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DNV: Challenging road ahead for retrofitting to dual-fuel engines

Cost of retrofitting, including fuel storage and fuel supply system, ranges between USD 5 mil – USD 15 mil and, as a rule of thumb, this should not exceed 25% of newbuild cost of a ship to be economically viable.





Classification society DNV on Tuesday (16 May) released a Maritime Impact report on retrofitting ships with dual-fuel engines to run on alternative bunker fuels and discusses the challenges that comes with it:

The maritime industry’s decarbonization goals are multi-pronged and complex. A collaboration between DNV and engine designer MAN Energy Solutions examines how retrofitting the existing maritime fleet to dual-fuel engines capable of running on sustainable fuels can contribute to these goals.

In order for the shipping industry to achieve decarbonization that is sufficiently in line with the Paris Agreement’s goal of limiting global warming to 1.5 degrees Celsius, a full life-cycle approach – also known as a ‘well-to-wake emissions’ perspective – needs to be adopted. This forces the maritime industry to assess the emissions of shipping in a comprehensive way and moves shipowners away from the ‘tank-to-wake’ approach, where emissions reporting can be pushed upstream to the production of the fuel. At IMO’s MEPC 80 this approach will be further discussed. 

‘Well-to-wake emissions’ perspective raises standards for existing fleet

While a number of innovations are being applied to the 1,500–2,000 two-stroke and 750 four-stroke new vessels that are launched per year, the greatest challenge to achieving maritime GHG reductions is for the existing merchant fleet, which consists of approximately 55,000 ships with two-stroke engines and 30,000 ships with four-stroke engines.  

Retrofitting these existing ships to be able to run on alternative fuels like ammonia and methanol is one of the options available to the maritime industry to achieve desired reductions in emissions. However, the path ahead for retrofitting is uncertain. 

“Apart from efficiency improvements and the use of biofuels, retrofitting is another option for the existing fleet to achieving decarbonization targets,” says DNV’s Business Development Manager Christos Chryssakis. “However, there is no requirement for retrofitting so the future timeline for achieving this is not clear.” 

Biofuels not scalable for maritime industry

Currently, the most straightforward way of reducing emissions on the existing fleet is by running single-fuel engines on sustainable biofuels. Several biofuels, such as FAME and HVO, have ‘drop-in’ properties which means that they can be blended with existing fossil fuels. This is an attractive option to shipowners as it provides them with a flexible way of achieving decarbonization without having to make large capital investments.  

However, a number of key challenges remain with biofuels. Although 2022 was a record-breaking year for the consumption of biofuels, this still accounted for just 0.1% of the maritime energy mix.  

“Demand for biofuels is high from other industries, and supply is limited,” says Chryssakis. “This means that the maritime industry may struggle to acquire as much biofuel as it needs and that prices will be high. Therefore, it currently seems quite unlikely that biofuels will be a magic bullet for decarbonizing the entire existing maritime fleet.”

Retrofitting fleet provides long-term solution

With biofuels currently unscalable, converting large ships to dual-fuel engines is increasingly seen as one of the ways that the maritime industry could achieve its decarbonization targets. Retrofitting a single-fuel engine to dual-fuel enables a ship engine to run on a second sustainable fuel, as long as this is accompanied by a pilot injection of conventional fuel. While this conventional fuel will primarily be a traditional fossil fuel, sustainable biofuels or synthetic fuels can also be used.  

Dual-fuel conversions have already been applied to converting the engines of energy carriers to the fuel being carried, most frequently to LNG and LPG. This has generally resulted in around a 15–20% reduction in exhaust emissions, highlighting the key role that both of these fuels occupy as transition fuels. However, in order to achieve decarbonization targets, dual-fuel conversions need to be made for fuels which can be produced to emit close to zero ‘well-to-wake emissions’, such as green ammonia, green methanol and e-fuels.  

Larger ships most suitable for retrofitting

According to assessments by DNV and MAN ES, key retrofitting requirements for ships with two-stroke engines are electronically controlled engines, a bore size of at least 50 centimetres and a sea trial conducted after 1 January 2015. The cost of retrofitting, including the fuel storage and fuel supply system, ranges between USD 5 million and USD 15 million depending on the type of fuel and, as a rule of thumb, this should not exceed 25% of the newbuild cost of a ship to be economically viable.  

A ship should typically have a minimum newbuild cost of around USD 50 million to be suitable for retrofitting. Ships fitting these criteria include tankers above 50,000 DWT, bulkers above 160,000 DWT and containers above 7,000 TEU, among others. However, in some cases, such as for ships retrofitting to methanol, this cost can be lower. For four-stroke engines, ships with large bore sizes that conducted a sea trial 8–15 years ago appear to be the best fit for dual-fuel retrofitting. 

“Less than 10% of the existing global merchant fleet are regarded as theoretic candidates for retrofitting,” says Chryssakis. “We don’t see this happening today due to costs and uncertainties but think that this could be achieved over the next five to ten years, particularly after 2030 when regulations really start biting. However, it is difficult to predict how many of these will actually materialize.” 

