My coop is small and not insulated. The chickens basically sleep next to a plywood (where windows are closed, but surely leak air) while their heads are only inches below the vent of the roof. Wind protection is still very good, so I don't think I need heat all winter. I'm just thinking that on the worst days a little supplemental heat could be useful. I have a ceramic bulb that I use in my brooder, but there really isn't any room to hang anything in my coop--especially where the chickens wouldn't bump into it. So a heat lamp is out. However, I have some small ceramic desk heaters that would fit perfectly in an empty nesting box. It seems way safer than a dangling bulb, and since heat rises, it should be more effective. Plus, it has a thermostat that can be turned down quite low. My main concern is how much energy these things might use. Has anyone tried one?