Wind Generators – Bigger is better
When it comes to getting the most out of wind generators it is very important to remember that power increases by the square of the blade diameter and by the cube of the average wind speed. If you want more power – increase that diameter.
The generally accepted formula is annual output (KWH/year) = 0.01328 (Diameter^2) (Velocity^3). So with all else being equal, if you double the diameter of the blades you will get four times as much power. Assume 8 MPH wind speed and you have a choice between 10′ or 20′ diameters. the 10′ size will generate 2300 KWH per year. The 20′ size will generate almost 9200 KWH.
Now, you may not think you have control over the wind speed but you actually have some control. I’ll save that discussion for another post.