A new forest deployed fire sensor has been developed and is powered by the swaying of tree branches.
Older tree mounted fire sensors were powered by batteries. That meant that fire workers would periodically have to walk into the woods and replace the batteries. Solar panels were also used but dense forests tend to be shaded by foliage making the panels not ideal.
Looking for a better solution scientists at Michigan State University look into the triboelectric effect. To put it simply this phenomenon generates an electrical charge when one material is separated from another material that was in contact with. This is responsible for the static charge that is generated when you come your hair.
The Michigan State device is called the MC-TENG, which stands for multilayered cylindrical triboelectric nanogenerator.
In its simplest form, it incorporates two cylindrical sleeves of different materials, one nested inside of the other. While one of these is anchored solidly in place, the other is attached to the branch of a tree. As that branch sways back and forth in the wind, it pulls the cylinder with it, sliding it in and out of contact with the anchored cylinder. This generates a triboelectric charge, which is stored in a carbon-nanotube-based micro supercapacitor.
In order to increase the electrical output, a more advanced version of the device utilizes multiple cylinders layered one inside the other – hence it being called “multilayered.” As a result, even short (but frequent) gusts of wind over a period of three minutes provide enough power to run integrated carbon monoxide and temperature sensors.
It is hoped that a final, weatherproof version of the MC-TENG will be able to not only detect fires, but then proceed to wirelessly transmit alerts to firefighting stations.
Source: Michigan State University