One of the principal arguments that solar energy comes up against is its obvious dependence on sunlight - and for places that don’t receive much, or consistent sun, this form of renewable energy is basically unviable. But researchers from the University of British Columbia in Canada have recently discovered a loophole that may make harnessing solar power possible even on those gray days.
"Our solution to a uniquely B.C. problem is a significant step toward making solar energy more economical," said Vikramaditya Yadav, a professor in UBC's department of chemical and biological engineering who led the project.
Using bacteria in order to convert light to energy, the research team developed a solar cell that is capable of generating a strong current even in “dim light” days, such as those experienced much of the year in British Columbia or England. And to make it better, it’s cheap.
Called “biogenic” solar cells, this living technology has the potential to become just as widely used as conventional solar panels. Because solar panels are essentially composed of solar cells, scientists in the past have tried to create similar technologies, by extracting the naturally-occurring dye that bacteria need for photosynthesis to convert light into electrical currents. But past attempts have been too complex and expensive. What the UBC team did, instead, was keep the dye in the bacteria and use a genetically engineered version of E. coli to produce a dye called lycopene that is really good at converting light into energy. “This modification yields a strain that overproduces the photoactive pigment lycopene,” write the authors. Science Daily explains the process and magnificent results:
“The researchers then coated the bacteria with a mineral that could act as a semiconductor, and applied the mixture to a glass surface.W ith the coated glass acting as an anode at one end of their cell, they generated a current density of 0.686 milliamps per square ccentimeter-- an improvement on the 0.362 achieved by others in the field.”
Yadav was excited about the outcomes from the team’s hard work. "We recorded the highest current density for a biogenic solar cell. These hybrid materials that we are developing can be manufactured economically and sustainably, and, with sufficient optimization, could perform at comparable efficiencies as conventional solar cells," Yadav commented.
The authors have significant hope for what lays ahead in the development of this biogenic solar cell. An obvious advantage is the great reduction in costs - Yadav estimates the process cuts costs to about one-tenth of the original dye production process. But the technology also holds possibilities for biogenic materials in mining, deep-sea exploration and other low-light environments. More research will need to be conducted in order to determine the extent of biogenics .
Sources: Science Daily, Nano Micro Small