Saft has been awarded a contract by ABB Marine to supply a specialized high power liquid cooled lithium-ion (Li-ion) Super Phosphate (SLFP) battery system for ABB’s new hybrid cable-lay vessel.
The batteries will deliver effective energy storage for backup in cable loading and propulsion assistance, helping to cut the vessel’s fuel consumption by 27 per cent and reducing maintenance compared with traditional AC systems.
The SALT 306 CLV-design vessel, which is believed to be the largest of its type in the world, will be 140m in length with a beam of 30m. It is being built at Kleven shipyard in Norway. Delivery is expected in 2017.
The vessel’s diesel-electric propulsion system will be powered by six high-speed Caterpillar 3516 propulsion engines (with 2MW of power each) acting as gensets for three Azipod CZ980 thrusters of 1,900 kW. The thrusters, each with a thrust of more than 34 tonnes, will enable DP3 operations. Power will be converted into electricity through ABB Marine’s Onboard DC Grid, which enables variable speed running to optimise engine operations.
The 70 kWh capacity Saft battery system will be used mainly to assist the outloading of cable from the dock onto the vessel’s turntables. These operations will be primarily powered by a shore to ship cable, since the vessel’s diesel engines must be switched off when docked to meet new emissions regulations. However, should this supply be interrupted the battery can support a peak load of up to 800 kW for 10 seconds, which is sufficient to bring the turntables to a safe, controlled stop.
When at sea, the battery system can also be used for peak shaving, when there is a temporary surge in demand for propulsion power and enhanced dynamic response, when propulsion power needs to be increased rapidly.
