Dynamic cables for a dynamic offshore market

Wind turbines are learning to swim. In the future, they will be installed far off the coasts, in harsh environments and in deep oceans.  These floating offshore wind turbines will increasingly be used to take advantage of the strong and consistent winds, contributing to the energy transition. The enablers of this development? New dynamic high-voltage cables.

Offshore wind energy is already riding the wave – “it is set to grow worldwide, having recorded the second-highest number of new installations in 2023,” explains the Global Wind Energy Council (GWEC). In 2023, the wind industry installed 10.8 GW of new offshore wind capacity, bringing the total global capacity to 75.2 GW. The amount of new capacity added was 24 percent higher compared to the previous year. 

Offshore market for the energy transition
The GWEC projects that this growth rate will continue until 2030, if the political momentum lasts. The GWEC expects Australia, Japan, South Korea, the Philippines, Vietnam, Brazil, Colombia, Ireland and Poland to be the next markets for offshore wind expansion. According to the GWEC, 410 GW of new offshore wind capacity will be installed over the next decade. This rapid expansion must be based, among other things, on increased cooperation between industry and government. And manufacturers of cable machines and cables are happy to make their contribution to this.

Huge offshore potential of the deep sea
An important piece of the puzzle for the offshore success story lies in harnessing the strong winds far from the coasts. Conventional offshore wind farms have so far been unable to take advantage of these inhospitable areas far from dry land, where the ocean is more than 60 metres deep, and which account for 80 percent of the total sea area. This is unfortunate because, as the cable system manufacturer Nexans explains, “stronger and more consistent wind speeds translate to a more reliable source of energy”.

The aim is to exploit the enormous potential of the deep sea in the future. Floating offshore wind turbines are now seen as a beacon of hope for sustainable energy supply, as highlighted by the German Federal Ministry of Education and Research, for example. Unlike conventional turbines, which are firmly anchored to the seabed, floating systems are more flexibly tethered to the seabed with mooring lines.

Dynamic cables for floating offshore installations
Cable system manufacturers such as Nexans have also long been focusing on wind power in the deep sea. “From 2031, floating wind turbines will account for more than ten percent of annual offshore wind installations, a remarkable achievement given the rapid expansion of offshore wind energy as a whole,” the company explains. Cables, which are needed to transport the energy back to the shore, are “a crucial link for the future of floating wind power". This demands robust, dynamic high-voltage cables that capable of withstanding the harsh conditions at sea: A dynamic cable moves in the water and on the seabed, following the rhythm of the floating wind turbine.

In 2021, Nexans achieved “an important breakthrough” with the qualification of the first dynamic 145 kV cable for water depths of 1,300 metres. This cable was selected for the Jansz-lo project, located about 200 kilometres off the coast of northwest Australia, and considered a “pioneer in floating offshore wind projects,” according to Nexans. The company is responsible for manufacturing and installing the 140-kilometre submarine cable.

Offshore boom drives surge in orders
The offshore sector is booming: wind turbine manufacturers and suppliers, including the cable industry, are securing an increasing volume of orders. For example, Vattenfall: the company has signed a contract with Vestas for 112 latest-generation offshore wind turbines, each with a capacity of 15 MW. These turbines will be deployed in the Northern Lights 1 and 2 offshore wind projects in the German North Sea off the island of Borkum, jointly owned by Vattenfall and BASF. From 2028, they will be capable of producing electricity for the equivalent of 1.6 million households. According to Vattenfall, some of the tower elements will be made of low-emission steel, significantly reducing the CO₂ footprint of the towers.

Nordex has also received an order from Canada to supply a wind farm developer and operator with 19 of its N163/5.X turbines for a project in the province of Quebec. The turbines, to be installed on 125-metre-high tubular steel towers are scheduled for delivery in the summer of 2026. The company has also secured orders from Canada for 74 of its N163 turbines for a total capacity of 500 MW, to be delivered between 2025 and 2026.

Resilient cables are essential
The surge in new projects also means a large number of orders for components from the cable industry. Cables are required for the operation of a wind turbine, for generating electricity and for transporting the electricity produced from the turbine to the consumer. Particularly important are power cables, which carry the generated electricity through the tower to connect it to the transmission grid – but the enamelled wires used in the generators and transformers are also important. Resilient cables are used, as they are often subjected to constant movement and vibration, needing to withstand compression and torsion. In addition, they must also meet high standards for thermal load capacity, electrical insulation, halogen-free composition, as well as resistance to UV radiation, ozone, and salt water.

Eco-concept along the entire value chain
Steel plays a vital role in the energy transition: “It is an essential material in the construction of wind turbines,” emphasises ArcelorMittal. To reduce the carbon footprint of large onshore and offshore projects, it is crucial that the steel is produced sustainably. “ArcelorMittal’s XCarb® products, such as XCarb®, enable significant reductions in CO₂ emissions. The steel is made from one hundred percent recycled material (scrap) using renewable electricity. This contributes to the decarbonisation of cable production, including for wind energy.

Niehoff is also contributing to decarbonisation efforts, for example with Nexans. The companies are collaborating on the development, installation and operation of the next-generation wire breakdown system, which went into operation at the Nexans facility in Lens, France. “The plant enables optimised production speeds, which can provide significant savings of 35 kW/h per tonne, reducing energy consumption and CO₂ emissions,” the companies explain in a joint announcement. These are key investments to make the entire value chain, including for wind power, both ecological and economical. After all, only then can the industry transform to become climate friendly.

Trends and highlights from the industrial sectors of wire, cables and tubes will be presented at the world's leading trade fairs wire & Tube from 13 to 17 April 2026 in Düsseldorf. Current industry and product information can be found on the Internet portal at www.wire-tradefair.com and www.tube-tradefair.com and on LinkedIn: https://www.linkedin.com/showcase/wire-and-tube-leading-international-trade-fairs/.