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The big problem is that 90% of modern fridges are just not suitable for the changes.... with the heat exchanger in the side walls.
Your old style (rather small) fridge, was suitable, so that's good..
I wonder how long it will be befor we see purposefully designed devices, that have the thicker walls..
Maybe we will never see them because the number of folk prepared to sacrifice useable cold-space for efficiency, is likely small.
With Governments forcing the issue on devices like Water-Heaters, and water-efficient-washing-machines, it's a wonder that they don't pass laws about the thermal efficiency of fridge/freezers, but, we know that they are not really serious, with encouragement for Solar-Power installations and then removal of the encouragement, because they find that it costs money.
WHY - should we even have to think about adding insulation..
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