Alternative Fuels

Dr. Nicholas Clague shares VPS’ experience with alternative bunker fuels

Recently appointed as the Head of Sustainable Fuels, Clague provides an insight on VPS’ experience of testing the latest alternative fuels that are in use aboard vessels operating around the world.

Published

2 years ago

September 12, 2023

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Dr. Nicholas Clague, who was recently appointed as the Head of Sustainable Fuels of marine fuels testing company VPS, provides an insight on the firm’s experience of testing the latest alternative fuels that are in use aboard vessels operating around the world:

Introduction

It is well reported that 3% of global emissions are attributed to world shipping and the entire industry is now on a drive to reduce emissions to net zero close to, or by 2050. At the recent MEPC 80 conference the IMO introduced additional interim checkpoints of 20% global greenhouse gas emissions reductions compared to 2008 but striving for 30% by 2030 with a 70% (striving for 80%) reduction by 2040. On top of this the EU ETS scheme will be expanded in 2024 to include all vessels over 5000 GT transporting general cargo or passengers with the share of emissions subject to the ETS being increased from 40% in 2024 to 70% in 2025 and 100% in 2026. In addition, methane and nitrous oxide emissions will be added to the EU ETS from 2026. Offshore vessels will also be added to the scheme from 2027.

With all of these new requirements (and additional costs and complexity) for reporting emissions from vessels, operators and owners are now looking very closely at how to reduce their emissions. Some of this has been achieved from what can be done ‘today’ such as slow steaming, improving vessel design, air lubrication and reducing sulphur in fuels.

However, to meet the requirements of net -zero by 2050 and reduce the cost of paying for emissions the shipping industry is also looking at other means of decarbonisation including the use of digitalisation of onboard systems for optimal efficiency and advanced monitoring of stack/exhaust emissions. Although a lot has been done so far there is still a lot more to be done if shipping is to achieve net-zero by 2050.

One of the main ways to reduce emissions is not only to burn less fuel but to also look at alternative fuels that can help further reduce emissions and remove the need to burn fossil fuels. As an interim step some operators are looking at LNG as a fuel and installing dual fuel LNG engines on vessels.

Although LNG significantly reduces emissions – up to 23% - compared to VLSFO on a well to wake basis it is still a fossil fuel. LNG vessels also have the issue of methane slip and with methane being 25 times more potent than carbon dioxide at trapping heat in the atmosphere, other vessel operators are looking to other alternative fuels such as methanol, ammonia and bio-fuels, especially with methane emissions becoming part of the EU ETS in 2026. These fuels can provide additional emissions savings compared to conventional fuels and LNG, but also offer their own challenges.

This article provides an insight from the VPS perspective based on our experience of testing the latest alternative fuels that are in use today aboard vessels operating around the world.

VPS Experience with new Alternative Fuels

FAME (fatty acid methyl esters) or more commonly referred to as biodiesel, has been used within the road transportation sector for cars, vans and trucks for many years. The composition of FAME is dependent on the feedstocks used in the manufacturing process and can vary greatly between each batch, between each supplier and where it is purchased around the world. FAME has one big advantage in that it is a ‘drop-in’ replacement for traditional fuels and can be used at varying amounts up to 100%. For example, a B30 fuel will be a blend of 30% FAME and 70% conventional fuel.

Due to the changes in chemical structure between each FAME, its performance as a fuel can vary greatly too. Carbon chain length and degree of unsaturation can influence the cold flow properties, with the degree of unsaturation also influencing oxidation stability and oxygen content. The level of oxygen content has an influence on the energy content, which is already lower than for conventional marine fuels. As a result, VPS were able to develop a technique to fingerprint the FAME source which has proven to be a great addition to the testing used to support our customers. With the introduction of the EU ETS and with

FAME having a zero CO2 emissions factor, being able to accurately measure FAME content in fuel will be an advantage to vessel owners and operators. Several test methods already exist for determining the level of FAME in biofuels (including ASTM D7371, ASTM D7963, EN14078 and EN14103) but all have their limitations. VPS have developed a new technique which has higher precision, repeatability and reproducibility over the whole range from B0 to B100, enabling vessel owners and operators to obtain the correct emissions allowances.

