The main aim of the project is to design an electric less refrigeration system using copper coil and air tube along with the cooling device which works without any electricity. Solar energy is treated as non renewable source of energy.   "We thought it would be good to decrease the amount of food waste in the world, and we came up with this design because it's easy to build and the materials are relatively cheap," Dubbed the Wind Chill Food Preservation Unit, the device connects an air tube to an evaporation chamber, which connects to a sealed refrigeration chamber that looks a lot like an esky, the contents of which are cooled through the process of evaporative cooling. It works by passively drawing in warm ambient air through the funnel, which is fed into a pipe that’s been buried underground. This already starts to cool down the air before it's fed into coiled cooper pipe that’s been immersed in water in the evaporation chamber. The evaporation process is helped along by a small, solar-powered DC Fan. The water evaporating around pipe chills the air inside and this is then fed back underground before entering the refrigeration chamber. "Anywhere from a quarter to half of the world's food goes to waste every year, and in rural populations - about 70 percent of the people in rural Africa don't have access to electricity. "So this at the moment uses a tiny bit of electricity from a solar panel, but the end design is to use zero electricity. So this could really help people in those areas."          

The main building blocks of the project are:  

1. Air tube
2. Copper coil
3. Chamber
4. Solar panel.
5. ON/ OFF switch.
6. Charging circuit
7. Battery
8. Coolant fans
9. Display.

       

Block Diagram:      

video: