small wind chargers are unpleasantly noisy from what I've seen... If it isn't blade noise, it's bearing noise, or the whine of the generator itself generating. My best friend and I many years ago made quite a few in our spare time in his shop. We used automotive generators, and various permanent magnet motors, etc, and carved the blades out of wood, often putting serious time into getting the twist right.... an interesting calculation. None of them were large. We even built a 6 blade VAWT where the pitch of the blades changed so that they were always at an optimal angle of attack as they went around the circle..... basically "close hauled". If the wind was from the north for example, and you were starting from the 6:00 position, moving clockwise the leading edge of the blade would be pointed slightly to the west, changing to the opposite tack as the blade moved toward the 12:00 position, and on to the 3:00, where it would again change tack. The angle of attack changed constantly. The mechanism we used to do this was fairly complex. I don't have any drawings or photos unfortunately... that was over 30 years ago, and we just did it for fun. Not practical due to the complexity, it used a cam system like a hay rake, with cam followers in a track, but it was reasonably efficient........ and a great show and tell item. Bob died in a shop accident 12 years ago, and I lost track of many of our projects.
My dream for a wind charger was a tubular, venturi type of thing with no moving parts in the generator. A grid would impart a static electrical charge to the air molecules which would then pass through a coil creating a current. It was well beyond my pay grade, but not beyond my imagination ;-) I just recently encountered an article about just such a wind charger. It used a mist of charged water droplets. Needless to say the violent thunderstorms of early summer were what inspired my idea.
On a boat, solar, hydro, and wind all have a place. However under weigh it seems silly to use a wind charger..... at anchor is where they seem best suited. It would be nice to have them floating on their own well away from the boat so you didn't have to listen to them.. every bit of noise they generate is going to be transmitted throughout the boat. Obviously not practical ;-(
Perhaps a floating VAWT could be made self stabilizing due to the gyroscopic forces. If there were two VAWTs, one above the other running concentrically in opposite directions, the generator fields rotating in one direction and the armature the other direction, gyroscopic precession would cancel itself out and the thing should sit vertically due to the forces........ or so it seems to me. Any child who has played with a gyroscope knows if you apply force to tilt it at one point, it reacts 90 degrees past where you applied the force.
H.W.