Solar Battery Charger

[Cstar]

We bought a new car recently, the salesman let us have a small solar device kept in the window to keep the car battery charged. It is about 14'X10" and attaches to the window via suction cups and plugs in to the cigarette lighter.

Would/could such a device be used in our Airstream this winter? Could we place it in the window that gets the most sun and plug it in to one of the 12 volt outlets?

Corky

[sfixx]

The rule of thumb given in the Moeller's book RV Electrical Systems is that you should have a 50 watt solar panel for each 100 amp hour battery. Your dash top panel is probably barely a trickle charge and would take more than a week of full sun and no load to charge a deep cycle battery. If you are thinking about using it simply as a battery maintainer you need to be sure that it has a built in regulator so that it will not over charge the battery. Would it make sence to disconnect the battery from the RV anyway to be sure that no phantom loads are present? For more info check out this website by the authors of RV'ers Guild to Solar Battery Charging:

http://www.rvsolarelectric.com/

I've requested their free info kit for determining panel requirements.

Good luck,

steve

[Tom Nugler]

Hi Corky,
If that panel is from VW it is indeed a trickle charger. They do a halfway decent job of keeping a car battery around 12.5 volts, which satisfies our delivery requirments. As far as output the best I've seen them put out is about 300 milliamps. There is no regulation but I'm sure no battery has ever been overcharged by one.
I've got 4 or 5 laying around and have been comtemplating wiring them together, mounting 'em on a piece of plywood and setting it on top of the AC unit.
Good luck, Tom.