A spoon of sugar can generate 80 hours of electricity for a battery, thanks to a novel microbial fuel cell (MFC) developed by students from north China's Tianjin Municipality.
A group of 19 college and high school students led by instructors from Tianjin University worked out a three-species co-cultured system of electricity generation, which won them a gold medal and the award for the best energy project at the 2015 International Genetically Engineered Machine (iGEM) Competition.
The poor performance and limited practical application of traditional single-strain MFC inspired the team to extend their engineering capabilities to multicellular microbial consortia, according to Liu Yue, a team member and a postgraduate majoring in biological engineering.
According to Yuan Yingjin, the team instructor, this is the first time for three different species, namely E. coli, Shewanella and B. subtilis to be introduced into an MFC system.
"Every microbe has its own unique functions and responsibilities in the 'team', which reduces the metabolic burden for all the microbes, improves the transmission efficiency of electrons and provides more electricity," Liu said.
Through the electricity generation platform they designed, the final output reached over 520 mV and lasted over 80 hours. The microbes feed on organic substances such as sugar or grass.
"After technical optimization, our MFC is able to generate the same electricity output as a lithium battery, with longer battery life, lower cost and zero pollution," Yuan said.