Triboelectric-Electromagnetic Hybrid Wind-Energy Harvester with a Low Startup Wind Speed in Urban Self-Powered Sensing

Abstract

Wind energy as a renewable energy source is easily available and widely distributed in cities. However, current wind-energy harvesters are inadequate at capturing energy from low-speed winds in urban areas, thereby limiting their application in distributed self-powered sensor networks. A triboelectric–electromagnetic hybrid harvester with a low startup wind speed (LSWS-TEH) is proposed that also provides output power within a wide range of wind speeds. An engineering-implementable propeller design method is developed to reduce the startup wind speed of the harvester. A mechanical analysis of the aerodynamics of the rotating propeller is performed, and optimal propeller parameter settings are found that greatly improved its aerodynamic torque. By combining the high-voltage output of the triboelectric nanogenerator under low-speed winds with the high-power output of the electromagnetic generator under high-speed winds, the harvester can maintain direct current output over a wide wind-speed range after rectification. Experiments show that the harvester activates at wind speeds as low as 1.2 m/s, powers a sensor with multiple integrated components in 1.7 m/s wind speeds, and drives a Bluetooth temperature and humidity sensor in 2.7 m/s wind speeds. The proposed small, effective, inexpensive hybrid energy harvester provides a promising way for self-powered requirements in smart city settings.

Advances in Triboelectric Nanogenerators for Sustainable and Renewable Energy: Working Mechanism, Tribo-Surface Structure, Energy Storage-Collection System, and Applications

“…Numerous research efforts have focused on utilizing TENGs for self-powered sensing applications. Examples include the development of a triboelectric nanogenerator for self-powered chemical sensors [251], the construction of a ring-shaped vibration TENG for vibration sensors [252], the creation of a sliding-mode TENG for self-powered security applications [253], the fabrication of a 3DWE-TENG for self-powered stretchable sensors, the construction of an SWF-TENG for self-powered stretchable sensing [254], the development of self-powered humidity sensors with structured surfaces (nanowire, nanoporous, nanotube, and monolayer) [255], the use of a garment-integrated TENG for pressure sensors [256], the construction of hybrid TENGs for self-powered sensors [257], self-powered humidity, and temperature sensors [258], the utilization of a flexible TENG based on MXene/GO composites for self-powered health monitoring [259], the construction of a C-TENG for self-powered strain sensors [260], and the production of a hybrid TENG and a piezoelectric nanogenerator for self-powered wear-able sensors [261]. Numerous surveys have highlighted the advantages of TENGs, such as their potential as a blue energy source [262], their role as a renewable energy resource [263], their green energy source suitability with sustainable diagnostics for human healthcare applications [244], their clean energy source attributes with small sizes [150], their ability to offer flexibility and smart applications through materials like MXene-TENG [264], their use as a self-powered device for biomechanical energy harvesting and behavior sensing [265], their suitability for portable and flexible wearable sensing and human healthcare applications [266], their ability to provide flexible and self-charging power systems [267], their capacity for stability and selectivity in self-powered and advanced chemical sensor systems [268], their capability to enhance the energy conversion efficiency for powering LEDs and various TENG applications [269], their proficiency as an effective power resource for flexible pressure sensing and portable electronic equipment [270], their competence in harvesting energy from low-frequency acoustic waves for capacitor charging [146], their ability to sensitively detect physiological signals…”

Investigation of a Novel Ultra-Low-Frequency Rotational Energy Harvester Based on a Double-Frequency Up-Conversion Mechanism

“…Therefore, there is an urgent need for a new type of power device that can provide a long-term energy supply. Energy harvesters, as emerging energy supply devices, leverage various mechanisms, such as piezoelectric [ 1 , 2 , 3 ], electromagnetic [ 4 , 5 ], triboelectric [ 6 , 7 ], and photovoltaic [ 8 , 9 ] effects, to convert mechanical energy, wind energy, solar energy, and other forms of ambient energy into electrical energy for external output. Among them, piezoelectric energy harvesters [ 10 , 11 , 12 ] have been employed in widespread applications due to their simple structure [ 13 , 14 ], long lifespan [ 15 , 16 ], and high adaptability [ 17 , 18 , 19 ] to environmental conditions.…”

Editorial for the Special Issue on Flexible and Wearable Sensors

“…In this Special Issue on Flexible and Wearable Sensors, we have included 25 papers, including 24 research papers, covering applications in human-computer interaction [ 1 , 2 , 3 ], mechanical design [ 4 , 5 , 6 , 7 , 8 ], health monitoring [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ], manufacturing technology [ 16 , 17 , 18 , 19 , 20 ], algorithms [ 21 , 22 , 23 ], and smart cities [ 24 ]. Additionally, we feature an intriguing review paper focusing on flexible wearable sensor devices for biomedical applications [ 25 ].…”

“…In particular, Xue et al proposed a frictional electromagnetic hybrid harvester with a low starting wind speed and an engineering-practical propeller design approach to achieve output power over a wide range of wind speeds [ 24 ]. Vanhala et al proposed a strategy for long carbon stitched fibers in the form of permeable carbon fiber cloth placed on a stretchable thermoplastic polyurethane matrix to improve the 3D printed matrix’s mechanical, electrical, and thermal properties [ 17 ].…”