GE’s Marine Solutions and Dalian Shipbuilding Industry (DSIC) have completed a preliminary design for the conversion of a steam turbine powered LNG carrier (LNGC) to a gas turbine-based propulsion system.
The study focuses on steam powered LNGCs that offer low fuel efficiency but are not ready to be retired from service.
The new design will feature GE’s COmbined Gas turbine, Electric and Steam (COGES) system.
“This feasibility study provides ship owners a competitive retrofit solution for 10 to 15 year-old steam-powered LNG carriers,” Brien Bolsinger, Vice President, Marine Operations at GE, commented.
“A gas turbine’s smaller footprint allows for the minimum necessary conversion work required by the shipyard. By converting to a COGES power system, the fuel efficiency of the ship will be improved by 30%,” Yingbin Ma, DSIC Deputy Technical Director, said.
“This allows ship owners to increase the charter rate and win back opportunities in a market dominated by dual-fuel diesel engines. This study achievement is based on a 138,000 cubic meter LNGC powered by a steam turbine, but it can be applied on other similar size ships,” Ma added.
Compared with two-stroke diesel engines, a gas turbine is 80% lighter and 30% smaller. Featuring reduced weight, size — and using one of the existing steam turbines — the system offers a simpler conversion that requires less dry dock time compared to a similar conversion with diesel engines.
In 2015, GE Marine and DSIC obtained Lloyd’s Register’s approval in principle (AiP) for the gas turbine-powered LNGC design.