If you’ve ever asked yourself, or want to show someone else, how a wind turbine works, check out EWEA’s easy-to-use interactive tool.
It allows you to play with the three main variables that determine how much electricity a wind turbine can produce:
The wind speed: Stronger winds produce more energy. Wind turbines generate energy at wind speeds starting from 4 metres per second (a gentle breeze) up to speeds of 30 metres per second (a violent storm). Over 30 metres per second (which happens rarely), the turbine is stopped from turning.
The blade radius: the larger the radius of the blades, the more energy can be produced. Doubling the blade radius can result in four times more power. Today’s largest onshore turbines can have a rotor diameter up to 127 m – longer than a football field.
Air density: influenced by altitude, temperature and pressure. High-altitude locations have lower air pressure and ‘lighter’ air, so they are less productive turbine locations. The ‘heavy’ air near sea level drives rotors relatively more effectively.
By Elke Zander ( ewea )
[mappress]
Source: ewea, December 22, 2010