My wind speed is 5.7m/s at 10m. I am on the top of the North Downs but do have some trees and houses around the turbine. We will hopefully make 3-4000 kwhs a year here.

On paper I should make 14000 kwhs but this is calculated without factoring in the roughness for terrain around my property. This turbulance is the biggest factor.

What is the terrain like around you turbine location?
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Stuart