A new advancement in solar cells could enable solar power in areas plagued by frequent overcast skies.
Scientists from the University of British Columbia (UBC) have developed a cheaper and sustainable method to build biogenic solar cell, using bacteria that converts light to energy and generates a current stronger than any previously recorded from a solar cell, while efficiently dimming light.
The researchers believe the discovery could eventually lead to solar cells that are as efficient as the synthetic cells used in conventional solar panels.
“Our solution to a uniquely B.C. problem is a significant step toward making solar energy more economical,” Vikramaditya Yadav, a professor in UBC’s department of chemical and biological engineering who led the project, said.
Solar cells convert light into electrical current for solar panels. Previously, scientists have attempted to build biogenic solar cells by extracting the natural dye that bacteria use for photosynthesis. However, this process is both costly and complex because it involves toxic solvents and can cause the dye to degrade.
The researchers opted to leave the dye in genetically engineered E. coli that can produce large amount of lycopene—a dye that gives tomatoes their color and is effective at harvesting light for conversion to energy. They then coated the bacteria with a mineral that acts as a semiconductor.
The team applied the mixture to a glass surface that acts as an anode at one end of the cell, generating a current density of 0.686 milliamps per square centimeter. This represents an improvement on the 0.362 milliamps per square centimeter achieved by others in the field.
“We recorded the highest current density for a biogenic solar cell,” Yadav said. “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.”
The researchers believe that the new process could reduce the cost of dye production to about 10 percent of what it would be otherwise. However, if they can develop a process that does not kill the bacteria, they could produce dye indefinitely.
Along with improved solar cells, the biogenic materials could be used in a number of applications, including mining, deep-sea exploration and other low-light environments.
The study was published in Small.
