Refrigeration in the desert without electricity?
This one's an oldie but a goodie. Back in 2001, Mohammed Bah Abba of Nigeria won a Rolex award of $100,000 for his pot-in-pot electricity-free refrigerator design. It consists of a smaller clay pot inside a larger clay pot. The gap between the pots is filled with wet sand. As the water in the sand evaporates, the inner pot cools. Food that used to spoil in a few days now stays fresh for weeks.
It is said that this design will keep food from 15 to 20 degrees Celcius cooler in an arid desert climate. It doesn't work quite so well in a humid climate, but for the application here, in Nigeria, it's perfect. It's this type of innovation and back-to-our-roots thinking that many even in the western world are turning to lately. Check out the related link below for the complete story behind Mr. Abba's design and how it changed his life.
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