Crafted by a potter named M Sivasamy, this clay pot was designed to help keep produce cool for days.
He made a cylindrical pot made out of clay with a tap on one side and an outlet to pour water on the other side. A smaller pot fits inside the bigger one where you can place your vegetables which is then covered with a lid. The technology is simple — the water in the pot remains cool keeping the vegetables fresh and cool. - BetterIndia
For places with no or limited electricity, this could help immensely. Especially considering terracotta(earthenware) clay is almost used worldwide.
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Close to a zeer pot in construction but with modifications, like the functional difference between a broom and a mop.
Those are the conditions a zeer pot is meant to work in, although this fridge’s indirect cooling and lid rather than the pure evaporation of a zeer pot makes his invention useful in all climates rather than only dry conditions.
As for not being a closed system, that is the point of this invention: to have a simply refilled, working refrigerator with zero energy.