The first electrically propelled liquefied natural gas (LNG) carriers, each at 174,000 cubic meters, to be built in China will incorporate power and propulsion systems developed and built by GE’s Power Conversion business.
Hudong-Zhonghua Shipbuilding Group, part of the China State Shipbuilding Corporation, signed contracts with GE for the supply of power and propulsion systems for six LNG carriers that it will build in its shipyard in Shanghai for major Asian shipping companies, including China Shipping Group and Sinopec Kantons Holdings. The carriers, which will be used for transporting LNG from Australia to China, will be delivered between April 2016 and November 2017.
The decision to use dual-fuel diesel-electric (DFDE) propulsion for the new LNG carriers marks a turning point in propulsion systems for large LNG ships built in China where until now either steam turbines or two-stroke engine technology has been the norm. Electrical propulsion technology is more efficient and presents less of a burden on the environment due to lower fuel consumption and emissions. DFDE drive systems also are more compact than alternatives, enabling carriers to hold more cargo.
GE will supply induction motors with PWM propulsion technology driven by electricity generated from high-efficiency “dual-fuel” engines that can run on natural gas, marine diesel gas or heavy fuel oil. The combination of dual-fuel engines, which can use boil-off gas from the carrier’s LNG tanks, and GE’s electrical variable-speed drives, presents a proven solution that is now commonly used on LNG carriers.
For each vessel, GE will supply two propulsion systems comprising of generators, main and cargo switchboards, transformers, MV7000 converters, motors and remote control. GE is responsible for design, engineering, commissioning, training and assistance for sea and gas trials.