Wednesday, February 18, 2009

"ENERGY: nanowires generate energy from muscle movement"

The demonstration required a hamster to wear a jacket with a built-in nano-generator, but the running critter showed that almost any movement can be harnessed to generate electricity to power electronic devices. Researchers at Georgia Tech, which conducted the demonstration, predict nanoscale piezoelectric energy generators could power mobile phones and other handhelds using the energy harvested from the environment. In the near term, researcher Zhong Lin Wang said he wants to power medical nanodevices with muscle movements such as flexing fingers and vibrating vocal cords.

BOTTOM LINE: Piezoelectric nanowires generate energy when they are bent, making them a natural for harvesting power for mobile phones and other portable electronics. Unfortunately, the small size of the nanowire (nanometers thick and only microns long) means the amount of power generated by each one is miniscule--less than a nanoamp--which means you need millions in parallel to power real devices. In principle, they can be woven together into sheets or even garments, harvesting everyday movements to recharge your mobile devices, but it may take a decade of hard engineering work to realize this dream.