Breeze-Wind-Energy-Powered Autonomous Wireless Anemometer Based on Rolling Contact-Electrification

Abstract

A triboelectric nanogenerator (TENG) has great advantages in harvesting low-frequency mechanical energy, which is very suitable for energy harvesters and active sensors for breeze wind. Here, we report a breeze-wind-driven autonomous wireless anemometer (WWA) based on a planetary rolling triboelectric nanogenerator (PRTENG) for simultaneous wind energy harvesting and wind speed sensing. Benefitting from the planetary rolling friction, the PR-TENG can be activated at a wind speed of less than 2 m/s. At a wind speed of 5 m/s, the W-WA can be continuously powered and autonomously transmit wind speed data in the range of 10 m every 2 min. By integrating the TENG-based micro/nanoenergy harvester and active sensor, this work has realized a complete self-powered intelligent wireless sensing system, which has exhibited broad prospects in distributed micro/nanoenergy, unattended environmental monitoring, and the Internet of things. Wind as a kind of widely distributed and renewable energy has played a significant role in electric supply and contributed to alleviate the energy crisis. According to statistics, the exploitable part of global wind energy is up to 5.3 × 10 kWh per year. On the other hand, the anemometer is a powerful device for wind monitoring and weather forecasting that usually works in unattended environment and needs a long service life. Up to now, the anemometer is mainly supplied by short-term battery, which greatly increases the maintenance cost and environmental pollution. Therefore, harvesting wind energy from the ambient environment to power the anemometer is an optimal method to realize sustainable operation. As a new energy technology, the triboelectric nanogenerator (TENG) based on Maxwell’s displacement current was first proposed in 2012 and has been widely used as an energy harvester and active sensor. As an energy harvester, the TENG has a better output performance for harvesting lowfrequency and weak mechanical energy compared to a traditional electromagnetic generator, which can provide sustainable micro/nanopower sources for distributed electronic devices. As an active sensor, the TENG-based active sensor has the advantages of being lightweight, high flexibility, and an abundant selection of materials compared with the electromagneticor piezoelectric-based active sensor. Some TENG-based wind energy harvesters and sensors have been studied to harvest and monitor wind energy effectively. Although the TENG-based active wind sensor can directly convert wind information into sensing electrical signal without a power supply, the signal processing and transmission still need an external power supply for this kind of active sensor. If a TENG-based wind sensor can be supplied by a TENG-based power source, it is very promising to realize a fully self-powered system for autonomous wind