Photo: CalWave's xWave wave energy prototype (Courtesy of CalWave Power Technologies)

CalWave’s xWave prototype emerges as platform for various environmental monitoring ops

The recently deployed xWave wave energy prototype, developed by U.S.-based company CalWave Power Technologies, has served as a platform for several environmental research operations led by PNNL’s Triton initiative.

CalWave's xWave wave energy prototype (Courtesy of CalWave Power Technologies)
CalWave’s xWave wave energy prototype (Courtesy of CalWave Power Technologies)

In collaboration with CalWave, the Triton team has conducted two separate field trials around the xWave prototype device to test Integral Consulting’s NoiseSpotter technology and an underwater camera used to monitor changes in habitat around the wave energy converter’s anchors.

The xWave is a fully operational, submerged wave energy device – deployed in September 2021 in California – for a period of six months for performance testing, providing an opportunity for Triton to collect valuable empirical environmental monitoring data.

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The Triton is a Department of Energy (DOE) Water Power Technologies Office (WPTO) project, led by Pacific Northwest National Laboratory (PNNL), which studies environmental monitoring technologies and methods to understand the potential impacts associated with marine energy systems.

As part of Triton initiative, the NoiseSpotter technology was deployed on xWave demonstration site to characterize potential sound emissions from the wave energy device and other nearby sounds, such as marine mammal vocalizations.

The retrieval of the NoiseSpotter technology (Photo courtesy of Integral Consulting)
The retrieval of the NoiseSpotter technology (Photo courtesy of Integral Consulting)

The NoiseSpotter’s novel vector sensor array is said to enable researchers to gather information about the location and identity of those sounds in real-time.  

During these tests, multiple configurations of the NoiseSpotter were demonstrated, including real-time data collection with data transfer to the cloud, a drifting test to gather data decoupled from water currents, and self-logging data collection with no expression on the water’s surface.

The final demonstration was a huge success and brought the NoiseSpotter closer to the finish line of commercialization following successful development, testing, and validation of the technology at PNNL’s Marine and Coastal Research Laboratory.

Also, Triton’s ‘changes in habitat team’ travelled to xWave’s deployment location at University of California San Diego’s Scripps Institution of Oceanography (SIO) to deploy a Boxfish 360-degree underwater video camera around an anchor near the device.

The team deployed the camera at sunrise, midday, and around sunset to monitor habitats at different times of day, with and without underwater lights to illuminate the surrounding area.

The field tests assessed the utility of these cameras for monitoring artificial reef effects and other potential changes to habitats around marine energy devices and associated structures.

The deployment of the Boxfish camera (Photo by Cailene Gunn|Courtesy of PNNL)
The deployment of the Boxfish camera (Photo by Cailene Gunn|Courtesy of PNNL)

Data from this footage will inform a set of recommendations to decision makers in the marine energy industry on best practices for monitoring marine energy related changes to underwater habitats, according to Triton.

“Thank you to Dan Petcovic, Marcus Lehmann, and Thomas Boerner at CalWave for providing Triton with the opportunity to collect empirical data around a deployed WEC and real-time information about the WEC operating status.

“It was a memorable experience for all team members working around an operational WEC for the first time. The Triton team would also like to extend a huge thank you to the folks at SIO for helping make this research possible.

“From offering facilities and providing access to the Ellen Browning Scripps Memorial Pier, vessels, expertise, and a beautiful site to work, the team appreciates your support through the early mornings and long days conducting tests”, Triton said.

Soon, the Triton’s underwater noise team will be heading to SIO to deploy hydrophones around the xWave and characterize sound generated by the device.

This longer-term deployment of acoustic monitoring instruments, expected to last for several weeks,  will provide valuable data about the wave energy converter’s sound emissions, as well as information about the ambient acoustic environment, the researchers said.