A model car on the go for 10 hours.  An MP3 that plays for 20 hours.  Both are driven by a few drops of alcohol fuel.  Both point the way to an exciting new power source for the future, thanks to the breakthrough discoveries of Prof Tianshou Zhao, Chair Professor in the Department of Mechanical and Aerospace Engineering at HKUST, and his research team.

As communities around the world increasingly emphasize the importance of green and sustainable energy sources, fuel cells that convert chemical energy of hydrogen, natural gas, and alcohols directly to electricity have become a hot research topic worldwide.  Current energy technologies that use fossil fuels, such as diesel, coal and oil, face many challenges, among them, low efficiency, limited supply, air pollution, and climate change.  Yet, to date, renewable energy still accounts for less than 3% of all electricity produced worldwide.

Power density record
Prof Zhao, also Director of the HKUST Energy Institute, and his researchers have become global pioneers in raising the performance of Direct Alcohol Fuel Cells (DAFC).  Among other achievements, his group holds the internationally acknowledged world record for the power density of direct ethanol fuel cells.

Such work has brought Prof Zhao numerous honors and awards in the past 10 years.  These include the State Natural Science Award (Second Class) in 2012 and 2013, among the most prestigious scientific honors in China, for projects focusing primarily on heat transfer and innovations in fuel cells, respectively.  He has also been awarded a Croucher Senior Research Fellowship.

"Energy is a challenging area because of its strong multidisciplinary nature, but this also makes it both interesting and rewarding,” said Prof Zhao, who has been involved in the field since taking up engineering thermophysics at Tianjin University as a student.  “It is also hugely significant for us all."

Key advance
Prof Zhao’s major advance has been to combine thermo-fluid science and electrochemistry, which used to be two separate disciplines, to create an interdisciplinary framework for research.  This way, complex physical and chemical processes such as electron and ion transport, mass and heat transport and electrochemical reactions can be realized to efficiently generate electricity.

"Fuel cells surpass existing energy choices as they are cleaner, more efficient, sustainable and cost-effective,” he explained.  “For example, the necessary fuel can be generated from common plant sources, such as tangerines or sugar cane.”

Looking ahead
Prof Zhao foresees that the new fuel cell could make mobile phone batteries last twice as long and improve computers, appliances, and electric cars, among other applications.  He hopes that the new technology can be marketed in around seven to eight years, following further research to increase their efficiency, reduce production costs and extend their lifespan.

As Director of the HKUST Energy Institute, Prof Zhao is also encouraging interdisciplinary research on energy sustainability, efficiency and conservation, including bio-energy, solar cells, smart grid, fuel cells, energy storage and thermal management.

■  Prof Tianshou Zhao will introduce the concept of fuel cells at a Science for Lunch talk on 16 May at HKUST Business School Central.  Registration opens one month before the talk. Visit http://science-for-lunch.ust.hk for further details and online registration.

A more sustainable, cost-effective energy source.