Cable company Nexans tells Kelvin Ross why it’s bullish on the European offshore wind market and highlights its key projects

The Hywind floating offshore wind farm

Credit: Statoil

Submarine cable company Nexans is bullish about the long-term potential of the European offshore wind sector.

The company estimates it has up to a 25 per cent share of the 27 GW of capacity it says is currently under construction in European waters.

Morten Langnes, Nexans’ submarine high voltage cable sales manager, says: “Europe is our biggest market – in terms of offshore wind, it’s everything for us.”

He adds that the sector is “booming” and stresses that “as long as it’s like this, there’s no point in trying to go anywhere else”.

“Momentum in the European market is still strong – and we see it staying very strong for another 10 years at least.”

Nexans – which installed its first submarine cable in 1949 – is involved in various types of offshore wind projects in Europe, from the very large to small-scale experimental.

This year it won a €245 million ($261 million) contract along with Siemens Transmission and Distribution to connect the 588 MW Beatrice windfarm, which is off the coast of Scotland and will comprise 87 turbines.

The Skagerrak cable-laying vessel

Credit: Nexans

Nexans will manufacture and deliver two circuits of 90 km, with a total of 260 km of onshore and offshore cables, and these offshore cables will be laid by Nexans’ unique cable-laying ship, the Nexans Skagerrak.

The Skagerrak was built in 1976 and has been in almost constant use ever since. To illustrate just how much it is purpose-built, Nexans had to cut off one metre from the ship to ensure it could fit through the Panama Canal to fulfil a contract in 1982. “It shows what we are capable of and what we are prepared to do,” says Langnes.

The Beatrice project will also see Nexans utilize its Capjet technology, an air-blasting trenching system for submarine cables, umbilicals and pipelines. Introduced in 1986, it has since buried 8000 km of cables and Langnes says: “This is our baby – it’s designed in-house. It’s a very friendly way of doing it in terms of the environment but also in terms of the cable.”

Langnes explains that developing its own bespoke equipment such as Capjet and the Skagerrak vessel has allowed the company to reduce the time it takes to install submarine cables. Work on an offshore windfarm typically involves around 1750 km of cables and between 40 and 50 people.

“You plan for three years and you finish it in one week. You need to be prepared – you need to bring a spare part for everything.”

Nexans’ offshore wind work does not just include large-scale projects. It is working with Statoil on the energy giant’s floating windfarm Hywind, also located in Scotland, 30 km off the coast of Aberdeenshire.

Following a demonstration project in Norway which started in 2009, Nexans is now involved in the 30 MW Scottish pilot project and will supply static and dynamic cabling.

The windfarm will comprise five wind turbine generators connected through an inter-array cable network before feeding into a single export cable carrying energy back to land in Peterhead.

Langnes says that, at the moment, installing floating wind turbines is “a bit more complicated than traditional offshore wind”, however he sees a definite place in the market for the technology.

“You can be more flexible on where you put your wind farm for whatever reason – it could be environmental, it could be because the public doesn’t want it on their beach. And the further you go offshore, then the winds are a bit more steady, so they generate more power and with a floating turbine the idea is to have larger turbines.”

He acknowledges that floating turbines will make construction and maintenance more complicated, “which is why we’re now building small-scale just to test it”.