BEFORErefrigerators became the norm of the day, earthen pots were used to store cool drinking water. The water in the pot reaches the outer surface through the pores in the earthen pots which on evaporation, humidifies, cooling the air around it. This in turn cools the water in the pot.
Based on this principle, several low cost refrigerator models are available, which can be used for short-term preservation of household products (Changing Villages, Vol 14, No 2). Requiring a capital investment of Rs 50 only, these refrigerators are made from locally available material like clay, bamboo, sand, cloth, moistened bricks and thickropes. Negligible maintenance and nil operational costs are its otherfeatures. The refrigerator allows householdproducts like milk tostay put for about 20hours, curds for fivedays, eggs for 20 daysand vegetables for a week.
Five models of these evaporativecoolers, portable and easy to assemble,are currently available in certain parts ofBihar and West Bengal. Among them isthe pot in a pot system which makes the'Earthefi Cooling Pot'refrigerator. Water ispoured'Amto the outerchamber and the smaller pot is used to store the food.
These rural refrigerators record temperatures four to fivedegrees less than theroom temperature and 23-25 per cent higherrelative humidity.
Apart from being ejonomicallyviable and environment- friendly,these refrigerators can help improvethe nutritional status of the ruralpopulace.