Developed by a European consortium of experts led by CorPower Ocean, the UMACK technology provides a step-change improvement to the vertical holding capacity of pile-type anchors. It offers significant reductions to cost and carbon footprints compared to both monopiles and gravity foundations and can support offshore installations such as marine energy devices, floating wind and aquaculture.
CorPower Ocean Senior Engineer Ian Denton said the UMACK anchor design and installation plan was tailored for the C4 Wave Energy Converter and specific requirements of the Aguçadoura site.
"The UMACK anchor has now been installed in northern Portugal," he said. "We installed the pile using a 500MU vibro-hammer supplied by Dieseko, supported by a heave-compensated crane on the Maersk Achiever vessel. The installation method works by vibrating the anchor into the sea bed, offering a high speed, low-noise solution which minimises impact on the marine environment. The success of the project hinged on careful planning and close collaboration with partners from Dieseko and Maersk Supply Service, in addition to nearly four years developing and scale-testing the innovative UMACK anchor technology. The outcome demonstrates the readiness of deploying this anchor at industrial scale."
The UMACK anchor is structurally efficient, this specific version being 1.6metres in diameter, 24meters long and 43tonnes in weight, with an ultimate tensile capacity in excess of 15MN. By comparison, a conventional monopile with the same capacity would be circa 4.5metres in diameter, 22metres long and 153tonnes in weight. A gravity anchor with the same capacity would have a mass approaching 1500tonnes.
The innovative technology includes a pile tip design which exhibits reduced soil resistance during vibro-installation, enabling the anchor to be driven to the desired penetration depth. Once the vibration stops, the UMACK anchor mobilises a large volume of soil which enables it to generate significant tensile capacity. Durable enough to resist more than 100million load cycles, the UMACK anchor is suitable for sea beds of sand and clay mixes.
"Pile anchors, as used for the UMACK installation, are likely to be one of the main anchoring systems used for marine energy devices, in particular in mooring systems for commercial floating wind farms. This innovative technology brings significant added value such as cost reduction. We are looking forward to continuing to support such innovations and to working with Corpower Ocean on future developments," said Jonas Munch Agerskov, Chief Commercial Officer at Maersk Supply Service.
Dieseko Group CEO Dirk Smulders said: "Dieseko strives to accelerate the energy transition with smart innovative foundation solutions, that are ecological friendly and enhance a fast and efficient installation process. The collaboration with CorPower to create a fast and reliable installation method, was experienced as very constructive, thorough and energetic. We are looking forward to further support Corpower in developing wave energy as an effective alternative for sustainable energy production."
The Aguçadoura site will initially accommodate a single CorPower C4 WEC device, which later form part of a larger four-system array, and one of the world's first grid-connected wave farms. The HiWave-5 Project ultimately aims to introduce certified and warrantied WEC products to the market.
The Hiwave-5 project is funded by the Swedish Energy Agency and Portugal 2020 through AICEP Global and CCDR-N.