With the recent addition on the thermo-electric peltier unit, which appears to be rather underpowered for any serious refrigeration or air-conditioning, I would love to see the addition of a proper cyclical heat pump, including evaporator, compressor, and condenser. The compressor could use a power node and come in different sizes to fit cooling applications. Using a power node would allow for powering refrigeration units both using engines and electric motors for more versatility. I am aware this may be implemented using the soon-to-arrive modding feature (very exciting!), but I think it would be better suited as a part of the main game, and as a counter-piece to the rather weak cryo cooler.