ABB Delivers Vessel with First Onboard DC Grid System
ABB announced that the first vessel to feature Onboard DC (direct current) Grid has been delivered to Norwegian offshore owner Myklebusthaug Offshore by Kleven Yard.
The Platform Supply Vessel (PSV) “Dina Star,” designed by Norwegian company Marin Teknikk, is 93 meter long with deadweight tonnage (DWT) approximately 5000 ton and will serve as a multipurpose oil field supply and construction vessel in the North Sea. ABB supplied the Onboard DC Grid system, including all power, propulsion, automation and advisory systems. ABB said the system will allow the ship to operate at the highest energy efficiency level to minimize emissions.
In traditional electrical propulsion vessels, multiple DC connections are made to thrusters and propulsion drives from an alternating current (AC) circuit, accounting for more than 80% of electrical power consumption. ABB's Onboard DC Grid represents a breakthrough for the maritime industry in optimized propulsion by distributing power through a single DC circuit providing significant power savings.
ABB unveiled the Onboard DC Grid concept in mid-2011, with a pilot project contract following six months later. The concept has attracted high levels of interest from ship owners operating a wide range of ship types, namely offshore, tugs, jack ups, ferries and yachts. For the time being the DC Grid is available in low voltage with an installed power up to approximately 20 megawatt. By distributing electricity in DC, the system allows the operation of the generators at a variable speed and consequently at the optimal specific fuel consumption. This is particularly beneficial for offshore vessels operating in Dynamic Positioning (DP) mode, where average power demand is low.
The DC Grid configuration also means bulky AC switchboards and propulsion transformers are no longer required. This, combined with greater system lay-out flexibility, increases the available space and deadweight for cargo.