In a first, scientists have created a bio-solar panel that generates electricity from photosynthesis and respiratory activities of cyanobacteria, or blue-grean algae, and can run small devices in remote areas where regular battery replacement is not possible. Researchers connected nine biological-solar (bio-solar) cells into a panel that continuously produced electricity from the panel and generated the most wattage of any existing small-scale bio-solar cells - 5.59 microwatts.
“Once a functional bio-solar panel becomes available, it could become a permanent power source for supplying long-term power for small, wireless telemetry systems as well as wireless sensors used at remote sites where frequent battery replacement is impractical,” said Seokheun Choi, an assistant professor at Binghamton University in US.
“This research could also enable crucial understanding of the photosynthetic extracellular electron transfer processes in a smaller group of microorganisms with excellent control over the microenvironment, thereby enabling a versatile platform for fundamental bio-solar cell studies,” said Choi.
The current research is the latest step in using cyanobacteria (which can be found in almost every terrestrial and aquatic habitat on the planet) as a source of clean and sustainable energy. Last year, the group took steps toward building a better bio-solar cell by changing the materials used in anodes and cathodes (positive and negative terminals) of the cell and also created a miniature microfluidic-based single-chambered device to house the bacteria instead of the conventional, dual-chambered bio-solar cells.
However, this time the group connected nine identical bio-solar cells in a 3x3 pattern to make a scalable and stackable bio-solar panel. The panel continuously generated electricity from photosynthesis and respiratory activities of the bacteria in 12-hour day-night cycles over 60 total hours.
“Bio-solar cell performance has improved significantly through miniaturising innovative device architectures and connecting multiple miniature cells in a panel,” researchers said. A typical “traditional” solar panel made up of 60 cells in a 6x10 configuration, generates about 200 watts of electrical power at a given moment. The cells from this study, in a similar configuration, would generate about 0.00003726 watts.
It is not efficient just yet, but the findings open the door to future research, researchers said. “The metabolic pathways of cyanobacteria or algae are only partially understood, and their significantly low power density and low energy efficiency make them unsuitable for practical applications,” Choi said. “There is a need for additional basic research to clarify bacterial metabolism and energy production potential for bio-solar applications,” Choi said. The findings will be published in the journal Sensors and Actuators B: Chemical.