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The quarter-sized energy harvester is small enough for use in car tires and home appliances. (Photo courtesy MicroGen Systems)
By drawing energy from vibrations, tiny sheets of piezoelectric material can provide free power to anything that moves or shakes. The battery-less sensors can take the motion from a car on bumpy asphalt or a loaded clothes dryer, for example, to give supplemental energy to a device.
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The piezoelectric unit in motion from a 60 Hz vibration. (Photo courtesy Cornell University)
Piezoelectric technology has been around since the late 19th century and can be found in microphones and phonographs working under simple principles. Under kinetic stress, crystals on a sheet of piezoelectric material become electrically polarized, which produces energy.
The new sensors, developed by MicroGen Systems and Cornell University researchers at the school’s NanoScale Facility, pair with a thin-film battery to apply the same principles, giving a boost to any attached device.
Unfortunately, a vibration-only drive in a Nissan Leaf from L.A. to New York isn’t an option. The piezoelectric system produces only 200 microwatts of energy, but the added juice could reduce drain on our gadgets’ precious power supply.