The Pot-In-Pot Cooler is an extremely simple device made from two pots, sand, and water. Used in rural areas and developing countries, where electricity is scarce and precious, the Pot-In-Pot Cooler uses the evaporative power of water to draw heat energy away from the contents.
In rural Nigeria, many farmers lack transportation, water, and electricity, but one of their biggest problems is the inability to preserve their crops. With the Pot-in-Pot, tomatoes last for twenty-one days, rather than two or three days without this technology.
I have often noticed in developing countries around the world some of the simplest designs can reap huge benefits. In such cases need is the mother of invention where resources, materials, and energy are limited.
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The Pot-In-Pot (also known as the Zeer) was invented by Mohammad Bah Abba in 1995 for which he later won the Rolex Leureate Award.
One major factor critical to the function of a Pot-In-Pot Cooler is relatively dry conditions, so that evaporation will occur. This device would not see much success in a humid and tropical location but can offer great advantage to those is warm arid climates such as Cameroon, Chad, Niger, Eritrea, Ethiopia, Burkina Faso where it currently sees great use.
sources: Design for the Other 90%, SEED
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The thing I like best about this design is that it is essentially open source. Sure, you can have an Official Pot-In-Pot Cooler (TM) but the general principle can be spread throughout all those countries where it will help, and they can easily construct their own with existing pots, sand, and water.
Doubly excellent!
Nice read.