Heat has been on a few times[u][/u]. The bills have been, in my opinion,have been real tolerable. I am on the budget, and since the new budget cycle came in August, they have been cut by more than $60.00 for the new billing. The whole house has been finished now, and as for heat, I have it set at 64, and the house holds the temp. quite well. I think when the real cold stuff gets here, if I raise it up to 65 or 66, it will hold its own as well. I am quite happy with the whole thing so far.