So I live in MN and was going back and forth about heating the coop. I really was ready not to but I got cold feet when I looked at the 10 day forecast. My lovely DH put up my sweeter heater on Friday morning right before the winter storm from he**. The heater is great. It only raises the coop temperature by about 10 degrees. But considering it was -13 the other night, zero seemed alright to me. Pancake likes to sleep with her face right next to it. It is very cute. So I give it two thumbs up!