The furnace is a furnace, and we really don’t use it all that much. It’s usually off during the night and is used mostly to warm things up in the morning. My guess is that it is only a small part of our energy shortfall. I’ve toyed with the idea of replacing it with a Wave-type catalytic, and may do that someday. But for now we’re going to leave the furnace as-is.
During our first few days (nights?) with the camper last summer we noticed this shortage of power when camped in a very wooded campsite for a few days. Of course there the solar panel was contributing very little if anything to the cause due to lack of direct sun. We like camping in wooded areas and are not about take that out of our repertoire
And then we have cloudy days, right? Could even be a few in a row. Can’t make solar power on cloudy days… at least not much.
Possible Solutions: 1.) more solar panels 2.) buy a generator 3.) plug into the grid more often
Discussion: More solar panels may help on ideal sunny days, but what happens on cloudy days, or when we’re camped under a forest canopy? More solar is out.
The generator idea means we’d have to find a place to store it on-board. Then there’s the necessary gasoline… where do we put that? And furthermore, I’ve been one of the first to look down my nose at people with generators. You know… those "generator people" out there… loud obnoxious machines belching smoke and fumes and noise… I can’t stand it. And they’re probably just watching television when they ought to be outside communing with nature. Those, those… generator people!!
Plugging into the grid more often… in our case, it’d be every 2nd or 3rd night. The on-board charger would top off the battery just dandy and we’d be good to go for another couple nights. Hmmm. This might be the solution… except that… we didn’t buy this rig with the intention of going to full-hookup RV parks or KOAs or fancy plug-in campgrounds. We bought it so we could be off the grid, offline, for days and days in a row… lost up some lonely dirt road near the top of a mountain… a small clearing next to a babbling brook or splashing stream... places people rarely go. That’s why we bought it. So, NO, we’re not going to plug-in more… or at all if we can help it.
Our Solution: We put all this information into a couple big computing machines and let it grind away for a few days. We talked. We debated. We played “what-if” games, not to mention a few hands of "gen"rummy. And we decided to buy a generator.
This is how we’ve used it the first two times during our Mojave NP trip: Every 2nd or 3rd morning, when the battery is down to near 50% (12.2 volts resting), we fire up the genny and plug it into the 120v input on the camper. The on-board 3-stage charger begins to “bulk” charge the battery… throwing in a heavy dose of amps and volts (I don’t know… 5?, 6?, 7?, solar panels worth of juice?). After just an hour the battery is at 60% to 80% of full charge and we shut the genny off, stow it, and let the sun (and the truck, if we’re driving that day) finish charging the battery during the day. It all works as I’d hoped… even better than I’d hoped.
How about carrying that extra gas? Won’t have to very often, if at all. As I said above, the genny’s gas tank holds a little over a half gallon, which I estimate will last about 6 hours at it’s easy running pace. That alone should last us a couple weeks at the hour every couple days rate. I did pick up a 30oz. MSR aluminum fuel bottle, the kind backpackers use for stove fuel, and found it fits snugly and securely in the vented propane compartment. But really, we stop for fuel every day or two anyway, and it’s an easy thing to top of the generator tank at that time. Keep it simple.
So bring on the cloudy days and the heavily wooded forest campsites. We’re ready for ‘em. And we won’t have to plug in to the grid, ever.