Subsea7’s order for an Energy Storage System from Bakker Sliedrecht is a double first. It is the first order for such a system on this scale for the independent system integrator. Also, Subsea7’s Seven Arctic is believed to be the first heavy construction/flex-lay vessel in the world to be equipped with such an energy saving system.
‘Bakker Sliedrecht’s Energy Storage System consists of two containerised power converters with a nominal power of 3750 kW each and 1500 kWh of batteries,’ explains Arend van der Velde, Head of Technology at Bakker Sliedrecht. ‘With this capacity, the key functions for improved vessel performance are realised by the Power Plant Optimizer control system.’
The Spinning Reserve function enables the vessel to operate safely with fewer diesel generators online and those online with a higher utilisation. When the peak dhaving function is active, the online diesel generators shift in a more optimal range with reduced intermittent starting of an additional generator. With Ramp Rate Control, the online generators are supported by the batteries in strong load fluctuations, improving grid dynamics and stability and reducing wear and tear. Based on the vessel’s operating profile, an estimated reduction of 5000 tonnes of CO2 emissions is expected.
Workshop test programme
The Seven Arctic is a heavy construction/flex-lay vessel with a total installed power of 27 MW and DP3 classification. The vessel is suitable for worldwide operations in water depths up to 3000 metres.
‘The Energy Storage System is developed in close cooperation with Subsea7 to meet their ambition to make their fleet more sustainable,’ says Andy Waterstreet, Project Director at Bakker Sliedrecht. ‘Before implementation on board, an extensive function and load test programme in our workshop will be executed. This will contribute to a shorter duration for implementation and commissioning on board.’
Highly autonomous and easy integration
‘The Energy Storage System can work with any battery or storage type,’ states Bas Oskam, Director Sales at Bakker Sliedrecht. ‘Furthermore, the control system is designed with maximum autonomy in mind, allowing for integration with different existing power- and vessel management systems on board. This makes the system very suitable to apply in existing vessels.’