Dear Bill, If you could make a prototype PMA that makes 48 volts cut-in when it's spun at 30 RPM, that would be very useful, whether you end up happy with your VAWT design or not.
I'm not allowed to have a HAWT where I'm at, and frankly, I can't see any way to improve it. If I can move to the country someday, I will copy the otherpower HAWT exactly. This leaves VAWTs, which may have some room for improvement...
Windstuffnow.com Ed put a Lenz2 on his roof and got a small pic in Popular Mechanics(?), but I have heard that a house mount puts a vibrational buzz through the entire frame. I'm not saying it cant be fixed (I've seen large machinery sound-isolated from a ships hull) but I'm just letting you know ahead of time what you might be wrestling with.
I think VAWT's have some similarities with water wheels (Google cameroon water wheel). Since their water wheel had very significant torque, they decided to go with a large diameter/high-pole-count PMA (expensive) instead of gear-up.
If the rim speed is about 90% of wind speed, you can calculate the diameter of the VAWT relative to average wind speeds at your site to get your target RPM's. The way then to add more torque is to make it taller to add more swept area. This can get very unwieldy. The Jay Leno VAWT was as tall as a 2-story building (dont remember the brand), and the direct-drive PMA had a fairly large diameter to get a decent magnet speed.
Another choice is to make a very large diameter VAWT (in order to increase swept area, but results in slow axle RPM's in the same wind speed) and use gearing to speed up the PMA, a completely different can of worms.
Once you've cruched the numbers, a tower and a HAWT start to look pretty good.
Sometimes a new blood pressure medication results in a profitable blood flow to other areas (Viagra) so your VAWT design exercise may result in some useful data even if it doesnt reach your particular goals. Best of luck!