FAME, due to its partially oxidised nature compared to conventional hydrocarbon-based fuels is also susceptible to bacterial growth which can lead to sludge and increased acidity, which can then lead to other problems such as blocked filters and corrosion. Again, due to it partial oxidation and some of the esters in the fuel being unsaturated, FAME can have significantly reduced oxidation stability which can cause sludge, filter blocking, darkening, acidity increase, microbial growth and rancidity which will be noticed by a rancid odour.

All that said, FAME does provide an environmental benefit from a well to wake perspective and with careful management onboard should cause no issues in its use, especially in blends with conventional fuel. So far, many of the samples tested by VPS have been single samples for single vessels with an estimated in-use total of biofuel used so far in the region of 30-40KT/month (VPS estimation) which is just a small fraction of the monthly market volume for shipping fuels. Based on data from VPS PortStats, so far in in 2023 we have tested over 300 FAME or FAME- containing bunker samples, the most of which have been available in Europe (mainly Rotterdam), but also from the US and Asia (mainly Singapore). However, based on this testing so far, we are safe to assume that FAME containing fuels are on trial and there is high scrutiny on its performance in these trials as we would expect.

This is from both crew and technical level, where in extreme cases engine components are being inspected and merited/demerited after the trial, looking for any signs of issues. This is being done at great expense to the vessel operators. Further, the top management of ship owners and operators is involved with decarbonisation high on their agendas too. This naturally results in suppliers being cautious about what is being supplied with only top quality products being offered. Will this level of diligence be maintained if biofuels were to become a main marine fuel?

To support this, of the over 300 “bunker” samples tested in 2023, only 30 vessels (approx. 10%) took biofuel more than twice. Typically, from the stem sizes taken it appears the vessel will only have this fuel onboard for around 1 week before it is consumed, further suggesting FAME biofuels are currently on trial.

Probably the biggest factor holding back the adoption of FAME into marine fuel is the price which can be as much as twice the price of VLSFO but with the introduction of the EU ETS in 2024 this cost will be off-set by the savings obtained by using FAME to increase the zero CO2 emissions allowance.

We have also seen other sources of material being used as options for fuel. HVO or hydrogenated vegetable oils is derived from waste oils from cooking and is highly processed and hydrogenated to remove any unsaturation and oxygen containing molecules like esters. As such HVO is often referred to as renewable diesel and performs in a similar way to diesel. When comparing HVO with FAME we see higher energy content, good oxidation stability, superior cold-flow properties and little or no microbial growth. This is due to the fact the HVO is hydrogenated and any partial oxidation (as found with FAME) has been removed during the hydrogenation progress. Again, as with FAME, HVO has a higher price than tradition marine fuels of similar viscosity which could restrict its usage as a marine fuel.

Cashew nut shell liquid (CNSL) and tyre pyrolysis oil (TPO) have also been suggested as marine fuels either as a ‘B100’ or in blends. CNSL is highly acidic and contains very different molecules compared to FAME which are phenolic in nature. These phenolic molecules have many uses outside the marine industry but as a fuel they could be susceptible to polymerisation under the right conditions of heat and potential prolonged storage. However, in blends with traditional fuels CNSL could be suitable as a fuel but more testing is needed to confirm its suitability. TPO is a relatively new technology and further testing is needed to prove its suitability as a marine fuel.

One fuel that is gaining a lot of attention is methanol. Unlike other fuels, it is almost entirely made up of a single molecule. It is readily available and can be manufactured from environmentally accepted sources. It also contains no sulphur and so significantly improves SOx emissions to very low levels. NOx emissions can also be reduced by up to 80% compared to conventional marine fuels. As with other alternative fuels price is a consideration for methanol especially as it has a round 2/3 the energy density of traditional fuels. Methanol is also classed as dangerous goods and has a low flash point so increased safety measures are needed when handling and shipping methanol.

