Engineering Science
Students invent pedal-powered vaccine cooler to save lives in developing countries
Immunization saves millions of lives each year, but getting vaccines to rural villages in the world’s poorest countries is difficult.
Not only can road networks and electricity access be unreliable, high temperatures can render vaccines ineffective—a particular challenge in desert-like climates like Sub-Saharan Africa, Asia and elsewhere.
To tackle this issue, a team of first-year engineering science students from Simon Fraser University has created a first-of-its-kind bike-powered electric cooler bag.
Keeping vaccines cool in extreme climates
The clever mechanical system uses electricity produced by pedal power to refrigerate a cooler bag for up to six hours, even when the bike is not in action.
The team, who created the project in just three months in ENSC 100W/105W: Science, Technology and Society, “wanted to work on an issue that meant something to us,” says team member Anysa Manhas.
“We were researching the world’s biggest problems needing solutions when we came across the issue of vaccine access in developing countries—it got us thinking about how much we take for granted in Canada,” says Manhas.
Vaccination coverage remains lowest in rural areas of developing countries that lack the infrastructure and electricity to access and correctly store temperature-sensitive vaccines.
A breakdown in the refrigerated supply chain (called the ‘cold chain’) at any point will cause the vaccines to spoil and become ineffective, causing unnecessary death and suffering. In fact, it is estimated that inventions to store and transport vaccines could help prevent nearly one million deaths each year.
Using technology to solve world challenges
With this in mind, the student team of eight set out to transform a regular mountain bike into the lifesaving ‘Cool Bike,’ bringing effective vaccines to remote areas that need them most.
The system, designed and built by the team with little prior experience, works like this: a custom chain attached to the front sprocket of the bike drives a freewheel gear, which then turns a generator that charges a lithium ion battery. The battery then powers a Peltier unit to generate thermoelectric cooling, thus extending the vaccine cold chain without the need for external power.
“At the moment, children from smaller villages often have to walk for miles in extreme heat to get vaccinated,” says team member Richard Webb. “With our system, a designated person from a village could cycle the Cool Bike to a larger town and collect sufficient vaccines to take back. The battery stores power from cycling on the way there, which can be used to power the cooler with the vaccines on the way back.”
“Or a volunteer could cycle to an isolated village to bring vaccines to people that can’t be reached by a truck or van,” adds Manhas.
A practical solution to create real impact
To work in the real world, the team’s invention needed to be more than an efficient cooler—it had to be a working bicycle with structural integrity and high-usability.
“We disconnected the front derailer to stop the bike shifting gear–this keeps it in the strongest gear to generate the most power, but the back gear still works normally,” says Webb, whose bike was used for the project.
The chain, which the team cut to size and mounted, also had to be precisely lined up parallel to the seat to stop it detaching—a process that took several hours of trial and error.
The team’s perseverance did not go unnoticed by professor John Jones, who teaches the course. “They did a very good job of implementing the mechanical chain drive, which I'd expected they would find difficult,” says Jones, who awarded the team the highest grade in the class.
The team, who recently started their second term at SFU, has no immediate plans to commercialize the invention, but they haven’t ruled out taking it forward in the future. In fact, they already have ideas for improving the next prototype, including a lighter battery, and a shockproof system to protect the vaccines in transit.
“I’m proud of us and what we achieved in a short space of time,” says Webb. “This is something that could really help people. Who knows, someday you could even buy a village a Cool Bike.”