Originally Posted by DoStep
If one freezes water jugs for the purpose of keeping coolers cold, would pouring water out of them on a regular basis make the ice last longer?
It would make the ice last longer.
The liquid water is a more effective medium to transfer heat. Air functions, in this case, as an insulator.
If you wanted to cool your warm beers faster, leave not only your liquid water in the ice jugs but also add water around the jugs and beer cans.
Two day or eight day trip.
Your ice management may vary.