Another solar novelty
A new solar dryer developed by a team of scientists headed by K K V Nair from the Bhabha Atomic Research Centre (BARC), Bombay, has made it easier to dry agricultural products.
Unlike the conventional solar dryer, the new apparatus can be folded and efficiently dries fruits, wafers, green pepper, spices, papad and other food products. It can be made with available indigenous materials like aluminium angles, sheets, rivets, hinges, brass nuts, thermocole sheets and heat-proof black paint.
The heat is first absorbed by the black aluminium mat surface of the dryer. This, in its turn, heats up the still air inside the dryer. The hot air dries the agricultural products spread out in trays by evaporating the trapped moisture. A vent at the top provides the exit point for the moist air.