Inexpensive device that can harvest energy from a light breeze and store it as electricity

Researchers from Nanyang Technological University in Singapore (NTU Singapore) have created a low-cost tool that can capture power from wind energy as moderate as a light breeze.

The gadget can create a voltage of three volts and energy power of up to 290 microwatts when exposed to winds with speeds as low as 2 meters per second (m/s). This is enough to power a commercial sensor device and allow it to transfer data to a smartphone or computer.

The portable, sturdy appliance, known as a wind harvester, also directs any unused electricity to a battery so that it may be stored and used to power gadgets when there is no wind.

The researchers claim that their creation has the potential to take the place of batteries in the powering of sensors for structural health monitoring and light emitting diode (LED) lighting. These are used to monitor the structural health of metropolitan constructions like skyscrapers and bridges, warning engineers of problems like instabilities or physical damage.

The gadget, which is about 15 by 20 centimeters in size and is simply mountable on building sides, is perfect for urban settings like Singaporean suburbia where, outside of thunderstorms, typical wind speeds are less than 2.5 m/s.

In September, the results were published in the journal Mechanical Systems and Signal Processing.

The project's director, Professor Yang Yaowen, a structural engineer from NTU's School of Civil and Environmental Engineering (CEE), noted that research has focused heavily on wind power generation as a clean and sustainable energy source. Our study intends to address the dearth of a small-scale energy harvester for more specialized uses, such as to power more compact electrical and sensor equipment.

As our wind harvester is self-sufficient, would only need infrequent maintenance, and does not use heavy metals, which, if not disposed of correctly, might create environmental concerns, it also serves as a potential substitute for smaller lithium-ion batteries.

The industry has expressed interest in the idea. The NTU research team is also attempting to market their creation.

The study demonstrates NTU's dedication to reducing our impact on the environment, one of four grand challenges facing humanity that the University seeks to address through its NTU 2025 strategic plan. The innovation presented in the study could help reduce electronic waste and find alternative energy sources.

Taking to the wind

The system was created to efficiently capture wind energy at a cheap cost and with little wear and tear. The main attachment that interacts with the wind is constructed of affordable materials like copper, aluminum foil, and polytetrafluoroethylene, commonly known as Teflon, and is attached to the body, which is made of fiber epoxy, a highly durable polymer.

The harvester vibrates when exposed to wind flow because of the dynamic nature of its structure, forcing its plate to move toward and away from the stopper. When a result, charges develop on the film, and as they move from the aluminum foil to the copper film, they create an electrical current.

In laboratory experiments, the NTU-developed harvester was able to reliably drive 40 LEDs at a 4 m/s wind speed. Additionally, it may activate a sensor device and provide enough power for it to wirelessly transmit data about the room's temperature to a smartphone.

This showed that the harvester could not only reliably produce electricity to power a device but also store surplus charge to maintain the gadget's power for a lengthy period of time without wind.

Prof. Yang said, "Wind energy is a renewable energy source. It does not pollute, it cannot run out, and it lessens the need for fossil fuels, which are where greenhouse gasses that contribute to global warming are produced. Our idea has shown to successfully capture this renewable source of energy to run LEDs and charge batteries, indicating its promise as an energy generator for the next generation of electronics, which will be more compact and power-efficient.

The NTU team will carry out more research to enhance the device's energy storage capabilities as well as undertake material experiments to increase its output power. The study team is also submitting a patent application to NTUitive, the university's innovation and entrepreneurship organization.