If you have an 8 Cubic Foot ref., or smaller, and limit your use of non LED lighting, and exhaust fans, and a good voltage meter connected to the house batteries, you can go at least 3 complete days without having the 2 battery system drop below 12.3 volts. Using solar will help, but, in the summer, we try to find shade to park in, and pretty much limits the solar output. We normally carry a 2000 watt gen. to use as it will run for 8 plus hours on a tank of fuel, and is quiet. It will run everything but the AC, or hair drier. It will even run the Micro after about 30 minutes of charging the batteries. We changed our 8 cf refer, to a sidewise 14 cf, that self defrosts every night. We changed to the bigger one for more food capacity for dispersed camping, for longer times. The only problem is the big refer is a 12 volt energy hog, and after 2 days usually need to recharge. Boondocking is the bomb and is worth all the work, for the enjoyment.