I've been heating with wood for the last 20+ years. 'Course "heating" here in Tucson is a lot different than you Northerners experience.

Double glazed windows, 2" foam sheeting under an inch and a half layer of stucco, 12 inches of insulation in the attic does make a bit of difference.

We have a DutchWest wood stove which is probably the most efficient and cleanest stove available (uses a catalytic element in the flue) and a cord of wood lasts about three years.

We've got a natural gas furnace which was last turned on in 1984.