Eco Tech: Duke University engineers to develop system to harvest nature’s motions

duke university piezoelectric device

Eco Factor: Non-linear devices to harvest energy from a wide range of frequencies.

The need to devise machines that harvest energy from renewable sources has tempted researchers to think of systems that can harness energy from motion and convert it into precious electricity. While most of these devices, dubbed linear devices, work over a narrow band of frequencies, researchers at Duke University are developing a novel approach that they believe can help generate energy from the motions of everyday life.

Working on a device that could convert a range of vibrations instead of just a narrow band into energy, the team has constructed a deceptively simple device, which is basically a small cantilever, several inches long and a quarter inch wide, with an end magnet that interacts with nearby magnets.

The magnets are used to tune the bandwidth of the experimental device, where it reacts with nearby magnets. The cantilever base itself is made of piezoelectric material that produces electricity when it is strained. By changing the distance between the movable magnets of opposing poles on either side of the magnet at the end of a cantilever arm, that allows the device to produce electricity over a broader spectrum of frequencies.

The device, according to the team, can provide energy from a wide range of sources to power different devices, while the motion of walking could provide energy to fuel an implanted device. Simple tweaking could make it generate electricity for sensors in the environment.

Via: Science Daily