Reports out of the journal Nature suggest that scientists are close to creating a way to make our clothes work for us, beyond keeping us fashionable and warm. By using the piezoelectric effect, by which electricity is generated when normal amounts of pressure are applied to certain materials, scientists claim that simple friction of fabric can create energy in the amount of 80 milliwats (enough to charge your iPod). We’re talking about normal wear and tear, folks.
The Seattle Times explains it much better than I:
While the piezoelectric effect has been understood at least as far back as the 19th century, it is getting creative new looks, as concerns about energy supplies are inspiring quests for alternative power sources.
For example, a Japanese railway has experimented with mats, placed under turnstiles, that translate the pressure from thousands of commuters' footfalls into usable power. French scientists have proposed capturing energy from raindrops hitting a structure with piezoelectric properties.
For the research described in Nature, Zhong Lin Wang and colleagues at the Georgia Institute of Technology covered individual fibers of fabric with nanowires made of zinc oxide. These wires are 50 nanometers in diameter, 1,800 times thinner than a human hair.
Alternating fibers are coated with gold. As one strand of the fabric is stretched against another, the nanowires on one fiber rub against the gold-coated ones on the other, like the teeth of two bottle brushes. The resulting tension and pressure generate a piezoelectric charge that is captured by the gold and can be fed into a circuit.
Now that is an investment I could support.