Sparks fly from friction to power the future
New developments could see the end of giant coal, gas or nuclear turbines, and the rise of electricity gathered by simple movement and friction.
For over one hundred years, the primary way to turn mechanical energy into electricity has been through the spinning of a turbine, but recent advances in piezoelectric power – electricity from pressure - have shown that there are many ways to go about it.
Researchers at the Georgia Institute of Technology were recently working on a new piezoelectric generator, but the prototype put out considerably more ower than expected.
It turned out that a particular combination of two polymer surfaces in the device were rubbing together, producing a ‘triboelectric effect’ — known to many as static electricity.
Building on the discovery, the team has now created the first ‘triboelectric nanogenerator’, or “TENG”.
TENG is essentially a pair of sheets made from two different materials.
When they rub together - one donates electrons and the other accepts them. When the sheets touch, electrons flow from one to the other. When the sheets are separated, a voltage develops between them.
Now with one stomp of his foot, Georgia’s Professor Zhong Lin Wang can light up a sheet of one thousand LEDs.
The group has already built TENG into shoes, whistles, foot pedals, floor mats, backpacks and ocean buoys for a variety of exciting applications.
The gadgets can harness the power of everyday motion from the minute (vibrations, rubbing, stepping) to the worldwide and virtually endless motion of waves.
Careful design is the fundamental factor making TENG possible, and which will drive future developments.
“The amount of charge transferred depends on surface properties,” Wang explained.
“Making patterns of nanomaterials on the polymer films' surfaces increases the contact area between the sheets and can make a 1,000-fold difference in the power generated.”
The possible uses for the technology are vast; from powering medical implants from the motion of the body, to mobile phones that charge themselves just by being in a pocket.
On a larger scale the engineers envisage using the technology to tap into the endless power of ocean waves, rain drops and the wind - with tiny generators rather than towering turbines.
More information is available in the following video;