Integrated Wind Solutions has signed fixed-price turnkey contracts worth €260m ($295m) for four commissioning service operation vessels at China's Nantong Rainbow Offshore & Engineering Equipment, expanding its owned fleet from six to 10 CSOVs.

The Oslo-listed company said its IWS Fleet subsidiary placed the order for the four Skywalker-class newbuilds, each priced at roughly €65m ($74m), with deliveries scheduled across 2029 and 2030. IWS has also locked in options for another four vessels at the same firm prices, for delivery slots in 2030 and 2031, subject to adjustment mechanisms covering foreign exchange and key suppliers. Exercising every option would lift the fleet to 14 CSOVs.

The newbuilds retain the Kongsberg Maritime-designed Skywalker platform already proven across the existing fleet, and will carry 3D motion-compensated cranes and gangways supplied by MacGregor Norway. IWS said it plans to fund the programme through operating cash flow and additional debt — no fresh equity — with half of the yard price payable on delivery.

The deal marks a sizeable second round of fleet expansion for the offshore wind operator. Its first six Skywalker vessels came out of China Merchants yards and are all now delivered. The scale of the repeat order signals confidence that demand for commissioning and servicing capacity in European offshore wind will keep tightening as gigawatt-scale projects reach installation phases late this decade.

For charterers and wind farm developers, a larger IWS Fleet means more dedicated CSOV tonnage arriving just as the 2029–2030 delivery window coincides with the next wave of offshore wind build-out. For IWS, the fixed-price structure and staged payment terms cap cost exposure on a $295m commitment, while the FX and supplier adjustment clauses hedge the long construction timeline.

The orderbook builds on already strong commercial momentum. In June, IWS added roughly 120 charter days and €6m to its 2026 backlog, pushing contracted utilisation for the final three quarters of the year to 94% including options — a level that underpins the debt-funded financing strategy.

Ownership of IWS Fleet remains split, with IWS holding about 75% and Japan's Sumitomo Corporation holding the balance after a €60m investment in the business in 2024. Sumitomo's continued exposure suggests appetite from Japanese industrial capital for European offshore marine infrastructure remains intact.

With deliveries spread to 2030 and options stretching to 2031, IWS has positioned itself to nearly double its fleet precisely when offshore wind servicing capacity is expected to be scarce — and its 94% forward utilisation suggests the market is already pricing that tightness in.