Using LNG as a marine fuel can cut greenhouse gas emissions by up to 23% on a well-to-wake basis compared with current oil-based alternatives, according to a new independent study commissioned by industry coalition SEA-LNG and industry body the Society for Gas as a Marine Fuel (SGMF).
The research, which was conducted by Sphera — formerly thinkstep, the company that conducted a similar study for the two organisations in 2019, — concluded that this rises to 30% when measured on a tank-to-wake basis.
The 2nd Life Cycle GHG Emission Study on the Use of LNG as Marine Fuel used the current available engine and supply chain data provided by members of the two bodies to update the earlier study. It was also reviewed again by a panel of independent academics from institutions in France, Germany, Japan and the US.
Busting methane myths
Methane emissions from the supply chains and methane released during the on-board combustion process — often referred to as methane slip — have been included in the analysis.
The study says the methane slip from high-pressure two-stroke slow-speed diesel engine is virtually zero.
It says low-pressure two-stroke slow-speed Otto cycle engines ordered today offer a 50% reduction in methane slip and describes the outlook for four-stroke medium-speed engines as "also promising".
"By 2030 engine manufacturers forecast that all LNG-fuelled engine technologies will have minimal levels of methane slip," the study said.
SEA-LNG chairman Peter Keller said: “Often based on outdated data, methane slip has become an overused argument for those wishing to justify inaction.
“The Sphera study underlines the advances being made to counteract this concern. Its analysis provides independent confirmation that, by 2030, methane slip will have been virtually eliminated as technological improvements continue.”
Accelerated uptake
SGMF chairman Samir Bailouni from Nakilat said: “It is important the industry has the best information to make often complex choices between fuels.”
Bailouni said the study provides authoritative, high-quality data on well-to-wake emissions for LNG that provide information to the International Maritime Organization for its regulatory decisions. He said SGMF will continue to give data for all candidate gaseous fuels under its remit, including ammonia and hydrogen.
“Today, the clear choice for an immediate and significant reduction in emissions is LNG,” Bailouni said, adding that SGMF expects the take-up of it as a fuel for deepsea shipping to accelerate “even as the more challenging horizon fuels are brought safely and sustainably into the mix”.
Keller said: “The facts consistently confirm that there is no deepsea alternative fuel in the short to medium term other than LNG."
He said: "LNG remains the clear starting point for a carbon-neutral future for shipping, especially as the pathway forward includes bio and synthetic products. Waiting is not an option.”
