I'm guessing it'll be about $600 a month. Give or take. Lots of insulation, and off peak electric boiler to heat the floor. I'm pulling that number completely out of my butt though. The current shop is 2500 sq/ft and costs me about $150 a month to heat using the same system. So about $.06 per sq/ft per month. The new building will have a 16' sidewall instead of 12', so that'll lose more heat. I've got room to do geothermal, and I'm trying to figure out if I can afford to spray foam the whole works instead of just batted insulation.

Luckily I only have to heat six or seven months out of the year....

If you told me I could have a million dollars at 8am, but only if I could spend it before lunch, I'd be done by 9:30