Call me crazy, but solar was actually a LOT cheaper than running electricity to the coop from the house. We were literally less than 50 feet from an electrical source, and thought it wouldn't be a problem to run a line out there. However, after receiving two estimates, we were unwilling to pay that much. So I had DH set up a solar panel outside, and created a cabinet inside coop to house battery, inverter, etc. Works beautifully! And there is more than enough power for a light and a fan for summer or heater to keep water from freezing in winter!