Triboelectricity: Energy that was previously neglected

Light sea ripples provide energy to thousands of homes, dancers generate electricity for the entire nightclub, away from the benefits of civilization, tourists with the power of their feet on the move recharge their smartphones. A clean and reliable, geopolitically risk-free energy source is already within reach thanks to the use of the triboelectric effect.

Researchers at the Georgia Institute of Technology said they have built a prototype of a simple device that converts start-stop motion into energy. Waves, walking and dancing, even showers or computer keys could one day be used to control sensors, mobile gadgets and even power generators, they said.

Zhong Lin Wang, professor of materials science and engineering, calls the invention a breakthrough. “Our technology can be used for large-scale energy harvesting.” Now the energy that we have been losing for centuries will be useful, he said.

Triboelectricity is known by all school experiences. It is produced by friction of two objects, causing the movement and concentration of electrons. In everyday life, the tribo effect manifests itself in static charges. Anyone can remember being electrocuted by a cat or being hit by a car door.

It is difficult to predict when and how triboelectricity will manifest itself. Therefore, until now, it was preferred not to be contacted, using as a source of electricity more predictable induction generators, rotated by steam, water or wind.

In a new study published in the journal Nature Communications, Wang’s group showed that scientists have overcome the fundamental obstacles to converting randomly generated electrical charges into current.



The prototype tribogenerator, whose purpose is to demonstrate the potential of energy harvesting, looks like a disk with a diameter of about 10 centimeters. Inside are two rotating sheets of material in the shape of a circle, one electron donor, the other their receiver. When rotating between them, an electric charge is formed, since the sheets are isolated from each other. The third disc with electrodes is located between the first two. It “takes off” the charge and provides a small electric current through the payload.

The power of the device at a maximum speed of rotation of 3000 revolutions per minute is 1.5 W. The energy efficiency of the prototype is 24%, which is comparable to the performance of magneto-induction turbines and three times higher than the efficiency of piezocrystals, previously considered the best collectors of mechanical energy.

According to Wang, the device can operate not only under the pressure of wind or water from the tap, but also from random intermittent movements that ensure rotation, including human movements. “As long as there is mechanical action, there is energy that can be generated,” he said.

Source: facepla.net