Windea Leibniz is the second of two service operation vessels (SOVs) built by Ulstein Verft for Bernhard Schulte Offshore and ICBC Leasing.
Ulstein Verft received a shipbuilding contract from Bernhard Schulte for two service operation vessels (SOVs) of the ULSTEIN SX175 design in January 2015. The first vessel in series, Windea La Cour, was delivered in June 2016, followed by the second SOV in February 2017.
The second vessel was christened as Windea Leibniz in March 2017. It will be deployed at the Siemens’ Sandbank wind farm in April 2017.
The SOV will support a range of operations, including wind farm installation and maintenance, and accommodation and transportation of technicians for offshore installations.
Design and features of the service operation vessel
The Windea Leibniz SOV is based on the SX175 design developed by Ulstein Design & Solutions. The new vessel features the X-BOW hull line design and X-STERN solution from Ulstein Group. These innovative design elements ensure reductions in wave response and slamming, while increasing comfort for the crew aboard.
The X-BOW design features a pointed forward hull with sectional angles, allowing it to pierce through small waves, while minimising pitching and bow impact loads in high waves. The X-BOW hull, in comparison with bulbous bow designs, offers a higher deracination volume commencing from the waterline.
The X-STERN design replaces the transom plate with a pointed aft, resulting in a sharp stern shape that helps the ship to remain steady in waves, strong winds and currents.
The positioning of stern towards the weather in place of the bow will reduce pitch motion, while the overall design will reduce propulsion power use by up to 50%.
Windea Leibniz has a length of 88m, a beam of 18m, a maximum draught of 6.4m, and a deadweight of 3,150t.
Windea Leibniz SOV deck equipment and capacities
The vessel features a large cargo deck area of 380m². The on-board crane can lift equipment and spares onto the wind turbine platform. The on-board motion compensated walk-to-work gangway system enables the transfer of maintenance team to the wind turbines in wave heights up to 2.5m or above. The vessel also houses workshops to perform maintenance operations at the wind farms.
The landing platform at the forward bow section allows for the landing / take-off of a single helicopter. The helicopter operations ensure the rapid transfer of personnel and equipment during wind farm installation and support missions.
The SOV is also equipped with IMO Class II dynamic positioning system assigned with DYNPOS-AUTR notation from DNV.
The vessel has the capacity to hold 1,150m³ of fuel oil, 1,200m³ of fresh water and 2,400m³ of ballast water.
The SOV offers accommodation for 60 personnel, including 40 service technicians and 20 crew members, in single cabins.
The vessel also features a mess room and a day room for technicians aboard the SOV.
Windea Leibniz SOV propulsion
The propulsion system integrates two frequency-controlled variable-speed electric motors driving a pair of azimuth thrusters. The ship is also equipped with a retractable azimuth thruster and two side thrusters at bow section.
The propulsion system complies with the IMO Tier III NOx emission standards and allows the vessel to sail at a maximum speed of 13.5kt.