Hydrogen in Shipping: Potential, Practice and Perspective Toward 2050
Author: Jeroen Berger • Publication date:
In the transition to zero-emission shipping, hydrogen is developing into a key component of the maritime energy landscape. Previously regarded as a long-term technology, it is now increasingly being used in pilot projects, newbuilds and regulatory frameworks. Its appeal lies in its emission-free operation: when properly integrated into a new or existing vessel, the use of hydrogen in fuel cells or modified combustion engines results primarily in water vapor, with no emissions of carbon dioxide (CO2), particulate matter (PM) or nitrogen oxides (NOx).
However, large-scale deployment remains complex. Hydrogen is not an energy source, but an energy carrier. Its climate impact is therefore determined by the complete well-to-wake chain, including production, distribution, storage and onboard conversion. This entire chain is what determines whether hydrogen can contribute to emission reduction in the maritime sector.
This article examines hydrogen’s role in shipping across the domains of technology, regulation and strategy. It covers use cases in inland, coastal and deep-sea shipping, in relation to standards, certification requirements and policy frameworks. It also compares hydrogen with other alternative fuels and energy carriers. The analysis provides strategic guidance for shipping companies, shipowners and technical decision-makers looking to position themselves within an emissions-driven market. In light of the 2030 emission targets and the longer-term sustainability goals toward 2050, hydrogen is not an optional solution but a key technology that requires informed and deliberate choices.
Hydrogen in Maritime Context: Forms, Variants and Applications
In the maritime sector, hydrogen offers both zero-emission potential and technical complexity. As the smallest and lightest element in the periodic table, it has a high energy content per kilogram, approximately three times that of diesel. However, its low volumetric energy density in gaseous form presents significant storage and transport challenges. For onboard use, hydrogen must be conditioned through compression, liquefaction or chemical bonding to a carrier material.
Depending on the vessel type, sailing profile and required energy density, different storage options can be considered. Compressed hydrogen (CH2), stored at 350 to 700 bar, requires high-pressure composite tanks and is primarily suitable for short distances or lower power needs. Liquefied hydrogen (LH2), produced by cooling to –253 °C, has a higher energy density per liter. However, the liquefaction process is energy-intensive and imposes strict requirements for insulation, safety systems and system integration.
An alternative is the use of Liquid Organic Hydrogen Carriers (LOHCs), where hydrogen is chemically bonded to a liquid carrier such as dibenzyltoluene. These remain liquid at ambient temperatures, making conventional storage systems sufficient. However, hydrogen must be released onboard through dehydrogenation, which adds considerable system complexity. LOHCs are mainly suitable for use cases where high-pressure or cryogenic conditions are not feasible.
The choice of storage method is directly linked to hydrogen production routes. Grey hydrogen, produced from natural gas via steam reforming, results in significant CO2 emissions and does not meet climate targets. Blue hydrogen is technically identical, but includes carbon capture and storage (CCS). Climate benefit is only achieved if capture efficiency is demonstrably high, which is not always the case.
Only green hydrogen, produced via electrolysis using renewable electricity, complies with the sustainability criteria under the FuelEU Maritime Regulation and the updated IMO GHG reduction strategy. Both frameworks apply the well-to-wake principle, meaning that emissions from production, distribution and onboard use are assessed as a whole. As a result, grey hydrogen does not offer climate benefits in regulated markets, even if its use onboard is emission-free.
In addition to storage and production, the conversion method determines how hydrogen can be used onboard. One option is modified internal combustion engines, running on hydrogen either exclusively or in dual-fuel configurations with diesel. This approach builds on existing engine platforms, but produces NOx unless combined with after-treatment systems such as SCR catalysts.
Another option is fuel cells, which convert hydrogen electrochemically into electricity to power electric motors. This is a more efficient and quieter system that produces only water vapor, but it requires additional infrastructure for cooling, condensate removal and heat management. In inland navigation, vessels with Proton Exchange Membrane (PEM) fuel cells are already in commercial service. At the same time, companies such as CMB.TECH are developing dual-fuel engines in cooperation with manufacturers including MAN and Volvo Penta.
Using hydrogen is not a standardised decision. Only when storage method, production route and conversion technology are aligned with vessel design, operational profile and regulatory framework can hydrogen deliver on its potential as a zero-emission maritime energy carrier.
