Bunker Fuel

DNV: Addressing methane slip in LNG-burning four-stroke Otto-cycle engines

DNV discusses LNG and methane slip in a Maritime Impact report and elaborates on its role in several projects aiming to minimize methane slip.

Published

1 year ago

December 6, 2023

Admin

DNV: Addressing methane slip in LNG-burning four-stroke Otto-cycle engines

Classification society DNV on Monday (27 November) released a Maritime Impact report discussing LNG and methane slip and DNV’s role in several initiatives to minimize it. The following is an excerpt from the article:

LNG offers many benefits as a transitional ship fuel. However, certain engine types have been found to release significant amounts of unburnt methane, a powerful climate gas. DNV is involved in various projects aiming to minimize methane slip.

Methane, the main component of natural gas and LNG, has a global warming potential (GWP) 29.8 times that of carbon dioxide (CO2) over a 100-year timeframe, according to the Intergovernmental Panel on Climate Change (2021). Preventing methane from escaping anywhere along its supply chain is therefore crucial as the world tries to contain the causes of climate change.

New EU regulations increase pressure to reduce methane slip

LNG-fuelled four-stroke Otto-cycle engines, which are often used for gensets on board passenger ships, have been found to release significant amounts of unburnt methane, leading to CO2-equivalent emission values that compromise what is achieved through other carbon reduction efforts.

The shipping sector will be incorporated into the EU’s Emissions Trading System (ETS) from 2024. This expansion will encompass methane and nitrous oxide emissions starting in 2026. Additionally, the FuelEU Maritime requirements for the GHG intensity of energy utilized on board will come into effect in 2025. Consequently, the shipping industry is keenly interested in addressing methane slip issues.

LNG's long-term zero emissions potential hinges on methane slip reduction

“Many think of LNG as a transitional fuel only, but it can also be much more than this,” says Hans Eivind Siewers, Segment Director Passenger Ships and RoRo at DNV. “But in order for this fuel to take passenger ships all the way to zero emissions with bio LNG and e-LNG, it is of major importance that we succeed in reducing methane slip.”

Fabian Kock, Head of Section Environmental Technologies Air at DNV, agrees: “Methane slip is indeed a critical issue for addressing climate change. DNV is actively working with many stakeholders and regulators to find pragmatic solutions to overcome this challenge. In particular we are happy to work closely together with the engine designers to find technical solutions which are safe and feasible to be installed on board of ships.”

GREEN RAY industry initiative addresses methane slip

One major initiative dedicated to reducing methane slip from LNG ship engines is the EU HORIZON project GREEN RAY (new GeneRation marinE ENgines and Retrofit solutions to Achieve methane abatement flexibilitY). Launched in June 2022 under the leadership of the VTT Technical Research Centre of Finland, it aims to establish sound scientific data about methane slip from four-stroke LNG-fuelled engines by conducting on-board exhaust gas measurements, and to promote the development of methane abatement technologies.

The project consortium includes the Finnish Meteorological Institute, Shell Global Solutions, Wärtsilä, MSC, CMA Ships, Chantiers de l’Atlantique, DNV and a number of other stakeholders. A report will summarize the findings after the project ends in 2027.

Focus on engine optimization and exhaust gas aftertreatment

The engine manufacturer Wärtsilä has been conducting research and development on engine modifications to radically reduce methane slip, including efforts to optimize engine design and control. VTT researchers studied methane emissions from two Wärtsilä 31DF engines on the AURORA BOTNIA. One used standard configuration, the other tested new combustion. Results show reduced methane emissions and potential for overall emission cuts for the modified engine.

Shell is developing methane absorption and catalytic conversion technologies for exhaust gas aftertreatment. The role of DNV in the GREEN RAY project will be to witness exhaust gas measurements, verify piping and materials as well as installation, and develop and update its class rules related to emission reduction with the option to introduce a dedicated class notation. Furthermore, DNV will provide know-how and review solution proposals.

