Researchers have suggested that air flowing around a moving vehicle could help generate electricity for use in cars and planes.
They are developing and improving the efficiency of inch-long devices that can harness the energy of motion and convert it into electricity.
Known as piezoelectrics, the devices can be mounted on a car roof or aircraft fuselage. Although unable to power engines, they could drive electrical systems for dashboard or cockpit instruments. Air flowing around a moving vehicle causes internal vibrations that would produce an output voltage.
The devices are being developed by a City College of New York team headed by Professor Yiannis Andreopoulos.
He said: "These devices open the possibility to continuously scavenge otherwise wasted energy from the environment."
They are studying two approaches that involve causing the device to vibrate "in resonance" with the air flow, or shake around in turbulence.
Data from wind tunnels and other research from the project were presented at the annual meeting of the American Physical Society's Division of Fluid Dynamics in Minneapolis, US.
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