Well i have free power so... depends i guess.
Hope your not stealing it....Are you getting solar power? Or you at a college dorm that includes utilities? Or at a company using mining as a way to test hardware?
I'm also interested to know too, I find it so hard to reduce my electricity bills.
Just use your electricity during off peak hours and partial peak hours, that should help. Look at your electric bill for that info. Nothing is free in life.