MIT researchers say trees may be able to power a network of sensors to prevent spreading forest fires.
The sensors could save trees by providing better local climate data to be used in fire prediction models. But manually recharging or replacing batteries at hard-to-reach locations is impractical. The new sensor system seeks to avoid this problem by tapping into trees as a self-sustaining power supply.
Each sensor is equipped with an off-the-shelf battery that can be slowly recharged using electricity generated by the tree. A single tree doesn’t generate a lot of power, but over time the “trickle charge” adds up, “just like a dripping faucet can fill a bucket over time,” said Shuguang Zhang, one of the researchers on the project and the associate director of MIT’s Center for Biomedical Engineering (CBE).
The “Early Wildfire Alert Network” (EWAN) consists of thousands of tiny humidity and temperature sensor nodes distributed over remote forestland. They connect to some 2,200 interagency Remote Automated Weather Stations (RAWS) located throughout the United States.
Each signal hops from one sensor to another, using the ZigBee standard, until it reaches an existing weather station, which stores the remote sensor data. That is combined with the station’s own data on Peak winds, Air temperature, Fuel temperature, Fuel moisture, Relative humidity, Solar radiation, and Warnings, then transmits it on the GOES weather satellite data channel, every hour, three hours, or immediately if there’s a fire.
The data is received by the National Interagency Fire Center in Boise, Idaho.
Testing of the wireless sensor network, which is being developed by Voltree Power, is slated to begin in the spring on a 10-acre plot of land provided by the Forest Service. The original experiments were funded by MagCap Engineering, LLC, through MIT’s Undergraduate Research Opportunities Program.
