Scientists at Nanyang Technological University (NTU), Singapore have found an economical solution for clean energy. The team has developed a low-cost device that is sensitive enough to trap energy from a light breeze and turn it into electricity, generating enough to run a small commercial sensor.
The harvester is small, cheap, and measures around 15 x 20 cm (6 x 8 in). It has a cantilevered beam attached to a middle plate made of layers that capture energy through the triboelectric effect, in which different materials become electrically charged as they separate. This is caused by vibrations from the wind. This concept has already been applied to some wearable devices that generate energy from the wind as you walk.
The device is meant to be mounted on the exterior of buildings in urban environments. In their testing, the scientists demonstrated that it could create energy from a light breeze and can generate up to 290 microwatts of electricity. The device can also produce up to three volts and store electricity for use when there is no wind.
In one experiment, they used the device to power 40 LEDs consistently from a wind speed of four meters (13 ft) per second. In another, it was used to power a sensor that wirelessly relayed room temperature data to a mobile phone.
“As a renewable and clean energy source, wind power generation has attracted extensive research attention,” said Professor Yang Yaowen, who led the research. “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. The device we developed also serves as a potential alternative to smaller lithium-ion batteries, as our wind harvester is self-sufficient and would only require occasional maintenance, and does not use heavy metals, which if not disposed of properly, could cause environmental problems.”
The research was published in the journal Mechanical Systems and Signal Processing.