Looks like 9.25¢/kWh would be break even at today's price & hashrate. Home miners can't really expect a profit that way, but if you're using the heat to offset the cost of running your furnace in the winter, then the math swings much harder in your favor.

This past winter, even running old S9s were more or less break even since I didn't have to run my furnace at all which saved me something like $150-200 a month.