I don't have a fan on mine. I'd have to run an extension cord outside because they're in a tractor. I've been worried about it raining on the fan so I haven't done it yet.
I've also been thinking of letting them free range so they can get into the woods where it's cooler.
It's been mid to upper 90's and so humid here in MD lately. My poor birds are suffering. I lost a laying hen the other day, and I lost a cornish X yesterday. Two others were at death's door, but I put them in a bucket of cold water to cool them down. Their skin was SO hot to the touch...