The phenomenon that causes a painful shock when you touch metal after dragging your shoes on the carpet could someday be harnessed to charge personal electronics.

Researchers at Georgia Tech have created a device that takes advantage of static electricity to convert movement—like a phone bouncing around in your pocket—into enough power to charge a cell phone battery. It is the first demonstration that these kinds of materials have enough oomph to power personal electronics.

Excess energy produced when you walk, fidget, or even breathe can, in theory, be scavenged to power medical implants and other electronics. However, taking advantage of the energy in these small motions is challenging.

Zhong Lin Wang, a professor of materials science at Georgia Tech, has been working on the problem for several years, mostly focusing on piezoelectric materials that generate an electrical voltage under mechanical stress (see “Harnessing Hamster Power with a Nanogenerator”). Wang and others have amplified the piezoelectric effect by making materials structured at the nanoscale. So far, though, piezoelectric nanogenerators have not had very impressive power output.