Coimmercial idea: A man clad in AT&T garb is standing on the road shouting into his telephone,“What do you mean you can’t hear me?” He looks up to see a giant cell phone tower blocking the view of the sun. He shakes his head and starts walking down the road.
“Sorry about that,” he explains. “My battery was dead so I had to start walking. Can you hear me now?”
According to scientists at the University of Wisconsin, this concept isn’t quite as far away as you might believe. According to their recent publication in Nature Communication, they believe they’ve cracked the code to harvesting enough energy from human locomotion to create one to tens of Watts per shoe – enough to power a cell phone or a personal computer.
The technology behind their claim is called reverse electrowetting, or EWOD for short. In the simplest terms I can communicate (okay okay, or understand), the idea is to take drops of a conductive liquid and let them roll around on conductive substance coated in an insulating material.
In traditional electrowetting, a charge is applied to the substance that makes it behave as an insulator and repel the liquid. Thus, in the reverse case, the motion of the liquid causes a charge to flow through the insulating coating.
The effect was discovered by the same researchers, and now they think they can stick it in your shoe. By their calculations, the material could be used in a small enough area to fit on the bottom of a shoe in a thin enough profile to not affect the way you walk. The resulting electricity could flow through wires to a converter for whatever you want to charge or – better yet – feed a small device that emits an electromagnetic field that your devices can directly utilize to charge themselves.
Notice how that last option doesn’t exactly exist yet? Well, neither really do the shoes. There is no prototype, this is just an idea on paper at the moment. And even if it does work, mobile devices would have to be built with these special adaptations in them. If someone like Apple got a hold of the technology and decided to push it hard, I could see it coming to fruition eventually. But seeing as how what most people already own doesn’t work like this, there will probably be wires involved.
Though I may not be a fan of walking around with wires in my shoes, I can certainly see the appeal of doing away with the tons of batteries used and thrown away every year. I could make a concession for the environment.