Imagine generating electricity in your footsteps. Sounds utopian. But,this could soon be a reality,say scientists who have developed a paper-thin generator that harnesses the mechanical energy of one’s steps.
An international team says these “living generators” use viruses to convert the soles of one’s shoes into electricity.
So far,the generators can only create enough power to run a small LCD panel (about a quarter of the power of a AAA battery) — but work in the laboratory simply by tapping a finger on an electrode,the ‘Daily Mail’ reported.
In the future,the scientists could be used to power everything from portable electronics like phones powered by footsteps — to lighting systems,powered by similar panels inside doors.
The viruses are harmless — built to “harness” physical stress in an object to generate electricity. The technology already works — at least in the laboratory,say scientists at the US Department of Energy’s Lawrence Berkeley National Lab.
They tested their approach by creating a generator that produces enough current to operate a small liquid-crystal display. It works by tapping a finger on a postage stamp-sized electrode coated with specially engineered viruses.
The viruses convert the force of the tap into an electric charge. This generator is the first to produce electricity by harnessing the piezoelectric properties of a biological material.
Piezoelectricity is the accumulation of a charge in a solid in response to mechanical stress. The milestone could lead to tiny devices that harvest electrical energy from the vibrations of everyday tasks such as shutting a door or climbing stairs,the ‘Nature Nanotechnology’ reported.
“More research is needed,but our work is a promising first step toward the development of personal power generators,and other devices based on viral electronics,” said Seung-Wuk Lee of the Berkeley Lab.
Lee and colleagues wondered if a virus studied in labs worldwide offered a better way. The M13 bacteriophage only attacks bacteria and is benign to people. Being a virus,it replicates itself by the millions within hours,so there’s always a steady supply.
The scientists further enhanced the system by stacking films composed of single layers of the virus on top of each other. They found that a stack about 20 layers thick exhibited the strongest piezoelectric effect.
The only thing remaining to do was a demonstration test,so the scientists fabricated a virus-based piezoelectric energy generator.
They created the conditions for genetically engineered viruses to spontaneously organise into a multilayered film that measures about one square centimetre. This film was then sandwiched between two gold-plated electrodes,which were connected by wires to a liquid-crystal display.
When pressure is applied to the generator,it produces up to six nanoamperes of current and 400 millivolts of potential.
“We’re now working on ways to improve on this proof- of-principle demonstration. Because the tools of biotechnology enable large-scale production of genetically modified viruses,piezoelectric materials based on viruses could offer a simple route to novel microelectronics in the future,” Lee said.