IMO regulations hindering shipowners from dual-fuel retrofitting

Although several states are pushing the IMO to be even more ambitious and aim for zero emissions by 2050, some of the organization’s regulations are standing in the way of a swift, large-scale dual-fuel retrofitting of the global fleet. Of most concern to advocates of retrofitting, the IMO currently demands that a parent engine test of exactly the same electronically controlled engine type is required for a dual-fuel conversion to be NOx compliant. However, relatively new engine technologies such as methanol and ammonia are not available for all bore sizes, which means that a parent test engine is often unavailable for some desired retrofits to dual-fuel engines.  

In addition, certain older engine models, such as those running on heavy fuel oil (HFO), are not made for newbuilds anymore. This means that a newbuild parent engine is not available for testing in cases where a shipowner wishes to convert a HFO engine to dual fuel, thus making retrofitting extremely difficult under current IMO rules. Unless this regulation is amended, or new guidelines are developed, the pace of retrofitting will be significantly hindered.  

Retrofitting engines also faces practical challenges

A number of other hurdles lie on the road to large-scale retrofitting. The implementation of dual-fuel conversions is expected to be carried out by a limited number of shipyards, due to varying commercial priorities. This may lead to capacity issues if there is high demand for conversions. Furthermore, the complexity of these kinds of projects and current uncertainty around best practices leaves shipowners and yards open to potentially large cost overruns. The higher costs of alternative fuels will also increase the economic worries of shipowners. 

“The cost of fuels like ammonia and methanol presents an issue to shipowners wishing to reduce GHG emissions while also maintaining a profit,” says Chryssakis. “The price of these kinds of fuels is currently much higher than conventional marine fuels and shipowners will need to ensure that their charterers will be willing to cover the increased cost of fuels before committing large amounts of CAPEX to retrofitting projects.” 

Note: The full DNV Maritime Impact report titled ‘Challenging road ahead for retrofitting to dual-fuel engines’ can be found here


Photo credit: DNV/ MAN ES
Published: 23 May, 2023

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China Shipping & Sinopec Suppliers completes first biofuel bunkering op of passenger ship in Dalian

Firm successfully refuelled passenger ship “Chang Shan Dao” owned by Cosco Shipping Ferry with B24 bio bunker fuel on 29 November at Dalian Cruise Port.





China Shipping & Sinopec Suppliers completes first biofuel bunkering op of passenger ship in Dalian

China Shipping & Sinopec Suppliers Co., Ltd. on Wednesday (29 November) successfully refuelled passenger ship "Chang Shan Dao" owned by Cosco Shipping Ferry Co., Ltd. with B24 bio bunker fuel at the Dalian Cruise Port. 

The occasion marked the first biofuel bunkering operation for passenger ships in China. 

The B24 biofuel oil used was blended with 24% biofuel and 76% conventional low-sulphur fuel oil.

Sinopec China Shipping Fuel Supply, which is responsible for the bunkering operation, is a bunker supply firm jointly established by Sinopec Group and COSCO Shipping Group.

According to Li Zhi, Deputy Party Secretary and Deputy General Manager of China Shipping & Sinopec Suppliers Co., Ltd., the biofuel bunkering business is another step in the company's active business of the group's development strategy. 

The bunkering operation after the firm completed the first bonded biofuel bunkering operation of a domestic ship on 7 September. 

Disclaimer: The above article published by Manifold Times was sourced from China’s domestic market through a local correspondent. While considerable efforts have been taken to verify its accuracy through a professional translator and processed from sources believed to be reliable, no warranty is made regarding the accuracy, completeness and reliability of any information.

Photo credit: China Shipping & Sinopec Suppliers
Published: 8 December, 2023

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Alternative Fuels

Singapore, Tianjin to pilot and trial alternative bunker fuels following shipping corridor MoU

Singapore – Tianjin Green and Digital Shipping Corridor will serve as a valuable testbed for both countries to pilot and trial digital solutions, alternative fuels and technologies, amongst others.





Singapore, Tianjin to pilot and trial alternative bunker fuels following shipping corridor MoU

The Maritime and Port Authority of Singapore (MPA) and the People’s Republic of China’s Tianjin Municipal Transportation Commission on Wednesday (6 December) signed a memorandum of understanding (MoU) to establish the Singapore – Tianjin Green and Digital Shipping Corridor.

Mr Teo Eng Dih, Chief Executive, MPA, and Mr Wang Zhinan, Director General, Tianjin Municipal Transportation Commission, signed this MoU.

The MoU marked the first Green and Digital Shipping Corridor established between Singapore and China to support the decarbonisation, digitalisation and growth of the maritime industry between Singapore and the Bohai Region. 

The Singapore – Tianjin Green and Digital Shipping Corridor will serve as a valuable testbed for both countries to pilot and trial digital solutions, alternative bunker fuels and technologies, and facilitate talent development to support the decarbonisation and digitalisation of shipping. 

