A Cold Solution

Transporting a vaccine in the developing world is a precarious proposition. In many places electricity is nonexistent or unreliable. Vaccines, often chilled in ice to a precise temperature, must be raced to distant villages before the ice melts. In some areas the vaccine spoilage rate reaches 50 percent.

When Rogers Feng, a senior mechanical engineering student, heard about this issue, he went to work on a portable, human-powered solution. With help from several McCormick School of Engineering and Applied Science faculty members and the Segal Design Institute, Feng created a human-powered refrigeration system for vaccine field distribution. With five minutes of cranking, the device stays powered for 15 minutes. The cranking powers a small DC generator that charges a nine-volt rechargeable lithium-ion battery, which powers the thermoelectric modules to carry out the cooling process.

Feng’s design has several advantages. It includes a safety feature that protects against sudden temperature drops that can ruin vaccines; it contains no toxic refrigerant fluids, which could leak and harm the environment; and it is relatively inexpensive to produce, about $50 each.

In September Feng won the U.S. James Dyson Award and advanced to the international Dyson competition. Feng has started to research foundations in the search for potential backers for his refrigeration design.

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