Soon, plants to help generate electricity

Researchers, including an Indian-origin scientist, have found a novel way to harvest solar power to generate electricity, by stealing the energy from plants.
The Sun provides the most abundant source of energy on the planet. However, only a tiny fraction of the solar radiation on Earth is converted into useful energy.
"Clean energy is the need of the century," said Ramaraja Ramasamy, assistant professor in the University of Georgia College of Engineering and the corresponding author.
"This approach may one day transform our ability to generate cleaner power from sunlight using plant-based systems," said Ramasamy.
Plants are the undisputed champions of solar power. After billions of years of evolution, most of them operate at nearly 100 per cent 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 per cent.

"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 Ramasamy.
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 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, this approach resulted in electrical current levels that are two orders of magnitude larger than those previously reported in similar systems.
Ramasamy cautions that much more work must be done before this technology reaches commercialisation, but he and his collaborators are already working to improve the stability and output of their device.
"In the near term, this technology might best be used for remote sensors or other portable electronic equipment that requires less power to run," he said.

The study was published in the Journal of Energy and Environmental Science.