The first electrical LNG carrier to be ordered by Maran Gas incorporating induction-based electric propulsion motor technology from GE’s Power Conversion business is expected to enter commercial service in July. The Woodside Rogers, built by one of the major Korean shipbuilders, Daewoo Shipbuilding & Marine Engineering (DSME), at its shipyard near Busan, successfully completed sea trials in late April and was handed over to Maran Gas on July 1. It is the first of seven LNG carriers incorporating the innovative GE power and propulsion technology that Maran Gas has ordered from DSME for delivery between now and 2015.
DSME and GE already had cooperated on electric propulsion systems for six vessels prior to the Woodside Rogers. Over the last 18 months, GE has won contracts to supply induction-based propulsion motor technology on no fewer than 31 LNG carriers. The Woodside Rogers will be the first of those to go into commercial service. GE’s Power Conversion business has been producing electric propulsion systems for LNG carriers for more than 10 years.
For the Woodside Rogers, GE supplied a complete system comprising of four 9.85-MVA generators, main and cargo switchboards, four transformers, two converters, two 13.26-megawatt motors and remote control. GE also provided project management, system and equipment engineering, commissioning and assistance for sea and gas trials.
According to GE, its induction-based propulsion motor technology is one of the most reliable and cost-efficient solutions for marine drive systems. The company said it has lower maintenance costs than alternative solutions, has a longer service life and offers higher environmental benefits. Now the technology of choice for LNG carriers because of its overall performance, its combination of high-power pulse width modulation (PWM) technology based on insulated gate bipolar transistors (IGBTs), together with robustly simple induction motor technology, offers important advantages to ship owners. The technology is backed by strong technical expertise and commissioning services from GE.
The electric drive system for the Woodside Rogers is powered by tri-fuel engines that run on natural gas, marine diesel gas or heavy fuel oil. The ship operator can choose the mode according to current prices of the different fuels, making the system very cost-effective. In addition, the layout of the tri-fuel engine provides a high level of redundancy, which improves the safety of the carrier avoiding off charters. Fuel consumption and emissions also are lower.
“As a result of this project, we have now developed and qualified a complete standardized product range for drives, generators and motors capable to handle a wider range of power requirements than ever,” says Paul English, marine business leader for GE’s Power Conversion business. “In the future, this will allow us to produce and deliver our product on even tighter schedules than before.”
DSME has chosen GE’s electric power systems for numerous vessels that it has built in recent years.