Sustainable shipping

in a changing climate …

With The European Green Deal, introduced in late 2019 and further matured in 2020, the EU Commission planted the seed for the transformation of the Union into a modern, resource-efficient and competitive economy, eliminating net emissions of greenhouse gases by 2050 and decoupling economic growth from resource use. In September 2020, EC President Ursula von der Leyen proposed to raise the level of EU ambition and reduce GHG emissions by 55% by 2030.

A revision of the Energy Taxation Directive along with a proposal to extend European emissions trading system to the maritime sector are amongst the proposed measures and initiatives that are planned for publication in 2021 and that address the call for the price of transport to reflect the impact it has on the environment, leaving no doubt that the EU wants to be leading the way in creating a green and inclusive economy.

The Belgian Shipowners welcomed these initiatives designed to turn climate and environmental challenges into opportunities. Earlier investments in research and development of sustainable alternative power systems and fuels such as green methanol, hydrogen and hydrogen carriers are starting to deliver tangible results.

Determined to stay on track to deploy zero emission vessels as soon as possible this century, continuous and swift adaptation to new challenges and unwavering perseverance to overcome remaining hurdles will remain key.

Time-lapse construction work Hydrogen refuelling station.

Not only will ships need to be adequately equipped to use the fuels of the future, but these fuels will also need to be made available in ports worldwide, in the quantities and at the quality levels required for the shipping industry.

Along with the rapidly changing regulatory landscape, cooperation with other stakeholders such as engine builders, fuel producers and the entire supply chain will prove to be essential to meet IMO’s initial strategy and to stay aligned with the Paris agreement.


working together with all maritime transport stakeholders …

The European Sustainable Shipping Forum (ESSF) provides a platform for structural dialogue, exchange of technical knowledge and cooperation between the EU Commission, Member States’ authorities and maritime transport stakeholders. In 2020, RBSA participated in several ESSF meetings, with the aim of further promoting environmentally sustainable initiatives such as the ongoing research on alternative fuels and the increase of energy-efficient maritime transport in Europe as part of the overall supply chain.

Together with the Waterborne Technology Platform and other stakeholders from the maritime cluster such as the shipyards, shipbuilders and other Members of Sea Europe, RBSA accepted a Partnership in the STEERER project in 2019 (Structuring Towards Zero Emission Waterborne Transport). This project ran over the entire year 2020 with the aim of finalization in 2021. STEERER concentrates on selecting the most promising solutions per segment of the waterborne transport sector, tackling barriers to their further development and on the deployment of innovation.

Broader expertise was involved through the establishment of the Green Shipping Expert Group, under the supervision of the Scientific Committee. A communication campaign to raise broader awareness of the waterborne transport sector and its commitment towards zero-emission transport was developed as well and it will be launched in 2021.

RBSA has contributed to the STEERER project through the mapping of relevant projects in order to get a view on the state-of-play regarding the development and uptake of new energy-efficient technologies and alternative fuels. For each technology, related projects were listed and analysed:

technology has
been applied?

What is the TRL
of the applied

Who are the

When will the
project be

In which part of the
world is the project
taking place?


The analysis shows which technologies the different segments within the maritime industry are focussing on.

The work done within the STEERER project fits seamlessly into the ongoing work of our Maritime Industry Decarbonisation Council (MIDC) with cross-pollination as a result. Since the COVID pandemic prevented us from having our quarterly face-to-face round tables, the sessions continued virtually. Based on the analysis done within the STEERER project and the focus of interest from the members, one or two topics were chosen per session and project partners were invited to highlight the findings of their projects as well as the barriers that were still being faced. As is customary, the goal of each session was to tackle the topic from a 360° point of view, so that each member had the chance to learn from the session and/or enlighten the other participants with their specific knowledge.


supporting ambitious policies & initiatives in the EU …

Over the course of 2020, many ideas and initiatives were discussed and prepared to decarbonise and regulate the shipping industry by the EU regulators. The Belgian Shipowners welcomed many of these initiatives, and actively participated to the consultation process.

