Nanogenerator harvests power from rolling tyres

An innovative nanogenerator developed by engineers at the University of Wisconsin-Madison in the US uses a car’s rolling tyre friction to generate electricity.

The technology, which is reported in the journal Nano Energy, could ultimately help automobile manufacturers a new way to squeeze greater efficiency out of their vehicles.

Thought to be the first of its kind the device relies on the triboelectric effect (electric charge that results from the contact or rubbing together of two dissimilar objects) to harness energy from the changing electric potential between the pavement and a vehicle’s wheels.

Xudong Wang an associate professor of materials science and engineering at UW-Madison, said that the technology offers a potential way of harvesting energy that is usually lost due to friction.

“The friction between the tyre and the ground consumes about 10 percent of a vehicle’s fuel,” he said “That energy is wasted. So if we can convert that energy, it could give us very good improvement in fuel efficiency.”

The nanogenerator relies on an electrode integrated into a segment of the tyre. When this part of the tyre surface comes into contact with the ground, the friction between those two surfaces ultimately produces an electrical charge.

During initial trials, Wang and his colleagues used a toy car with LED lights to demonstrate the concept. They attached an electrode to the wheels of the car, and as it rolled across the ground, the LED lights flashed on and off.