A report published in Nature explains how textile fibers covered with zinc oxide nanowires generate electricity in response to applied mechanical stress. According to Georgia Tech professor Zhong Lin Wang “ the two fibers scrub together just like two bottle brushes with their bristles touching, and the piezoelectric-semiconductor process converts the mechanical motion into electrical energy”. A square meter of this fabric could generate as much as 80 milliwatts. There are two problems with the technology right now, first iPod need at least 8 times more power to run compared to power generated by one square meter cloth. The second problem is zinc oxide is sensitive to moisture so can’t wear those pants when its raining and you can’t wash your pants (may be dry-cleaning is the solution).