Researchers at the Pacific Northwest National Laboratory (PNNL) harvest wave power using a gently rotating cylinder designed around the triboelectric effect that causes static shocks after walking on certain carpets. I have developed an unusual method.
The PNNL team has prototyped a new ‘Frequency-Multiplied Cylindrical Triboelectric Nanogenerator’ (FMC-TENG) specifically designed to extract power from low frequencies in the open ocean. We’re not talking megawatt-scale devices that can put energy back into the grid here. The team hopes these machines will be a practical, lightweight, low-cost way to power an open-sea surveillance platform that includes several sensors and a satellite communications system.
The triboelectric effect (prefix tribo for friction or friction) is not yet fully understood. We all know it exists because we’ve all reached for a door handle and given it a jolt. Also, much is known about which materials combine to produce the strongest electrostatic charge.
Current thinking is that it occurs when two different substances exchange electrons at the molecular level, creating an electrostatic attraction between them. When the two materials are rubbed together, these electrons are effectively separated before returning home, leaving behind an electrical charge, and the door handle will start watching you approach with malevolent glee.
FMC-TENG adopts a cylinder-in-a-cylinder design. The outside of the smaller cylinder and the inside of the larger cylinder are coated with artificial fur and a Teflon-like material called fluorinated ethylene propylene (FEP). The inner cylinder rotates freely and generates static electricity as it moves relative to the outer cylinder, which is collected by electrodes.
PNNL
TENGs like this have been built and used before, but to make this effective in slower, more uniform waves like those in the open sea, the PNNL team increased the movement between the two cylinders. I had to amplify the output by This was done by magnetically braking the movement of the inner cylinder, stopping it from spinning until it reached the crest of the wave. At this point, the maximum potential energy causes the magnet to release the cylinder and roll back much faster than normal. In this way, a single slow-moving wave can be converted into a multitude of faster rotations between the two cylinders, maximizing the triboelectric effect.
The end result is a more efficient TENG, able to generate more energy from slower wave motion. “FMC-TENG is unique because there are few wave energy converters that can generate significant power from efficient, low-frequency ocean waves,” said Daniel Deng, Fellow at PNNL Labs. energy. “This type of generator could potentially power integrated buoys with sensor arrays and track open ocean water, wind and climate data using entirely renewable ocean energy.”
This survey is available at: nano energy.
Source: PNNL
