A group of scientists in the United States has a plan that will boost the
run time of small gadgets like phones a MP3 players to possibly unlimited
proportions, without the need for batteries. The scientists hope to do this
with fabric that generates its own electricity.
The idea is that fiber-based
nanogenerators would be woven into the fabric of a shirt and the friction
cause by moving around would be transferred into energy to power the device.
Scientists even say that simply standing in a breeze could generate all the
power your iPod needs to play indefinitely.
Zhong Lin Wang of the Georgia Institute of Technology, the leader of the
study researchers, said, “The fiber-based nanogenerator would be a simple and
economical way to harvest energy from the physical movement.”
According to Reuters, the nanogenerator wires generate electricity by
taking advantage of the semiconductive properties of zinc oxide nanowires. Each
of the nanowires is about 1,000 times smaller than the width of a human hair.
These nanowires are formed into pairs that resemble a microscopic bottle
brush and when they rub together electricity is generated. One of the fibers in
each pair is coated with gold to serve as an electrode.
Wang told Reuters, “When a nanowire bends it has an electric effect.
What the fabric does is it translates the mechanical movement of your body into
electricity.”
The tiny nanogenerators were created by the researchers by coating fibers
with a polymer and adding a layer of zinc oxide when was then covered again
with a polymer to keep the zinc from coming off. Current is produced only when
the gold coated fibers and zinc oxide fibers brush together.
According to Wang, the researchers estimate that a fabric made with this
process would generate around 80 mW of power per square meter of fabric. The
researchers see the technology being used by hikers and soldiers in the field
to power sensors and other electronic devices.
Wang and his team have a major hurdle to overcome before the technology can
be put into use. The zinc oxide required to create the electricity degrades
when it gets wet. Research into a type of coating that will keep the zinc oxide
from degrading in the wash or rain is underway.
If the researchers sort out the water issue coupling this electricity
generating fabric with the LED
fabric Philips demonstrated in 2007 could yield some interesting garments.