Walking may be the purest form of transportation. Of course, if you haven't gotten out and about in a while you may face some range anxiety, but walking is undoubtedly one of the cleanest, most reliable ways to travel short distances. If, however, the satisfaction that comes with a bit of exercise and fresh air isn't enough to dissuade you from hopping in your car for that jaunt to the corner store, perhaps this will: walking could soon power the electronic devices you can't leave home without. ScienceNOW reports that two University of Wisconsin researchers have developed an energy-harvesting apparatus that attaches to the insole of your shoe. The device converts the mechanical motion of walking into electrical power through the use of conductive materials. Specifically, a metal electrode plate rests atop a conductive substrate plate, with droplets of electrically conductive liquid sandwiched between the two and held in place by an elastic spacer. As you walk, the plates either compress or slide against one another, generating electrical power. The electrode is connected to a circuit which harvests the voltage produced by your casual stride.
Researchers claim that a person could completely recharge a "standard" cell phone over the course of a 2 hour ramble. Granted, most casual walks don't last nearly that long, but if a 15 minute stroll could provide just enough juice to finish a phone conversation, music playlist, or snap a few more photos, we can think of many instances where energy-harvesting shoes could come to the rescue.
[Source: Nature Communications via ScienceNOW]
We couldn't help but be reminded of these embarrassing sneakers from our youth: