I posted something about this way back, but will repeat it. We put a layer of bottled water in the bottom of the freezer at the beginning of each season and let it freeze solid. The refer will stay cold for at least a full day without being turned on that way. We also can pull a bottle or two out if we're going on an outing and need something to cool our 'travel' cooler (stick a couple new ones in when we do this). Since not much can fit there anyway, this works very well for us.
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