Though the turbines surveyed by Encraft did generate enough electricity to light an energy efficient home, on average "this still only represented 5-10% of the manufacturer's claims" regarding output. The best performing turbines surveyed could generate enough electricity to offset the amount of electricity needed to manufacture them in two years, while the worst ones could take up to 40 years to do so.
For comparisson, the BWEA states that for industrial scale wind turbines, the actual power produced by the turbine is about 30% of its theoretical maximum capacity.
Small-Scale Turbines Inappropriate For Many Locations
While Encraft's managing director did say that in some locations home wind turbines are still a good investment, in the majority of locations this isn't the case: "Sadly, an average semi-detached house, like the areas where most people live, where there are obstructions like trees and buildings, are poor locations."
via: The Guardian
For the record...from the access to the report I have, the inclusion of this picture is not meant to be an indictment of this specific wind turbine (some turbines performed better than others), but is just representative of the scale of turbine discussed. Photo: thingermajig via flickr
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