Hi Avery, where are you located?
IMHO chickens don't need heat except in the most extreme climates. During the polar vortex last year I kept the window open in my hen house. They came through with no frostbite.
Using solar to keep the water unfrozen would be very helpful though!
looking forward to seeing replies.
Hello Avery. Welcome to BYC! As @Justso mentioned, you don't need to heat the coop unless you are in an area that gets extremely cold temperatures. I have a solar powered light in my coop but that's all. It got pretty cold here last winter during the polar vortex and my chickens were fine.