There are a lot of things to like about solar power. It helps the world kick the fossil fuel habit, it’s clean and plentiful, and leaves no carbon footprint. But it needs the sun to work, which makes it less practical in places where overcast days are common.
A genetically engineered bacterium that uses dye to convert light to energy ultimately might change that. Scientists in British Columbia — which often has cloudy days — have built a cheap, sustainable solar cell from E. coli, creating a “biogenic” solar cell — so named because it is made of a living organism. Theirs is not the first experimental biogenic solar cell, but it’s different from the others — and it produced a more powerful current, they said. Also, it works as well in dim light as in bright light.
Any material that can be “excited” or energized sufficiently by light to release electrons can be used in solar cells to generate electricity. In biogenic solar cells, the material “excited” by light is biological — in this case, the dye — compared to conventional, or inorganic, solar cells which use crystalline silicon to generate electrons.