Our cooler room is nothing fancy, but it has about 3-4 inches of spray foam and a dirt floor and is 10'x10' with an 18,000 btu AC unit wired for 220 v. I try to keep it in the 50s temp wise with the Coolbot, which is about all I can get the AC to do, and I don't want to shock the calves when they have to go to a show in 85-95 degree weather all day. I figure it costs maybe $40-50 a month extra on the electric bill, but hard to tell since we are pumping the well quite a bit more in the summer to rinse cattle, water yard, etc., and run blowers and fans, all of which is the same time we are using the cooler.