Understanding turbine wattage ratings

[ian]

Hello again. I assume that in determining the wattage for any particular turbine there is a relationship between its diameter, average wind speed and its generating capacity, found within the coils and magnets, etc, but how is this number calculated? I'm thinking of building the Hugh Piggott's 8' axial flux.

Thanks for your time, Ian.

[vawtman]

Ian,I recommend you purchase Hughs book.All the formulas are in there.Very good reading.

[paradigmdesign]

Usually they rate turbines by a specific output at a given wind speed.  i.e. a 5kw genny rated at 25mph would have the same sized blades as a 10k that was rated at 31.1 mph.  So the lower the wind speed in the rating, the better.  Anyone that rates there gennys much past 26 mph, is in my opinion, inflating there numbers, and overall output of any given design.