This is NOT a recommended configuration !
Interesting writeup of an experiment the cadets at the U.S. Naval Academy tried back in the early ’80s… Put a wind turbine on the top of the mast and us it to power batteries to run the boat.
Seemed to work, but the company nixed it for safety reasons… the turbine is not designed for the "back and forth" motion that it would get at the top of the mast, and could be dangerous (blade failure, etc.).
Interesting read (and idea)… see, this electric power stuff has been around for a while 🙂
Thanks for the pointer from the Backyard Boatbuilding mailing list.