Gearing up for this here too. We have our first few nights below 30 this week. We raise 4 girls in a suburban backyard in a tractor. Due to zoning issues, I am not allowed to run power to my tractor/coop. No issues for the girls, but the frozen water is a concern. We use a DIY nipple waterer. I looked at two options: first, ignore zoning and run an extension cord and use a tape heater on the nipple waterer. I could do this with no problem since the only neighbor that could see it is one I give eggs to and she likes the chickens. Other option was to move the girls into a temporary coop in the shed, where I have power. I opted for the shed since it gives me better light control and hopefully solves the frozen water issue. I'll pick up the heated waterer that oaxa mentioned if an issue develops.