Calculate KWh Generated By Wind Turbine

Knowing that wind speeds can be modelled by the Weibull Distribution we can estimate the amount of electricity likely to be generated by a given wind turbine generator in a location with a given average wind speed over the course of a year.

Wind Turbine Wind speed distribution modelled by WeibullAnnual Electricity Output Calculator

Below is a unique free online tool from to estimate the amount of electricity which can be generated by a wind turbine with a known rotor diameter, in a location with a particular average wind speed.
nb. Click here for average wind speeds in UK locations.

Using the Wind Turbine Electricity Output Calculator

The default values in this calculator (1.75m diameter rotor, 4 m/s cut-in speed etc) correspond to the Windsave 1000, a domestic roof-mounted wind turbine generator currently sold through B and Q.

If the average (mean) wind speed in your location (at 10m above ground level) is 5 m/s then it is probably no more than 2 to 3 m/s on your roof because of turbulence and obstructions (trees and other buildings etc).

The calculator above predicts generation of 990 kWh at average wind speeds of 5 m/s, but just 6 kWh at an average of 2 m/s and 119 kWh at an average of 3 m/s. This explains why so many consumers have been disappointed with their micro wind turbines. There is nothing wrong with the wind turbines per se, it is just that they are being located in sites with insufficient wind.