VPS were recently involved in the very first bunkering of methanol in Singapore both for Bunker Quantity surveys (BQS) and Fuel Quality Testing (FQT). Following the successful bunkering operation, the fuel samples were tested and were a close match with the fuel quality that was supplied to the ship from the bunker vessel via a shore tank. Currently there are no industry specifications for the use of methanol as a fuel, but these are under development. There is a specification from IMPCA (International Methanol Producers and Consumers Association) which is being used as the benchmark specification for methanol as a marine fuel as the industry gains experience. Subsequently, VPS were involved with the bunker surveying of the same vessel in Port Said and Rotterdam as it sailed to its final destination in Denmark. VPS also undertook the analysis of the methanol fuel on all 3 occasions.

Over the next few years the number of vessels being fuelled by methanol is due to increase significantly and several new plants for producing bio-methanol are planned or under construction in support of the marine industry. Currently the vessel order book as of August 2023 shows 161 vessels on order which is about 7.6% of all vessels on order. This is up from 95 vessels on order in July 2023.

Conclusion

The maritime industry is currently working to reduce emissions to meet the IMO target of net-zero on or around 2050. There have been lots of measures adopted over the last few years to improve fuel efficiency and reduce emissions. This has included slow steaming, vessel design, air lubrication etc. However, all of these methods still involve the use of fossil fuels. So, the next step is to start using alternative fuels with significantly reduced or even zero carbon footprints. This has started with many new builds and some retrofits on vessels with dual fuel engines allowing the use of alternative fuels such as methanol.

In the future we will also start to see other fuels being used and there is a lot of current research ongoing around the use of ammonia as a zero-carbon fuel and also some consideration around the use of nuclear energy to power vessels.

VPS are also leading the way with the testing of these new alternatives fuels but are also working with vessel owners and operators to maximise their efficiency via their Maress technology and then also continuous emissions monitoring through their unique Emsys system. This gives an overall picture of energy-in via the fuel, monitoring of energy use and then quantifying the emissions from the vessel. In effect this shows how and where all the energy from the fuel has been used on the vessel.

With the EU ETS expansion in 2024 and the need to reduce emissions in shipping, VPS are leading the way in the analysis of new alternative fuels to support our customers in assisting them in meeting their emission reduction targets whilst making sure these fuels are fit for purpose. Coupled with our new and innovative digital technologies for optimised vessel operations and continuous exhaust emissions monitoring, VPS are perfectly positioned to provide a wide range of maritime decarbonisation services to the global fleet.

Photo credit: VPS
Published: 12 September, 2023

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Chinese shipbuilder delivers CMA CGM’s Singapore-flagged LNG-powered boxship

CMA CGM welcomes “CMA CGM SEINE”, the first in a four-ship series of 24,000 TEU LNG dual-fuel container ships, by Hudong-Zhonghua Shipbuilding, according to BV Marine & Offshore.

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Chinese shipbuilder delivers CMA CGM’s Singapore-flagged LNG-powered boxship

Bureau Veritas Marine & Offshore (BV) on Wednesday (16 April) announced the successful delivery of CMA CGM SEINE, a new 24,000 TEU LNG dual-fuel container ship, by Hudong-Zhonghua Shipbuilding (HZSY).

This milestone marked the completion of the first vessel in a four-ship series, with BV providing classification and BV Solutions Marine & Offshore (BVS) providing advisory services.

It is CMA CGM’s first LNG-powered vessel flying the Singaporean flag with a capacity of 24,000 TEU.

It was reported that CMA CGM planned to expand its fleet and vessel tonnage, adding more vessels under the Singapore Registry of Ships. To support the transition to more sustainable fuels, CMA CGM said it would register and bunker alternative fuel vessels under the Singapore flag.

