I found this page when looking for a product that is almost in the same category. A commercial unit is out there called Ice Bear, but it’s not for a house. I was wondering if a central AC unit’s coolant line could be looped and coiled through a block of ice inside a 15cuft freezer before reaching the compressor. Less work for the compressor and the ice can be made during off peak hrs as thermal storage. The 120v freezer can be on a timer to come in evening and placed below ground level where it’s cooler instead on the hot air as is the conventional condensing coil.
UH yeah uh… 
Check this out Homemade Minifridge Air Conditioner - YouTube
I’m thinking run a copper pipe through the plastic part of the magnetic seal on the freezer. Coil it on a mini desk fan. Run it back into the freezer. Hook it up to a mini sub pump for aquariums or hydroponics. Drop the pump in a reservoir like bottle or Tupperware filled with an low freezing temp liquid like antifreeze, everclear, moonshine, over proof rum, 151, 99bannas/apples/etc… maybe vodka, but I’ve had a mini-fridge that froze 80proof solid. Probably be ok with everything sealed if the size of your fridge to fan to camper is not too much for your fridge to handle. Of course as originally stated in the initial question you must vent the heat from the fridge. I’ve seen them with blowers or you could put the condenser coil outside your camper.
Additionally If you dip the copper coil down off the fan to drip you will have an atmospheric water condenser. A source of clean distilled water. Very Kool in a camper.