Novel Energy-Harvesting Nanogenerator Inspired By Seaweed

Nov, 2021 - By SMI

Scientists utilize seaweed motion in an underwater energy-harvesting device to convert ocean waves into electricity.

Ocean waves have been used for generating renewable energy for a very long time. These waves can be powerful, as they contain enough power to push around pebbles, sand, and even boulders. Such waves and smaller, gentler waves can be trapped to use as a source of renewable energy. A team of scientists at Dalian Maritime University found a way to use motion of seaweed in an underwater energy harvesting device to efficiently convert these surface and underwater waves into electricity to power marine-based devices.

Inspired by seaweed, the new device is a triboelectric nanogenerator known as TENG, which uses accumulation of electric charge in one material when it is separated from another material that it was in contact with, which is known as triboelectric effect. The scientists used a thin layer of porous sponge material sandwiched between strips of two polymers with size of 1.5x3 inch. The strips are coated using a conductive ink and the sponge creates air gap between them. The whole device is then seal packed with waterproof tape.

When the TENG device is put under a weak water current, it bends back and forth and the two strips of polymers get squeezed through the sponge and come in and out of contact with each other intermittently producing an electric current during the process.When the scientists tested the TENG in a tank, they found that the air gap between the two strips narrows. However, the device still produces current at a pressure of 100 kPa. Moreover, the team also discovered that using multiple triboelectric nanogenerators could power marine-based devices reducing the need of battery changing process.