All of the individuals that I know have always used the refrigerator as a modern given convenience, never thinking that it in fact would be a luxury to a third of the world's population. That's correct, a third of the world's population lives without electricity and so struggle with the basic need of preserving food due to heat and flies.   

However, Mohammed Bah Abba, a Nigerian teacher is trying to change all that with his invention of a pot-in-pot refrigerator - a refrigerator that does not require electricity.  

Mohammed used knowledge from his family of pot makers and the laws of thermodynamics to create the Zeer (Arabic for pot-in-pot refrigerator). This is how the device works: "You take two earthen pots, both being the same shape but different sizes, and put one within the other. Then, fill the space between the two pots with sand before pouring water into the same cavity to make the sand wet. Then, place food items into the inner pot, and cover with a lid or damp cloth. You only need to ensure the pot-in-pot refrigerator is kept in a dry, well-ventilated space; the laws of thermodynamics does the rest. As the moisture in the sand evaporates, it draws heat away from the inner pot, cooling its contents. The only maintenance required is the addition of more water, around twice a day".  

The Zeer is a simple solution to a problem affecting so many - it not only allows people to store food for days that would wilt in hours but also helps small farmers from losing stock and improving their economics. As well, the health of so many has improved due to better preservation of vitamins and the reduction of dysentery due to the separation of food and flies. 

Read the full story at Celsias.com

---