DC is only marginally safer than AC. at 220V both AC and DC will easily kill you. At lower voltages you run into serious I^2R losses.
Being stuck in a cave is a good thing in this case, as the DC wiring won't burn my house down. You're trading one safety (which doesn't actually exist) for another. With DC wiring you'll run into instant problems with being able to control the current. Ever seen a typical switch? Rated for a nice line voltage at AC and a borderline useless voltage at DC, or having a disconnect capability of the normal full current at AC, or would weld it's contacts at a really low DC current. If you think you can just not swing the power back and forward and you've made things safety then you have a lot of learning to do. Safe DC installations are even harder to achieve than safe AC ones.
Also I'm basing my comments not on what was, but rather on what is. If you're banking on the future, more power to you. I hope it works out well for you. But given the cost of insitu house re-wiring that's an expense far greater than the cost of an inverter so I'll let you be the guinea pig for that concept.