The UK has the best wind resource in Europe, an asset that has the potential to provide a considerable proportion of the UK energy needs in years to come. The DTI estimates that by 2050, up to 30-40% of UK's electricity generation could be produced by small and microgeneration technologies, including 6% from small wind energy generation.

Siting a small wind turbine

The output from a wind turbine is highly sensitive to wind speed. It is essential that turbines should be sited away from obstructions, with a clear exposure or fetch for the prevailing wind. Wind speed also increases with height so it is best to have the turbine on as tall a mast as possible. The wind speeds up significantly near the top of the hill and the airflow should be reasonably smooth and free from excessive turbulence.

Excessive turbulence causes fatigue damage and shortens a turbine's working life.

In practice, especially for very small machines, which need to be located near to the user, ideal siting will not be easy. As far as possible though, keep away from local obstructions such as large trees and houses, or use a taller tower to ensure that the turbine is well above the obstructions.

Before considering the installation of a wind turbine the potential site should be assessed. Initial indications of wind strength and direction can be obtained by observing the deformation of vegetation and trees, and in many cases the user may already have a good feel for the winds in the locality. However impressions can be deceptive.

You can get an estimate of the annual mean wind speed for a given location by entering the OS grid reference into the UK wind speed database. A more reliable way to evaluate the wind resource is to take regular measurements over a period of several months, preferably a year.