I might be a bit biased, but how about using the generator budget and putting it toward roof-mounted solar instead.
For myself, I certainly considered it, and may still eventually do it, but there are some drawbacks that have kept me from it with the camper I have now.
A) I like to park in the shade when I can. I do like the desert, where there is plenty of sun, but I have a surplus parachute that I like to spread out over the camper. It gives me a nice large shaded area (awnings on all sides basically) and by spacing it up off the camper roof a bit, keeps the camper a lot cooler.
B) I have a camper van. I.e., not a lot of rooftop real estate. I could easily get a 180w PV module on the roof. If I relocated or eliminated the 14" roof vent I might even squeeze in two - but even 360w wouldn't be enough to run heat or a/c so I'd still need the generator anyway if I wanted to run big loads like that.
You could get a pretty significant solar system for the cost of a generator.
Not quite. My generator cost $500. You wouldn't get a large solar system for $500.
Sure, a small solar setup would be plenty to keep up with a DC fridge, but the one I have is a 3-way, and it draws a LOT of amps on DC. Far, far better to run it on propane. I thought about ripping it out and replacing it with a DC fridge, but this one works fine and since it costs about 10 bucks to fill the propane tank once a month or so...it would take years to amortize the cost. It's the smallest, simplest unit Norcold makes (model 323) and doesn't have an electronic control board to fail, so the fridge is very unlikely to fail and need replacement. If it does, I'll reconsider the 12v fridge option.
The battery doesn't get used for much. It runs the water pump, netbook, DVD player and some lights and fans and also occasionally recharges AA batteries (once a month or so for toothbrush and shaver) and the 18v Ryobi batteries for my portable power tools, which don't get used much except the flashlight.
So, $500 (or more) worth of solar to keep all the batteries charged is a little overkill, whereas $500 for a generator + the gas to run it once or twice a week when in the field does the same job, but also gives me the ability to run bigger loads if need be.
And it's not just the solar, to store the harvested watts I'd need more battery as well. One 100ah battery isn't much really. Two would be better, so there's some more additional cost for another battery as well as wiring and whatnot.
Solar is nifty, and at some point I might add it to this camper, but I'd still carry the generator anyway...so do I really need the solar? Also to consider in my situation, is that if I'm on the move or moving every couple of days, then the truck's alternator keeps the battery charged and I never need the generator. I only use it when parked at one spot for more than a few days.
Then you have clean, silent, reliable power that's automatically doing its thing at all daylight hours.
Not really. PV modules (solar panels) don't put out much unless they are getting hit with full direct sunlight. Generally, fixed flat mounted panels can be expected to put our full power for 4-6 hours a day. Overcast cuts down the output by as much as 90%, and any shade at all - even on one cell in the whole module - can cut the power output to almost nothing. But even that's a bit misleading, since PV modules don't put out full rated power when they get hot, and since they are dark colored and pointed at the sun, they are usually hot. So figure they'll normally put out 80% of rated power for 4-6 hours per day.
That way you don't have to allocate space for generator storage or worry about fuel, fumes, noise, or convenient theft.
Yea, true. I solved the space and theft issues by building a metal box on the back of the camper to hold the generator, which can be locked shut for transport, or locked partially open for cooling when the gen is in use but still make theft somewhat difficult.
Fuel, fumes and noise...those are still issues.
