Our house is 1350sf and there is a single wood burning fireplace in the living room, which is situated in the middle of the house and has cathedral ceilings (15ft high). My husband thinks it might be cheaper to use the fireplace through the winter instead of the heater. I think since we don't have a good place to get cheap wood it'd be cheaper to just use the regular electric heat.
Other things to consider:
The house is very energy efficient, with 2 feet of insulation in the attic and under the floor, and has double paned windows.
We are on an equal payment plan with the electric company and pay $138 a month. When we didn't, the highest bill we had during the winter was $195.
That shit is messy and we have idiot cats
We live in NC so it doesn't usually get colder than 20F here