The natural gas requires electricity (it's a forced-vent furnace) but the coal doesn't give a ****. It's just a pain in the ass to get started so I like to keep it going continuously to both supplement the NG furnace and be on 'standby' if the power ever goes out. And yes, it's awesome sitting down in the living room after working outside in this stuff. Also very glad I decided to build a new coal bin in the basement vs. the outdoor one, that'd suck right about now.
I bought, but haven't yet installed, an on-demand NG water heater...the electric one is costing me ~$50-60 a month by itself, and the NG unit was $420, so in theory it should pay for itself within a year once I get it installed. It also requires electricity but it's a very minimal draw; with a car battery and an inverter I should be able to run it for the length of any power outage I've ever lived through.
Just converted the kitchen range over to NG as well so in the absence of power I can still cook stuff too. :flame: