

Wind farms have been built in Lower Saxony, Germany, over the past twenty years. This project has been advanced by both left and right wing political parties. Lower Saxony is considered to be a suitable place because it is mostly rural, and flat towards the North sea. There are usually strong winds mostly from North-West.

In 2010, the first German offshore wind farm went online:

Large offshore wind farms in Britain

In July 2013, the world’s biggest offshore wind farm was switched on in Britain (630MW max capacity).

A previous record holder (in 2010) was off Kent in SE England with 300MW.

Small onshore wind farm in Scotland

See: Renewable energy in a small remote village.

In the United States

At the end of 2009, the installed capacity of wind power in the United States was about 35 GW, making it the world leader ahead of Germany but it has since been overtaken by China. Wind power accounts for about 2% of the electricity generated in the United States.

About 9.5 GW of new wind power capacity was brought online in 2009, up from 8.5 in 2008. In 2009, the additional new capacity was enough to power the equivalent of 2.4 million homes, or generate as much electricity as three large nuclear power plants. In 2010, the United States added 5.1 GW, only about half that added in 2009.

The Cape Wind project—the first offshore wind project in the United States—has received a 28-year lease from the Interior Department for its development and operation in federal waters. The footprint for the proposed project covers 62 square kilometers, and would be 7.7 km from Mashpee, on the south coast of Cape Cod, and 25.4 km from the island town of Nantucket.

The Cape Wind project envisions 130 horizontal-axis wind turbines turbines which will be sited between 6-18 kilometers offshore depending on the shoreline. At peak generation, the turbines will generate 454 megawatts, but on average they are expected to produce 170 megawatts of electricity, about 75% of the average electricity demand for Cape Cod, Martha’s Vineyard, and Nantucket island combined. Cape Wind could offset close to a million tons of carbon dioxide every year.

In the United States, Google and other big investors are “are throwing financial support behind an idea to build a multi-billion-dollar power distribution line for offshore wind farm projects”. This project is called the Atlantic Wind Connection:

See:

In Belgium

Belwind brought the largest renewable power plant of Belgium into operation on 9 December 2010. The Belwind power station in the North Sea consists of 55 turbines and represents an investment of 614 million euros. Belwind expects to be able to provide 175,000 households in Belgium with green power, thus avoiding 270,000 tonnes of CO2 per year. Cooperation between local, regional and national authorities made it possible to develop the wind farm in a record time of 3.5 years and to build it in only 15 months:

In Korea

South Korea is planning to build an offshore wind farm off with about 500 turbines. The 2.5 GW project expected to be completed by 2019, and will cost about $8.2 billion to build. Companies including Hyundai Heavy Industries and Daewoo Shipbuilding and Marine Engineering are constructing the turbines. The government is coordinating the project and putting up a large chunk of the price, but private investors will need to finance the remainder.

The purpose of the wind farm is not only to produce to add renewable energy to South Korea’s grid, but to give some of the area’s machinery makers (like Samsung, Hyundai and Daewoo) experience in building wind farms so that South Korea can become a major wind turbine exporter.

In high velocity places

Due to how wind power is generated the only way to get more power is to use places with high speed. Like the jet streams and use solutions like High altitude wind power.

References

category: energy