It's like pre-loading your refrigerator/freezer with a sack of ice. If your power goes out long enough for your food to spoil, what will you do? Well, maybe you'll go buy some sacks of ice to throw in there until the power turns back on.
Ok, if you have the space to spare, why wait for the failure to go fetch the emergency ice? Just fill the empty space with ballast water and you're ahead of the problem.
Once the thermal mass is at the desired temperature, it will help bring newly introduced items to the desired temperature faster, not slower.
The only time it slows down the cooling is when first introduced @ a warmer temp, or when there's been a failure for long enough to let everything warm up. But note that in the failure scenarios, the thermal mass helps keep the space cool for longer than had it not been there. Just remove the warmed ballast when the failure is over to let the perishables re-cool first, then reintroduce the ballast when appropriate ... perhaps even pre-cooling it elsewhere first.
Practically all of your food has a thaw point that’s below the thaw point of ice. The energy absorbed in the phase transition of ice to water massively eclipses the energy to heat up the same amount of water by one degree. In effect, all your food will protect your newly acquired ice from melting.
You want something that has a thaw point way below your foods thaw point - add salt t your ice.
I had never thought about this but you're right. Big frozen water/soda bottles of ice still increase the overall thermal mass and will almost certainly slow full thawing. Otherwise, ice blocks in a cooler wouldn't work.
But you're really better off adding salt to those bottles so they absorb energy when melting below the freezing point of pure water (and frozen food).
While that's true, since the current topic of this conversation is about emergency preparedness, I think having potable water (in ice form) would be much preferable to salted water.
It’s substantially more efficient to store a pack of bottled water or two on top of your fridge - and keep your food at the same time. Water keeps well even if not frozen.
If you want to keep tap water, you can buy silver ion additives at any camping/outdoor store. If you’re really planning for preparedness, buy a ceramic water micro filter and additives. That can make nearly all water usable.
Ok, if you have the space to spare, why wait for the failure to go fetch the emergency ice? Just fill the empty space with ballast water and you're ahead of the problem.
Once the thermal mass is at the desired temperature, it will help bring newly introduced items to the desired temperature faster, not slower.
The only time it slows down the cooling is when first introduced @ a warmer temp, or when there's been a failure for long enough to let everything warm up. But note that in the failure scenarios, the thermal mass helps keep the space cool for longer than had it not been there. Just remove the warmed ballast when the failure is over to let the perishables re-cool first, then reintroduce the ballast when appropriate ... perhaps even pre-cooling it elsewhere first.