February 14, 2011
Bill Gates might want to take notice: students in UT's Aerospace Engineering program have designed a low-cost, solar-powered refrigerator that could help in delivering vaccines to hot and arid parts of the world — with no need for electricity. The Student Engineering Council (SEC) already has taken notice: the four-person team, led by senior Travis Sanders, won the 2010 SEC Alternative Energy Challenge (AEC) Award for their evaporative refrigerator.
The AEC competition encourages students to create innovative ideas for generating power through renewable and sustainable methods. Sanders' team, which included junior Kaitlin Decker, senior Eric Ferguson and senior Grant Rossman, received $1000 as well as a bonus $500 to their organization, the UT Chapter of the American Institute of Aeronautics and Astronautics (AIAA).
"The original intent for the refrigerator was to store vaccines in impoverished parts of the world," Ferguson said. "Through the process of transport, they're losing a lot of vaccines because they're getting too hot, and when vaccines heat up, they spoil."
The refrigerator, which took only two weeks to build and cost only $260, uses an evaporative process to cool its contents. The compact, airtight, insulated wooden box has multiple round holes cut into the top of it, and an aluminum water bottle plugs into each one. Towel sleeves, saturated with water, are wrapped around the bottles, and as the water evaporates from the towel, it cools the water bottle as well as the air inside the bottle. The cool air inside the bottle sinks into the box as the warmer air already in the box rises.
Because many areas where the refrigerator might be used may lack wind, which would speed up the process of evaporation, the team added a hand-cranked fan that can blow air over the system. Wind could also blow over it as the refrigerator is transported on the back of a bicycle, a truck, an animal or any other form of local transport.
"We came up with the idea for the fridge first and then thought about what would be a good application for it," Sanders said. He said one judged recommended using it for camping and backpacking. Sanders said it can be used for any kind of perishable and can be made for less money by using socks instead of towels or building these refrigerators in bulk.
"Our goal was to make it very low cost," Ferguson said. "We wanted it to be affordable for poor areas."