Xavier Leclercq, Vice President of CMA Ships, said: “Today’s delivery of the ‘CMA CGM SEINE’ featuring LNG as fuel at such a large scale, will remain a major landmark in the shipping world and embodies the engagement of the CMA CGM group toward an ambitious decarbonisation path, leading the way to our industry.”

Mr. Xiufeng ZHANG, Vice General Manger of Hudong-Zhonghua shipyard, said: “CMA CGM SEINE, as the lead ship of the four 24,000-TEU LNG dual-fuel powered container ships ordered by CMA Ships from our company, stands as a new-generation maritime ‘Green Giant’ and ‘super cargo hauler’.”

The vessel integrates a dual-fuel propulsion system supported by GTT Mark III membrane-type LNG bunker tanks, with a total capacity of 18,600 cubic meters, designed to enhance both environmental performance and operational efficiency.

Measuring 399.9 meters in length and 61.3 meters in beam, the vessel has a carrying capacity of 23,876 TEU and is equipped with a WinGD W12X92DF-2.0 dual-fuel main engine, incorporating the Intelligent Control by Exhaust Recycling (iCER) system.

This configuration significantly reduces methane emissions and enables compliance with IMO Tier III emission standards when operating in "Diesel + iCER mode".

BV worked closely with the engine manufacturer and the shipyard to test the parent engine and issued the Engine International Air Pollution Prevention (EIAPP) certificate, establishing a foundation for compliance across the series. The iCER system optimises energy efficiency, achieving an Energy Efficiency Design Index (EEDI) reduction well beyond the IMO’s Tier III standards.

To address the critical sloshing challenges in large-volume LNG bunker tanks, BVS performed direct computational fluid dynamics (CFD) simulations. The verified pressure data was provided to the design unit for structural strength checks, ensuring the safety of the cargo containment system and hull support structure.

The vessel features advanced technologies to boost operational performance and energy efficiency. Equipped with the SmartEye intelligent monitoring system and the TotalCommand full-control system, it achieves automated precision control during berthing, significantly reducing berthing time and enhancing port operations.

Energy efficiency is further improved by applying variable frequency drive (VFD) technology to the engine room fans and seawater cooling pumps. Meanwhile, the WinGD Data Collection Monitoring (DCM) system offers real-time tracking and analysis for the dual-fuel main engine, supporting operational optimisation.

BV also supported the upgrade of BV certified boil-off gas (BOG) compressors by conducting sea trial tests and re-issuing product certificates, facilitating seamless system commissioning and vessel delivery.

Photo credit: Bureau Veritas Marine & Offshore
Published: 17 April, 2025

LNG Bunkering

AD Ports Group hosts first STS LNG bunkering operation at Khalifa Port

STS bunkering was part of a simultaneous operation, in which container vessel “MSC Thais” received LNG marine fuel from bunker vessel “Green Zeebrugge”, supplied by marine fuels provider Monjasa.

Published

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April 17, 2025

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AD Ports Group hosts first STS LNG bunkering operation at Khalifa Port

AD Ports Group on Wednesday (16 April) said it hosted its first ship-to-ship (STS) liquified natural gas (LNG) bunkering operation recently at its flagship deep-water Khalifa Port.

The STS bunkering was part of a simultaneous operation, in which the container vessel MSC Thais berthed at Abu Dhabi Terminals, received LNG marine fuel from the dedicated LNG bunker vessel Green Zeebrugge, supplied by marine fuels provider Monjasa.

Captain Saif Al Mheiri, CEO of Abu Dhabi Maritime and Chief Sustainability Officer at AD Ports Group, said: “By adhering to the highest safety and environmental standards, AD Ports Group and Monjasa are ensuring that shipowners have reliable access to a diversified fuel mix that supports their decarbonisation objectives.”

“AD Ports Group will continue to explore and implement forward-looking solutions that drive progress toward global sustainability goals.”

