Researchers at the University of California, Los Angeles (UCLA) have designed a new device that creates electricity from falling snow. The first of its kind, the device is inexpensive, small and as flexible as a sheet of plastic. The device can work in remote areas because it provides its own power and does not need batteries, said senior author Richard Kaner, professor of chemistry and biochemistry, and materials science and engineering at UCLA. Its a very clever device, a weather station that can tell you how much snow is falling, the direction the snow is falling, and the direction and speed of the wind. The researchers call it a snow-based triboelectric nanogenerator, or snow TENG. A triboelectric nanogenerator, which generates charge through static electricity, produces energy from the exchange of electrons. Static electricity occurs from the interaction of one material that captures electrons and another that gives up electrons. You separate the charges and create electricity out of essentially nothing, added Kaner. Snow is positively charged and gives up electrons while silicone is negatively charged. When falling snow touches the surface of silicone, it produces a charge that the device captures, creating electricity. Co-author Maher El-Kady, a UCLA assistant researcher of chemistry and biochemistry, added, Snow is already charged, so we thought, why not bring another material with the opposite charge and extract the charge to create electricity? While snow likes to give up electrons, the performance of the device depends on the efficiency of the other material at extracting these electrons. After testing a large number of materials including aluminum foils and Teflon, we found that silicone produces more charge than any other material. About 30% of the Earths surface is covered by snow each winter, during which time solar panels often fail to operate, El-Kady observed. The accumulation of snow reduces the amount of sunlight that reaches the solar array, limiting the panels power output and rendering them less effective. The new device could be integrated into solar panels to provide a continuous power supply when it snows, he said.
