Nanyang Technological University, Singapore (NTU Singapore) researchers have created a low-cost gadget that can capture and store energy from wind as soft as a light breeze. Tagged as the wind harvester, the lightweight and robust device also redirects any unused electricity to a battery, where it can be stored to power equipment in the absence of wind.
When exposed to winds as low as two metres per second (m/s), the device may create a voltage of three volts and electrical power of up to 290 microwatts, which is enough to operate a commercial sensor device and transfer data to a mobile phone or computer.
“As a renewable and clean energy source, wind power generation has attracted extensive research attention. Our research aims to tackle the lack of a small-scale energy harvester for more targeted functions, such as to power smaller sensors and electronic devices,” says Professor Yang Yaowen, a structural engineer from NTU’s School of Civil and Environmental Engineering (CEE).
Professor Yang, who also led the project, stated that the wind harvester is a potential alternative to smaller lithium-ion batteries because it is self-sufficient, requires only occasional maintenance, and does not contain heavy metals that, if improperly disposed of, could cause environmental issues.
According to the researchers, their technology has the potential to replace batteries in light-emitting diode (LED) lighting and structural health monitoring devices. These are used on urban structures like bridges and skyscrapers to monitor structural health and warn engineers of problems like instabilities or physical damage.
The gadget, measuring only 15 centimetres by 20 centimetres, is simply mountable on the sides of buildings and would be suitable for urban locations, such as the suburbs of Singapore, where typical wind speeds are less than 2.5 m/s outside of storms.
The industry has shown interest in the idea. Additionally, the NTU research team is seeking to commercialise their discovery. The study, which presents an innovation that could aid in the reduction of electronic waste and the discovery of alternative energy sources, demonstrates NTU’s commitment to reducing the environmental impact, one of four grand challenges that the University seeks to address through its NTU 2025 strategic plan.
The gadget was created to efficiently harness wind energy at a cheap cost and with minimal wear and tear. The main attachment that interacts with the wind is made of inexpensive materials, including copper, aluminium foil, and polytetrafluoroethylene, popularly known as Teflon, an extremely durable polymer.
When the harvester is exposed to wind flow, its dynamic construction causes it to vibrate, forcing the plate to approach and leave the stopper. This causes charges to build on the film, which flows from the aluminium foil to the copper film to generate an electrical current.
In laboratory tests, the NTU-developed harvester consistently powered forty LEDs at a wind speed of four metres per second. It could also activate a sensor device and provide sufficient power for it to wirelessly transmit room temperature data to a mobile phone.
This demonstrated that the harvester could not only generate enough electricity to regularly power a device but also store sufficient excess charge to keep the gadget powered for a lengthy period when there was no wind.
The NTU team will undertake additional research and experiment with other materials to improve the output power and energy storage capabilities of their gadget. Additionally, the research team is in the process of filing a patent application with NTUitive, the university’s innovation and entrepreneurship organisation.
