Wind turbine installation vessel Pacific Orca (credit: Swire Blue Ocean)
Copenhagen-headquartered Swire Blue Ocean (SBO) plans a major fleet investment on the strength of sustained growth in the offshore wind farm sector, writes David Tinsley.
Besides a planned order for a new wind farm installation vessel offering a record-breaking lift capacity, the company intends to upgrade the capabilities of its two existing ships commissioned in 2012-2013.
SBO has shortlisted several yards worldwide for the construction of a newbuild based on a design created in partnership with the Dutch offshore engineering consultancy GustoMSC. This will be a bespoke version of the NG-20000X-G type, incorporating multiple customisations drawing on the operator’s decade of experience in the niche market.
The company described the prospective addition as “a highly competitive asset, able to work on the most difficult sites, with the largest equipment in the industry.” It is expected that the contract will carry an option on a second newbuild.
The NG-20000X jack-up design was initially unveiled by GustoMSC in 2017, driven by the increasing weight and installation height of wind turbine components and foundations, and offering a large, unobstructed deck areas to provide a variable transportation load of 16,500t.
Besides the technical planning for new ships, SBO has conducted engineering studies over the past year for the retrofit of its two Samsung-built self-elevating vessels, the 1,200t lift-capacity Pacific Orca and Pacific Osprey, with yet heavier cranes.
The projects prepare SBO for the increased challenges and opportunities presented by the fast-moving offshore wind energy sector, notably the handling requirements resulting from the anticipated scale-up in turbine size and power over the coming decade and beyond.
SBO chief executive officer Mikkel Gleerup observed that the overall development would enable the company “to deliver a solution which will prevent a supply chain bottleneck when new turbine models reach the market in the mid-2020s.”
At the time of her handover in July 2012, the 161m Pacific Orca ranked as one of the largest and most advanced wind farm construction vessels, setting a new industry benchmark for transit speed, DP2-standard station-keeping, and jacking speed, and offering a significantly improved operational weather window than other ships. Employing six jack-up legs, the Knud E. Hansen-developed design provides a transport capacity of 8,400t and the main crane is rated for a 1,200t load at 31m outreach. Sistership Pacific Osprey was completed by Samsung in early 2013.
Following extensive research conducted over the past year, working closely with the major developers and wind turbine manufacturers, SBO has defined the optimum design for replacing the main cranes on the two current vessels.
The company’s own engineers and partners have devised a crane that will provide an overturning moment of 100,000t/m while maintaining each vessel’s exceptional capacity to jack-up on difficult sites and in treacherous offshore weather conditions. The product is a solution rendering a 1,600t lift capacity with a 155m hook height above deck. These specifications are expected to meet the requirements for installation of all turbine models now under development, and to allow for the continued growth of turbine components.
The installation of the new cranes on the diesel-electric Pacific Orca and Pacific Osprey is scheduled to commence during the fourth quarter of 2023.
Each of the ships employs an ABB electric power and drive system, propulsion being achieved using four Azipod CO thrusters of 3,400kW apiece in the stern. The Azipods are complemented in station-keeping and manoeuvring modes by two bow tunnel thrusters of 2,200kW, abaft of which are two 2,200kW retractable azimuth thrusters.