Alternative for Electric Refrigerator - Claypot Refrigerator
Source: https://www.permaculturenews.org/2017/07/26/alternative-refrigeration-techniques-food-storage/
Author: Tobias Roberts
A clay pot refrigerator, also known as a pot-in-pot refrigerator is a simple, powerless device that uses the principle of evaporative cooling to keep foodstuffs fresh and cool even in the hottest temperatures. This simple “appropriate technology” was developed by international development organizations searching for ways to help rural villagers around the world without access to electricity find ways to preserve their food. A clay pot refrigerator utilizes a porous outer earthenware pot, lined with wet sand or other substrates, and an inner pot (which can be glazed to prevent penetration by the liquid) where food is placed. The evaporation of the outer liquid (contained in the sand or other substrates) draws heat from the inner pot. You can make a clay pot refrigerator in many sizes, from a small pot that just holds a gallon of milk to a full-sized refrigerator. This simple technology requires only a flow of relatively dry air and a source of water to keep your foods preserved.