It was already answered, but conventional AC systems have resistive heating elements which have a a max efficiency of 100 percent. Heat pumps run an AC in reve

It was already answered, but conventional AC systems have resistive heating elements which have a a max efficiency of 100 percent. Heat pumps run an AC in reverse which can give a COP of 3-4. (300 to 400 percent efficiency) or if actually burning fuel for heat. Could just remove the need for direct fuel burning altogether. Highly dependent on area, and associated costs. I recommend that you run the numbers for your area