Researchers from the China University of Hong Kong (CUHK) have proposed an interesting modular design for small-sized generators of electrical power. The development makes it possible to generate electricity from many types of movement in nature, in transport or during the movement of a person himself, and in the collection of wave energy, the new technology is capable of revolutionizing.

Image source: Chinese University of Hong Kong

Nanogenerators proposed by scientists from China rely on the collection of energy in the process of friction – this is the so-called triboelectric effect. Until now, generators based on this effect have been systems with rubbing external parts. This made it possible to generate a sufficiently large power, but led to wear of the friction surfaces. Scientists at CUHK have found an interesting alternative to this.

Image source: Chinese University of Hong Kong

The Chinese-proposed WT-TENG (Water Tube Triboelectric Nanogenerator) is a small, sealed vessel the size of an index finger with embedded electrodes and half filled with deionized water. Such water has a very high resistivity, since it is purified from impurity ions.

Image source: Chinese University of Hong Kong

The translational, oscillatory and rotational motions force the water to move in the vessel between the areas of the two electrodes and acquire a charge (electrify) due to friction with the electrode material. The electrodes are also electrified from this and acquire the opposite charge, which creates a current between the electrodes and this can last for a very, very long time.

Rafts of these lightweight and surface-connected generators can replace heavy, bulky, and maintenance-intensive modern wave power generators.

Nanogenerators WT-TENG produce a flux with a density of nine milliculons per meter³ at frequencies up to 0,25 Hz. This is very small for a single power source, but a battery from such devices can power relatively demanding devices. For example, scientists have shown how several generators on a runner’s wrist lit a panel of 150 LEDs, or the same panel would light up when a container with generators was rocked on a sea wave. For the world with renewable energy, this is a very interesting and promising development.