Practical Action Nepal has developed cold technology especially in the direction of rural areas. This technology is called Naya Cellar Storage. It was originally conceived by Dr. Gyan Shresthra of the Green Energy Mission and by Mr. Joshi.
This material is very simple to adapt to the needs of the user. The construction of this refrigerator is made from local materials. The results are significant for rural users who have low incomes or who are away from a sufficient source of electricity.
Shelf life of vegetables
|1 à 3 mois||3 à 4 mois||plus de 4 mois|
|Laitue , radis, roquette||Betterave (variétés hâtives), carotte(variétés hâtives), courgette, épinard, haricot, navet, pois, pomme de terre||Ail, fenouil, aubergine, fève, betterave (variétés tardives), maïs, blette, oignons, carotte (variétés tardives), panais, céleri, Poivron, chicorées, pomme de terre tardive,chou, potiron, concombre, courge tomate...|
Detailed Construction Instructions
To achieve this cold room without electricity, the following basic materials must be assembled:
- Bricks: 1200-1500
- Sand: 400-500 kg
- Polyethylene Hose: 6 meters
- Water tank/Bucket: 100 litres capacity
- Bamboo/Wood: 1.82 m in 2 pieces and 2.15 m in 2 pieces
- Straw: 2 Boots
Choose a space of 1.5 x 1.5 m2 (5 ‘ x 5 ‘) sheltered from the sun. The terrain will have to be slightly steep to allow excess water to evacuate and not to stagnate inside the chamber.
The dimensions of the construction can vary to suit the needs of the user. The cooler the volume is, the larger the size of the room will be.
Classically, a rectangular structure of baked bricks, without mortar, is constructed of 1.20. x 0.90 m on a height of about 1, 20meters.
Spread a layer of sand about 2.5 cm thick on the surface where the chamber is to be constructed, then place a layer of bricks on the sand.
The double-walled chamber is made of bricks. The gap between the inside wall and the outside wall of the chamber is about 12.5 cm. Fill the cavity between these two clean sand walls.
A flexible polyethylene pipe that you have pierced with a pin is placed on the sand inside the hollow. The hose is clogged at the end, the water flowing from a high reservoir flows through these holes and keeps the sand moist. Test the number of holes needed to keep the sand wet at all times. A straw roof supported by four wooden stakes is arranged over the cold room.
The air passing around the chamber is cooled by the action of evaporating water soaking the porous bricks, thus extending the shelf life of what is kept in the room. It is therefore imperative not to obstruct the air flow around the room. Bamboo bags and rods are used to cover the room, they are kept moist by watering them.
To prevent degradation of fruits and vegetables, they must be stored carefully in bamboo or plastic mesh trays/baskets. The trays/baskets must be raised in relation to the floor of the chamber. The flow of water in the sand must be regulated in response to changes in the outside temperature to allow the internal temperature of the chamber to remain constant.