A microfibre fabric that generates enough of its own electricity to recharge a mobile phone or ensure that an mp3 player never runs out of power, US scientists say.

If made into a shirt, the fabric could harness power from its wearer simply walking around or even from a slight breeze, they report today in the journal Nature.

"The fibre-based nanogenerator would be a simple and economical way to harvest energy from the physical movement," says Professor Zhong Lin Wang of the Georgia Institute of Technology, who led the study.

The nanogenerator takes advantage of the semiconductive properties of zinc oxide nanowires, tiny wires 1000 times smaller than the width of a human hair, embedded in the fabric.