Researchers Develop Novel Nanogenerator to Convert Wave Energy Into Electricity
Researchers at the Pacific Northwest National Laboratory recently developed a cylindrical powerhouse to transform low-frequency wave energy into a high-power electric output.
Researchers from Washington-based Pacific Northwest National Laboratory (PNNL) recently developed a novel cylindrical triboelectric nanogenerator (C-TENG) that converts wave energy into electricity for satellite communication systems, sensors in ocean observing platforms, and more applications.
This animation demonstrates the FMC-TENG’s wave energy harvesting mechanism in action. Gif used courtesy of Pacific Northwest National Laboratory
The researchers detailed their work in a recent study published in Nano Energy. Through the project, funded by the U.S. Department of Energy’s Water Power Technologies Office, the PNNL team envisioned an ocean energy harvesting solution that could generate power by converting low-amplitude, low-frequency waves into high-frequency mechanical motion. They developed a frequency-multiplied cylindrical triboelectric nanogenerator (FMC-TENG) equipped with magnets to store and release potential energy. Their FMC-TENG draws low-frequency wave energy to trigger a high-frequency swing motion, resulting in a high-power electrical output.
After testing the FMC-TENG against conventional designs and optimizing the mechanism in a 40-foot-long water tank, the researchers finally demonstrated that an array of FMC-TENGs could power an acoustic transmitter used in ocean observation systems (which are typically battery-powered).
Ocean Wave Energy Harvesting
Ocean energy converters are nothing new, having been developed mainly with electromagnetic generators. In their paper, the researchers cited the drawbacks of existing electromagnetic generators, which are often expensive and inefficient with low-frequency waves. Likewise, C-TENGs already exist for low-frequency wave energy harvesting, but waves’ low amplitude and frequency limit their operation and performance.
Daniel Deng, one of the paper’s authors and a fellow in PNNL’s Energy and Environment Directorate, stated that the patent-pending FMC-TENG differentiates itself in a market with few wave energy converters that are strong enough to generate significant power from low-frequency waves. One key application is ocean monitoring, where the FMC-TENG can power integrated buoys with sensor arrays that capture data in the open ocean.
Other teams have created similar devices to address various challenges in the wave energy harvesting field. For example, in 2021, Chinese researchers published a paper demonstrating how an active resonance TENG featuring a flexible ring could harvest omnidirectional wind energy, bypassing the random direction and frequency typical of ocean waves.
Video used courtesy of Pacific Northwest National Laboratory
Featured image used courtesy of Adobe Stock