SEA-LNG: Methane slip for all engine technologies to be eliminated within decade

The industry coalition SEA-LNG has underlined the significant progress being made to eradicate methane slip as the uptake of the liquefied natural gas (LNG) pathway accelerates.

Today, 2-stroke diesel cycle engines account for approximately 75% of the LNG-fueled vessel order book. These engines have effectively eliminated slip already.

For low-pressure engine technologies where methane slip remains a challenge, manufacturers have already cut the levels of slip from low-pressure 4-stroke engines by more than 85% over the past 25 years.

SEA-LNG noted that methane slip has been eradicated for the similar LNG dual-fuel engine technologies used in the heavy-duty vehicle sector. The science is clear, the technologies exist, and ongoing engineering could soon solve the problem, as highlighted.

According to SEA-LNG, with continued collaborative efforts across the value chain, methane slip will be eliminated for all engine technologies within this decade.

There is a growing momentum for LNG as a marine fuel.

According to the latest research published by classification society ABS, LNG is currently the most developed alternative fuel in terms of bunkering infrastructure and its usage is expected to increase significantly. LNG use is relatively stable, starting at 9% in 2023 and experiencing an increase to 14% by 2028 before stabilizing around 13% by 2040.

Clarksons’ data shows that 109 LNG dual fuel vessels have been ordered in 2024 up to June. There are now more than 550 LNG-fueled vessels in operation, a number expected to double by 2027.

“We congratulate the efforts and initiatives such as the Methane Abatement in Maritime Innovation Initiative (MAMII) and the GREEN RAY project. As LNG continues to gain widespread recognition as the current practical and realistic alternative fuel pathway, it is reassuring to see growing evidence that the challenge of methane slip will be eliminated within this decade,” Peter Keller, Chairman of SEA-LNG, said.

As part of the EU-funded GREEN RAY project, Wärtsilä has piloted technologies on the Aurora Botnia RoPax ferry resulting in further methane slip reductions of up to 56% in one of its most popular, and already emission-efficient, dual-fuel low-pressure four-stroke engines.

Meanwhile, MAMII has begun a process of piloting exhaust stack methane abatement technologies, including from Green Instruments and Everimpact. It has also called for and is working with regulators on a methane measurement, certification and validation protocol.

“There is universal agreement that the science is understood, and we have the necessary tools and technology to abate methane emissions, it is the final elements of the engineering that are being worked on,” Keller added.

“This, in combination with the option to transition to net zero emissions through bio-methane and e-methane, provides ship owners and operators with the confidence that vessels ordered today are future-proofed for the next 25 – 30 years. This cannot be said for any other alternative fuel right now.”

• 185 global ports can bunker LNG
• SEA-LNG: LNG has half the lifetime cost of methanol and ammonia
• LNG as marine fuel: A risky or future-proof investment?