Where wind turbines may be erected , is set in the land use plans of local and regional plans of counties or planning communities . These plans have called for priority or suitable areas for wind turbines.

The conversion of wind energy, that is, the existing kinetic energy in the moving air to other forms of energy takes place by the drive of wings. However, only a part of the mechanical wind energy is converted .

The available power in the wind is: Pwind = 1/ 2 * RAV3

r : air density in kg/m3

A: swept area in m2

v : wind speed in m / s

It can be seen that apart from the rotor surface is essentially the supply of wind for wind use is crucial. Doubling the wind speed is an eight-fold increase of wind power . How much power can actually be extracted from the wind maximum was calculated by Betz for the first time in 1926.

The Betz power factor is: cp = Betz (about 59 % of wind power).

Until conversion into electricity to more losses result :

Aerodynamic by flow around the vane ends , further by converting mechanical losses in the drive train , such as the gearbox and electrical finally , so that the so-called power coefficient which is determined in a curve for various Windgeschwindigeiten reaches maximum values ​​between 40 and 48%.

Modern wind turbines with power 10-1500 kW reach their rated power depending on the make at 10 - 16 m / s, a switch between 2 and 4 m / s and 20-30 m / s wind speed for security reasons . It therefore knows the specific annual average wind power in W/m2 at hub height, so can be used for efficient windmills with an average efficiency of 33-35 % can be expected . This can then be roughly estimated the annual energy output in kWh.

Wind turbines can be of a rough target price of 1000 EURO per 1kW

Power (!) Go out, but for a system with 1 MW rated power is usually

a purchase price of approximately € 1 million. The points are logistics costs (20% of price)

Rotor blades (25%), cable with gearbox and generator (30%), Tower (20%) and foundation

(5%).