Could our next big source of renewable energy come from thin air? Well, not exactly — but moist, dense air holds a great deal of promise.
While researching how water droplets interact with water-repellent or “hydrophobic” surfaces, engineers at the Massachusetts Institute of Technology (MIT) discovered that, in the right conditions, water droplets spontaneously leap into the air and repel each other, creating a small electrical current. Lead researcher Nenad Miljkovic, a postdoctoral associate at MIT’s NanoEngineering Group, says the discovery could lead to new ways to draw energy from the earth’s atmosphere.
The study, published in the journal Nature Communications, revealed that by placing two parallel metal plates across from one another, with one designed for the jumping droplets and the other created to catch them, it was possible to generate power from condensation in the air.
“You just need a cold surface in a moist environment,” Miljkovic says. The researchers are now working on a prototype to demonstrate this concept for future applications, and hope to have a working model in their laboratory next year.
The applications have a great deal of potential, but would be a supplemental form of power, as the output is relatively low compared to other forms of energy. However, in addition to the power generation this new discovery creates, understanding how it works could lead to the development of more efficient power plants and new methods of using available energy from the atmosphere.
See water droplets drawn to an electrically charged wire, which proves they carry an electric charge.