Page 34: of Offshore Engineer Magazine (Mar/Apr 2023)

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FEATURE WIND TURBINE INSTALLATION VESSELS (WTIV)

Vessels at ABB Marine & Ports. retraction and steering systems. Wärtsilä’s references also “For WTIVs, this means everything from exact posi- include supplying thrusters for two WTIVs being built for tion keeping, to normal voyage maneuvering that would the China Three Gorges Corporation.

be previously handled by the auto-pilot is done in the same There are currently 11 WTIV active or under construc- system, using the same controls,” Thue says. “ABB Ability tion able to work in 70m water, plus Jan De Nul's newest

Marine Pilot Control supports consistency in operations, wind turbine installation vessel, Voltaire, which has legs reducing the impact of varying operator skill levels on com- 130 meters tall and can work at unsurpassed water depths plex maneuvers. This will be measured in greater time ef- up to 80 meters. fciency in operations and in improved energy effciency.” However, Philip Lewis, Director Research at Intelatus

A key part of operational effciency is fnding a combina- Global Partners, says: “There are a multitude of factors other tion of thrusters that achieve high performance in transit than water depth to consider, including the appetite of ves- and for dynamic positioning, combined with light weight. sel owners to invest in new vessels, given the speed of techni-

Wärtsilä is supplying such a package to Eneti’s Nessie and cal change in turbine sizes and foundations and their ability

Siren WTIVs, seven units each. to pay-back the investments before having to upgrade.”

The thruster solution includes 8° tilted retractable New-generation WTIVs will help meet growing de- thrusters to achieve high thrust with limited power. The mand in core European/Taiwan markets, new European propeller shaft tilt reduces the interference between the markets (Mediterranean and Baltics), South Korea, Japan, thruster wake and the fat-bottomed hull, increasing the US, and Australia, says Lewis. Demand in these markets is bollard pull by up to 20% and reducing fuel consumption. set to grow strongly after the middle of the decade.

Wärtsilä can further minimize the vessel's environmental Even so, water depth will ultimately limit the outward impact with retractable thrusters that have full electrical march of fxed turbines and, with them, jack-up WTIVs.

Jan De Nul's newest wind turbine installation vessel,

Voltaire, has legs 130 meters tall and can work at unsurpassed water depths up to 80 meters.

Jan De Nul 34 OFFSHORE ENGINEER OEDIGITAL.COM