Allie laces her running shoes and then grabs her mp3 player and ear buds before rushing out the door. It's 6 a.m., and if she hurries, she can finish a run powered by a pounding playlist before she needs to shower for work. Just as Allie's hitting her stride, though, her music goes silent. Dead battery.
Whether it was during a run, an important phone call, a level-busting game of Candy Crush or your reply to a weekend-changing text, a dead battery can have consequences ranging from inconvenient to disastrous.
Thankfully, there's a new movement that could make this problem a thing of the past — and it all hinges on harvesting kinetic energy. In fact, if Allie owned a personal kinetic energy device, she could forget about dead batteries and instead power her mp3 player all by herself.
The term "kinetic energy" is based on "kineses," the Greek word for motion. A hydroelectric dam that harnesses the power of rushing water to create electricity is a form of kinetic energy. Wind turbines, which employ wind gusts to generate electricity, are another example. So is a new class of kinetic-energy charging devices, which are tapping into people's everyday activities to power their portable electronics.
One version of the personal kinetic-energy device is a cylindrical object about the size of a banana. Inside, a spring-loaded magnet travels through a lubricated channel as the wearer moves. The device acts as a micro-generator, creating a charge that is stored in the device's internal battery until it is needed to power electronic devices, such as portable music players and more. Other versions of the device have varying internal components, including silicone and a metal coil, that are used to generate battery-life-giving electrical current [source: Brownell].
Take the nPower PEG (personal energy generation), for example. According to the device's inventor, walking for one minute will power an iPod nano for one minute. Faster movements, such as running, will generate about five times the power in the same one-minute time frame. More complex devices, such as smartphones, typically can be powered on a ratio of 15 minutes of walking to one minute of charging [source: Werner].
Running-shoe-specific models of kinetic chargers can be attached to shoes or, in some cases, have already been built into the soles. An attachable model, for example, can be affixed to the top of a running shoe near the laces and, once charged by the user's movement, a USB cord can be used to attach the charger to a music player or other portable electronic device [source: Das]. This means charging your running playlist could be as simple as planning your next workout.