Technology Status and Application by Maritime Segment
Hydrogen technology has different applications across maritime segments. Inland, coastal and deep-sea shipping each have specific requirements in terms of storage, energy density, power demand and operational flexibility. As a result, various application pathways are emerging, each with its own technical, regulatory and logistical implications.
In inland navigation, the focus is on demonstration projects combining PEM fuel cells and electric propulsion. This configuration is suitable for small to medium-sized vessels with sufficient space for high-pressure storage, such as bundled tanks or swap containers. The Rhine corridor serves as a pilot area.
A leading example is the MS Antonie, a dry cargo vessel with a capacity of approximately 3,700 tons, operating emission-free on green hydrogen since late 2023. It is the first newbuild inland vessel in the Netherlands to run entirely on a fuel cell system. The Antonie transports cargo between Delfzijl and Rotterdam for Nobian, exchanging empty hydrogen containers for full ones in port.
Bunkering infrastructure for this setup is still under development. Bunkering or container exchange is currently only possible in a few locations, including Rotterdam and Duisburg. This highlights the demonstration status of current applications. Scaling up will require standardized and robust logistics along main waterways.
In coastal shipping, the higher power demand requires greater energy density and system reliability. Liquid hydrogen is being tested as a primary fuel in this segment. A case in point is the Norwegian car and passenger ferry MF Hydra, operational since 2023. This 82-meter vessel is equipped with two PEM fuel cells of 200 kW each and demonstrates that cryogenic storage is technically feasible and safe to integrate into maritime systems.
At the same time, dual-fuel technology is being developed as a transitional solution by modifying conventional engines to run partially on hydrogen. This approach combines emission reduction with operational flexibility. CMB.TECH is actively working on this setup with engine manufacturers including Volvo Penta and MAN. Field tests have shown CO2 reductions of up to 80 percent while retaining diesel as a backup.
In ocean shipping, with high energy demand and long voyages, direct use of hydrogen remains rare. Its low volumetric energy density makes onboard storage technically and economically challenging. The focus is therefore shifting to derived fuels such as green ammonia and synthetic methanol, in which hydrogen is chemically bonded. Methanol is liquid at ambient temperature, ammonia at –33 °C. Both are easier to bunker and can be integrated into existing tank infrastructure. Their adoption in ocean shipping is accelerating due to compatibility with retrofit and existing supply chains.
However, some direct hydrogen projects are underway. In the EU FLAGSHIPS project, for instance, a French push tug and a Norwegian ferry are being fitted with a total of 1.2 MW in PEM fuel cells. These vessels operate on fixed, predictable routes, which simplifies the use of hydrogen technology. Still, large-scale application in intercontinental shipping remains limited to pilots. Only with improvements in storage compactness and fuel cell cost-efficiency can hydrogen compete with conventional or synthetic alternatives.
In all segments, success depends on proper system design, strict safety measures and long-term validation. Most projects currently operate under temporary exemptions or pilot regulations, as existing classification rules, such as the IGF Code (for ocean shipping) and ES-TRIN/CESNI (for inland shipping), do not yet fully cover hydrogen-specific systems.
Classification societies such as Lloyd’s Register and Bureau Veritas are closely involved in technical validation. In the Netherlands, the Human Environment and Transport Inspectorate (ILT) plays a central role in trial operations, based on the Inland Waterways Regulation under Directive (EU) 2016/1629. This allows deviation from standard requirements if safety can be demonstrated. It provides a practical basis for future rulemaking once the technology has been sufficiently validated.
Policy Frameworks, Funding and Strategic Support
Hydrogen adoption in shipping is not driven by technology alone. Policy frameworks and financial mechanisms are just as decisive in shaping market development and investment decisions. European and national regulations impose emission reduction targets, while dedicated subsidies and public co-financing accelerate the shift from innovation to operational application.
At the European level, the Green Deal provides the strategic foundation for climate policy. Within this framework, the Fit for 55 package is key, including the FuelEU Maritime Regulation, which specifically targets ocean shipping. Starting in 2025, this regulation requires shipping companies operating seagoing vessels of ≥5,000 GT in EU, Norwegian or Icelandic ports to gradually increase the share of renewable and low-carbon fuels onboard. The maximum allowed greenhouse gas emissions per energy unit must decline in steps, with mandatory reduction targets set for 2030, 2035 and beyond.
