With the world looking for solutions to battle both rising costs of energy and the ongoing climate emergency, researchers at the University of Cambridge have hit upon a most unusual alternative to lithium-ion batteries for fueling small devices: photosynthetic bacteria.
In a report published in the journal Nature Minerals, Dr. Jenny Zhang of Cambridge’s Yusuf Hamied Department of Chemistry and her team discovered that sun-loving bacteria grew more rapidly if housed in 3D-printed “skyscrapers.” In doing so, the properly housed bacteria produce a higher amount of energy from photosynthesis which researchers have extracted and used for powering small-scale electronics.
It is an entirely different approach from many bioenergy experiments done by other institutions yet compares favorably with many traditional modes of bioenergy generation. Zhang went so far as to say that the discovery may lead to “biohybrid” power solutions to harness solar energy.
Given how this nano-tower approach has reached a certain level of solar conversion efficiency, it may soon outcompete many of the methods currently used for the generation of biofuels.
What Do We Have So Far?
Many of today’s renewable generation technologies have successfully shown their superiority to the fossil fuels still being used throughout the world. Renewables like silicon-based cells and responsibly-generated biofuel performed better in terms of carbon emissions, leaving a significantly smaller carbon footprint than more conventional power sources.
However, renewables are also hemmed in by a slew of limitations. This includes their reliance on mined elements, issues regarding the recycling of their components as in the case of batteries for electric vehicles, and the vast amount of land required to set up solar grids and wind farms. Unfortunately, all these have compromised biodiversity in many areas around the world.
That said, Zhang gave the public the assurance that she and several colleagues from Cambridge’s Department of Biochemistry and Department of Materials Science and Metallurgy are doing their best to create more sustainable and scalable bioenergy solutions.
As she puts it, there is currently a bottleneck regarding just how much energy can be extracted from bacteria-centric photosynthetic systems. Over the years, scientists surmised that the block was on the bacteria’s side; Zhang has since discovered that the material side of the equation is probably where the problems originate.
To resolve this issue, Zhang’s team custom 3D-printed electrodes crafted from metal oxide nanoparticles were specifically made to work with cyanobacteria, aiding the microorganisms throughout the photosynthetic process, allowing for a balance between surface are and light. Once the cyanobacteria acclimatized to their new home, they proved to be more efficient in producing bioenergy.
The project is in its early days, but Zhang is confident that further work will lead to a highly scalable solution.