Wärtsilä designs multi-purpose SOV for US offshore wind market

The Finnish technology group Wärtsilä has designed the world’s first US-flagged, Jones Act-compliant hybrid multi-purpose service operation vessel (SOV) to serve the needs of the US offshore wind power market.

The 76-metre vessel can accommodate up to 60 crew and wind-farm technicians in 55 single and five state cabins.

The vessel’s double-decked cargo space is said to provide ample room for technicians, lifting equipment, parts storage, and palletised and containerised cargo. The latter is stored in the dedicated upper deck, which can be fitted with an optional container-handling system.

Once a vessel is in operation, Wärtsilä can provide ongoing support through its Lifecycle solutions, which maintain and optimise marine asset performance for their entire operational lifespan. This support can include, for example, guaranteed asset performance with mutually agreed performance targets based on specific business needs.

”With wind energy now such big business in the US, owners and operators are taking a more strategic long-term view in terms of investments,” said Blake Jackson, Sales Engineer, New Builds, Wärtsilä Marine Business.

”The next generation of vessels has to check all the boxes in terms of IMO emissions regulations and flexible designs so that they can take advantage of technological advances as and when they become available.”

In addition to the need to comply with ever more stringent emissions regulations, a trend towards longer charter agreements is also driving this increased need for flexibility.

”We’re seeing proposals for longer agreements, in the region of 15 years, so owners need to think ahead,” said George Franssen, Account Manager, New Builds, Wärtsilä Marine Business.

”Financial considerations are another big factor because funding is far easier to obtain when the lenders have the security of knowing that the vessel has a profitable future beyond the end of the initial charter agreement.”

The SOV has been designed in close collaboration with key stakeholders including charterers, shipyards, third-party suppliers, and operators, Wärtsilä said. The designers also worked closely with classification societies including DNV and ABS.

Wärtsilä’s OPTI Design methodology, a data-driven approach that focuses on the vessel’s total propulsive efficiency, will be applied to achieve the perfect balance between propeller, engine and hull, the company said.

Rather than simply adding a propulsion system to a finished vessel design, with this approach the two are designed simultaneously. Wärtsilä’s experts take a holistic approach, using their knowledge of computational fluid dynamics and other techniques to optimise the design of the vessel.

”This means we can determine the effects of interaction between the propulsion unit and the vessel itself and use the information to deliver optimal efficiency, reduced costs and emissions and maximised performance,” said Jackson.

Furthermore, the vessel design also benefits from Wärtsilä’s patented Low Loss Concept (LLC), an energy-efficient and highly redundant power distribution system for electric propulsion applications.

The design integrates a range of Wärtsilä’s green systems and solutions, including shore-charging cold iron systems and a hybrid powertrain employing a containerised battery-on-board energy storage system. This allows for peak shaving, helping the engines to run at optimal load, thereby lowering both emissions and maintenance costs. The design also includes space for the integration of potential future powerplant and fuel technologies such as hydrogen fuel cells.

Two boat landings enhance the safety and efficiency of operations by providing dedicated safe-passage zones for technicians transferring to and from crew transfer vessels. Wärtsilä SmartDock, an automated system that enables consistent and repeatable docking to complement the capabilities of the crew, further increases safety, improves operational performance and reduces both fuel consumption and wear and tear. Operators can also benefit from Wärtsilä’s Smart Voyage Optimisation solutions to further improve fuel efficiency and safety.

To ensure safe operations in all sea conditions, the multi-purpose SOV features Wärtsilä’s own dynamic positioning system that is fully integrated with the vessel’s propulsion system. This supports, for example, the vessel’s walk to work system, where technicians access the working location via a centrally located 3D motion-compensated gangway integrated into the structure of the vessel.