No need to lose your shiznit the next time you need a power outlet for a dying cellphone. Scientists at the University of Southampton are working on an energy-harvesting film that could make juicing a gadget as easy as swinging your arm or treading across a rug. Steve Beeby and his team at the university’s School of Electronics and Computer Science are using a combination of rapid printing processes and active-printed inks to screen the film directly onto fabric and textiles, including carpet. Batteries aren’t required, either. Because the film is designed to convert ambient energy in the environment—including motion and heat—into electricity it doesn’t require recharging or replacement.
Although energy harvesters (also known as energy scavengers) currently do not generate enough power for mechanical work, stealing enough useful energy to fire up mobile electronics is a comparative cinch. The large-amplitude, low-frequency movements that characterize human motion, for instance, can generate an estimated 67 watts of energy with each step.
Human motion can generate an estimated 67 watts of energy with each step.
Plundering energy from body heat, using the Seebeck effect, is just as promising. (Seiko pulled it off in 1998 with its Thermic wristwatch, the world’s first watch to be driven by body heat, or more accurately, the temperature gradient between our skin and the surrounding air.)
The film, says Beeby, will provide a low-cost, flexible, and rapid way to realize energy-harvesting textiles. And this is only the beginning: His research, which is expected to run till 2015, will examine how a range of different fabrics can be adapted to allow for bespoke design that can be tailored to specific requirements—and, presumably, survive the wash.