This requirement covers the full fuel chain. Under the well-to-wake principle, emissions from fuel production and distribution are included in the calculation, not just emissions from onboard use. Companies that fail to comply risk penalties or operational restrictions, such as limited port access. In parallel, the International Maritime Organization (IMO) is working on global alignment through its updated GHG Strategy, adopted in July 2023. This strategy sets a net-zero target around 2050, with interim reduction goals of 20 to 30 percent by 2030 and 70 to 80 percent by 2040 compared to 2008.
Additional requirements for shore power use will take effect from January 1, 2030. Passenger and container ships calling at ports covered by the Alternative Fuels Infrastructure Regulation (AFIR) must then use shore-side electricity. Broader coverage for all major EU ports is expected by 2035.
The policy direction is clear: hydrogen and its derivatives are not optional technologies, but essential components for compliance with upcoming regulations. At the same time, regulation alone rarely leads to large-scale adoption. Therefore, both national and EU-level funding programs are in place to support technological innovation and deployment.
In the Netherlands, the Netherlands Enterprise Agency (RVO) plays a central role. Subsidy schemes such as the Inland Vessel Sustainability Subsidy (SRVB) and the Sustainable Shipbuilding Subsidy (SDS) support investments in hydrogen technology onboard, including fuel cells, electric propulsion and safety systems. Hydrogen bunkering infrastructure is also eligible for funding. Scheme names and terms may vary each year, so current conditions must always be checked via RVO.
In addition, the DEI+ (Demonstration of Energy and Climate Innovation) and MOOI (Mission-driven Research, Development and Innovation) programs support pilot projects and system integration. These also apply to inland shipping, which falls outside the scope of the FuelEU Maritime Regulation but is governed by ES‑TRIN and CESNI.
At the European level, Horizon Europe supports cross-border research and demonstrations, including projects such as FLAGSHIPS, MARANDA and HySeas. The EU Innovation Fund provides funding for large-scale demonstrations of low-emission technologies, including applications of hydrogen and ammonia in shipping.
Infrastructure development is supported under the Connecting Europe Facility (CEF), with a focus on strategic bunkering locations along the TEN-T corridors. The RH₂INE Kickstart Study is a key example. The Netherlands and Germany, along with ports such as Rotterdam and Duisburg, are developing a cross-border hydrogen corridor. CEF funding criteria emphasize scalability, intermodal connectivity and cross-border impact.
This combination of regulatory pressure and financial support forms a comprehensive framework. On the one hand, emissions targets are legally binding. On the other hand, investment risks are reduced through targeted co-financing. For shipping companies and shipowners looking to take a strategic position in the energy transition, this creates a clear path forward.
However, projects must demonstrably contribute to policy objectives and be supported by a solid business case to qualify for funding, certification and access to regulated markets. Over the coming years, successful pilots and initial commercial deployments will drive broader market rollout. Companies that act early, by applying for subsidies, participating in demonstration programs or forming strategic partnerships, can strengthen their market position and actively contribute to the development of a zero-emission maritime system.
Hydrogen Infrastructure and Bunkering: Logistical Preconditions
Although onboard hydrogen systems are advancing rapidly, shore-side infrastructure remains a structural bottleneck. Without reliable, safe and scalable bunkering facilities, hydrogen use will remain limited to pilot projects. Infrastructure is not a secondary condition, but a core requirement for successful hydrogen-based zero-emission shipping.
In the Benelux, particularly in Belgium and the Netherlands, the first steps have been taken to build a functioning hydrogen bunkering network. In the Netherlands, bunkering locations are planned in Rotterdam, Amsterdam and inland ports such as Arnhem. Belgian ports, including Antwerp and Ghent, are developing hydrogen hubs. These projects are largely in the pilot phase and rely heavily on co-financing through programs such as the CEF and national funding schemes.
A key feature of the current phase is the use of temporary solutions. Some ports use mobile refueling stations onshore, while others deploy bunker pontoons that deliver hydrogen under pressure. This offers operational flexibility but is not scalable without standardization. Large-scale deployment requires harmonized technical and operational specifications that support regular use.
