Claimed to be five times more efficient than current plant-powered models, the new greener fuel cells is a type of biophotovoltaic (BPV), a solar cell capable of converting solar energy into electricity using biological mechanisms.

Researchers said that biophotovoltaics, or biological solar-cells have emerged as environmentally-friendly cell in recent years, as they use photosynthetic abilities of microorganisms like algae to harness the power of the sun.

The new technique developed by the researchers includes a  two-chamber BPV system that allows for the seperation of the two core processes involved in the operation of a solar cell. 

The researchers said that building a two-chamber system allowed to design the two units independently, thus optimizing the performance of the processes simultaneously.

Cambridge University chemistry department professor Tuomas Knowles said: “Separating out charging and power delivery meant we were able to enhance the performance of the power delivery unit through miniaturization.

 “At miniature scales, fluids behave very differently, enabling us to design cells that are more efficient, with lower internal resistance and decreased electrical losses.”

The research team used genetically modified algae to carry mutations that allows the cells to minimise the amount of electric charge dissipated non-productively during photosynthesis.

Together with the new design, the researchers have been able to build a biophotovoltaic cell with a power density of 0.5 W/m2, five times that of their previous design. 

Cambridge University biochemistry department Professor Christopher Howe said: “In particular, because algae grow and divide naturally, systems based on them may require less energy investment and can be produced in a decentralized fashion."

The project is backed by the Leverhulme Trust, the Engineering and Physical Sciences Research Council and the European Research Council.

Image: Cambridge University researchers have developed a more efficient algae-powered fuel cell. Photo: courtesy of University of Cambridge.