Too Many Turbines, Too Few Vessels

By Jeremy Bowden

A dearth of installation vessels for wind turbines and foundations is hindering Europe’s offshore wind development. Industry leaders from Jumbo Offshore, Zero-C Offshore, Allseas, and OEUK discuss how the sector should respond.

From Issue 2, 2024 of Breakbulk Magazine.


Over the next 10 to 15 years a massive roll out of offshore wind farms is planned.

In Europe alone, the UK, Germany, France, Poland, Holland and Belgium have a combined offshore wind generation target of 140 gigawatts (GW) by 2030, with the UK the largest constituent at 50GW. The size of turbine is increasing as is the average depth, while some next-generation offshore grid systems require 2GW converter stations, all of which need to be put in place.

While attention so far has mostly been on rising costs and bottlenecks in turbine manufacture and supply, the focus is increasingly switching to installation constraints, especially in the field of heavy-lift vessels, or HLVs.

Last August, Ørsted cancelled the major Ocean Wind 1&2 projects off the coast of New York, which, while officially blamed on “supplier delays”, was put down specifically to the inability of the operator to secure an appropriate HLV vessel within the allotted time frame, according to David Carr, joint CEO at Zero-C.

The Norfolk Boreas project off the coast of East Anglia was also cancelled in 2023, due to rising costs, and the two cancellations have eased the vessel shortage situation, at least temporarily. More leeway could be gained from further delays to wind farms from contract renegotiation or rising costs elsewhere.

Nevertheless, the situation does look tight.

The global fleet of installation vessels was originally a blend of heavy-lift ships and small general-purpose jack-up rigs able to manage smaller installations, but turbines are getting bigger requiring larger foundations and installation vessels, while farm size is also growing, resulting in larger loads that require bigger vessels, as well as more cable and other work. Analysts predict that over 100 new offshore wind turbine and foundation installation and maintenance vessels will be required for offshore projects planned over the next decade.


Complexity Dictates Vessel Demand

The complexity of installation varies by country depending on geology, water depth and weather conditions – which determine the type of vessels required. A lot of wind means more waves and a more complicated environment, according to Carr, while water depths of over 100 meters in the ScotWind areas are a significant factor. “Whereas in the Baltic it’s only 30 to 40 meters of water so there are a great many more vessels that can do that work.”

Carr said the largest 20 megawatt (MW) turbine deeper water windfarms require pyramid structure jackets rather than monopiles, 110 meters in height, weighing 3,000-4,000 tons.

“Four vessels in the world can do these project foundations – Heerema Marine Contractors Sleipnir and Thialf crane vessels, the Saipem 7000 and Les Alizés – which are all contracted to the end of the decade in North America. Les Alizés is contracted out to RWE until 2029 at US$225,000 per day, and Saipem 7000 is on a US$450,000 day-rate in oil and gas – rates much higher than for wind projects,” leaving no suitable vessels available.

Brian Boutkan, manager commerce offshore at Jumbo Offshore, agreed there was a “positive market outlook” for HLV transport, and he acknowledged that European fabrication yards may not have the capacity to keep up with the required pace of development of new vessels for offshore wind in Europe. But he suggested that the additional vessels required could come from China, South Korea and elsewhere in East Asia.


New Vessels in the Pipeline

Many new vessels are being commissioned by European companies.

Ulstein has developed a new class of turbine installation vessel able to lift 8,000-tonne foundations, while offshore services company Van Oord has ordered a new offshore wind turbine installation vessel that will be able to install next-generation wind turbines of up to 20MW with a low carbon footprint. The vessel will be built by Yantai CIMC Raffles Shipyard in China and delivered in 2024.

Once the foundations are in place, a wind turbine installation vessel, or WTIV, puts on the turbine. Some vessels can do both. Havfram Wind ordered a second NG20000X Jack-Up vessel in late 2023, capable of installing offshore wind turbines with a rotor diameter of over 300 meters, as well as monopiles of up to 3,000 tons in water depths of 70 meters.

According to the CEO, the vessel has several wind farm commitments, including with Ørsted to install wind turbines at their Hornsea 3 project, starting in autumn of 2026. Vattenfall has appointed Havfram as preferred supplier for the Norfolk Projects, starting in the spring of 2027.

Other newbuild WTIV orders have recently been announced by several companies including Cadeler, OHT and Eneti. And in December, IWS of Norway took delivery of its second (of six) CSOV (wind farm mothership) for North Sea service from China. The vessel will start work on the Dogger Bank wind farm early this year.


Still Not Enough?

Carr said that in the past decade, a number of next-generation WTIVs had been built, “but not enough for the 2025 demand increase, and it’s a similar story for FIVs [floating installation vessels, aka HLVs], which take three years to build.” An additional challenge comes from training crews from scratch.

Carr said: “The supply chain hasn’t matched developers in the rush for wind power... Most investment is currently going to oil and gas installation vessels because returns are much higher.” He added that suggestions that Transocean might convert existing older rigs or rigs that were not completed due to the Covid slump to wind installers were unlikely to come to fruition because of those higher returns in oil and gas. “Wind rates have risen but need to rise further,” he added.

However, major marine services provider, Allseas, told Breakbulk that it had vessels available for the development of offshore wind, with its latest HLV, Pioneering Spirit, “a gamechanger.” The newly built vessel can transport and install entire platform topsides up to a weight of 48,000 tons, prefabricated and tested onshore, with plans to increase this to 60,000 tons. So far it has installed jackets and converter stations, but not turbines.