Along the Rhine corridor, the main inland navigation route between the Netherlands and Germany, innovative logistics models are being developed. The RH2INE consortium has introduced a system in which hydrogen is delivered in standard containers filled at terminals and exchanged onboard. This setup enables continuous supply without permanent bunkering installations. For example, a vessel could load full containers in Duisburg and exchange them in Rotterdam.
This container-based model introduces new requirements in terms of safety and quality control. Hydrogen quality must be guaranteed through uniform purity standards. Bunkering procedures must include standardized connections, leak detection systems, gas venting protocols and clear communication between crew and shore personnel. Without these standards, operational risks remain high.
The European Union supports this approach through the TEN-T network and the updated Alternative Fuels Infrastructure Regulation (AFIR). Under this regulation, hydrogen is explicitly designated as an alternative fuel for which bunkering facilities must be available along core transport corridors by 2030. In 2023, several projects in Rhine ports and along the North Sea coast received CEF funding. Selection criteria included scalability, corridor integration and cross-border interoperability.
Norwegian and Swedish projects provide useful references. These countries are investing in cryogenic bunkering infrastructure for ferries and coastal shipping. Vessels such as the MF Hydra show that liquid hydrogen can be safely integrated into regular maritime operations. These demonstration projects provide valuable insights into permitting, technical integration and crew training. Through initiatives such as the Clean Hydrogen Partnership and regional programs like Hydrogen Valleys, this knowledge is being shared and applied to support further standardization across Europe.
Hydrogen’s success in shipping depends not only on technical innovations onboard, but also on a robust and internationally coordinated logistics chain. Only when bunkering infrastructure evolves in step with ship technology can hydrogen become a viable maritime energy carrier. This requires coordinated investment in vessels, shore systems, distribution networks and regulation. A fully integrated approach is essential to move from pilot phase to commercial scale.
Hydrogen vs. Alternatives: Comparison with Batteries, Methanol and Ammonia
Hydrogen is one of several low-emission energy carriers under development for maritime use. For shipping companies and shipowners, it is important to assess hydrogen within a broader energy mix that also includes battery-electric systems for short-range vessels, bio- and synthetic methanol as liquid alternatives, LNG for transitional use in deep-sea shipping, and green ammonia for longer voyages. Each alternative has specific application areas, maturity levels and system requirements. The optimal choice depends on operational profile, vessel type, emission targets and the availability of infrastructure and regulatory frameworks.
Battery-electric propulsion is currently a proven zero-emission option for short, predictable routes, such as ferries, harbor tugs and sightseeing vessels. These systems typically achieve electrical efficiencies above 85% and offer added benefits such as noise reduction and low maintenance. However, limited energy density remains a major constraint: longer voyages or higher power demands require large battery capacities, which can reduce cargo space or operational flexibility. Charging infrastructure for larger vessels is also still limited. As a result, battery-electric systems are well suited for urban and regional operations, but not yet viable as the primary propulsion method for deep-sea shipping.
Methanol, especially when produced from green hydrogen and captured CO2, is a technically accessible and relatively scalable fuel option. Because it is liquid at ambient temperatures and does not require pressurised or cryogenic storage, it can be used in existing engines and tank systems with limited modifications. Its lower energy density compared to diesel means more frequent bunkering or larger storage volumes are required. While methanol combustion does emit CO2, the fuel can still be climate-neutral if the carbon is part of a closed synthetic cycle. Major shipping companies such as Maersk are investing in methanol for deep-sea transport, mainly due to its retrofit potential, fuel availability and alignment with future regulations.
Ammonia is gaining attention as a carbon-free fuel that produces no CO2 emissions during combustion or conversion. Its volumetric energy density is higher than that of liquid hydrogen, and its liquefaction at –33 °C under atmospheric pressure makes storage and bunkering relatively manageable. However, ammonia is toxic and corrosive, and poses significant leakage risks. Application therefore requires strict safety protocols and specific modifications to systems and crew training. Technical development is ongoing for pilot-ignition engines and fuel cells suitable for ammonia. Practical demonstrations, such as Japan’s first ammonia-powered tug, show that the technology is currently in the validation phase. Widespread adoption will only be feasible once safety controls and green production are secured.
