How often/much do you realistically need to heat a house with high, quality, modern insulation? Does your house have triple-paned windows, a vestibule for each entryway, well insulated walls, attic, and roof, etc?

Also if we're talking about heating, there's also the possibility of geothermal heat pumps, which seem to work everywhere, and while they have a high one-time capital cost but I'm pretty sure can more or less keep trucking along providing unbelievably cheap heat pretty much forever - even if you have to replace components, you probably won't ever have to redig the shaft again, which is a huge factor in the cost.