“Our capacity for installation (and removal) of such large topsides is extremely high due to the fast and robust heave-compensated lift equipment that provides good workability for single-lift installation in North Sea conditions, even in wintertime. Pioneering Spirit can also install jackets weighing up to 20,000 tonnes in a single lift, thereby limiting subsea work and associated risks,” Allseas said.

The Swiss-based company said its main wind challenges are schedule and logistics. “Installations will need to be staggered and planned in such a way that Allseas can continue to serve other clients outside the wind industry.” It added that the transport market was under pressure due to fast-growing demand and the growing size of the platform components.

In September 2022, Allseas installed the 900MW DolWin kappa converter station for TenneT’s DolWin6 offshore grid connection system. Comprising a 5,000-ton jacket and a 11,000-ton converter station, it was Pioneering Spirit’s first complete platform installation for the wind industry and took only 12 days to complete in the German North Sea.

Since then, Allseas has secured a number of wind installation deals. “Southern Europe, Australia, Asia and China are also potential future markets for Allseas. In the short term, however, the focus will be serving operators expanding developments in the North Sea.”


Tight UK Market

Offshore wind projects are also stimulating the commissioning of new cable-laying vessels, with vast amounts of work associated with wind farms, while the limited number of existing vessels are mostly dedicated to international subsea communications networks and oil and gas. New orders include two newbuilds from Megamas in November, with the first to be ready in 2026.

The situation is particularly tight in the UK, where plans for offshore wind are deepest and the most ambitious. Offshore Energies UK forecasts the number of turbines requiring installation will increase from over 200 in 2026 to almost 400 in 2031, provided the UK remains on course for its 50GW wind capacity target by 2030. In addition, about GBP£3 billion will go to heavy-lift/topside removal of old oil and gas rigs over the next decade, with a series of huge platforms to be removed from 2027 onwards.

OEUK Decommissioning Manager Ricky Thompson told Breakbulk that, in terms of heavy lifting, the larger and deeper water oil and gas structures will come away from 2027 onward, while most of the decommissioning of the smaller topsides will take place over the next few years in the southern North Sea and Irish seas. Thompson said this alone was “going to need a colossal push from the heavy-lift market.”

“We’re also expecting a surge in the demand for these vessels as offshore wind scales up in deeper waters – requiring more help from the decommissioning supply chain.” Issues remain in terms of shared skills and assets for offshore wind installation and oil and gas removal works, but he said the cost of removing topsides had fallen and this was expected to continue.


Working Together in Offshore

Thompson said the system may be able to cope: “Clever scheduling and fresh contracting models may be the answer to delivering such an abundance of work. An integrated offshore sector working together is needed to ensure collaboration, innovation and potentially infrastructure investment to enable this. Activities across these industries will be sharing the heavy-lift space for the next decade, so cooperation and some new assets will be important.”

There are also moves to create a local UK provider, headed up by Carr and his colleagues. Formed last year, startup Zero-C Offshore Construction plans to become a UK “Tier 1” for HLVs through development of a fleet (probably two) of ultra-low emissions Installer Max foundation installation vessels working from UK ports. The firm is hoping to secure a multi-year charter, against which it can finalize investment.

Carr said the UK has the highest aspirations for offshore wind, and yet there are no Tier 1 contractors in the UK to install, let alone to build these wind farms. “Scottish & Southern Electricity is bidding for a CFD for Berwick Bank [proposed wind farm] in the next few months – if they get it, they need to make progress quickly but do not have an HLV for installation of foundations yet, with start date planned for 2027. This means Berwick Bank may be delayed or sold.”

Current vessels can only install one to two of the largest type of foundations at a time, but Zero-C plans vessels that can manage three to four, improving efficiency, according to Carr. “Our new design would expand the working season and may be able to install the turbines too – which has not been done with floating vessels yet, but in calm weather we think it can be done.”

Carr said they needed stable long-term government policy to enable big companies to commit; wind support vessel orders reportedly fell sharply in 2023 when government policy appeared to waver.

He added that operators are also concerned about write-offs associated with work in the wind sector, especially when there are lucrative alternatives in oil and gas. “There’ve been hundreds of millions of dollars of write-offs – legacy construction terms applied to wind orders, larger contractors took all the risk and things went wrong; late delivery, etc.,” Carr said.


Next Generation Installation

Allseas said it was also developing new concepts for the installation of next-generation turbines and foundations in the UK and elsewhere. The Swiss-Dutch company said it had various contracts for the installation of both gravity-based and jacket turbine foundations, which were “within the capacity of existing lift systems, and we still have installation capacity for the coming years.”

It added that availability would largely depend on how successful Allseas is in securing future work for the installation of heavy pipelines and/or heavy-lift operations at remote locations.

More overseas capital is also flowing into the UK sector, which many see as at the forefront of global offshore wind. Recent deals include Singapore’s Cyan Renewables buying up Aberdeen-based Sentinal Marine, which it plans to use “to pivot and capture a slice of the fast-growing offshore wind market in the UK,” according to the CEO. Further deals and investment are expected,” Carr said, “despite a deteriorating investment climate linked to unsupportive government policy.


Ørsted is a member of the Breakbulk Global Shipper Network.

TOP PHOTO: Allseas installed the 900MW DolWin kappa converter station for TenneT’s DolWin6 offshore grid system. CREDIT: Allseas

SECOND PHOTO: Ulstein has developed an 8,000t foundation installation vessel. CREDIT: Ulstein