Please click on the icon of your interest

The EU Monitoring Reporting and Verification (MRV)
The EU Hydrogen Strategy
European Emission Trading System (ETS)
The Fuel EU maritime initiative
Technical and operational measures for more efficient and cleaner maritime transport

and at the international level …

On 13 April 2018, IMO adopted a strategy to reduce GHG emissions from shipping. By 2023, IMO Member States will have to decide how shipping will improve its energy efficiency (expressed in g.CO2/ by 40% compared to 2008 levels, with the final aim of a 50% reduction in GHG emissions by 2050 compared to 2008 levels, with a strong emphasis on zero emissions by the end of the century. This will ultimately align emissions from shipping with the Paris Agreement.
Fourth IMO Greenhouse Gas Study, IMO, 2020

According to the IMO 4th GHG study, GHG emissions from shipping rose by 10% between 2012 and 2018, from 977 million tonnes to 1,076 million tonnes. Of particular concern is the high level of ‘short-lived’ pollutants such as black carbon and methane, which rose by 12% and 150%, respectively, over the same period. The significant rise in methane emissions is due to the increased use of LNG, which reduces CO2 and NOX emissions and produces no SOX or PM emissions. It however emits high levels of methane compared to heavy fuel oil (HFO).

The study also showed that the carbon intensity of shipping operations improved over this period by about 11%. These efficiency gains were however outstripped by growth in activity. By 2050, emissions are projected to have increased by up to 50% relative to 2018, despite further efficiency gains, as continued growth of transport demand is expected.

For the industry to stay on track, further work on short- and medium-term measures was undertaken over the past year at the IMO. Without question, more needs to be done, as the COVID 19 health crisis has also impacted the on-going work at IMO.

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Measures under development

If short-term measures are to become effective by 2023, a solid agreement on the work already carried out in 2020 will need to be found at MEPC 76 (June 2021). During the intersessional working group on GHG and MEPC in 2020, the work focussed on the joint development of two mandatory goal-based measures, a technical measure, the EEXI (Energy efficiency index for existing ships), and an operational measure, the CII (Carbon Intensity Indicator). This EEXI / CII package will combine technical energy efficiency with operational carbon intensity.

The EEXI will cover all aspects related to the design of the existing ships (cf. EEDI for new builds) while the CII will measure the fleet’s operational carbon intensity. It is the intention of the IMO parties to agree on this package by adoption of the necessary MARPOL amendments and approval of Impact assessments. However, many specifics of the proposed policy option (and therefore the level of compliance) remain unclear. More clarification is expected to take place, e.g. through the development of guidelines, and work on this will continue in 2021.

In addition to the planned revision of the IMO initial strategy in 2023, this EEXI/CII package is scheduled to be revised as well, by 1st January 2026, to ensure that the 40% target can be met with the measures proposed.

Another draft short-term measure which has matured in 2020 is the industry short-term measure proposal to establish, in the IMO, an International Maritime Research and Development Board (IMRB) and Fund (IMRF), together with a mechanism for providing the necessary core funding from shipping companies via a mandatory system of R&D contributions per tonne of marine fuel oil purchased for consumption by ships. MEPC 75 agreed that the IMRB - IMRF proposal should be given further consideration at MEPC 76 in June 2021. However, the political dynamic of the IMO debate is becoming ever more complicated, due to the separate debate about MBMs as well as the EU proposal to extend the EU Emissions Trading System to shipping. As the technologies necessary to achieve the ambitious 2050 IMO goals do not currently exist at a scale or in a form commercially viable for widespread use by international shipping, especially for transoceanic voyages, RBSA believes that support for massive research and development activity needs to be at the centre of the implementation of the IMO strategy. A price on carbon can only effectively reduce emissions, if the technologies to enable the transmission to a zero-emission industry are available to the entire shipping community.


