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Offshore Wind Journal

Offshore Wind Journal

DEME vessel targets offshore wind and decommissioning markets

Tue 14 Mar 2017

DEME vessel targets offshore wind and decommissioning markets
DEME’s installation/decommissioning vessel will be a monohull rather than a jack-up

Large monohulls rather than self-propelled jack-ups could be the future of the offshore wind installation market, a recent order suggests

In 2012, A2SEA, the well known owner-operator of foundation and turbine installation vessels, was developing a new installation with Teekay Corporation. A2SEA got as far as sending out specifications to shipyards to obtain pricing for the project, which was based on the conversion of an oil tanker rather than a jack-up vessel.

“We want to be sure not only that the vessel can install foundations but also which types of foundation it can install. Currently, we are looking at using the vessel to install not just jacket foundations but monopiles and others,” said A2SEA. “This information, combined with the pricing for conversion, should enable us to reach a final conclusion on the project’s viability.” As the company also noted, the details of the vessel’s main crane were of vital importance.

Collaborating with Teekay, A2SEA planned to take advantage of the former’s long experience of offshore installation and its experience of operating large vessels controlled by dynamic positioning (DP).

“A2SEA is committed to developing an innovative vessel design that can cope with the next generation of foundations,” said the company. “Our aim is to provide a cost-efficient concept that is unrestricted by factors that second-generation vessels face, such as water depth,” said the company. The idea was that the vessel could take four to seven jacket foundations (depending on size). The vessel will be self-propelled, so we do not need to spend time pre-loading and jacking like some vessels.”

Ultimately, A2SEA didn’t press ahead with the plan, but the comment about not needing to spend time pre-loading and jacking was interesting because DEME, whose subsidiary GeoSea has become a well known provider of installation services in the offshore wind industry, has just placed a contract for the construction of a vessel intended to handle a new generation of larger offshore wind turbines and foundations. The vessel, Orion, will be built at Cosco in China for delivery in 2019. Although primarily intended as an installation vessel for the offshore wind industry, it will also be able to undertake decommissioning projects in the offshore oil and gas sector.

With a total installed power of 44,180kW, Orion will be equipped with a high capacity Liebherr crane with lifting capacity of 3,000 tonnes at more than 50m. The crane will be able to lift loads to a height of more than 170m. Deck space on the vessel has been maximised to provide exceptionally high transport and loading capacity. “The vessel can take the heaviest monopiles, jackets, wind turbine components and structures in a single shipment,” said DEME. “With this unmatched combination of high load and lifting capacity, Orion can transport and install the next generation of multimegawatt wind turbines.”

A DP3 vessel, Orion will be capable indeed, but perhaps the wider significance of the announcement was that, like the A2SEA vessel that didn’t quite get ordered, it isn’t a jack-up.

Jack-ups have long been the installation vessel of choice in the offshore wind industry. Numerous examples have been built, several have entered service only recently and many millions of dollars have been spent developing and building them, but DEME’s new vessel acknowledges what A2SEA knew five years ago.

As turbines get bigger and heavier and foundations get larger and larger, a jack-up probably isn’t going to provide the solution. It looks more and more likely that the installation market is transitioning from jack-ups to floating assets, and DEME’s newbuild is likely to be the first – unless of course Boskalis’s conversion of one of its F-class semi-submersible heavy lifters beats it into service. The offshore mast-type crane from Huisman for that ship is due to be delivered by the end of 2017, which means the Boskalis vessel must be due to enter service some time the following year and might just beat Orion into service.

GeoSea managing director Luc Vandenbulcke said, “With Orion, we will be uniquely positioned to meet the future requirements of our customers and the trend towards larger-capacity turbines and bigger windfarm projects, delivering energy at lower costs. Orion will be capable of installing mega monopiles in greater water depths. With DP3 technology, the installation vessel can continue operations under the most challenging conditions.”

Heavy-lifting lifting off?

Heavy-lift vessel contractors have faced a challenging market in recent years as the low oil price environment combined with a shift towards subsea installation and deepwater activity has seen fixed platform installations decline globally. The number of fixed assets installed in 2017 is expected to be around 45 per cent less than 2014 levels. This has resulted in a difficult outlook for heavy-lift vessels in the market for topside and jacket installation, leading contractors to seek out opportunities in less traditional markets.

However, as Kathryn Symes, an analyst at Douglas-Westwood in London, highlighted recently, two bright spots for heavy-lift companies are offshore wind and decommissioning – the former being increasingly attractive as the volume of installed turbines per year grows rapidly and the projects become larger and further from shore. “Though this growth has, historically, been supported by government subsidy, recent (and projected) reduction in capital costs make the technology cost-competitive with conventional forms of power generation,” she noted.

“Whilst the market for turbine installation is predominantly covered by purpose-built turbine installation vessels, installation of foundations and substations is accessible to conventional heavy-lift vessels.”

A key requirement for entering this market is sufficient deck space, with the ability to carry at least four monopiles typically preferred. Although turbine size, and hence the size of the supporting foundation, are increasing with water depth, it is unlikely that heavy-lift vessels will need lifting capacity over 3,000 tonnes. Crane capacity in the range of 1,500–3,000 tonnes is suitable for most offshore wind installations.

For heavy-lift vessels with a lifting capacity ovwe 5,000 tonnes, decommissioning represents a significant opportunity, particularly within the North Sea, which is characterised by large platforms – around 40 per cent of platforms in the UK and 85 per cent in Norway have a combined substructure and topside weight over 5,000 tonnes.

Until recently, the largest single-lift decommissioning operation had been the removal of the Frigg TCP2 MSF, weighing in at 8,500 tonnes. “With the introduction of super heavy-lift vessels such as Allsea’s Pioneering Spirit and Heerema’s Sleipnir (due for delivery in 2019) as well as recent orders from Shandong Twin Marine for two vessels with lifting capacity of 34,000 tonnes, it is hoped that the decommissioning of the North Sea’s heaviest platforms will become more efficient,” said Ms Symes.

The offshore wind and decommissioning markets both have a heavy emphasis on cost reduction, and the resultant requirement for cost-effective heavy-lift vessel solutions going forwards will be extremely important. As such, in a market where day rates are often driven by tonnage requirements, super heavy-lift vessels may have a somewhat limited market reach, and vessels that are overspecified will risk lower day rates.

Subsea 7 completes acquisition of Seaway Heavy Lifting

Subsea 7 has completed the acquisition from K&S Baltic Offshore (Cyprus) Ltd of its 50 per cent shareholding in Seaway Heavy Lifting. Following signing and completion, after close of business on 10 March 2017, Seaway Heavy Lifting and its subsidiaries became wholly owned by Subsea 7. 

Jean Cahuzac, CEO of Subsea 7, said, “Our investment to acquire the remaining shares in Seaway Heavy Lifting, such that it becomes a wholly owned subsidiary of our group, is aligned with our strategy to grow and strengthen our business in the long term. Consolidating Seaway Heavy Lifting into the group increases our participation in renewables, heavy lifting and decommissioning services. These are areas where we expect market activity to increase and see potential to grow our market share.”

The group will report revenues and net operating income from Seaway Heavy Lifting in a new business unit, renewables and heavy lifting. The new reporting structure will be reflected in the group’s first-quarter results, which will be announced on 27 April 2017.


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