Researchers work to harvest electricity from plants

During photosynthesis, plants use sunlight to split water atoms into hydrogen and oxygen, which produces electrons. These newly freed electrons go on to help create sugars that plants use like food to support growth and reproduction. "We have developed a way to interrupt photosynthesis so that we can capture the electrons before the plant uses them to make these sugars," said project leader Ramaraja Ramasamy. The team's method involves separating out structures in the plant cell called thylakoids, which are responsible for capturing and storing energy from sunlight. By manipulating the proteins contained in the thylakoids, the pathway along which electrons flow can be interrupted. These modified thylakoids are then immobilised on a specially designed backing of carbon nanotubes, cylindrical structures that are nearly 50,000 times finer than a human hair. The nanotubes act as an electrical conductor, capturing the electrons from the plant material and sending them along a wire. In small scale experiments, the team's approach was said to result in electrical current levels two orders of magnitude larger than those previously reported in similar systems. "In the near term, this technology might best be used for remote sensors or other portable electronic equipment that requires less power to run," Ramasamy said. "If we are able to leverage technologies like genetic engineering to enhance stability of the plant photosynthetic machineries, I'm very hopeful that this technology will be competitive to traditional solar panels in the future."