Further improving the energy efficiency of the fleet…

While more R&D is needed to deploy technologies that can take the shipping industry effectively towards zero emission, other solutions and innovative technologies to improve the energy efficiency of the fleet are meeting more and more acceptance.
Operational measures

The simplest strategy for reducing CO2 emissions is to control the speed of a vessel, or to limit the engine power, thus limiting fuel consumption. A report by Transport & Environment and Seas at Risk found that a 20% reduction in speed resulted in a 24% reduction in CO2 emissions. Currently, there is no specific speed target for vessels set by the IMO, only the inclusion of speed within SEEMP and EEDI as an efficiency measure to reduce emissions. A speed limit as such however does not reward frontrunners with the best performing ships in term of energy efficiency, nor does it facilitate the research and innovation needed to decarbonise the world fleet. Additionally, sailing at excessively low power rates will not always be technically possible, as it could damage the engines or increase CO emissions, through a less efficient combustion caused by a low-load of engines.

Weather routing can be a cost-effective method of saving on fuel consumption and thus of GHG reduction. Installing technology to enable up-to-date weather predictions and transport schedules allows for better judgement of routes and schedule efficiency. The increased accuracy of arrivals and departures, and the avoidance of bad weather are said to allow for a fuel consumption reduction of 1 to 4%.

Technical measures

A study by ICCT1 found that wind assistance, e.g. by means of rotor sails, produces fuel savings of 1-12% per rotor sails, dependent on the route, weather conditions and ship type. The largest savings were found in windier locations and on vessels with numerous rotor sails. Rotors can be designed to move or retract and can be retrofitted on existing ships as well. Rotors can improve compliance to a stringent EEDI/EEXI. However, the effectiveness of wind technologies is highly dependent on weather and routes which means they aren’t suitable for certain ships or types of traffic. Vessels sailing at a steady speed, such as bulkers and tankers, are most suitable for this type of technology.

When wind assistance is coupled with other efficiency measures such as hull air lubrication, the level of fuel savings can increase and reduce emissions further. Pumping air bubbles underneath the ship, covering the hull, reduces frictional resistance and the accumulation of biological matter, resulting in reduced fuel consumption and emissions. Few vessels are however retrofitted with air lubrication systems, with the majority being integrated into new builds. As the development of more expensive alternative fuels increases, the use of air lubrication could increase, allowing more vessels to benefit from the efficiency savings available. The most suitable vessels for this technology are flat-bottomed vessels. Looking at vessels on order in the Clarksons’ database, there is a big appetite for this technology in the LNG fleet.

On the same level, hull coating and cleaning aim to address the same issue, namely improving efficiency through lowering friction. In the case of hull coating, instead of just cleaning the hull, a lower resistance, anti-fouling coating is applied aimed specifically aiming at reducing the drag caused by fouling on the hull. Costs can vary greatly, depending on vessel size and the quality of the product chosen.

Waste heat recovery systems recover the thermal energy from the exhaust gas and convert it into electrical energy, while the residual heat can further be used for ship services (such as hot water and steam). The system can consist of an exhaust gas boiler (or combined with oil fired boiler), a power turbine and/or a steam turbine with alternator. Redesigning the ship layout can efficiently accommodate the boilers on the ship to better fit these systems. Waste heat recovery is well proven onboard ships, but the potential can be variable depending on the size, numbers, usage and efficiency of the engines on board. Furthermore, these measures are usually not relevant for retrofitting, due to large costs and efforts related to redesign, steel work, extra weight, etc. The reduction potential is estimated at 3% to 8% of main engine fuel consumption.

1 Rotors and bubbles: Route-based assessment of innovative technologies to reduce ship fuel consumption and emissions’, ICCT, 2019

to deploy zero emission vessels within this century …


While engine power limitation and improved energy efficiency of vessels, e.g. by means of wind assistance, will already significantly reduce the industry’s GHG emissions, the goal of zero-emission waterborne transport can only be met when zero-emission alternative fuels can be purchased by shipowners and operators in all ports worldwide.

True sustainable maritime fuels will need to be produced from renewable energy sources. As the entire EU industry will need to decarbonize, it is still questionable whether, when and how much renewable energy will be available for the production of maritime fuels. This means that in de mid term, we need to acknowledge the importance and benefits of LPG, LNG and sustainable biofuels, supported by measures to reduce the Energy demand of our fleet.

