In any case, widespread use of wood as fuel is not feasible in major cities because of the pollution it produces and in the lesser developed world, it is use of wood for cooking etc. There are too many people on the planet to be sustainable at any reasonable standard of living. As long as the left denies this, it is doomed to irrelevancy. You should perhaps close down all your southern cities and move the population to rainy Seattle and the norther wet coast. I don't see why much of what Gar says does not apply to cold climates.
Insulation does cut down on fuel costs.
I use mostly wood heat as do many around here. I don't have time to do a decent essay on this. 25 years ago.