The technology of triboelectric nanogenerators (TENG) has come a long way since its unveiling only two years ago, based on the creator’s most recent press release. Since then, the technology has had its power output density boosted by a factor of over 100,000 — the power output now reaches up to, impressively, 300 Watts per square meter.
To better explain the improvements, you can simply note the fact that a single stomp of your foot would be enough to light up a sheet of over a thousand LED bulbs.
The promise of this interesting technology is of course the great possibilities with regard to portable electronics — cellphones that charge themselves while resting in your pocket, etc — but there is actually a great deal more that can be done with the technology, as the creators note. Anything from capturing the energy of falling raindrops to that of crashing waves.
Currently though, the researchers are ‘simply’ working on the commercialization of products to recharge cell phones and other mobile devices.
The press release provides some background on the technology:
A couple of years ago, Zhong Lin Wang’s team at the Georgia Institute of Technology was working on a miniature generator based on an energy phenomenon called the piezoelectric effect, which is electricity resulting from pressure. To their surprise, it produced more power than expected. They investigated what caused the spike and discovered that two polymer surfaces in the device had rubbed together, producing what’s called a triboelectric effect — essentially what most of us know as static electricity.
Building on that fortuitous discovery, Wang then developed the first triboelectric nanogenerator, or “TENG.” He paired two sheets of different materials 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.
Since that initial discovery the researchers have greatly increased the power output density (as previously stated) and have also incorporated TENG into a wide variety of common everyday items, including: shoe insoles, whistles, foot pedals, floor mats, backpacks and ocean buoys, etc.
In these contexts, the gadgets work to effectively harness the “power of everyday motion from the minute (think vibrations, rubbing, stepping) to the global and endless (waves).”
With regard to how the recent big improvements were made, Wang states: “The amount of charge transferred depends on surface properties. 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.”