Re: Solar power for a pontoon boat cabin
I built a teardrop trailer a few years back, and some of us guys used a combination of energy sources.
Cooking- It's propane all the way. Heck, if you're not going out for days at a time, you can even use the little bottles--not the huge tank. Easy to store, easy to shlep, and not expensive. Of course, you'll get a little 2-burner stove, but keep your eyes out for an oven too! They make them (I have an old Brinkmann), and there's one company that sells a combo stove AND oven in one piece. People don't really think about it, but the convenience of an oven is AMAZING for a lot of your cooking.
Refrigeration--The extreme coolers are the best. These 5-day, 7-day coolers are spectacular and very inexpensive. Throw your ice and food in there and 5, 7 days later, you still have ICE in there.
Lighting--some of us rigged cheap Harbor Freight solar lights, the kind you would use for your patio/garden. But how much light do you need on a small boat anyway? Get lamps that take C, D, AA...WHATEVER battery size...and you're good to go. Get yourself some rechargeable Ni-MH type batteries and you're good to go forever.
TV/DVD/Etc.--Just one 12V deep cycle marine battery, a battery charger, and a cheap DC to AC inverter (a couple of hundred watts will do the trick). I'm assuming you have a 12V on the boat anyway, but get one dedicated just for this.
Heating--They make very safe, very cheap propane heaters these days, ones that take the same little propane bottles that your cooking stove uses.
Cooling--Look, this ain't the Queen Mary, and we can't have EVERYTHING, can we?