Fuels of the future

“Renewable and low carbon fuels are projected at 5.5 to 13.5% of the fuel mix of shipping by 2030, while they would represent 86-88% of the energy use by 2050. Liquid biofuels would represent 39-40% of the fuel mix by 2050, while e-liquids would contribute up to 20%. Low carbon gases (bio-LNG and e-gas) are projected to represent 20 to 22% of the fuel mix and hydrogen another 7-8%.” 2
2 Sustainable and Smart Mobility Strategy: ETS, FuelEU, SRR & forecast for 2030 energy mix, p. 254


“A substitute low-carbon fuel for higher content fossil fuels (coal and oil) to reduce CO2 emissions in the near future.”

- ScienceDirect, Elsevier -

LNG in dual fuel technology

Incorporating dual-fuel technology is an important step towards the transition to climate neutrality in the long term. Making ships technically ready for the use of both LNG and another (conventional) fuel allows shipowners to gain more knowledge and experience. This can set the pathway for the easier implementation and use of other alternative, low-flashpoint future fuels, such as methanol and hydrogen. As such, LNG is to be seen as a means to prepare for the future and at the same time as the best solution to achieve both an immediate and significant cut in emissions affecting local air quality. Running on LNG almost entirely eliminates SOx and PM emissions, reduces CO₂ emissions in gas mode by up to 25% and strongly reduces the amount of NOx emissions. Burning LNG inevitably comes with an emission of methane slip, though shipowners have succeeded in reducing this in two different ways:

  • Optimization of combustion, to ensure methane is better burned in the combustion chamber and does not escape with exhaust gases.
  • Use of oxidation catalysts for reducing methane from exhaust emissions.3
LPG in dual fuel technology
Environmental benefits reside in the fact that LPG as a fuel does not contain any sulphur and substantially reduces CO2 (approximately 17% over the life cycle of the fuel) and NOx emissions, whereas particulate matters are almost halved as compared to a fuel-only engine. This engine technology is currently commercially available for 2-stroke engines and applied to LPG carriers. The fuel is easier to handle than LNG, as cryogenic materials are not required for the fuel tanks. Such systems therefore require lower investment costs. Using LPG as fuel will pave the way for a future deployment and use of ammonia when this technology becomes available, due to the compatibility of materials and expected similarities in engine design.4

Biofuels are derived from organic substances like food or agricultural waste. A biofuel can be a net-zero carbon emission fuel, meaning that the amount of CO₂ contained in the biomass is naturally renewed in each generation of plants, rather than being released from fossil stores and increasing atmospheric CO₂. Biodiesel and BioLNG are biofuels that can be used as a ‘drop-in’ fuels5:

  • Biodiesel can as such be used on every vessel, replacing conventional marine diesel oil.
  • BioLNG can be used on board of vessels currently running on LNG without any technical modification for storage, handling and combustion in contrast to fossil LNG.

3 DNV GL: Alternative Fuels Online Conference (Oct 2020)
4 DNV GL: Alternative Fuels Online Conference (Oct 2020)
5 Drop-in fuels are alternatives to existing liquid fuels without any significant modification in engines and infrastructures. According to IEA, “Drop-in biofuels are liquid bio-hydrocarbons that are functionally equivalent to petroleum fuels and are fully compatible with existing petroleum infrastructure”.



“A fuel that is derived partly or wholly from a source other than petroleum and that is less damaging to the environment than traditional fuels.”

- Merriam Webster -

Hydrogen (H2)

Last September, BeHydro - a joint venture between CMB and ABC Engines - launched the first hydrogen-powered dual-fuel (hydrogen-diesel) engine with a capacity of 1 MW. The new engine offers the opportunity to reduce CO2 emissions by up to 85%. BeHydro is now planning to develop larger dual-fuel engines of up to 10 MW and to develop a mono-fuel hydrogen engine which will take carbon emissions reductions on a further step forward, reducing C02 emissions by 100%.

Using hydrogen as a fuel still faces challenges such as the amount of energy needed to produce green hydrogen, along with its high flammability, storage and transportation. Currently, these systems are expensive and take up significant space, reducing cargo potential. Nevertheless, a report by the ICCT found that 43% of container vessel voyages in 2015 along the US-China shipping corridor could be completed using hydrogen with no changes to cargo volume or refuelling.

