The recent forest fires in the United States, Australia, and Brazil have driven scientists at Michigan State University in East Lansing to design a fully self-powered forest fire detection and alarm system – the first of its kind.
The device is known as MC-TENG, which is short for multilayered cylindrical triboelectric nanogenerator. The MC-TENG hangs on a tree branch and generates electrical power by harvesting energy from the movement of the trees in the wind.
“As far as we know, this is the first demonstration of such a novel MC-TENG as a forest fire detection system,” says Changyong Cao, who directs the Laboratory of Soft Machines and Electronics and is an assistant professor in the School of Packaging and departments of mechanical engineering and electrical and computer engineering at MSU. “The self-powered sensing system could continuously monitor the fire and environmental conditions without requiring maintenance after deployment.”
Cao believes the MC-TENG will help emergency crews respond to forest fires more quickly, making the task of extinguishing wildfires easier and significantly reducing the damage caused by them.
Remote sensor technologies are less costly and more efficient than traditional forest fire detection methods, which include satellite monitoring, ground patrols and watch towers. Unlike other remote sensors, the MC-TENG does not rely on battery technology for power.
“Although solar cells have been widely used for portable electronics or self-powered systems, it is challenging to install these in a forest because of the shading or covering of lush foliage,” says Yaokun Pang, co-author and post-doctorate associate at Cao’s lab.
The MC-TENG converts the movement of tree branches into electricity via the triboelectic effect, the same phenomenon that causes static electricity.
The researchers selected TENG technology for its rapid charge and discharge times. This technology allows the device to adequately charge with only short, but sustained, gusts of wind.
“At a very low vibration frequency, the MC-TENG can efficiently generate electricity to charge the attached supercapacitor in less than three minutes,” Cao says.
The researchers outfitted the initial prototype with both carbon monoxide and temperature sensors to reduce the likelihood of a false positive carbon dioxide reading.
Cao hopes to field test a production device with materials that mimic a real fire. The team also aims to add additional functionality that allows the device to be adapted for the weather and environmental conditions where it is deployed.
The research was partially funded by the U.S. Department of Agriculture’s National Institute of Food and Agriculture, Michigan Economic Development Corp., American Society for Nondestructive Testing Faculty Grant Program, MSU, and MSU Technologies.