Propane
Nat gas is grid dependent, outages, repairs, backhoe joe diggin into 3 miles up the road. Etc
If youre sitting on a 500 gallon tank of propane, youre set for a while.
This. Going with natural gas puts all your eggs into the “grid doesn’t go down” basket which is exactly the situation you’re trying to game for. I’d go propane with a dedicated tank.
