Originally Posted by jhawk
Sounds like if we can't get an electric site I'm taking my long johns to sleep in. I don't want to kill both of my batteries before summer even gets here! Thanks for the info, I didn't realize how big a drain the fan would be.
We would dry camp for 8-10 days each year at Lake Tahoe (6000ft elevation) in our PUP (single battery). We used sleeping bags, but still needed to keep the PUP thermostat at 50 degrees for reasonable comfort. Some years, we needed to run the heater at least half the nights. You could tell by the lights that our battery was being discharged more than I would like it to be. It became appararent that the real limit on our endurance (for our style of camping) was the battery.
Things that are really worth doing:
1) Replace any lights that get used frequently with LEDs. I hated being the light police (to save the battery). By using LEDs, the lights are no longer a significant load. LED flashlights and/or headlamps for everybody, and a gas lantern at the picnic table further reduce battery use.
2) On my first PUP (didn't have a hot water heater), I replaced a broken faucet with a gooseneck, and replaced the electric pump with a nice foot pump for sailboat galleys. I like that arrangement much better, and could access my water supply regardless of battery charge. It would be a little trickier to redo the plumbing to keep water in a hot water heater and/or pressurize a shower - probably need electric there. But foot pumps for the galley are so nice....and they keep the gray water bucket from filling up so fast.
3) Again, the simplest alternative if the battery bank is not sufficient to run the heater as desired is to use a portable catalytic heater. It's not as convenient as a large battery bank, but setting up and monitoring solar panels or carrying and hooking up generators, or just plain monitoring battery charge is not all that convenient, either.
I've become a firm believer in keeping my camping just as simple as I can with a reasonable comfort level. The simpler the systems are, the more time spent enjoying the outdoors instead of setting up/packing up and systems monitoring.