MrSeb writes "An international team of engineers, physicists, and chemists have created the first fiber-optic solar cell. These fibers are thinner than human hair, flexible, and yet they produce electricity, just like a normal solar cell. The U.S. military is already interested in weaving these threads into clothing, to provide a wearable power source for soldiers. In essence, the research team started with optical fibers made from glass — and then, using high-pressure chemical vapor deposition, injected n-, i-, and p-type silicon into the fiber, turning it into a solar cell (abstract). Functionally, these silicon-doped fiber-optic threads are identical to conventional solar cells, generating electricity from the photovoltaic effect. Whereas almost every solar cell on the market is crafted out of 2D, planar amorphous silicon on a rigid/brittle glass substrate, though, these fiber-optic solar cells have a 3D cross-section and retain the glass fiber's intrinsic flexibility. The lead researcher, John Badding of Penn State University, says the team has already produced 'meters-long fiber,' and that their new technique could be used to create 'bendable silicon solar-cell fibers of over 10 meters in length.' From there, it's simply a matter of weaving the thread into a fabric."