MAN takes a two-pronged approach

There are similar initiatives beyond the GREEN RAY project, as well. MAN Energy Solutions SE has been exploring ways to optimize its own engine technology to minimize methane slip. The company’s R&D into engine optimization is well advanced and integrated into every new four-stroke ship engine MAN delivers, says Dr Mathias Moser, Head of Technology and Exhaust Aftertreatment at MAN Energy Solutions SE.

“We optimize the mechanical components to minimize crevice volumes in the cylinder and we adapt the compression ratio towards improved combustion,” he explains. “Furthermore, we fine-tune engine control parameters such as injection timing, pilot-fuel amount, supercharge pressure, ignition timing, valve timing and combustion temperature. Most of these improvements can be implemented as retrofits to existing engines, as well. These engine-based measures alone can reduce methane emissions significantly so the updated engines will comply with future, tighter restrictions.”

T2 Fer Cru 507 Methane oxidation catalyst tcm71 250444 1

Note: DNV’s full Maritime Impact report on ‘Addressing methane slip in LNG-burning four-stroke Otto-cycle engines’ can be found here.

Photo credit: MAN Energy Solutions, Avenir LNG
Published: 6 December, 2023

Up Next

KPI OceanConnect, Titan, and SFL join forces on milestone LNG bunkering operation

Don't Miss

Norwegian maritime startup ESG-NRG launches digital tool ETS Manager

Business

SMW 2025: MPA and Dalian Maritime University to partner on joint maritime training

Both signed a MoU to enhance talent development and academic exchange between Singapore and China, focusing on maritime digitalisation and decarbonisation and covering areas such as clean energy.

Published

7 hours ago

March 28, 2025

Admin

SMW 2025: MPA and Dalian Maritime University to partner on joint maritime training

The Maritime and Port Authority of Singapore (MPA) and Dalian Maritime University (DMU) on Friday (28 March) said they have renewed their Memorandum of Understanding (MoU) to enhance talent development and academic exchange between Singapore and China in the maritime sector.

The MoU renewal was signed by MPA Chief Executive, Mr Teo Eng Dih, and Professor Shan Hongjun, President of DMU. This renewal builds on the successful collaboration established since 2021, and further strengthens talent development and knowledge exchange between both maritime ecosystems.

As part of the MOU, MPA and DMU will continue to engage in faculty exchanges, study visits and student exchanges in Singapore and Dalian, and joint maritime training and research programmes. Trainers from MPA, including subject matter experts and adjunct trainers, will contribute to courses, events and knowledge sharing.

The collaboration will focus on digitalisation and decarbonisation, covering areas such as clean energy and sustainable practices in the maritime sector, digital transformation of maritime operations, environmental management, maritime safety, navigational technologies, and port management and smart technologies.

DMU is home to world-class facilities, including two ocean-going training vessels and state-of-the-art research centre. A leader in autonomous ship technology and innovation in smart and sustainable shipping, the university has recently launched its 3rd ocean-going new generation autonomous training vessel.

Mr Teo Eng Dih, Chief Executive, MPA, said, “The renewal of this MOU reflects the strong partnership between MPA and DMU. As the maritime industry evolves, our collaboration in maritime education and training is more crucial than ever in preparing the next generation of maritime professionals. This agreement will enhance maritime talent development and knowledge sharing between Singapore and China, fostering innovation and sustainability in the maritime sector.”

Photo credit: Maritime and Port Authority of Singapore
Published: 28 March, 2025

Alternative Fuels

SMW 2025: Geospatial tools to be explored for port operations including bunkering

MPA and partners will explore the use of geospatial tools to develop solutions to improve safety and efficiency of port operations, such as bunkering of alternative fuels and vessel navigation.

Published

7 hours ago

March 28, 2025

Admin

SMW 2025: Geospatial tools to be explored for port operations including bunkering

The Maritime and Port Authority of Singapore (MPA) on Wednesday (26 March) signed a memorandum of understanding (MoU) with several partners to promote knowledge-sharing initiatives and explore geospatial technologies to address real-world challenges in the republic.

