Video: A new device can generate power from the movement of humans and hamsters

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Why rely on batteries when the world is full of objects just waiting to be harnessed as power generators?

Materials scientist Zhong Lin Wang at the Georgia Institute of Technology is showing the way with his gadget that can transform a hamster in its wheel or a moving human finger into a tiny electrical generator.

The hamster shown in the video above wears a backpack containing a piezoelectric nanowire attached to a pair of metal electrodes. As the tiny rodent runs, its back distorts the nanowire and generating an alternating current.


Right now this only produces 0.2 volts at half a nanoamp of current, but Wang says adding more nanowires to the device, or using multiple hamsters could offer a useful amount of power. His paper doesn’t have any solution to the problem of the hamster stopping to groom itself or snack on a few seeds.

Power typing

Strapping the device to human fingers might provide a more reliable power source, see video above. A touch-typist wearing a pair of gloves incorporating this technology could presumably generate a modest amount of personal power each day. In fact, once you start looking at the world this way, opportunities for this kind of parasitic power appear everywhere.

Last year, Wang developed an electricity-generating thread from zinc oxide nanowires. When the thread is woven into a yarn it could provide enough juice to charge a cellphone, he says.

Other working prototype devices include a pacemaker that harvests energy from heartbeats, and a device that straps to your knee to generate power as the joint straightens and decelerates during the “braking” phase of each walking step. Its inventors liken this approach to the regenerative braking that reclaims power as an electric or hybrid vehicle slows.

Perhaps, like cars, humans too will become hybrid power sources in future going some way to solve the problem of battery technology limiting portable devices like cellphones. Knees, hearts and fingers could just be the tip of the iceberg – there are many more joints and moving parts in the body ripe for exploitation. The question is, which have the most to offer?

Journal reference: Nano Letters (DOI: 10.1021/nl803904b)