Electricity from Trees Could Prevent Forest Fires
MIT researchers are designing a system that uses electricity from trees to recharge batteries and generate power in remote locations. The small amounts of tree-generated electricity could be used to track forest fires and possibly "patrol" borders for smuggled radioactive materials.
Although scientists have known for a long time that trees can produce small amounts of electricity, the MIT group recently discovered exactly how it works. As MIT's Shuguang Zhang, Andreas Mershin, and Christopher Love explained, trees generate electricity due to an imbalance in the pH of the tree and the soil it grows in.
Taking advantage of this understanding, the scientists plan to attach a bioenergy harvester battery charger module and sensors to about four trees per acre. The sensors can measure the temperature and humidity of the area, and the tree generates enough electricity for this data to be wirelessly transmitted back to a weather station four times a day, or immediately in the case of a fire.
The signals hop from one sensor to the next, until they reach a weather station. These remote weather stations all transmit the data by satellite to a forestry command center in Boise, Idaho.
By distributing more sensors throughout the forest - without the need to have workers go in and replace or recharge the batteries - researchers could find out about forest fires quicker, and then react more quickly.
The MIT scientists founded a company called Voltree Power to develop and test the wireless sensor network. They plan to begin tests next 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.