Design acceptance to convert twelve gas carriers to run on LPG

For the first time, very large gas carriers (VLGCs) will be converted to dual-fuel LPG engines now that the project has received flag acceptance. The twelve ships are owned by BW LPG.

The project is being carried out by BW LPG, the Isle of Man Ship Registry, Wärtsilä Gas Solutions, MAN Energy Solutions, and DNV GL. After the conversion the vessels will also receive the newly developed DNV GL class notation “GF LPG”. BW LPG first announced the project in August 2018. The flag state acceptance of the design by the Isle of Man means that the project has been demonstrated to have an equivalent level of safety to methane as a ship fuel under the IGC Code 2016.

‘This acceptance is the result of all of the partners bringing their exceptional competence and experience to come up with a safe and feasible solution for this innovative project,’ says Knut Ørbeck-Nilssen, CEO of DNV GL – Maritime. ‘In addition, the knowledge we have gained from working on the project has resulted in us being able to release a new dedicated LPG notation, which we hope will spur the further interest and uptake of LPG as a ship fuel.’

LPG fuel deck tanks

The vessels will be fitted with two additional LPG cargo/fuel deck tanks in cargo area, so as not to compromise the cargo capacity onboard and a high-pressure liquid fuel system for the modified MAN Energy Solutions two stroke engines. Using LPG as a ship fuel results in substantial lower emissions to air, virtually eliminating sulphur emissions as well as reducing particulate matter and black carbon emissions.

Used with a two-stroke engine, LPG can also significantly cut NOx emissions and reduce greenhouse gas emissions. Retrofitting has the added benefit of extending the lifespan of the vessel, significantly reducing the overall carbon footprint compared to a newbuilding.

BW LPG plans to begin the conversions of the first two vessels, BW Leo and BW Gemini, this summer with completion scheduled for late summer 2020. The other vessels are targeted for conversion at their next drydocking period.

Image caption: VLGC BW Leo (by BW LPG).

Author: Mariska Buitendijk

Mariska Buitendijk is one of SWZ|Maritime's journalists as well as the magazine's copy editor.