I have looked at them from other manufactures before. Not a bad idea if you camp where you get enough wind to power them. We look for spots out of the wind for the most part.
Even though they don't have a mounting solution other than rails, no doubt you could hook it up in some way to work.
I wonder how tough they are, and how much you would have to worry about damaging them during transport.
I also wish they had more info on charge rates at different wind speeds.
All in all, a great idea though. Any idea that can keep those batteries from draining can only be good.