Dutch shipbuilder Damen has announced the launch of a fully electric version of its 70-meter hybrid service vessel SOV7017E, designed to support offshore wind farm operations. The company aims to charge batteries directly from wind turbines. Swarms of giant turbines harvesting wind energy are increasingly common on coastlines around the world, but the ships used to service them aren't as clean and green as they should be. This is where the SOV7017E comes in.
Damen currently offers four service operation vessels, ranging in length from 60 to 88m (196.8-288.7 ft), capable of accommodating 44 to 120 personnel at a time, all equipped with hybrid diesel/battery propulsion systems with four-azimuth thrusters.
The new 70.1-meter (229.9-foot) electric vessel is also equipped with two HVO/diesel generators, but these are for emergency or backup purposes only. The 7017E is equipped with a 15MWh lithium iron phosphate battery system, which can achieve approximately 98% of all-electric operation throughout the day, or with a 10MWh battery pack, which can achieve 75% of all-electric operation. The propulsion system consists of four 900kW azimuth thrusters arranged at both ends. Top speed is 12 knots.
Damen has partnered with UK-based MJR Power & Automation to develop a new offshore charging solution that uses the ship’s motion-compensating ramp to bridge the gap between the ship and the wind turbine or offshore substation, and allows the battery pack to be charged via a 4-MW/11-kV connector while the 7017E is in low-power mode at sea.
A single turbine can fully charge the ship's batteries "in just a few hours." Of course, wind turbines and offshore substations will need to be equipped with offshore charging stations to provide interfaces, and existing offshore infrastructure will be utilized as much as possible. The ramp is controlled from the driver's cab, and plugging and unplugging during charging "requires no human intervention." MJR is currently developing an 8MW offshore charging solution to enable larger ships in Damen’s fleet to become fully electric.
The ship can be configured with 60 cabins equipped with Wi-Fi and video-on-demand services, can accommodate up to 40 technicians and crew, and also comes with storage space, workshop, restaurant, gym and games room.
Damen’s Mark Couwenberg said: “The product launch of the SOV7017E shows that this technology can enable offshore operations to be fully electric. Harvesting energy directly from offshore wind farms means the reduction in operating costs means there is a business case for this model. However, we cannot do this alone. To achieve this, it requires cooperation across the chain, including with shipbuilders, ship operators and ship manufacturers.”