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Wind Turbine Power Calculator


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Note 1: Energy output results from calculation programmes like this may differ slightly from the results given by manufacturers.
Note 2: Power curves are found by field measurements which may be uncertain. Therefore these results should be interpreted with great care, as the may be some +/-10 per cent uncertainty in these measurements.
Note 3: Turbine manufacturers may have site specific turbine models available which are not listed here.
Note 4: The site data below was not chosen as being particularly suitable for wind turbines, but was taken directly from the anemometer locations used in the European Wind Atlas. In the case of e.g. Frankfurt (D), one may e.g. find locations on neighbouring hills to the South with twice as high an annual production as you would get at the airport where the anemometer is located. In the case of e.g. Northwestern Ireland, sites on rounded hills in the area may yield 20-25 per cent higher energy output.

You may experiment by changing the figures in the example below. You can fill in any box, except the result boxes marked with an asterisk (*). After changing data, use the tab key, click the Calculate button, or click anywhere on the page outside the field you have updated to see the results. Click on the question marks for help. (If a plot windows disappears, it is probably hidden behind this window).


Site Data
Air Density Data
°C temp atm altitude (=kPa pressure)kg/m3 density
Wind Distribution Data for Site
Weibull shape parameter
m/s mean =Weibull scale parameter
m height, Roughness length m = class


Wind Turbine Data kW
m/s cut in wind speed,m/s cut out wind speed
m rotor diameter,m hub height




Site Power Input Results
Power input* W/m2 rotor area
Max. power input at* m/s
Mean hub ht wind speed* m/s
Turbine Power output Results
Power output* W/m2 rotor area
Energy output* kWh/m2/year
Energy output* kWh/year
Capacity factor* per cent


Wind Turbine Power Curve
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...kW









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Cost by Lifetime