Following Boskalis’ earlier announcement to hybridise numerous existing vessels, Bakker Sliedrecht implemented energy storage systems on the two diving support vessels Boka Atlantis and Boka Da Vinci. The systems reduce the vessels’ fuel consumption and associated emissions by an average of up to twenty per cent.

The systems also provides a power supply and energy storage facility while the vessels are docked and contribute to quieter and more efficient operations offshore.

Both vessels were converted in a short period of time at the Boskalis Service Center quay in Rotterdam. Bakker Sliedrecht’s scope of supply included a battery pack, a power converter system, a transformer, switchboard panels, an energy storage system (ESS) control system with several functionalities, such as spinning reserve, peak shaving, ramp rate control, state of charge management and battery management. Also, system design, engineering, production, physical and functional integration and commissioning were included.

Also read: Bakker Sliedrecht to fit Energy Storage System on Subsea7’s Seven Arctic

Short out-of-service period and maximum redundancy

With the current busy market for subsea vessels, minimising downtime is key for vessel owners.

‘We managed to limit the out-of-service time of these vessels, from arrival of the vessels up to completed sea trials and class approval, to less than two months for the whole ESS implementation,’ says Andy Waterstreet, project director at Bakker Sliedrecht. ‘This meant careful offline preparation was important and this included a detailed onboard survey beforehand and extensive in-house functional testing of the ESS at Bakker’s test facility.’

Further reduction of fuel consumption, emissions and running hours was achieved by optimising the power plant configuration.

‘For DP2 vessels performing very safety critical operations like these vessels, redundancy and safe operations are key in every design choice,’ explains Edwin de Koning, account manager at Bakker Sliedrecht. ‘This was achieved by early involvement of and close cooperation with DNV-GL, execution of extensive failure mode effect analysis and sea trials.’

Also read: Boskalis commissions new cable-laying vessel Boka Ocean

Integration

Although these vessels are originally not equipped with a Bakker Sliedrecht provided diesel-electric power plant, both physical and functional integration went smoothly. The company’s experience in system integration, which involves systems from different vendours and the autonomous, in-house designed ESS control system, highly contributed to this.

Also read: Bakker Sliedrecht upgrades Boskalis’ cutter suction dredger Taurus II