McDave wrote:Why doesn't the cold just come out the top? That's not what cold does, cold falls, heat rises.
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a bucket that holds the cold and keeps it from falling out and spilling all over the floor.
"Cold" is not a thing, just an attribute, an absence of energy.
Two points. Opening from the top, the turbulence does pull lots of cold air out, warm air mixes in.
Second, air has **so little thermal mass** it takes very little energy and time for temps to recover even if all the air is swapped out.
As long as the space is Full, of things **with** thermal mass.
Which is important to efficiency regardless.
If you take out a gallon of heavy, and replace with a gallon of heavy, say water, yes the fridge will work for hours to recover.
But over time that process is more efficient than leaving that gallon to be replaced by air alone.
Of course for a weekend off grid, probably a wash,
but can get by without a fridge easy in that use case,
my assumptions are long term living off grid.
And the main point is that the overall energy consumption **difference** between chest and front opening is insignificant, especially compared to lots of other factors under our control.
Adding a 1/4" extra insulation was just one of many examples, none of which are that significant, but all more so than that choice.
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As to the rest, no idea what you mean. In normal operations of course insulation, door seals etc need to be optimal.
And with grid / shore power, energy efficiency is of lower concern, by factors of magnitude.