Offshore wind vessels have taken the spotlight in China’s offshore engineering sector.

Wind energy installation and support vessels, along with floating production, storage and offloading units, have helped fill the vacuum left by the collapse of drilling rig construction.

Though Chinese yards have achieved significant successes delivering a record number of offshore rigs and FPSOs, they are now pushing ahead to seek more diverse fabrication work catering to the ongoing energy transition.

On their radar are several new offshore products including installation vessels for offshore wind farms, floating power vessels and even floating solar cells.

In late January, Wison Offshore & Marine started construction of a novel floating liquefied natural gas-to-power project, the country’s first floating power unit to supply electricity generated by natural gas from a floating storage and regasification vessel.

The project will consist of a floating storage and regasification unit and a combined-cycle power barge with power generation capacity of 240 megawatts. Electricity generated will be transmitted to the grid.

Wison has developed technology to build 300MW floating storage and regasification power (FSRP) barges, which have received approval in principle from UK classification society Lloyd's Register.

While drilling rig jobs dry up, orders for offshore wind farm installation vessels have started to flood in.

Chinese yards are now among the world’s busiest in building offshore wind farm installation vessels.

Out of the 25 wind farm installation vessels under construction or planned globally, 16 are being built in China, including nine for domestic use and seven ordered by foreign owners, according to statistics from Chinese associations.

The latest order was awarded by Netherlands-based ThreeX BV, which signed a letter of award with Chinese yard CIMC Raffles in early February for building a heavy-lift vessel for offshore wind farm installation work.

The vessel will accommodate a 7500-tonne crane capable of installing giant next-generation offshore wind turbines, foundations and transformer platforms.

The twin-hull vessel design has been developed by Vuyk Engineering Rotterdam, a subsidiary of Royal IHC Group, and is aimed at lowering transport and installation costs for future wind farm developments.

The HLV7500 vessel, measuring 198 by 82 metres, will be equipped to lift structures to a height above sea level of 178 metres for the auxiliary hoist and 160 metres for the main hoist.

In October last year, Norway-based OIM Wind also awarded CIMC Raffles a contract for a BT-220IU wind farm installation vessel.

The unit, which will be equipped with LNG-powered engines and an onboard integrated battery pack, is expected to start operations by the end of 2022, targeting European and US markets.

Also in October last year, Norway's Offshore Heavy Transport finalised a deal with China Merchants Heavy Industry (CMHI) for the construction of a wind turbine generator installation vessel.

This year, Shanghai Zhenhua Heavy Industries is expected to deliver a jack-up offshore wind farm installation vessel ordered by Chinese contractor Longyuan Zhenhua.

The DP1 vessel, equipped with a giant crane with lifting capacity of 2000 tonnes and hosting height of 120 metres, is designed to handle the installation of wind turbines as big as 12MW.

Offshore wind installation vessels being built in China more typically offer capacity for turbines up to 6MW with the ability to lift up to 1300 tonnes.

Cosco Shipping Heavy Industry, a yard geared to construction of floating production, storage and offloading vessels, has refocused its business on offshore wind farm construction vessels.

Late last year, the yard delivered a 1300-tonne self-propelled wind power installation vessel to China’s CRCC Harbour & Channel Engineering Bureau Group.

Voltaire, an offshore wind vessel being built at Cosco’s Nantong facility for Belgian ship owner Jan De Nul Group, offers a lifting capacity of 3000 tonnes.

The vessel, equipped with a DP2 system, is capable of working in water depths of 80 metres and can accommodate 110 people.

Expected for delivery in the first quarter of 2022, the vessel is designed to transport, lift and install offshore wind turbines, transition pieces and foundations, and can be used to decommission offshore oil and gas facilities.

Just recently, Zhuhai Jutal Offshore Oil Services, one of China’s yards with FPSO topsides expertise, won a contract from Seagreen Wind Energy to build 50 mono-pile foundations for a large offshore wind farm project being developed in the North Sea off Scotland.

Jutal has delivered dozens of such foundations for offshore wind projects in China, including 15 pile foundations delivered late last year for an offshore wind farm being built near Dalian city in north-east China’s Liaoning province.

With no immediate return to the rig-building boom years in sight, yards are hoping the offshore wind installation vessel orders will continue to come their way.