Four mechanical engineering students have come out with a method to make ice in an environmental-friendly manner using solar power.Shying away from the conventional way of making ice using electricity, A. Ashwin, S. Sivagurunathan, S. Thejas and C. Srinath, students of Amrita Vishwa Vidyapeetham, have undertaken an experimental project to make ice using solar power. The final year students attempted the project in a small way with limited resources.
The project titled “Design and Fabrication of Solar-Powered Vapour Adsorption Ice Maker” involves a parabolic trough collector that attracts the sun’s rays and collects solar energy. The trough collector, which is the prime mover for operating the vapour adsorption system, produces hot water. There is a tank to collect the hot water and circulate the same.Water tank
The water is continuously circulated through the absorber tube on which the sun’s energy is concentrated. An absorber made of copper is placed inside the water tank. The absorber is filled with activated carbon and methanol pair.When the water gets heated up because of solar energy, the desorbed methanol vapours are condensed and collected in the evaporator. The water tank that contains the absorber and the evaporator are placed on either side of the parabolic trough.
The equipment is kept under direct sunlight for nearly four hours. The temperature is maintained for three to four hours. Once the temperature dips the hot water is replaced with water at ambient temperature. When the condensed water is drained out ice is produced in the water jacket surrounding the evaporator as methanol gets re-adsorbed by activated carbon.
“The system has a double use. It can be used to heat water up to 400 degrees centigrade and can also be used to make ice. Water up to capacity of 35 litres can be boiled. Since it was an experiment, we had to repeat many things, so the whole thing cost us Rs. 20,000.Otherwise, with correct specification the system will only cost around Rs. 10,000,” says Thejas.
The system is expected to be of use in rural areas where preservation of food and vaccine is a problem.