Liquified natural gas offers reduced greenhouse gas emissions and significantly less sulphur oxide, nitrogen oxide, and particulate matter emissions compared to traditional marine fuels.

AD Ports Group and Monjasa will continue expanding LNG bunkering services across the Group’s commercial ports in Abu Dhabi, including cruise vessels at Zayed Port, while offering a comprehensive fuel portfolio that includes Very Low Sulphur Fuel Oil (VLSFO), Marine Gas Oil (MGO), and High-Sulfur Fuel Oil (HSFO).

The STS operation was executed in accordance with international best practices and regulatory standards, that include LNG bunkering protocols and guidelines set by the International Maritime Organization (IMO), International Association of Ports and Harbors (IAPH), International Organization for Standardization (ISO), and Society of International Gas Tanker and Terminal Operators (SIGTTO).

With this achievement, AD Ports Group is accelerating the shift toward sustainable marine fuels, while reinforcing Abu Dhabi’s leadership in the global energy transition and advancing the UAE’s Net Zero 2050 Strategy.

Photo credit: AD Ports Group
Published: 17 April, 2025

Decarbonisation

VPS on IMO 2028: A new legislative measure for the decarbonisation of shipping

Steve Bee and Emilian Buksak break down what the newly approved IMO framework means for ship operators and how VPS can support compliance through fuel testing, emissions measurement, and strategic advisory.

Published

18 hours ago

April 17, 2025

Admin

Steve Bee, Group Marketing and Strategic Projects Director, and Emilian Buksak, Decarbonisation Advisor of marine fuels testing company VPS, on Wednesday (16 April) broke down what the newly approved IMO net-zero framework means for ship operators and how VPS can support compliance through fuel testing, emissions measurement, and strategic advisory:

On Friday 11th April 2025, the International Maritime Organization (IMO) achieved another important step towards establishing a legally binding framework to reduce greenhouse gas (GHG) emissions from ships globally, aiming for net-zero emissions by or around 2050.

The IMO Net-zero Framework is the first in the world to combine mandatory emissions limits and GHG pricing across an entire industry sector. Approved by the Marine Environment Protection Committee during its 83rd session (MEPC 83), the measures include a new fuel standard for ships and a global pricing mechanism for emissions.

These measures, set to be formally adopted in October 2025 before entry into force in 2027, will become mandatory for large ocean-going ships over 5,000 gross tonnage, which emit 85% of the total CO2 emissions from international shipping. This Net-Zero Framework will be included in a new Chapter 5 of MARPOL Annex VI.

With an estimated 900 renewable-fuel-ready vessels expected to be sailing the seas by 2030, it is felt necessary to implement global regulation to deliver renewable fuels at a commercially viable price, as current pricing for “green fuels” is 3-4 times the price of fossil fuels. Such regulations will make it possible for ships to operate on green fuels and also incentivise fuel and energy providers to invest in new production capacity.

Under the draft regulations, ships will be required to comply with:

Global fuel standard: Ships must reduce, over time, their annual greenhouse gas fuel intensity (GFI) – that is, how much GHG is emitted for each unit of energy used. This is calculated using a well-to-wake basis, meaning total emissions are measured from fuel production through to its use on board.

Global economic measure: Ships operating above GFI thresholds will need to acquire remedial units to balance their excess emissions, while those using zero or near-zero GHG fuels or technologies will be eligible for financial rewards for their lower emissions profile.

Two-tier Compliance Targets: Each ship will have to meet both a Base Target and a Direct Compliance Target for its annual GFI. Vessels that stay under the stricter Direct Compliance Target are eligible to earn surplus units, whereas those over the thresholds face a compliance deficit that must be remedied.

Data Collection & Reporting: Operators must calculate and report their attained annual GFI each calendar year, verifying it against their target annual GFI. This includes rigorous recordkeeping and submission to the IMO GFI Registry, which tracks each vessel’s emissions performance and any remedial or surplus units.

