Pot-in-pot refrigerator

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The pot-in-pot system is an appropriate technology. Appropriate Technology is a technology that is practical. It must be easy to construct. They also need to be constructed from materials that are available and made by local people.

Pot-in-pot was developed in Africa. It was created for people to store food for longer periods of time. There are two pots, a small pot inside of a larger pot. Between the two pots there is sand, and when water is pored on the sand it makes the inner pot colder via evaporation (evaporative cooling). This is used like a refrigerator to keep things cold.