Earlier quoted context omitted.
Dual source heatpump + Solar + battery + propane generator might be OK. The batteries would need to somehow be kept warm though. (The solar and battery are there to stretch out the propane supply until the delivery truck gets past whatever road blockages exist, and then addresses the inevitable shortage cause by the electricity going out.) Of course, an 80% efficient wood stove costs a small fraction as much as the a…
Too bad few backup generators have the capability of dumping their heat output into the home via coolant loops or exhaust heat capture.
Exhaust heat is fine in theory but HN would be screaming bloody murder if even one person died from CO as a result of a shoddy install or cracked heat exchanger so it's basically a nonstarter if you're a big juicy lawsuit target like a business. While there's nothing fundamentally different from a forced hot air furnace the novelty factor makes fending off the ambulance chasers more expensive than it's worth.