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Wednesday, October 28, 2020 

MAN PrimeServ, MAN Energy Solutions after-sales division, has successfully converted the main engine of LPG carrier BW Gemini, operated by BW LPG, from a B&W 6G60ME-C9.2 type to an MAN B&W 6G60ME- LGIP dual-fuel type capable of operating on fuel oil and LPG.

The conversion is the first of 12 ordered by BW LPG for a series of vessels in its fleet. As gas and sea trials begin, BW Gemini becomes the first commercial vessel to be propelled by a two-stroke LPG dual-fuel engine. .

According to BW LPG's Pontus Berg, EVP, Technical and Operations, BW chose retrofits rather than newbuild. Berg said: “Retrofitting allows us to minimise our carbon footprint – the process emits up to 97% less carbon dioxide compared to a newbuilding construction. Retrofitting also means that we do not add additional tonnage that the world does not need. In addition, BW LPG’s fleet is already widely recognised amongst charterers for its efficiency, and so retrofitting 12 of its vessels to dual-fuel LPG would help to further reinforce the company’s strong reputation in this area.”

Dr Uwe Lauber, CEO MAN Energy Solutions (MAN ES), said: “The industry is moving towards a zero-carbon future and there is a strong global push towards sustainability. As we pass the 2020 sulphur cap and get closer to future IMO targets in 2030 and 2050, companies that show strong corporate commitment to sustainability will become more commercially attractive. In this context, this retrofit project represents an important milestone and case study for the future of our industry.”

Wayne Jones, MAN ES Chief Sales Officer, said: “MAN PrimeServ’s dual-fuel expertise helped BW LPG to get a clear picture of the economics involved in this ambitious retrofit project. Although it requires significant upfront investment, the returns will be positive in both financial and environmental terms, and showcase perfectly BW LPG’s commitment to action on sustainability. It also displays the adaptability of MAN Energy Solutions’ technology and how retrofitting our engines can future-proof them to handle whatever alternative fuels come to prominence in the decades ahead.”

In February 2020, the type approval/parent engine test was performed at licensee STX works in Korea, resulting in approval by all classification societies. The BW Gemini docked at Yui Lian Ship Yard in Shenzen, China in early August 2020 for conversion. Due to pandemic restrictions, the MAN PrimeServ project team collaborated in great part remotely to push the conversion forwards. On completion of sea trials, the LPG carrier will re-enter commercial trading.

With LPG as a marine fuel, the BW Gemini’s output efficiencies rise by around 10% against fuel oil, which will in turn generate notable gains in total voyage fuel-economics. According to MAN ES, this is one of several advantages that secure LPG’s position as a long-term, sustainable marine fuel. Cost-wise, LPG is considered a better option than compliant fuel oil, with high lifetime savings prospects. BW LPG’s vessels will benefit from savings due to lower fuel consumption and full dual-fuel flexibility, which guards against price sensitivity to post-2020 fuel price fluctuations. Furthermore, the ability to use LPG cargo as a supplemental fuel source reduces time and fees for fuel bunkering. Harnessing LPG propulsion translates into cleaner, more efficient engines that are cheaper to maintain. In addition, the fuel flexibility of dual-fuel engines ensures full redundancy for uninterrupted operations.

MAN PrimeServ contributed its dual-fuel technology knowhow, and with BW LPG’s experience in the gas shipping business, the initial business case could be quickly formed, and the project approved. MAN PrimeServ’s research showed that  a retrofit would be the most environmentally friendly solution. A retrofitted vessel generates 35 times less CO2-emissions compared to a newbuild vessel; and compared to 2020-compliant fuels, using LPG as a fuel would reduce SOx by 99%, CO2 by 15%, NOx by 10%, and particulate matter by 90%.

Jens Seeberg, Head of Retrofit and Upgrade, MAN PrimeServ Two-Stroke, said: “This is an exciting project that has involved many parts of MAN Energy Solutions’ worldwide organisation. Our Retrofit Department in particular has enjoyed cooperating with BW LPG, which has been very open during the entire process. As we push towards a maritime energy transition, new fuels and technology are beginning to impact the market and there is no doubt that retrofitting engines already active in the field will become more and more commonplace in time.”

BW LPG currently owns and operates 51 Very Large Gas Carriers (VLGC) and Large Gas Carriers (LGC) including two VLGC newbuildings with a total carrying capacity of 4,159,213m3. With a global presence in nine countries, BW LPG operates out of Singapore and is incorporated in Bermu

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