Plants being used as alternate source to generate electricity
Washington, May 10, 2013
First Published: 18:13 IST(10/5/2013)
Last Updated: 18:17 IST(10/5/2013)
Researchers led by an Indian origin professor at the University of Georgia are developing a new technology that will make it possible for plants to generate electricity.
A member of the horticulture team works on a display of tropical plants and flowers at the Kew Garden's Tropical Extravaganza 2012 festival in south London. AFP/Leon Neal
“Clean energy is the need of the century,” Ramaraja Ramasamy, assistant professor in the UGA College of Engineering and the corresponding author of the paper said.
“This approach may one day transform our ability to generate cleaner power from sunlight using plant-based systems,” he said.
Plants are the undisputed champions of solar power. After billions of years of evolution, most of them operate at nearly 100 percent quantum efficiency, meaning that for every photon of sunlight a plant captures, it produces an equal number of electrons.
Converting even a fraction of this into electricity would improve upon the efficiency seen with solar panels, which generally operate at efficiency levels between 12 and 17 percent.
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 much 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,” Ramasamy, who is also a member of UGA’s Nanoscale Science and Engineering Center, said.
Ramasamy’s technology involves separating out structures in the plant cell called thylakoids, which are responsible for capturing and storing energy from sunlight.
Researchers manipulate the proteins contained in the thylakoids, interrupting the pathway along which electrons flow.
These modified thylakoids are then immobilized 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, this approach resulted in electrical current levels that are two orders of magnitude larger than those previously reported in similar systems.
The research is published in the Journal of Energy and Environmental Science.