Driving-torque self-adjusted triboelectric nanogenerator for effective harvesting of random wind energy

Triboelectric nanogenerators (TENGs), as a new energy technology for distributed power, are used widely in the field of the natural environment energy harvesting. Because the natural energy is random and unstable, dynamic matching between TENGs driving-torque and natural environment energy is fundamental for improving the applications of TENGs. Therefore, a driving-torque self-adjusted triboelectric nanogenerator (SA-TENG) for effective harvesting of random wind energy is developed in this paper. When the external wind speed is unstable, the SA-TENG automatically self-adjusted its driving-torque to dynamically match the wind speed and obtain higher output power. Experiments showed that the SA-TENG can adjust its driving-torque in accordance to the wind speed ranging in 5.0-13.2 m/s, and that, the output peak power can reach 7.69 mW. Under the same conditions, in comparison with a normal TENG, the power growth rate and the highest energy conversion ef-ficiency of the SA-TENG were boosted by more than 4.3 and 12.2 times, respectively; values that are also 3.2 and 6.5 times higher, respectively, than those of an electromagnetic generator. Additionally, the SA-TENG can supply power to sensors for monitoring environment, proving its feasibility as a distributed energy source.