I have a set of lights in my coop not for eggs but I want to spend time with my chickens I got them first and formost as pets and have built a bond with them and when I work I dont get off till 5:30pm and during the winter months its dark when I get home and before work I dont have time to spend with them plus my chickens like to hang out till way after dark forging and eating with the porch lights. I dont see no harm in it and my birds seem to be very happy and tonight they put them selfs away at 7:30pm the lights dont go off till 9. the light I use I got from lows in there garden section there basicaly 12 christmas lights with bamboo around them its very soft lighting.