Pot-in-Pot Refrigerator

Photo credit: Peter Rinker

Rethinking the refrigerator

Cycling refrigerant throughout a refrigeration system, the process which occurs in modern day refrigerators, isn’t the only way to keep food cool. Keeping food cool is important in order to reduce the rate of harmful bacteria growth and keep your food from going bad. While modern refrigerators may seem like one of the most common and useful methods of food preservation, the truth is that these types of refrigerators not only have a negative effect on the environment, but they are also not accessible to many people. Refrigerators that were made prior to 1995 may contain hazardous materials such as chlorofluorocarbons, greenhouse gases, and ozone depleting substances. New refrigeration appliances, although they have improved, still contain greenhouse gases called hydrofluorocarbons which have the ability to trap heat in the atmosphere and contribute to global warming. Additionally, refrigerators can consume copious amounts of electricity, which further harms the environment and your wallet, and is not accessible in many parts of the world.

The importance of refrigeration

Low-tech cooling units are another method of food preservation and refrigeration which are accessible to people around the world who do not have access to electricity. This is important, as lack of refrigeration is one of the main causes of food spoilage. Fresh produce has a limited shelf life without refrigeration. It can only last for a couple of days before becoming inedible. In certain African countries, such as Tanzania and Nigeria where the majority of people depend on agriculture as their livelihood, a large percentage of crops are lost due to the lack of refrigeration. This results in an inadequate amount of food at the production level, as well as on an individual level, as families deal with the same food-spoilage problems due to lack of refrigeration.

An award-winning invention

Lack of refrigerators in rural northern Nigeria was an issue that Mohammed Bah Abba, a local teacher, developed a solution for in the 1990s. His invention, the Pot-in-Pot Preservation Cooling system allows perishable food to be preserved for weeks instead of a couple days. This refrigeration system consists of a small clay pot which is placed inside a larger one. Perishable food is stored within the smaller pot. The space between the two pots is filled with moist sand. A wet cloth covers the tops of both pots. As the water in the sand evaporates through the surface of the larger pot, it removes heat away from the smaller pot, therefore keeping the food cool. This low-tech refrigerator is quite simple to make and use, yet it has made a large impact. Abba received the Rolex Award for Enterprise in 2001 and used the awarded $75,000 to make his invention available throughout Nigeria. The Pot-in-Pot Preservation Cooling System not only allows the preservation of food, but reduces food-related illnesses, increases food profits, improves diet variety, and creates rural employment opportunities.

Cooling Technology Helping Africans

Rolex Awards – Mohammed Bah Abba