Ice in the Desert: A Fridge without Electricity

According to the Bible, you can make ice in the desert.

The process is not an act of faith but actually one of physics . It is the result of heat transfer that takes place during evaporation.

if one dug a shallow hole, lined the cavity with straw and placed a ceramic pan with a thin layer of water into the straw-lined nest, then there would be minimum conduction, little or no convection, and radiant heat transfer to outer space would control. Since outer space has an equivalent temperature of minus 400 degrees F, and radiation is governed by the difference between the absolute temperatures to the fourth power, you can make ice in the desert. – Jerry Roach

This principial has now been used to invent a fridge which doesn’t use electricity.

Here’s how it works. You take a smaller pot and put it inside a larger pot. Fill the space in between them with wet sand, and cover the top with a wet cloth. When the water evaporates, it pulls the heat out with it, making the inside cold. It’s a natural, cheap, easy-to-make refrigerator.

The inventor, Mohammed Bah Abba, comes from northern Nigeria, where over 90% of the villages have no electricity.

The invention won him a $10,000 Rolex award for Enterprise.