Ammonia (NH3)
Made using a mixture of hydrogen and nitrogen gas, ammonia is a potential zero-emission fuel. As it is easier to liquefy than hydrogen, has a higher energy density and is easier to transport, it could have greater commercial viability than hydrogen, especially for those vessels engaged in deep-sea traffic. YARA International explained in one of our MIDC sessions that the energy loss during the NH3 synthesis is relatively low (13%), which is due to the exothermic reaction of the Haber-Bosch process, where the steam generated is reused to increase the pressure from 30 to almost 60 bar. This makes ammonia more energy-efficient in the value chain than liquid hydrogen.
Consumption: ammonia is more energy efficient in the value chain than hydrogen
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Ammonia use has a 15% loss, whilst liquid hydrogen has a loss of 46%, from H2 production to direct use at customer. When cracking ammonia back to hydrogen at the end-customer the ammonia loss would be 25% in total.

Just like hydrogen, ammonia also still needs to overcome some challenges:

  • Currently the IGC code does not allow toxic cargoes to be used as a fuel.
  • Ammonia slip: Although ammonia is not a GHG, there is a safety/toxicity issue that needs to be addressed.
  • Operational venting.
  • Gas-freeing operations for maintenance purposes. If this is done shoreside, you will have to deal with ammonia vapours which are probably not allowed at the terminal. In addition, after the tank has been gas-freed, “hot air” (nitrogen) needs to be circulated for some time because ammonia goes into the pores of the steel and keeps reaching out. This will bring a lot of smell as well.
As new and existing ships will still need liquid fuels for a long period of time, renewable methanol can offer a viable solution, bearing in mind that sea-going vessels easily cover a lifespan of more than 20 years. Although the energy density of methanol is only around half that of marine gasoil or heavy fuel oil, it is relatively competitive in comparison to other alternative sustainable fuels today. Renewable methanol can be burned in engines with minor modifications and easily be stored onboard. In addition, it has an existing distribution infrastructure in place. In order to comply with the Tier III NOx limits, water needs to be added to the methanol as a lower-cost alternative compared to existing technologies like SCR and EGR.

One of the main remaining hurdles will be the provision of sufficient and safe alternative fuels and energy from renewable sources by fuel suppliers and ports. Discussions on if and how the shipping industry can be held responsible for the well-to-tank or well-to-wake emissions of alternative powers systems really kicked off at the IMO and at EU level and are expected to dominate the discussion in 2021.

Analytical work undertaken and published in 2020 by the University Maritime Advisory Services (UMAS) and the Energy Transitions Commission (ETS) calculated that at least USD 1 trillion in investments is needed to decarbonize shipping. The analysis furthermore showed that the largest share of investments is needed in the land-based infrastructure and production facilities for low-carbon fuels—around 87% of the total. This includes investments in the production of low-carbon fuels, and the land-based storage and bunkering infrastructure needed for their supply.


Channelling private capital to support the transition to and construction of a climate-neutral economy…

In order to meet the EU’s climate and energy targets for 2030 and reach the objectives of the European Green Deal, it is fundamental to direct investments towards sustainable projects and activities. To achieve this, a common language and a clear definition of what is ‘sustainable’ is needed. This is why the action plan on financing sustainable growth called for the creation of a common classification system for sustainable economic activities.

The EU taxonomy is a classification system, establishing a list of environmentally sustainable economic activities. It is an important enabler to scale up sustainable investment and to implement the European Green Deal. Notably, by providing appropriate definitions to companies, investors and policymakers on the economic activities deemed to be environmentally sustainable, this taxonomy is expected to create security for investors, protect private investors from greenwashing, help companies to plan the transition, mitigate market fragmentation and eventually help shift investments to where they are most needed.

The Taxonomy Regulation was published in the Official Journal of the European Union on 22 June 2020 and entered into force on 12 July 2020. The Taxonomy Regulation tasks the Commission with establishing the actual list of environmentally sustainable activities by defining technical screening criteria for each environmental objective through delegated acts.

The European Commission launched a public consultation on November 20 on the first two sets of criteria (climate change mitigation & adaptation) for determining which economic activities can qualify as environmentally sustainable, giving stakeholders one month to react to this first draft. The criteria for the maritime industry can be found under chapter 6.10: Sea and coastal freight, chapter 6.11: Sea and coastal passenger and chapter 6.11: Sea and coastal passenger and freight – retrofitting.

