Great Lakes Dredge & Dock (GLDD) has ordered the first US-flagged and Jones Act compliant subsea rock installation vessel. Designed by Rotterdam-based Ulstein Design & Solutions, the first vessel will be constructed by Philly Shipyard and is expected to enter operations by Q4 2024 to serve the US offshore wind market.
The vessel is of the Ulstein S211 design. Following the basic design contract in December 2020, GLDD contracted Ulstein to continue the project with the integration engineering for the new dynamically positioned rock installation vessel in April. The shipbuilding contract signed now includes an option for a second vessel.
Shore power and battery packs
To reach the low emission and sustainability goals, the vessel design includes EPA Tier 4 engines, plug-in shore power connection for loading in ports and battery packs for peak-shaving. The vessel is also able to run on biofuel to reduce CO2 footprint and is equipped with active emission control technology to minimise NOx emissions.
In the concept phase the Ulstein Blended Design method was used to enhance cargo efficiency, to boost the GLDD business case, and reduce overall fuel consumption.
The particulars of the vessel are:
- Loa: 140.5 m / 461 ft
- Lpp: 134.9 m / 442 ft
- Beam (moulded): 34.1 m / 112 ft
- Depth (main deck): 10.7 m / 35 ft
- Draught (operational): 7.0 m / 23 ft
- Service speed: 12 kn
- Installed power: 2 x 3150 kW / 2 x 2250 kW
- Propulsion thrusters: 2 x 2500 kW
- Retractable thruster: 2 x 1200 kW
- Tunnel thrusters (fwd): 2 x 900 kW
- Positioning system: DP 2
- Class: ABS
- Rock hold capacity: 20,000 t
- Complement: 45 P