We do boondock quite a bit, We have 360 watts of solar, but in the summer, we park in the shade to keep cool, so not full output except in the morning or late evening. After the first night, the batteries need more current than the solar will furnish. We will run a 2,000 generator during the evening for TV/sat/DVD watching. If it is really hot, we will start the onboard generator to run the ACs and stay inside. You can add more batteries, but you will have to recharge them sometime, and the more you have, the longer it takes. At 12.0 volts, your batteries are essentially dead. Discharging batteries this far, over and over again will kill them pretty quickly. If you are going to boondock, you really should get some way to monitor your house battery voltage, and start recharging at not less than 12.3 volts, to help the batteries live longer.