ROV LARS ordered for Sea1's offshore energy construction vessels

Sea1 Offshore will install launch and recovery systems (LARS) for remotely operated vehicles (ROVs) on four newbuild vessels under construction in China.

COSCO Nantong is building four methanol-ready battery-hybrid offshore energy construction vessels (OECVs) for the Norwegian owner based on Skipteknisk’s ST-245 design and DNV class for delivery from 2027.

These 120-m subsea construction vessels will have 1,400 m² of clear deck space, accommodation for 120 and will be equipped with a 250-tonne subsea crane and two integrated hangars for work-class ROVs with side-launch capability. Two LARS for these ROVs will be supplied by Kongsberg Maritime to support subsea construction, inspection and maintenance operations.

Kongsberg’s scope of supply per vessel includes two telescopic A-frames, electric-powered umbilical winches, energy-efficient hydraulic power units and a dedicated control system. Each system will have a safe working load of 15 tonnes and winch cable capacity of 4,500 m for ultra deepwater operations.

“We are confident the work-class ROV launch and recovery systems will give us market-leading operability in harsh environment operations with the equipment fully integrated to the vessels’ power electric and energy storage systems,” said Sea1 Offshore chief commercial officer Andreas Kjøl.

The inclusion of hydraulic power units with frequency control reduces emissions and energy consumption, supporting sustainability goals without compromising operational capability. Control systems provide precise and responsive handling, enabling safe and accurate operations for complex subsea tasks, said Kongsberg.

Kongsberg is also providing technology for these Sea1 newbuilds including its K-Pos dynamic positioning systems, integrated control and navigation systems, battery-hybrid direct-current electrical systems, main propulsion and thruster units.