Whether your laptop gives up just as you're about to finish a crucial report or your phone kicks the bucket when you're hopelessly lost, we've all felt the pain of running out of juice when you're out and about. Which is why we love the sound of laptops that can be charged by your typing, or phones that power up as you walk -- and it's all thanks to a virus.
Devices powered by small everyday movements could come true thanks to a genetically engineered virus that turns movement or pressure into electricity.
It's the first time scientists have generated electricity by harnessing the piezoelectric properties of a biological material. The piezoelectric effect was discovered in 1880 and sees a charge build up in crystals, ceramics and even bone when placed under mechanical stress -- creating a spark in cigarette lighters or barbecues, for example.
A team of big brains at the Lawrence Berkeley National Laboratory in California set out to generate piezoelectric power from the the M13 virus, commonly found in science labs. The M13 bacteriophage only attacks bacteria and is harmless to people, unlike other materials used in piezoelectric devices.
With a quick bit of genetic tinkering to add extra negatively charged amino acid residues to one end of the helical proteins that coat the virus, the voltage of the virus is boosted.
The scientists then covered an electrode the size of a postage stamp with the genetically engineered viruses, and wired it to an LCD display. Hey presto: tap on the electrode, and the viruses convert the force of the tap into an electric charge.
Pressing on the electrode produces up to six nanoamperes of current and 400 millivolts of potential: that's about a quarter of the voltage of an AA battery.
One day we could see virus-coated keyboards juicing up our laptops, or virus-coated electrodes in our shoes powering the
lights on the heel products in our pockets. What other gadgets could be charged by small every day movements? Infect the comments or our Facebook page with your thoughts.