Since we got the chickens, I've never used light, honestly I had never thought to, the only light source comes from the lamp attached to the back of the house, and that's only for me, so I can see into the back yard. Plus since we have birds, if I want a good night's sleep, it's lights out for everyone
I will admit that at first I was a little nervous leaving everyone outside last night, got pretty cold last night, not below freezing, but because these guys are our 1st group of chickens, I don't want anything to happen to them, I have had all 9 in overnight, but I resisting doing that again