Wind Turbine Power Calculator

Calculates the power of a wind turbine from size, wind speed and air density. The radius is the length of a rotor blade. The wind speed refers to one point in time, not to an average speed. Air density, which is the mass of air per space, depends on air pressure, temperature and humidity. 1.2 is a good average value at sea level (air density calculator in German: Luftdichte). The efficiency factor tells, which part of the wind blowing through the area spanned by the rotor blades is converted into electric energy. The theoretic maximum for the efficiency factor is 16/27, respectively 59,26 %.
Please enter four values and choose the units you want. The fifth value will be calculated. The formula for the electric power is P = π/2 * r² * v³ * ρ * η, one watt is calculated as 1 W = 1 kg * m² / s³.

Example: an offshore wind turbine with a radius of 80 meters at a wind speed of 15 meters per second has a power of 16.3 megawatts, if air density and efficiency factor have the given values.

The most important factor for a high power is the wind speed, which goes into the calculation at the power of three. Radius, respectively rotor blade length, goes into calculation squared, because the area through which the wind blows counts. The density of air is the higher, the higher the air pressure is (the lower the position above sea level), the colder and dryer the air is. Shape, number and orientation of the rotor blades contribute to the efficiency factor.

A three-bladed wind turbine with a radius of 58 meters. With a wind speed of 10 meters per second, this has an output of around 2.5 megawatts. This wind turbine was built in 2015 and has a nominal power of 4.2 megawatts.

Radius r:
Wind speed v:
Air density ρ:		kg/m³
Efficiency factor η:		%
Power P: