Cooling down your car interior by running the air conditioning can be an exorbitant use of energy, especially in very hot countries. So what if there were a way to remove all that heat without using fuel or electricity?

As it happens, plants do this naturally. Tri-Gen, a plucky team of engineers studying at the University of Cambridge, saw an opportunity to use a similar process to cool down a car. They entered their innovative idea into Shell’s global Ideas360 student competition and it’s beaten almost 1,000 other ideas to win them a place in the final.

On July 1, 2016, the Tri-Gen team will be whisked to the Shell Ideas360 grand finale at the Queen Elizabeth Olympic Park in London. The final is a part of Shell’s massive festival of energy ideas and innovation, Make the Future London.

Here the Cambridge team will compete against four other teams from the University of Illinois, Indian Institute of Technology, Singapore Management University and Nanyang Technological University.  The winning team gets to go on a National Geographic Adventure tour of their choice and to take the prestigious Shell Ideas360 trophy back to their university.

Team TriGen from University of Cambridge, finalists in the 2016 Shell Ideas360 competition.
Team TriGen from University of Cambridge, finalists in the 2016 Shell Ideas360 competition.

Introducing Team Tri-gen

Team Tri-Gen comprises civil, structural and environmental engineering student ZiQing Liew, engineering student Vivian Kah Ong Wong, and chemical engineering student Ze Kai Tan, who met through the close-knit Malaysian Society at university. Their idea is the Transpirational Car Rooftop. It uses the phenomenon of transpiration to efficiently divert heat away from the car, just like a leaf. This means drivers in hot climates can start a journey without first turning on the vehicle’s air conditioning.

“We’re all from Malaysia, which is very hot,” says ZiQing. “We wanted to find passive ways to make ourselves more comfortable in our day-to-day. It struck us that in the heat we use our car’s air conditioning a lot. We asked ourselves, ‘How can we make a car more fuel efficient in that sense?’

“Vivian is passionate about bioengineering,” he continues. “She has been studying how plant cells cool themselves passively, without using extensive energy. This inspired the Transpirational Car Rooftop.”

What is transpiration?

Transpiration is the process by which a plant moves water and minerals upwards through itself, against gravity. As water evaporates from the surface of the plant’s leaves, water further down is naturally drawn upwards by a capillary action, to replace what’s lost. This produces a flow of dissolved minerals, distributed to the plant’s every extremity. At higher temperatures this process accelerates; as more water evaporates, more heat is carried away from the plant’s leaves, cooling the surface.

Why Shell Ideas360?

The team made the decision to enter the competition simply because they were looking for new engineering challenges to get their teeth into.

Shell has been involved with the University of Cambridge’s Department of Engineering for some time, so the team were aware of Ideas360.  Indeed, friends of theirs had entered the competition in previous years. “We were just looking for a new challenge,” says ZiQing. “Shell Ideas360 presented a perfect opportunity.”