CorPower Ocean is working in collaboration with WavEC Offshore Renewables to deliver an extensive Environmental Monitoring Program to verify the environmental impact of its wave energy technology.
Phase one involving underwater noise baseline campaigns has been concluded at the HiWave-5 Wave Energy Park, off the coast of Aguçadoura, in northern Portugal. The work involved analysis of ambient noise in the project area prior to installation.
Two campaigns were carried out during January and May 2022, to record noise during two different seasons of the year. Acoustic data was collected using three autonomous hydrophones installed 20m from the seabed.
Results will be used as benchmark against underwater noise levels during the C4 operation.
WavEC Marine Environmental Researcher and Project Manager, Inês Machado, said: "During this initial campaign we recorded natural sources of noise including the action of wind on the surface, breaking waves, water flow, rain, sediment movement and the presence of marine fauna. In addition, we recorded anthropogenic noise sources such as maritime traffic, largely related to fishing activity, which is the biggest contributor to noise in the area. The results reveal that the SPL (Sound Pressure Level) was similar between the January and May campaigns. However, it was possible to conclude that the predominant sources contributing to ambient noise levels at lower frequencies up to 1kHz was maritime traffic at distance. On the other hand, the contribution of marine traffic to ambient noise levels was lower in January, where cetacean vocalizations were more predominant sources of ambient noise."
The HiWave-5 Project will ultimately consist of four wave energy converters, with a combined 1.2 MW power rating, fixed to the seabed through a system of perforating anchors. Its installation is divided into two stages, beginning with the demonstration and certification of a full-scale 300 kW C4 prototype later this year. The second phase will involve the demonstration and certification of a set of three C5 devices.
Enric Villarin, project manager in CorPower Ocean said: "We now have solid data regarding current noise levels at the Aguçadoura test site. Using these benchmarks, we will be able to conduct a thorough assessment of the project's contribution to ambient noise during different operating states and seasons. We look forward to the next stage of the underwater noise monitoring campaign during the operational phase of the HiWave-5 Project, helping prove the low environmental impact of wave energy technology."