In 2001, Nigerian Mohammed Bah Abba won the 2001 Rolex Awards for Enterprise with his invention of a simple cooling system to preserve food in rural areas with no electricity. His solution was a Pot-in-Pot refrigerator, which relies on the concept of evaporative cooling. The system works by putting a smaller clay pot inside a larger one, separating the two by constantly moist sand. Evaporation causes a cooling effect in the inner pot. Eggplants are reported to stay fresh for 27 days, nine times their usual expiration date. Tomatoes and peppers can last for up to 21 days (I can’t even get that to happen in my own refrigerator!) More information.
