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Wind energy has come of age. Unlike conventional fuels, wind energy is a massive, indigenous power source, and it is permanently available. It has no resource constraints: the ‘fuel’ is free and endless. On top of this, wind energy entirely avoids carbon costs, and suffers from zero geo-political risk associated with supply and infrastructure constraints, or energy dependence on other countries. Europe has taken the lead in technology development and consolidated its position as global market leader. “More installations exploiting wind power can help to plug the growing gap in European electricity supply and at the same time dovetail with the Lisbon Strategy providing the EU with high-tech world-class technology”.

Introduction to Wind Energy the Facts, DG TREN, European Commission, May 2004

State of the art technology

In contrast to the windmills of the 19th century, a modern power generating wind turbine is designed to produce high-quality, network frequency electricity whenever enough wind is available. Wind turbines can operate continuously, unattended, with low maintenance, and some 120,000 hours of active operation can be expected over a design lifetime of 20 years. By comparison, a typical car engine has a design lifetime of the order of 6,000 hours. Since the early 1980s, the capacity of an individual turbine has increased by a factor of over 200. Generation costs have declined by 80%. Modular and quick to install, wind turbines range in size from a few kilowatts (kW) to 5,000 kW. Wind turbines are highly reliable, with operating availabilities (the proportion of the time in which they are available to operate) of 98%. No other electricity generating technology has a higher availability. Many developments and improvements have taken place since the early 1980s but the basic architecture of the mainstream design has changed little. The rotors of most wind turbines face into the wind, and actively ‘yaw’ to follow changes in wind direction. Wind farm developments can be as small as a single turbine or as large as several hundred megawatts (thousand kW). Sited in an area with a good wind resource, a single 1 MW turbine can power 650 households.

Key advantages of wind power

• Clean energy - no resulting carbon dioxide emissions
• Low cost – at optimum locations, wind can be competitive with nuclear, coal and even gas, on a level playing field
• Rapid deployment – modular and quick to install
• Fuel is free, abundant and inexhaustible
• Provides a hedge against fuel price volatility
• Security of supply - avoids reliance on imported fuels
• Provides bulk power equivalent to conventional sources
• Land friendly - agricultural/industrial activities can continue around it

The Global Wind Power Industry

• Employs around 120,000 people
• Has an annual turnover of more than €12 billion
• Has been growing at an annual rate of more than 30% over the last 8 years
• Meets the electricity needs of more than 25 million households
• Is concentrated in Europe, which accounts for 70% of total capacity
• Over 85,000 wind turbines installed today
• Over 58,000 MW of installed capacity

Environmental Integration of Wind Turbines

Most wind energy projects require an Environmental Impact Assessment (EIA) under national and European Law, which allows the full details of environmental costs and benefits of a project to be scrutinized in the public domain. Whilst wind energy is a clean technology, it is not without impact on the environment. The main issues are:

• Visual impacts: wind turbines are a relatively new feature in the European countryside and have an impact on amenity. Consultation with, and acceptance by, local communities is essential. In order to maintain public acceptance, wind farms need to be designed in such a way to minimise aesthetic and amenity impacts.

• Sound emissions: modern wind turbine designs have improved to the point where mechanical noise is insignificant, so the issue is now aerodynamic noise from the turning blades. At a distance of 300 metres from a 1MW wind turbine, the expected sound level would be 45 decibels (dBA).

• Birds: collisions with turbines have been an issue at some older wind farms sites built in the 1980s, especially in the Altamont Pass in California, a result of poor siting, and out-moded turbine and tower technology. Subsequent experience in Germany and Denmark shows that such effects can be avoided by responsible planning practice. Proper siting of turbines is important if adverse impacts are to be avoided. The negative impact on birds must be placed in context. 99% of the threats to birds are human related, from habitat loss to industrialisation, the over-exploitation of natural resources, hunting, the pet trade, pollution, etc. Habitat loss is the single greatest threat to birds, and 12% of the world’s 9,800 bird species face extinction.

Development Potential of Wind Energy

The wind power industry has been growing at an impressive rate, within and outside of Europe. The latest industry figures for the EU wind energy market show that cumulative wind power capacity increased by 18% to 40,504 MW (megawatt) at the end of 2005, up from 34,372 MW at the end of 2004. 6,183 MW of wind power capacity were installed last year, representing a wind turbine manufacturing turnover of some € 6 billion.

Wind power has the potential to make a major contribution to the world’s increasing energy demand. EWEA projects that 180 GW of wind energy could be generating 425 TWh per annum by 2020. In the process it would save an annual 215 million tonnes of carbon dioxide by 2020. Wind Force 12, a publication by the Global Wind Energy Council (GWEC), EWEA and Greenpeace, shows that 12% of the world’s electricity can be supplied by wind power in 2020 if political and policy changes are being pursued, so that technical, economic or resource limitations are minimised.www.erec.org