In Canada, University of British Columbia researchers found a cheap, sustainable way to build a solar cell using bacteria that convert light to energy. Their cell generated a current stronger than any previously recorded from such a device, and worked as efficiently in dim light as in bright light.
This innovation could be a step toward wider adoption of solar power in places like British Columbia and parts of northern Europe where overcast skies are common. With further development, these solar cells—called “biogenic” because they are made of living organisms—could become as efficient as the synthetic cells used in conventional solar panels.
The UBC researchers genetically engineered E. coli to produce large amounts of lycopene—a dye that gives tomatoes their red-orange color and is particularly effective at harvesting light for conversion to energy. The researchers coated the bacteria with a mineral that could act as a semiconductor and applied the mixture to a glass surface. With the coated glass acting as an anode at one end of their cell, they generated a current density of 0.686 milliamps per square centimetre—an improvement on the 0.362 achieved by others in the field.