CorPower Ocean and Maersk Supply Service have installed a subsea export cable off the coast of northern Portugal to energize the HiWave-5 wave energy project.
The 6.2 kilometer-long and 100 tonne-heavy cable was installed using the Maersk Achiever vessel and will provide power and data connection from an on-land substation in Aguçadoura to the wave energy demonstration site , located 5.5 kilometers offshore.
Now connected to the national grid of Portugal, the site will initially accommodate the recently unveiled CorPower Ocean ’s C4 wave energy converter , which will later form part of a larger four-system array, and one of the world’s first grid-connected wave farms.
CorPower Ocean’s marine operations manager, Robert Argo , said the cable lay process marks another significant milestone for the HiWave-5 project , which aims to introduce certified and warrantied wave energy converter products to the market.
“We started the installation process by positioning the Maersk Achiever in a safe water depth within the cable corridor, approximately one kilometer offshore. A messenger line was passed from an onshore winch to the Maersk Achiever, and then connected to a cable pull-in head.
“As the cable was being deployed buoyancy was attached to assist with the cable float into shore. Once onshore the cable was pulled through a pre-installed cable conduit running under the beach and into the on-land substation, while the remaining cable was deployed using an onboard cable tensioner,” said Argo.
He noted that during the lay operation, cable protection was added to provide additional mass where required for on-bottom stability.
Various parameters were also monitored throughout including cable tension, cable departure angle and touch down monitoring, and on completion, a visual and positioning survey was carried out by a remotely operated vehicle .
“The cable lay process is a notoriously challenging aspect for marine energy projects, with much planning required and adaption to weather windows and ocean conditions.
“ We are thankful to our highly diligent and professional partners, including Maersk Supply Service for their close support throughout the entire operation,” Argo concluded.
The C4 power take-off (PTO) system , which has completed a one-year dry test program in Stockholm, will be integrated with the device’s composite hull , custom built at CorPower Ocean’s Portuguese base, in Viana do Castelo.
Having successfully completed tests to verify power conductors and fiber communication cores, the CorPower C4 wave energy converter will later be fused to the cable through a quick-connect interface located at the anchor-head, the company said.
While providing power connection to feed electricity to shore through the 7.2kV cable it will also deliver high speed communication to the wave farm through fiber optic cores.