Classification society DNV on Thursday (20 March) published a Technical and Regulatory News highlighting the benefits of direct methane emissions measurements, which has the the potential to improve a ship’s reported GHG emissions:

Methane slip, as based on standard factors, can account for up to 24% of GHG emissions from an LNG-fuelled vessel. As an alternative to using standard factors for the reporting of CO2 equivalents, direct methane emissions monitoring has the potential to positively impact a ship’s reported carbon footprint. Discover more in this news about how to improve your reported GHG emissions.

Background

LNG has become an increasingly vital fuel in the global maritime fuel mix. However, achieving complete combustion of LNG in current engines remains challenging. This incomplete combustion leads to the release of unburnt fuel, primarily methane, into the atmosphere – a phenomenon known as methane slip. Given that methane has over 25 times the global warming potential (GWP) of CO2, methane slip emissions significantly impact a vessel’s greenhouse gas (GHG) footprint.

Regulatory framework

EU regulations and IMO guidelines account for methane slip from LNG-fuelled engines by using standard factors. Table 1 shows the LNG standard correction factors as % of the mass of the fuel for three different engine types:

Considering the GWP of methane is 28 times that of CO2, these standard factors can result in methane slip contributing to up to 24% of the reported GHG emissions, which is accounted for in terms of CO2 equivalent.

Regulations allow for deviations from predefined standard factors if real figures can be certified by a direct emissions measurement.

In January 2025, a dedicated IMO Correspondence Group took a significant step towards standardizing the quantification of methane slip through direct measurement. They submitted their report for MEPC 83, which includes proposed draft guidelines for test bed and onboard measurements of methane emissions from marine diesel engines. These guidelines represent the first essential tool for reliably verifying methane slip measurements.

DNV expects that the draft guidelines will be adopted by the IMO at MEPC 83 ending on 11 April 2025.

Methane slip measurement support from DNV

DNV’s accredited emissions laboratory, Envilab, is staffed with highly qualified professionals offering to accurately identify your methane slip values. Our methane measurement service complies with the new IMO draft guidelines and can be performed on test beds or on-board ships. Results are documented in an official emissions report, certifying reduced methane slip factors for verification.

Benefits of methane slip measurements

Direct measurements of methane emissions offer significant advantages over standardized factors, especially when the standardized methane slip factor seems excessively high for a specific engine type or when methane abatement technologies are used to further treat exhaust emissions.

Although the total amount of methane slip might initially seem minor, it significantly impacts reported GHG emissions. Methane’s GWP over a 100-year timescale is 28 times higher than CO2, meaning even minor adjustments in methane emissions can substantially affect the reported CO2 equivalent. Figure 1 illustrates the potential impact of methane slip reduction for a propulsion engine, verified through direct measurements. The resulting benefits for carbon balance are comparable to other energy-saving measures.

Furthermore, the reported GHG equivalent emissions caused by methane can be almost entirely mitigated by applying methane catalysts. The reduction potential of methane catalysts can only be accurately verified through measurements of methane slip.

Recommendations

Consider methane slip measurements as part of your strategy:

It is recommended to evaluate whether the standard methane slip factors significantly differ from those of your installed engine. Collaborate with the engine designer to assess potential improvements for reducing methane slip.

Any deviations from the standard factors can be verified by measuring methane slip on board your ship. DNV provides support for these measurements.

Photo credit: william william on Unsplash
Published: 24 March, 2025

Energy company Gasum on Wednesday (19 March) announced its delivery of liquified natural gas (LNG) to a car carrier during a simultaneous bunkering and cargo operation (SIMOPS) at the Port of Gothenburg, Sweden. 

The company said it was the first ever LNG delivery to Höegh Sunlight at the Logent Car Terminal on 10 March 2025.

Gasum’s LNG bunker vessel Coralius made its 920th LNG delivery to Höegh Sunlight, a brand new Pure Car and Truck Carrier (PCTC), with a capacity of 9100 CEU, during a ship-to-ship (STS) bunkering operation. 

The company did not specify the amount of LNG supplied to the vessel.

The delivery was a collaboration between Gasum, Glander International, Höegh Autoliners, the Port of Gothenburg and Sirius Agency. 

Photo credit: Gasum
Published: 20 March, 2025

The Oman Maritime, Ports and Energy Forum (OMPEF) is set to showcase the Sultanate of Oman’s expanding capabilities in ports, energy, shipping, maritime logistics, and bunkering. 

The event is designed to highlight how Oman’s maritime-related industries are capitalising on shifting global trade flows, driving innovation, and positioning the region at the forefront of the energy transition.

The event will be held from 28 to 30 April at Muscat in Oman. 

Event Programme Highlights

According to the OMPEF Programme, delegates can look forward to:

• Keynotes and Panel Discussions: Government and industry leaders share insights on new market prospects, regulatory developments, and collaborative strategies to strengthen Oman’s role in global maritime trade.
• Technological Advancements: Focus on digitisation and operational efficiencies, including automation, data analytics, and AI-driven solutions to reduce costs and enhance competitiveness.
• Bunkering and Energy Transition: Experts explore the latest in conventional and alternative fuels, including LNG and biofuels, along with updates on Oman’s bunkering infrastructure.
• Infrastructure and Port Developments: Updates on expansions and modernisation efforts at key Omani ports - enabling higher throughput, improved logistics, and more seamless supply chain connections.
• Networking Opportunities: Exclusive gatherings designed to foster international partnerships, expand professional networks, and encourage the exchange of innovative ideas.

Note: Additional information or programme updates can be found at the official event website here or email [email protected].

Photo credit: ship.energy
Published: 20 March, 2025