Tiny ’skyscrapers’ help bacteria convert sunlight into electricity

3D-printed custom electrodes Credit: Gabriella Bocchetti Researchers have made tiny 'skyscrapers' for communities of bacteria, helping them to generate electricity from just sunlight and water. Our approach is a step towards making even more sustainable renewable energy devices for the future Jenny Zhang The researchers, from the University of Cambridge, used 3D printing to create grids of high-rise 'nano-housing' where sun-loving bacteria can grow quickly. The researchers were then able to extract the bacteria's waste electrons, left over from photosynthesis, which could be used to power small electronics. Other research teams have extracted energy from photosynthetic bacteria, but the Cambridge researchers have found that providing them with the right kind of home increases the amount of energy they can extract by over an order of magnitude. The approach is competitive against traditional methods of renewable bioenergy generation and has already reached solar conversion efficiencies that can outcompete many current methods of biofuel generation. Their results open new avenues in bioenergy generation and suggest that 'biohybrid' sources of solar energy could be an important component in the zero-carbon energy mix. Current renewable technologies, such as silicon-based solar cells and biofuels, are far superior to fossil fuels in terms of carbon emissions, but they also have limitations, such as a reliance on mining, challenges in recycling, and a reliance on farming and land use, which results in biodiversity loss.