A team of Chinese engineers has developed a thermoelectric generator capable of converting waste heat into electricity without using any moving parts. In other words, this means that the generator is quiet, robust and will hardly require maintenance or replacement of parts for wear.
The creators’ goal is for the machine to be used to produce electricity from solar radiation, the residual heat from industrial machines, equipment and boilers, the combustion of biomass and geothermal energy.
“This generator also promises a theoretically high efficiency of converting heat to electricity. And we designed and built a conceptual prototype to validate the viability of our concept. In preliminary experiments, we reached 15 volts at the highest voltage amplitude in open circuit, which it implies that our concept has been well demonstrated, “said Professor Guoyao Yu, from the Technical Institute of Physics and Chemistry, in China.
How does the generator work?
The creation consists of two parts: a thermoacoustic motor, which transforms heat into vibrations, and a triboelectric generator made of liquid metal, which uses these vibrations to produce electricity. The whole process begins when the thermoacoustic engine converts thermal energy into acoustic energy through oscillatory thermal expansion and the contraction of a gas.
The next step is the conversion of this acoustic energy into electrical energy through the coupling effect of electrostatic induction and contact electrification. When the first part, that is, the thermoacoustic engine, receives the energy, the gas inside it starts a spontaneous oscillation.
“The oscillatory movement of the gas pushes a column of liquid metal [causing it] to flow back and forth into a U-shaped tube. This causes the liquid metal to periodically dip and separate from a poly film. imitate, generating alternating voltage at the electrodes. This draws electricity from the triboelectric generator, “explained Yu.
Expectations for creation
Among the expectations for the generator, the team intends to develop miniature versions, that is, nanogenerators. The goal is for these small “machines” to be used in vehicles, in microelectromechanical systems and even in space applications.