An independent study has revealed that the use of LNG as marine fuel could achieve the reduction of greenhouse gas (GHG) of up to 21% when compared with current oil-based marine fuels.

SEA\LNG, a UK-registered not for profit collaborative industry foundation, said on Thursday that the study also confirms that emissions of other local pollutants, such as SOx, NOx, and particulate matter, were close to zero when using LNG compared with current conventional oil-based marine fuels.

The study, commissioned by SEA\LNG and non-government agency Society for Gas as a Marine Fuel (SGMF), was conducted by data and consultancy provider Thinkstep according to ISO standards.

SEA\LNG chairman Peter Keller said: “The Life Cycle GHG Emission Study is a long-awaited piece of the ‘LNG as a marine fuel’ puzzle. It not only confirms what we already knew in terms of LNG’s immediate impact on air quality, human health, and its cleanliness but clearly highlights the genuine, substantiated GHG benefits of using today’s marine engines capable of burning natural gas.

“[…] it is clear that LNG is the most environmentally-friendly marine fuel that is readily available and safe, both today and in the foreseeable future.”

On an engine technology basis, the absolute Well-to-Wake (WtW) emissions reduction benefits for LNG-fuelled engines compared with HFO fuelled ships today are between 14% to 21% for 2-stroke slow speed engines and between 7% to 15% for 4-stroke medium speed engines.

Also, 72% of the marine fuel consumed today is by 2-stroke engines with a further 18% used by 4-stroke medium speed engines.

Study partner Chad Verret, SGMF board chairman, added: “LNG is safe to use, fully compliant and readily available as a marine transport fuel. Standards, guidelines, and operational protocols are all in place to ensure that the safe way is the only way when using gas as a marine fuel.

“LNG meets and exceeds all current and 2020 marine fuel compliance requirements for content and emissions, local and GHG. With the world LNG Bunker Vessel fleet doubling in the next 18 months and those vessels being deployed at major bunkering hubs, LNG as a ship fuel is rapidly becoming readily available.”

Additionally, bioLNG and Synthetic LNG – both fully interchangeable with LNG derived from fossil feedstock – offer the potential for significant additional GHG emissions reductions. According to the study, a blend of 20% bioLNG as a drop-in fuel can reduce GHG emissions by a further 13% when compared to 100% fossil fuel LNG.

It is worth noting that the report looked at all major marine engines with help from quality data provided by equipment manufacturers including Caterpillar MaK, Caterpillar, GE, MAN, Rolls Royce, Wärtsilä, and Winterthur Gas & Diesel as well as from ExxonMobil, Shell, and Total from the supply side.