Hi Thomas,
The correct choice of prop is super critical for the average wind velocity at any given site. Grabbing at all that air running past at faster than the average speed your prop was designed for won't get you any more power. You'd have to be willing to go up there and change the prop every time the airspeed went higher. Then, if you do that, you'll lose power production when the wind fell back to normal. Check this propeller efficiency chart. Your prop is probably peaking out on power production at +/-28 mph, so ratioing that propeller curve there, its efficiency is falling at around 33-35 mph to Zero. If you changed to a prop with Hi eff at 35 mph, when the wind is back around 25 mph, you'd only be at 55-60% of optimum juice making capacity, so you'd be up there changing the prop again. I believe the gen has an internal brake that starts kicking in at 33 to 35 mph, otherwise the prop would vibrate and maybe fly apart when it hit 45-50 or the voltage would get too high at those rpms and start burning through the insulation.
I'm a rotating equipment engineer and don't know much about grounding such that I'd want to give you possibly bad advice, but I have found this information for what may cover some of your questions. Read this page on lightning arrestors, check the diagram for the PV installation, and see you think any of it might apply to your situation. I can point you to an engineering Q/A site where you might be able to get a good answer.
http://www.eng-tips.com Register there and go to the Electrical Engineering and Motor Forum. Post your question. Usually the advice is excellent ..and reasonably fast too, although you might want to wait to see if some "alternative" suggestions come up. Then come back here and tell me what they told you.
