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solar powered cooler Answered

Using these ideas as a starting point:

"Another variant uses air, water, and a salt solution. Warm air is passed through a sprayed solution of salt water. The spray absorbs humidity from the air. The air is then passed through an evaporative cooler. Humidity is removed from the cooled air with another spray of salt solution. The salt solution is regenerated by heating it under low pressure, causing water to evaporate. The water evaporated from the salt solution is recondensed, and rerouted back to the evaporative cooler."

Directions on how to make an icy ball. URL works occasionally.


Is a non-flammable, non-toxic, and low pressure version possible?


I am obsessed with this! is it more important to have a no-energy fridge or no electricity ice maker?

"Free" fridges are already in use on continental Africa (I can't remember which bit).

Two clay pots are stacked together, one inside the other. The pots are porous, and the gap between is packed with sand.

Objects to be kept cool are placed in the inner pot, and the sand is thoroughly wetted (river water is fine).

During the day, water evaporates through the outer pot, carrying off heat energy and cooling the inner pot. I don't know how cold it gets, but it's enough to stop vaccines etc going off.