For ease of reading, these draft criteria were translated into the matrix below:

Substantial contribution: vessel not dedicated to the transport of fossil fuels + at least one of the criteria
Freight Passenger Retrofit
Criterion a Zero direct emissions Min 10% fuel consumption reductions in gr/dwt/Nm, as demonstrated by CFD, tank tests or similar calculations
Criterion b 2022-2025 Hybrid vessels with min 50% of zero direct emission fuel mass or plug-in power of their normal operation
Criterion c 2022-2025 (short sea) For coastal services: 50% lower than the average reference CO2 emissions value defined for heavy duty vehicles N/A
Criterion d 2022-2025 Attained EEDI value 10% below the EEDI requirements applicable on 01/01/2022

In order to preserve our marine ecosystem, above and under water.

Measuring emissions and water quality is easier than measuring biodiversity changes, which poses challenges to policymakers. It’s estimated that two thirds of marine ecosystems have been ‘severely altered’ by human actions. So, apart from the main issues currently under consideration by legislators, RBSA keeps supporting more research on other marine pollutants as well, to allow for evidence-based development of sustainable international regulations.
Underwater radiated noise
The EU Member States and the EU Commission submitted a proposal to IMO in 2019 supporting the earlier call by Canada and other countries to introduce a new output work item on noise emission reduction. To anticipate on the future roll-out of this topic, RBSA engaged in a project together with the Belgian Federal Public Service of Health, Food Chain Safety and Environment and the Belgian Federal Public Service of Mobility and Transport. The study monitored, amongst others, the noise emissions linked with CO2 reduction measures taken on board of Belgian ships. The outcome will be submitted to IMO for information and dissemination purposes in 2021.
Exhaust gas cleaning systems

For several years, IMO has authorised the use of exhaust gas cleaning systems as a means for shipowners to comply with sulphur emission limits. In the early days, the installation of these systems was even encouraged by the European Union. Some frontrunner shipping companies installed these systems in good faith at that time (to avoid emitting more and more sulphur into the air). RBSA has never been very supportive of the concept, but our association has always acknowledged that companies that have installed these systems in good faith should not be punished.

However, through increasing awareness and research and given the availability of safe and compliant new low-sulphur fuels, RBSA believes that the time has come to reconsider the concept of open-loop scrubber systems and to examine a possible restriction on the installation and/or use of any new EGCS. Therefore, RBSA supports the ambition of the EU and its Member States to evaluate and harmonise the IMO rules and guidance on the discharge of liquid effluents from EGCS into waters, including conditions and areas. This output remains on the 2020-2021 biennial agenda of the PPR Subcommittee and the provisional agenda for PPR, although delay due to the pandemic can be expected here as well.

Underwater radiated noise

Since 1 January 2020, new international measures regarding the sulphur content of bunker fuels have entered into force. RBSA has always been advocating these strict regulations and low sulphur fuels and therefore we have welcomed its final entry into force. Reducing the sulphur content of fuels to 0.5% outside SECA’s (and 0.1% inside the SECA’s) will deliver significant environmental benefits, not least to the health of coastal populations.

RBSA as well as our colleagues in the Netherlands and Germany and the ports located in the ARA region (Antwerp -Rotterdam – Amsterdam and Hamburg) have been advocating the introduction of a bunkering licensing scheme. The scheme would allow competent authorities to monitor bunker deliveries and to better ensure their quality and compatibility, by increasing the transparency throughout the whole bunker delivery chain.

An IMO correspondence group has been set up now to review and amend, as appropriate, the indicative example of a license for fuel oil supply. However, due to time constraints, a number of the documents submitted to the 75th session of the IMO’s MEPC were deferred until MEPC 76. If and how MEPC 76 will be able to further discuss the issue remains to be seen, as MEPC 76 has also been scheduled as a virtual meeting, with severe time constraints. In the meantime, the indicative example of a license, which is intended as a base document which states might adopt voluntarily, is still being discussed in the IMO correspondence group.