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How can you make a fridge more efficient? Uses of solar, heat exchangers, etc. Any ideas? Answered

I was thinking of a heat exchanger, on one end a constant stream of cold well water, on the other end, the fridge coils. Or maybe use solar to cool it with peltier effect device? To keep it from coming on too often. Throw out any ideas, just though of this but have not seen it around, probably for a reason. It would be nice to use this idea at a cottage or camp eventually with little to no power, but at a cost worth building. The point would be to save money over the long run, so like a full blown solar would work, but it would cost a lot. Thanks again


Insulate the box more. There is only 1" or so of PU insulation. If you splashed out on vacuum insulated panels, a 1" panel has the insulation value of 10" of PU. You can't (currently) beat a gas-compressor fridge for efficiency. Steve

if you keep the condensor coils cooler they will be more efficient you could also turn down the cold (make the fridge a little warmer)

Lemonie's answer about the gas-powered fridge reminded me of the one we used to have. I am not sure how it did it but all the gas did was run a small pilot light. This seemed to be enough to circulate the coolant and achieve some serious cooling - it even had a freezer compartment. So it seems to me that if you could focus sunlight onto the same spot that the pilot light was heating then you could 'run' it without the gas (at least during the day). Otherwise your idea of using ground-sourced cold water to assist the cooling grille on the back of the fridge should only help it work. Another way to improve the efficiency is to open the door less often. maybe install a 'curtain' of vertical strips of plastic that you reach between to grab the butter will help prevent the cold air from escaping whenever you open the door. And always allow hot food to fully cool down before putting it into the fridge.

You want an alternative power source, or you rebuild the fridge.
You can get gas-powered fridges (e.g. for caravans / RVs) so you might be able to replace the gas-heater with a solar device?
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