Everyone knows that trees combat climate change by absorbing carbon dioxide out of the air. Now, plant leaves are tackling global warming in another way — by serving as models for a technology that produces clean, renewable power. UC Berkeley researcher Michel Maharbiz, has worked with other scientists to develop an alternative energy system based on transpiration, a natural process where trees pull water from roots to tops, with liquid eventually evaporating off of the leaves. The system relies on artificial glass leaves to generate a steady stream of energy and is yet another example of biomimicry at work.
An early version of a transpiration actuation system developed by the Maharbiz Group was inspired by fern spore-release structures
The synthetic leaves are essentially energy scavengers, deriving power from the evaporation-driven flow of water. Leaves are crafted from glass wafers containing a series of tiny, water-filled channels. Fluid flows through the channels until it reaches the edge of the leaf, where it then evaporates. The actual power production takes place in the leaf’s central stem walls, which are lined with metal plates connected to a circuit. The charged metal plates separated by a layer of water essentially create a capacitor. Water flowing through the leaf is periodically interrupted by small air bubbles–because air and water each have different electrical properties, every time an air bubble passes through the plates, an electric current is generated. This electricity can then be harvested and used to power devices, homes or other energy-sucking items.
Though the electricity produced is a relatively small amount when compared to power produced by fuel cells and batteries, Maharbiz asserts that the glass leaves are actually quite effective for this type of energy-scavenging system. Researchers are currently working on modifications to optimize the amount of power the leaves can produce.
Eventually, leaves could be implemented into whole artificial trees. Maharbiz envisions the trees acting as a complementary tech to solar, where sunlight could power panels and help drive transpiration in trees. With any luck, solar panels and artificial, power-producing trees will soon be as common to the American home as white, picket fences.
Via New Scientist
Lead photo by Dylan Parker