Wärtsilä Engines, Thrusters for OHT's Offshore Wind Jack-up Rig
Finland-based maritime and offshore engine and equipment maker Wärtsilä has won orders to equip Norwegian firm OHT’s next-generation wind offshore turbine installation vessel being built in China.
Wärtsilä will supply an integrated propulsion and dynamic positioning thruster solution, including the engines, a Wärtsilä NOx reducer emission abatement system, as well as steerable and tunnel thrusters to deliver optimum performance for vessel dynamic positioning in this new wind turbine installation vessel (WTIV).
The jack-up installation vessel is under construction at the China Merchants Heavy Industry (Jiangsu) Co yard and is the first of two next-generation WTIVs to be added to the OHT fleet.
The Wärtsilä scope includes four Wärtsilä 32 and two Wärtsilä 20 engines, the Wärtsilä NOx reducer (NOR) system, five steerable thrusters and one Wärtsilä tunnel thruster. Delivery to the yard will take place during the first half of 2022. The WTIV is expected to be delivered during the second quarter of 2023.
The GustoMSC NG-14000XL-G design jack-up vessel will feature a telescopic crane with a maximum capacity of 2,500t and a maximum lifting height of approximately 165 meters.
"The compact design of the Wärtsilä thrusters is an important benefit since the weight of all onboard equipment can be critical for a jack-up vessel. The lightweight Wärtsilä thruster package meets this requirement while delivering excellent station-keeping capability," Wärtsilä said.
“There is rapid growth in demand for the installation of offshore wind turbines, and the vessels designed to carry out this construction work need to be state-of-the-art. The same applies to the propulsion solutions because reliable and efficient dynamic positioning is essential in all sea conditions. The full scope of Wärtsilä solutions will provide the operational and environmental performance demanded for the next-generation market,” says Torben Mikkelsen, OHT’s Newbuild Project Manager.
OHT's Wind Turbine Installation vessel ordered last year - Credit: OHT
Wärtsilä said that the vessel's effective station-keeping would be enhanced by its thrusters’ retractable system, which has an energy-efficient 8-degree tilting feature.
"This reduces the power need and, therefore, also fuel consumption. The thrusters also deliver thrust that can be up to 23 percent more effective than non-tilted units. The Wärtsilä steerable thrusters feature a modern electric steering system to provide higher redundancy, reliability, and a lower lifecycle cost," the company said. Wärtsilä did not share the financial details of the order.
In related news, OHT, which is also building a semi-submersible offshore windfarm foundation installation vessel in China, earlier this month agreed to merge with Subsea 7's renewables business with OHT Seaway 7.
The combined firm will be named Seaway 7, and will initially retain OHT’s listing on Oslo’s Euronext Growth market, with a view to a future listing on the main board of Oslo Børs. Subsea 7 will own 72% and OHT’s shareholders 28% of Seaway 7 ASA.
The two companies said the transaction would create a pure-play renewables company focused on the fixed-bottom offshore wind market.
"The company will be a single supplier providing a range of standalone, integrated, or EPCI offerings encompassing installation of wind turbines, foundations, offshore substations, submarine cables, and heavy transport," the duo said. Read more here.