Singapore and Tianjin will work with the research community, the  institutes of higher learning, and industry stakeholders such as shipping lines, port operators, shipbuilders, classification societies, and bunker suppliers to enable more efficient port clearance through digital exchanges, encourage the offtake of zero or near-zero greenhouse gas emission fuels and adoption of new fuel technologies, spur innovation and support the growth of the maritime startups community, and facilitate manpower training and professional development.

The establishment of the Singapore – Tianjin Green and Digital Shipping Corridor reaffirms the strong commitment by Singapore and Tianjin to accelerate maritime decarbonisation and digitalisation. Singapore will also be exploring the establishment of similar collaboration with other maritime and port ecosystems within China.

Photo credit: Maritime and Port Authority of Singapore
Published: 8 December, 2023

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Report highlights routes-based action plan methodology to accelerate uptake of clean bunker fuels

NextGEN Connect-GreenVoyage2050 collaboration, which includes Singapore, emphasises the important role of regional energy hubs in enabling the inclusive adoption of clean marine fuels.





Report highlights routes-based action plan methodology to accelerate uptake of clean bunker fuels

The Maritime and Port Authority of Singapore (MPA) on Thursday (7 December) said the NextGEN Connect-Green Voyage2050 Project identified a key role for regional hubs to help connect large demand clusters and remote locations, with regional fuel supply sources, in order to enable a more inclusive and effective transition to a low-carbon maritime future. 

The project is a collaboration between Singapore, Norway and the International Maritime Organization (IMO). 

These findings were unveiled in the Lloyd’s Register Maritime Decarbonisation Hub (LR MDH) report titled Routes-based Action Plans: A Toolkit launched at the Voyage to Net-Zero Forum, which was organised by MPA, at the 28th United Nations Climate Change Conference (COP28/CMP8/CMA5) yesterday.  

The report was developed following a workshop discussion that was held from 5 to 6 October 2023 in Singapore, with the participation of 40 stakeholders representing ports and National Administrations across Asia, based on the concept of the LR MDH’s First Movers Framework for green corridors. The workshop simulated the process steps of the routes-based action plan methodology, addressing the limitations in its application in the wider Asian context. Additional engagements with stakeholders from the Pacific are envisaged to further refine the methodology. 

“One of the key findings in our report highlighted the varying pace of decarbonisation efforts across the Asian region and the need for regional coordination among governments to establish energy clusters that will serve both as demand centres and energy producing hubs” said Charles Haskell, Director at LR MDH. 

The creation of energy producing hubs includes defining a strategy that brings together demand from different countries at different developmental stages across the region to build up investment cases for implementing energy infrastructure at scale, all the while taking into consideration the economic and social benefits for local communities. 

The report also emphasised that routes-based action plans should be steered by national governments to give confidence to the industry’s infrastructure investment decisions, with development banks and regional funds needing to play a part to help tailor financing solutions to support infrastructure development. 

“If we truly want to achieve a net-zero future where no one is left behind, we cannot focus only on existing first mover initiatives. We must also study locations where the energy infrastructure is still in its infancy”, added Charles Haskell. 

Essential to driving the implementation of routes-based action plans, as highlighted in the report, is the pooling of resources and capacity building to develop the business case for building the necessary infrastructure for regional hubs that include Least Developed Countries (LDCs) and Small Island Developing States (SIDS). This will require regional coordination and collaboration involving governments and all stakeholders across the maritime supply chain.

Mr. Teo Eng Dih, Chief Executive of MPA, said: “As we steer toward a sustainable maritime future, fostering a collective and inclusive approach is imperative in the development of green corridors and the energy transition to decarbonise international shipping.”

“The NextGEN Connect-GreenVoyage2050 collaboration emphasises the important role of regional energy hubs in enabling the inclusive adoption of clean marine fuels, particularly for LDCs and SIDSs. MPA looks forward to continuing its collaboration with IMO, Ministry of Climate and Environment of Norway and LR MDH to pilot solutions to reduce GHG emissions from ships and drive innovative transformations in the maritime industry.”

Sveinung Oftedal, Chief Negotiator of the Norwegian Ministry of Climate and Environment, said: “Separate routes for emission-free ferries and ships can play an essential role in stimulating early action to adopt zero or near-zero emission technologies and fuels, and hence are an important step towards decarbonising shipping. There is currently a significant volume of maritime traffic between Asian countries, and our workshop was a great forum to discuss opportunities the decarbonisation of maritime shipping can bring and how efforts can be linked to countries’ wider energy transition.”

Jose Matheickal, IMO Director of Partnerships and Projects, said: “Supporting developing countries, including SIDS and LDCs, in their efforts to implement the 2023 IMO Strategy on the Reduction of GHG Emissions from Ships is imperative to the decarbonisation of the maritime sector. IMO is pleased to provide, through this collaboration, practical support around the development and subsequent implementation of National Action Plans and route-based actions in line with IMO’s MEPC RESOLUTION.366(79) that encourages Member States to undertake these voluntary actions to facilitate the achievement of greener shipping and reduced emissions.” 

Note: ‘Routes-based action Plans: a toolkit’ can be found here

Photo credit: Maritime and Port Authority of Singapore
Published: 8 December, 2023

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