Because the trees can only produce about 200 mV of electricity, they cannot power large-scale lighting, heating, or industrial systems. But the trees can power small sensors- sensors that can save thousands of acres of forested land from deadly wildfires.
Wildfire detection is notoriously tricky. Traditional, battery-operated sensors are placed high on trees in remote wilderness. As the batteries need constant replacement, millions of dollars are spent on sensor network maintenance every year. Tree-powered sensors could eliminate most of that cost.
In addition, the tree sensors can collect real-time information on air, soil, and water conditions in remote areas. Ecological and environmental researchers usually travel to the locations that they study. The sensors would allow them to collect data from the safety of a lab. It's the difference between driving fifty miles on dirt tracks to collect a temperature reading and having that reading fed into your computer as you lounge in an armchair at home.
However, the new technology raises some important questions. Trees are a novel source of renewable energy, but they are also essential parts of forest ecosystems. If thousands of trees are "plugged in", will there be any effect on soil and water conditions? If trees are used to power remote sensors, how will animals be affected by the thousands of wires strewn across the forest?
Now, though, tree bioenergy converters (produced by VoltTree, a subsidiary of a major electronics manufacturer) are just being developed for fire sensors. According to Victoria Henderson, VoltTree's devices "truly have potential". If they work well, the power units could be used for nationwide infrastructure.
These generators are still in the early stages of development. Even in the nascent stages, though, they still represent an extraordinary leap in renewable energy research. Trees are no longer just landscaping features and sidewalk liners, but natural generators bristling, bubbling, and popping with energy.