I've been using a PV panel (75 watt Solavolt) for over ten years to
charge my deep cycle house battery and it has worked out very well for
me. Even on cloudy days it will top off the battery by mid day. I am
running a stereo, subwoofer w/ 200 watt amp, 600w inverter
(occasionally), Propex heater, cabin lights and an iPod.

You may want to make a list of the devices, run time and amp-hours to
get a general idea of the battery capacity and charging ability of the
PV panel. Size accordingly. There are online calculators to make this
task easier. see: <http://www.mrsolar.com/pdf/rv/rvassistance.pdf>
Also, try googling "solar electric".

Keith O