Floating offshore wind technology is powering forward. The UK government is among those looking for the deployment of wind farms in deeper waters to play a part in its green electricity drive.
It is targeting 5GW of electricity generation from floating offshore wind by 2030, as part of its broader ambition to reach 50GW of total offshore wind capacity by that year.
Delivering the right sealing solutions for deep-water floating wind farms, which have to withstand extreme weather conditions, including high winds and waves, as well as the corrosive marine environment, is vital.
Roxtec, long-established as a leading sealing solution provider for offshore wind, is playing its part in the development of the floating technology, working in close partnership with companies leading the field.
Global frontrunners are already generating electricity. The 25 MW WindFloat Atlantic project, the world’s first semi-submersible floating offshore wind farm, off the coast of Viana do Castelo in Portugal, celebrated five successful years of operation earlier this year.
Electricity production has steadily increased each year, reaching 86 GWh in 2024, and it stands as a model for the future of commercial scale floating offshore wind energy.
Principle Power, a global leader in the technology, specified Roxtec sealing solutions for the foundation that it designed for the project.
Those solutions were needed to cover low-voltage, high-voltage, and fibre optic cables; cables in multicore or trefoil formation and cables with varying bending radius and thickness, entering columns or passing through steel bulkheads.
The collaborative work of Roxtec and Principle Power led to a standardised solution flexible enough to meet the individual needs of each cable within the same penetration.
The work provided Principle Power with a library of options ready for deployment. It also used the Roxtec Transit Designer software to specify the various seals, considering the cable properties and required protection for each penetration.
The software allows hundreds of cable and pipe transits to be ‘designed in’ to a project in just a few minutes, simplifying product selection as well as the entire process that surrounds cable and pipe transits.
Seth Price, Vice President of Technology and Innovation for Principle Power, said: “Roxtec is among the internationally recognised sealing specialists, with track-record and experience in the oil and gas industry that can be adapted to the floating wind sector.
“We have been laser-focused on every detail of our technology to ensure quality, fabrication efficiency, and reliability. Applying standardised solutions that are readily available in the industry, like Roxtec seals, has proven to be successful.”
He added: “This type of solution will be instrumental for upcoming projects as we optimise technology for commercial scale and aim to deliver reliable cost-competitive solutions to project developers.”
Spanish headquartered Saitec Offshore Technologies also specified Roxtec cable seals for its innovative SATH floating wind turbine concept – a unique floating platform for offshore wind turbines suitable for shallow and deep waters.
A fully watertight sealing solution for the offshore environment was required. Seals for partitions and cabinets also had to be openable and removable in case more cables or ducts had to be installed.
Roxtec’s proven offshore performance and customised solutions proved invaluable to the development project. Its round seals and rectangular and compact cable and pipe transits were used to seal off cable ducts for low-voltage and medium-voltage cables, as well as closing off refrigeration ducts from the exterior offshore environment.
Seals of different sizes were used for marine type power cables and pipes. Roxtec also created a customised sealing module to help Saitec seal flat cables.
Aitor Sanz, Offshore Wind MEP Manager at Saitec Offshore Technologies, said: “We need offshore environment protection of the internal equipment and cabinets of the wind turbine generator at the transition piece and other areas of the floating platform.
“We developed an excellent collaboration with the Roxtec team and we believe that their watertight solution will have a great performance in harsh offshore conditions.”
Rob Cullen, Decarbonisation Technical Manager at Roxtec UK and Ireland, says the projects highlight how the business is well positioned to deliver solutions that work for floating offshore wind energy projects as the drive towards commercialisation quickens.
He says: “Since 2002, Roxtec has been a leading global supplier to the wind power generation industry, participating in over 130 large-scale projects. Today our cable and pipe sealing solutions can be found in more than 90 percent of wind farms worldwide.
“It is that level of expertise and technical know-how, coupled with our partnership approach, that will be vital for companies as they work to deliver floating offshore wind farms in harsh conditions.”
Roxtec was founded in Sweden in 1990. It is now the global leader in the manufacture of innovative cable and pipe transit systems. It is active in more than 80 markets with a turnover of more than £271million (US$364m) employing over 1000 staff across 28 sales companies.
Roxtec’s products are designed to seal cables and pipes, and are used to protect people, buildings and equipment from multiple hazards.