Partners will explore the use of geospatial tools to develop solutions to strengthen preparedness, monitor sea level rise, and improve the safety and efficiency of port operations, such as vessel navigation, marine services and the bunkering of alternative fuels.

MPA signed a three-year MOU with Jurong Port, Singapore Cruise Centre Private Limited, Esri Singapore, Hexagon’s Safety Infrastructure and Geospatial Division, Nika, Technology Centre for Offshore and Marine, Singapore (TCOMS), A*STAR Institute of High Performance Computing (A*STAR IHPC) and the Centre of Excellence in Modelling and Simulation for Next Generation Ports (C4NGP) in the College of Design and Engineering of the National University of Singapore (NUS).

Geospatial tools use location-based data such as satellite images, traffic and weather data, and sensor readings from buoys and on land to create 2D and 3D visual insights.

These can help stakeholders monitor real-time conditions, manage risks, and plan operations more effectively by improving risk management and decision-making, and enhancing operational planning for improved safety and efficiency.

MPA also signed a three-year MOU with NUS to develop a skilled maritime geospatial workforce.

Under this partnership, MPA and NUS will explore the development of maritime geospatial courses for NUS undergraduate and post-graduate geography students, and a professional certification programme for mid-career professionals.

The maritime geospatial programmes will cover skills in 2D and 3D mapping, geospatial analytics, and advanced environmental and operations modelling. This will build a pipeline of talent equipped with the skills and knowledge to drive maritime geospatial innovation in the industry and government.

Photo credit: Maritime and Port Authority of Singapore
Published: 28 March, 2025

Biofuel

Monjasa and NYK complete first-ever biofuel bunkering operation in Panama

Monjasa delivered a total of 900 mt of B30 biofuel, using tanker “Monjasa Thunder”, to NYK-operated vessel “Hestia Leader” at Port of Cristobal, marking the first ISCC-certified biofuels supply in Panama.

Published

7 hours ago

March 28, 2025

Admin

Monjasa and NYK complete first-ever biofuel bunkering operation in Panama

Marine fuels supplier Monjasa on Thursday (27 March) said it delivered a total of 900 metric tonnes (mt) of B30 biofuel to NYK-operated vessel Hestia Leader in the Port of Cristobal, Panama on 2 February.

This ship-to-ship operation was performed by the 19,991 dwt Monjasa Thunder and marked the first ISCC-certified biofuels supply in Panama and the establishment of a scalable 2nd generation marine biofuels supply chain. This setup is capable of supplying a total of 5,000-7,000 mt monthly.

On 24 March 2025, the Panama Canal Authority announced the introduction of a NetZero Slot designed to support and reward shipowners and operators on their journey towards decarbonisation.

General Manager Latin America, Jonas Bruslund, said: “The introduction of biofuels in Panama has progressed slower than in major bunkering hubs like Singapore or Rotterdam, mainly due to lack of local feedstock and customer commitments.”

“However, we have now developed a viable strategy with a longstanding business partner to ship biofuels products from Europe for the benefit of shipowners operating in the Panama Canal area.”

“The Panama Canal has a strong agenda to promote low-carbon fuels and higher energy efficiency and we are pleased to challenge the status quo and actively support these efforts.”

Monjasa established its local maritime logistics in 2015 and today manages seven vessels across the Atlantic and Pacific areas of the Panama Canal.

In the Americas, Monjasa has already established biofuels partnerships across the port of Callao in Peru and in Cartagena, Colombia.

As an ISCC-certified partner, Monjasa allows all involved parties to trace feedstock used to produce biofuels from the point of origin to the end consumer. On this first supply in Panama, the B30 product consisted of 30% Fatty Acid Methyl Ester (FAME) and 70% Very Low Sulphur Fuel Oil (VLSFO).

Monjasa still awaits the shift away from sporadic biofuels inquiries to a broader pick-up in demand. Until then, Monjasa aims to continue establishing a string of global biofuels supply locations to support the shipping industry in meeting IMO’s 2050 climate change commitments.

Photo credit: Monjasa
Published: 28 March, 2025