New offshore wind feeder vessel concept features motion compensation

Image: C-Job/Ampelmann

One solution to installing offshore wind turbines in compliance with the Jones Act is to use a foreign-flagged wind turbine installation vessel (WITV) supported by U.S.-flagged, U.S.-built feeder vessels.

Two Dutch companies — offshore access specialist Ampelmann and C-Job Naval Architects — have joined forces to develop a feeder vessel, specifically suited for the rigorous demands of operating off the U.S. East Coast, incorporating motion sensor technology.

The concept design combines the knowledge of Ampelmann, the Dutch offshore access provider, and independent ship design company C-Job Naval Architects. Together they have created a viable solution in response to the need to support the construction and logistics of offshore wind farms in the United States under the Jones Act.

The state-of-the-art offshore wind feeder vessel has an L-shaped superstructure. This enables the transport of all wind turbine components, including the blades, while keeping the ship itself relatively compact, minimizing construction and operational costs. To maximize workability and allow for safe lifting of the components, the feeder vessel features a specially designed motion compensation system by Ampelmann.

MOTION COMPENSATOR

The system uses Ampelmann’s core technology to stabilize the wind turbine components in six degrees of freedom and is designed for safe lifting operations in sea states up to 2.5 m significant wave height. The compensator is positioned close to the vessel’s center where it can compensate for all vessel motions and allows for continued operations – even in adverse weather conditions – throughout the year.

Gus DeOliveira, Ampelmann’s business development area manager for the Americas, says: “We see a lot of potential for the offshore wind market in the U.S. and believe that we can add some unique value based on our decades-long experience in the offshore wind market. Our partnership with C-Job is crucial if we are to design and deliver just the right solution for this growing market.”

The wind turbine components are arranged on the ship with a quick-connect grip-and-glide system. Cargo pallets are placed on deck quickly thanks to the quick-connect system. Once the feeder vessel is at its destination, the system slides the components into place to connect to the motion compensator. The Ampelmann system then compensates all vessel motions, so the crane operator can lift turbine components in a similar fashion to an onshore lift.

Todd Allen, VP Business Development at C-Job Naval Architects, says: “Together with our strategic partner Ampelmann, the experts in motion compensation, we have created an innovative ship design ready to support construction of U.S. wind farms today and into the future.”