A Virus That Helps Charge Your CellphoneBy JIM WITKIN
Scientists at the Energy Department’s Lawrence Berkeley National Laboratory say they have created a virus that generates electricity . The research is described as a first step toward using genetically engineered viruses to build devices that convert the body’s motion into electricity.
Such personal power generators — compact, wafer-thin devices attached to clothing or inserted in shoes — could produce enough electricity to power cellphones or other small electronic gadgets, said the project’s chief investigator, Seung-Wuk Lee.
This piezoelectric method for producing power by converting mechanical force or motion to electricity is already widely used in cars and a number of manufacturing processes. Cigarette lighters and starters on gas grills rely on piezoelectricity. For example, pushing the starter button on the grill generates a small electric current that creates a spark and ignites the gas. Even more creative uses can now be found in things like soccer balls and dance floors.
But this is the first time that a biological material has been used for piezo generators, according to the researchers, who add that a virus offers several advantages over the inorganic, ceramic materials regularly used today. Ceramic materials can be difficult to work with and create toxic byproducts during their manufacture and use. By contrast, virus-based piezoelectric materials “potentially offer a simple and environmentally friendly approach to piezoelectric energy generation,” Dr. Lee said.
The viruses replicate themselves, providing a steady supply of material, and they naturally organize into well-ordered films, an important property for nanotechnology devices.
The Berkeley Lab researchers started with the M13 virus, which is harmless to humans and commonly used in lab experiments, Dr. Lee said. They genetically modified the M13 to enhance its piezoelectric properties, then created a thin film of the material about the size of a postage stamp. The film was then placed between two gold-plated electrodes. When pressure was applied, it produced enough current to light up an LED display — about one-fourth the voltage of a triple-A battery. (See the video below.)
While the research clearly demonstrates that viral electricity is a viable concept, you won’t see these types of microgenerators available for sale anytime soon. “Our investigation is still in the fundamental scientific discovery level,” Dr. Lee said. If the research is successful, he added, it might be possible to power small microelectronic devices in five to 10 years. The technology could also be used to power biomedical devices like pacemakers by implanting the tiny virus-based generators in patients.
The research team is also experimenting with interconnecting the piezoelectric micro generators to increase the electrical output and potentially power bigger things. “We do not know the upper limit” for constructing such devices, Dr. Lee said, “but we are in the middle of optimizing the power output, and it looks very promising.”