The most obvious solution is to chill the house that has the hab. But I don't have AC. I have a pretty strong window AC that I could run a pipe from to the hab. No radiators needed, the air could blow in through a 1 1/4 inch pipe. But I can't afford to run that unit all day long, every day.
Unfortunately, I'm now living in an area that is about ten degrees hotter than where I used to live. So I've never run into this problem before.
ANY heat input causes bad temps. Even fluorescents do that in this case. I've moved the ballasts out of the cage, and hung them from a wall above the hab. But even the tubes themselves get too warm. To keep the temp at 80 to 85, I can't have any lights at all inside the hab during the warm months. My only idea for white light is to use individual led's that are not inside a fixture. With LED's, the resistor heats up, so for this problem the resistor has to be away from the cage. The wiring is very simple.
Right now the creature lives 24-7 in an unlit hab. I must resume UVB, but only for 1/2 hour at a time, maybe once every two hours. Luckily he does use the UVB on his own.
The best answer for me is probably a chiller of some sort, that is run by the thermostat. I know how to build the simple, old-fashioned chillers, that use evaporating cascades of water droplets. It would be located outside, with insulated tubes between the hab and the chiller. I will need to find some kind of heat exchanger. Maybe the cooling radiators on the inside of cars. It would have to be inside the hab, with a small fan blowing through it.
Over and out,