Rolling wave generators could power the ‘ocean of things’

Researchers are working to create a nanogenerator that harnesses the energy of the ocean to power sensors

Spotted: Maritime weather, including extreme events like tsunamis and hurricanes, is monitored using sensors in the sea, and this data is critical for protecting coastal communities. While they are crucial devices, they are also battery-powered, meaning they must be periodically replaced. Now, researchers from the Pacific Northwest National Laboratory (PNNL) are working on an ocean sensor that can be powered by the energy in ocean waves, meaning the sensor could be powered indefinitely.  

The scientists are developing a new cylindrical triboelectric nanogenerator (TENG) that converts wave energy into electricity to power devices at sea. The faster the waves, the more a TENG moves, generating more static electricity that can be converted into power.

To generate enough power from the slower waves of the open ocean, the team found that the key was temporarily stopping the device’s inner cylinder from moving using magnets. This prevents the inner cylinder from rotating until it reaches the wave’s crest, allowing it to build up more potential energy. Then, once near the crest, the magnets release and the internal cylinder rolls down the wave very quickly. This faster movement produces electricity more efficiently, generating more energy. 

The prototype has produced enough electricity to power an acoustic transmitter, which is about the same amount of electricity it takes to power an LED lightbulb. The FMC-TENG is also lightweight and can be used in both free-floating devices and moored platforms. Larger versions of this generator could also be used to power ocean observation and maritime communications systems. 

Springwise has spotted other innovations making use of wave power, including a cheap floating converter, and a wave-powered desalination technology.

Written By: Anam Alam