There is a product at jademountain.com (and other places, I'm sure) that is called the
"solargizer". I knew the guy that invented this thing and it is very impressive. I was
involved in some testing on it in the military some 7-8 years ago and it works great.
If I didn't have a house full of OPTIMA batteries I'd have a solargizer. Optima
batteries can't make much use of it because it is already a recombinant design. You
know, come to think of it, a solargizer would make a good fathers day gift for pops
and his SOB motorhome...hmmm.
Ralph