Scientists at the Lawrence Berkeley National Laboratory (Berkeley Lab) have created a harmless, genetically-modified virus that’s piezoelectric — in other words, it generates electricity when pressure is applied. This virus might eventually find its way into piezoelectric generators in the sole of your shoe, which would generate electricity (for your smartphone) while you walk.

The concept of piezoelectric energy harvesting is hardly new, but according to Berkeley Lab the materials used to make piezoelectric devices are toxic, and are thus no good for internal use or for consumer-facing applications (such as the aforementioned shoe-sole power generator). The The M13 bacteriophage (literally “bacteria devourer”) virus, however, is: piezoelectric, harmless to humans, easy to genetically modify, and readily aligns itself into an orderly film — and, being a virus, it readily replicates itself millions of times, so you don’t need to worry about running out of juice at an inopportune moment.

To turn the M13 phage into into a power source, the scientists genetically engineered the virus to create a higher voltage, stacked 20 layers of the virus on top of a gold substrate, attached some wires, and voila: a piezoelectric generator that produces no less than six nanoamperes at 400 millivolts. This might not sound like a lot (OK 6 nA isn’t a lot), but in the video below you can see that it’s enough to power a simple LCD display — or, alternatively, a low-power sensor.

Ultimately, the most exciting aspect about piezoelectricity is that it can be generated from almost any “wasted” movement — this could be as obvious as swinging your legs and feet, but piezoelectric generators could also harvest power from dance floors, the office stairs, or the vibrations from heavy machinery.

It’s also worth bearing in mind that a self-assembling piezoelectric generator is rather desirable — especially in today’s world, where mass production of genetically modified viruses is a lot easier than rearranging individual atoms with a scanning tunneling microscope. Byung Yang Lee, one of the scientists behind the discovery, says, “We’re now working on ways to improve on this proof-of-principle demonstration… piezoelectric materials based on viruses could offer a simple route to novel microelectronics in the future.”

Read more at Berkeley Lab (or read the paper at Nature [non-paywalled!!])