IMO Net-Zero Fund Contributions: Ships that exceed their GFI limits are required to make GHG emissions pricing contributions to the new IMO Net-Zero Fund. Collected revenues will be used to reward ships using zero/near-zero fuels, support research and technological innovation in cleaner shipping, and help ensure a just and equitable transition for the maritime sector.

Net-Zero Framework Implementation and Green Balance Mechanism

From 2028 to 2030, ships will be subject to a tiered levy linked to their well-to-wake (WtW) carbon intensity. Based on a 2008 baseline of 93.3 gCO₂eq/MJ (the industry average in 2008), operators will face no charge for fuel emissions at or below approximately 77.44 gCO₂eq/MJ, a moderate levy of $100/mtCO₂eq for emissions between 77.44 and 89.57 gCO₂eq/MJ, and a higher rate of $380/mtCO₂eq for emissions exceeding 89.57 gCO₂eq/MJ. These thresholds and levies align with the overarching goal of driving down overall carbon intensity by a minimum of 4% by 2028 and 17%for direct compliance targets—with further, more stringent reductions taking effect in subsequent years.

Surplus Units and Over-Compliance

A ship’s carbon intensity below the lower threshold (77.44 gCO₂eq/MJ) constitutes “over-compliance,” generating surplus units that can be banked or traded. Conversely, exceeding thresholds will require the purchase of remedial units to cover the compliance deficit.

Sustainable Fuel Certification Scheme (SFCS) and Fuel Lifecycle Label (FLL)

Under the new framework, all fuels must carry a Fuel Lifecycle Label (FLL), which documents their GHG intensity and other sustainability attributes on a well-to-wake basis. These values must be certified by a recognized Sustainable Fuel Certification Scheme (SFCS), ensuring accurate, transparent calculations and preventing any misrepresentation of environmental impact.

Zero or Near-Zero GHG Technologies, Fuels, and Energy Sources

Recognising the importance of incentivising advanced solutions, the regulation sets specific lifecycle emission thresholds for what qualifies as a zero or near-zero GHG (ZNZ) fuel or technology: Initial threshold (valid until 31 December 2034): ZNZ fuels must not exceed 19.0 g CO₂eq/MJ on a well-to-wake basis. Post-2035 Threshold: Starting 1 January 2035, the permissible GHG intensity tightens to no more than 14.0 g CO₂eq/MJ.

Ships adopting fuels and technologies below these thresholds can earn financial rewards through the IMO Net-Zero Fund, effectively offsetting some of the initial costs of transitioning away from conventional fossil fuels. By gradually lowering the allowable GHG intensity, the regulation encourages ongoing innovation, investment, and broader adoption of advanced, low-emission solutions across the global fleet.

Green Balance Mechanism

Central to this approach is the Green Balance Mechanism, which integrates closely with the GFI. In essence, it applies a fee on higher-intensity fossil fuels and allocates those proceeds to green fuels, balancing costs across a diverse energy mix. The greater the well-to-wake emission reductions a fuel delivers, the larger the financial allocation it receives—effectively levelling the playing field and stimulating a shift to sustainable alternatives.

VPS on IMO 2028: A new legislative measure for the decarbonisation of shipping

Disbursement of Revenues

All revenues from levies and remedial unit purchases will be directed to the IMO Net-Zero Fund, which will then distribute the funds to:

Reward low-emission ships
Support innovation, research, infrastructure, and just-transition initiatives (particularly in developing countries)
Fund training, technology transfer, and capacity-building aligned with the IMO GHG Strategy
Mitigate impacts on vulnerable States, such as Small Island Developing States (SIDS) and Least Developed Countries (LDCs)
By steadily lowering the permissible carbon intensity and introducing financial incentives for clean fuels, the new framework aims not only to reduce overall emissions but also to accelerate the maritime sector’s transition to sustainable energy solutions.

Note: The full article, including on how VPS can support compliance through fuel testing, emissions measurement, and strategic advisory, can be found here.

Photo credit: VPS
Published: 17 April, 2025