Van Oord has given its heavy-lift vessel Svanen a new lease on life with a major upgrade that is nearing completion. SWZ|Maritime was invited to come and see what the vessel now looks like while it is still in the Port of Rotterdam.
The Svanen is mostly used to install monopiles and its specifications make it ideally suited for installation jobs in the Baltic Sea. An area that will see a lot of offshore wind projects being realised in the coming years.
To this date, Svanen has installed about 700 monopiles and 223 transition pieces with yearly increasing dimensions and weights. However, with the ever larger offshore wind turbines, the 34-year-old Svanen needed an upgrade to still be able to handle the accompanying monopiles. A job Van Oord was willing to take on due to the increase in offshore wind projects in the Baltic Sea and the limited availability of capable vessels to install the future monopiles.
In addition, Van Oord states that, the vessel’s design had room for increasing the working operational specs. The ship already had proven reliable technology on board which made it suitable to upgrade. The Svanen has a relatively simple construction and operation as well and since the several owners have maintained it well, technical upgrades were relatively easy to implement.
Of course, an upgrade is also faster to complete than building a new vessel and Van Oord was happy that the upgrade would allow them to make use of and upcycle existing materials.
Also read: VIDEO: Growth spurt for Van Oord’s heavy-lift vessel Svanen
How the Svanen operates
The Svanen has a slot of metres between its two hulls. A monopile is brought into this slot by another vessel after which it is attached to one of the Svanen’s hooks. By simultaneously letting the monopile fill with water to make it sink into the water and lifting it, the monopile comes upright and is fitted into the gripper for installation.
The Svanen is not equipped with dynamic positioning (DP), but uses its eight anchors fitted in a star-like shape around the vessel to get into and stay in position. Once the anchors have been deployed, they are controlled by a joystick allowing for pinpoint precision to obtain the right position.
Once in position, a hammer drives the monopile into the seabed. The Svanen is equipped with a noise mitigation system, which encloses the hammering operation. In addition, bubble screens can be deployed around the vessel to reduce the noise from pile driving further. It takes the Svanen 22.8 hours to install one monopile.
Also read: Mammoet’s largest crane to install new A-frame Svanen
History of the Svanen
In 1990 the Svanen was built with re-using hoist winches, anchor winches, sheaves, main engines and propulsion units of the Ostrea and Macoma. It started its operational life in 1991 with a lifting capacity of 6500 tonnes and lifting height of 48.5 metres above deck.
In 1995 the Svanen was beached near Dunkerque in a graven dock and modified for construction of the Confederation bridge in Canada, the modification consisted of:
- Lift height above main deck increased to 74.5 metres (additional 26 metres) and capacity to 8700 tonnes including lifting gear.
- Pontoons widened.
- Subsea dry tank added to compensate for additional steel in the gantry.
- Propulsion units forward added.
- Auxiliary crane on top of gantry added.
- Two containerised powerpacks added on forecastle deck.
In 2005 the Svanen was modified for installation of monopiles and transition pieces with the installation of a pile gripper on the starboard pontoon and containerised extra accommodation on top of the wheelhouse for 48 pax.
In 2014 Van Oord acquired Ballast Nedam Offshore including the Svanen. This was followed by modifications in 2016 where extra accommodation blocks were fitted on portside for additional 26 pax. and a fixed auxiliary Liebherr crane on the portside pontoon was fixed.
In 2017, more modifications followed. A central gripper and hammer frame (for monopiles with a length of 87 metres and a diameter of 11 metres) were installed. Four hoisting hooks were modified to two spreader beams: 1200 tonnes and 1700 tonnes. Furthermore, both a noise mitigation system and lifeboats on portside and starboard were installed.
Also read: Svanen uses bubbles to silently install offshore foundations in Denmark
Current upgrade
To meet all the requirements, a general scope of modification was compiled. First of all, and most noticeable, is that the gantry had to be extended by about 25 metres. In early May, the A-framed gantry extension, weighing about 1200 tonnes and built by Holland Shipyards Group, was lifted by Mammoet’s new PTC ring crane and fitted on top of the Svanen’s existing gantry. An operation that took about 2.5 hours.
Hull reinforcements were also needed to take the additional loads. Hull modifications included strips along the flat bottom of 35 metres, closing the bow to reduce draught, and the gantry deck interface was strengthened. The distance between both hooks had to be extended by 2 metres and the bracings had to be modified for additional height hammers.
The aft spreader beam had to be upgraded to 3000 tonnes WLL including a new hook design. At the same time, the forward spreader beam was also upgraded to 2000 tonnes WLL.
Finally, the accommodation was also addressed. The Svanen received updated cabins, including ten single-bed cabins, an additional leisure area, a renewed and enlarged galley, and up to date internet connectivity and WiFi.
All in all, this is expected to add ten years to the vessel’s operational life.
Also read: Van Oord wins large offshore wind project in Poland
What’s next?
The Svanen is currently still moored alongside in the Heysehaven Rotterdam. Final commissioning of systems has been completed, while first testing has started. The load test, which will see a load of 4950 tonnes lifted, is planned for late August.
Outfitting for the coming projects is expected to ramp up from the middle of September. Currently, a lot of auxiliary equipment is being fabricated. The Svanen will be ready to sail to the Baltic from the 1st of October. The vessel will work on three offshore wind projects consecutively, Baltic Power, Windanker and Baltica 2.
Start of the next project Baltic Power is 1 January 2025. Baltic Power’s offshore wind farm area of approximately 130 km2, located 23 km to the north of the Polish coastline, will feature 76 wind turbines, each with a generating capacity of 15 MW. The Svanen will install eighty monopiles for this project.
Windanker is located in the German waters of the Baltic Sea and will reach an installed capacity of 315 MW with 15-MW turbines. For Windanker, the Svane will install twenty monopiles.
For Baltica 2, 111 monopiles for 14-MW wind turbines will be installed by the Svanen. The Baltica Offshore Wind Farm will be developed in the Polish part of the Baltic Sea between Łeba and Ustka, with Baltica 2 having an approximate capacity of 1.5 GW.
Picture (top): View of the slot and monopile gripper between Svanen’s two hulls (all pictures by SWZ|Maritime unless otherwise indicated).
Also read: Van Oord starts UK offshore wind project and wins one in Baltic Sea
