Hey Guys,
Thanks for all your input.
I have been out of town for a few days, and I come back to PAGES of new comments on this thread!
I was on a road-trip with a few Citicar buddies. The one guy, Rich, has a Generac generator which he got for free because the inverter on it is busted. It's a very compact 3K brushless dc generator. It also runs off propane. (Which is about as clean of a fossil fuel as one can burn)
I think we are going to track down some tech information on this generator, and see if we can find what the output DC voltage is on it. Then I would only need to figure out how to convert that to say 56 volts or so for charging a DC system, and control the amperage.
On the drive home from the Citicar gathering, I saw a great motorcycle with both a sidecar AND towing a teardrop trailer!
You can't see the sidecar too well, as we were on the wrong side, but I made sure to give the guy a big thumbs up as we passed him.
A smaller version of his teardrop trailer would be perfect for a small generator setup!