This video shows the science behind the pot-in-pot refrigerator, aka the Zeer pot. Pot-in-pot refrigeration is ancient technology that has been revived with a lot of success in Saharan Africa and rolled out to other developing regions. In those countries small farmers use the pots to store produce for market.
Here in North America, we could use it as a picnic/drinks cooler, to free up fridge space, to save on electricity, during an emergency or if we live off-grid and electrical refrigeration isn’t an option.
This is cheap, pretty easy-to-apply technology and gives you a cooler without the ice. My wish would be for someone to produce interlocking unglazed ceramic cubes or low rectangles so that this solution would be easier to fit into a kitchen or pantry. I know from what I’ve read that the pots have to be unglazed for the device to work – since it is cooling through evaporation through the porous pottery.
I am curious about what affects how quickly the pot cools (the presenter seemed to suggest that the temperature around the Zeer is a factor) and how long the effect lasts.