Hydrogen plays a bridging role in this transition. It can be used directly in fuel cells or modified combustion engines, and it also serves as a feedstock for synthetic fuels like methanol and ammonia. When produced via electrolysis with renewable electricity, hydrogen enables a fully zero-emission well-to-wake cycle. However, direct use requires high system standards: high-pressure or cryogenic storage, integrated cooling systems, ventilation, leak detection and specialised bunkering procedures. While methanol can be integrated into existing infrastructure relatively easily, hydrogen demands a full system approach that addresses technology, regulation and logistics simultaneously.
Choosing an energy carrier is not a one-size-fits-all decision but a strategic consideration based on vessel type, operational requirements and investment timelines. In urban logistics and short-haul shipping, the emphasis is on electrification. In transoceanic container transport, methanol is currently the most feasible option. In bulk shipping, ammonia is being actively explored. Hydrogen supports both direct applications and the production of synthetic fuels. As such, it is a critical enabler in the maritime energy transition toward 2050.
Implications for Strategy, Investment and Certification
Adopting hydrogen technology in shipping requires more than a technical upgrade. For shipping companies and shipowners, it involves reassessing strategy, investment policy and day-to-day operations. Hydrogen system integration calls for a comprehensive approach that balances technical choices, financing, safety and collaboration with supply chain partners.
Financially, switching to hydrogen usually involves higher upfront costs than conventional propulsion. Fuel cells, cryogenic tanks, integrated cooling systems and safety infrastructure represent significant capital investments. Implementation also tends to take longer due to extensive certification procedures and regulatory coordination. However, early adopters can realise clear benefits. In addition to grants and tax incentives, green loans and leasing options are available through public funding. A forward-looking investment profile may also improve access to contracts with shippers that have strict environmental requirements. Regulatory pressure from authorities and sustainability demands from clients are reinforcing each other: operating emission-free brings both compliance and competitive advantage.
Certification and compliance are also key. Both the fuel and onboard systems must meet national and international standards. For ocean-going vessels, the International Code of Safety for Ships using Gases or other Low-flashpoint Fuels (IGF Code) applies. This IMO framework sets safety requirements for the design, construction and use of ships powered by low-flashpoint fuels, including LNG and, increasingly, hydrogen. A hydrogen-specific extension is currently under development.
In inland shipping, the relevant standard is ES-TRIN (European Standard laying down Technical Requirements for Inland Navigation vessels), which specifies minimum technical criteria for vessels operating in EU inland waters. ES-TRIN is supplemented by CESNI (European Committee for Drawing up Standards in Inland Navigation), which oversees harmonisation of technical regulations for inland shipping.
Each hydrogen project follows a rigorous certification process. Classification societies such as Lloyd’s Register, Bureau Veritas and DNV are closely involved in assessing designs and safety systems. In the Netherlands, the Human Environment and Transport Inspectorate (ILT) monitors compliance. For cross-border operations or non-standard applications, review boards from CCR or CESNI are often involved, especially when projects deviate from current standards. The result is a binding regulatory framework that ensures safety, compliance and international interoperability.
Engaging classification societies and inspectors early, ideally during the design phase, helps avoid delays during construction and commissioning. At this stage, structured risk assessments should be performed, such as Hazard Identification (HAZID) for identifying safety risks and Hazard and Operability Studies (HAZOP) for analysing process deviations. These steps help identify and mitigate risks early, accelerate permitting and increase the confidence of insurers and financiers.
Operational procedures must also be updated. Hydrogen presents different safety risks than diesel or LNG. It is highly flammable, has small molecules that diffuse easily, and disperses rapidly when leaked. The liquefied form adds cryogenic hazards such as frostbite and material fatigue. Crews must be specifically trained in gas detection, ventilation, leak recognition and safe handling of bunker hoses or container exchanges. This training goes beyond technical instructions and includes safety culture and awareness. It improves onboard competency and meets the expectations of regulators and insurers, who require clear risk management for project approval.
Strategic investment in hydrogen requires a step-by-step roadmap toward low-emission or climate-neutral operation. Which vessels are suitable for newbuild or retrofit with alternative fuels? Key decision points include engine replacement, mandatory reclassification or midlife upgrades. Early involvement of suppliers, classification societies and clients enables risks, costs and responsibilities to be clearly defined. How proactively a company engages in this process will determine whether it emerges as a frontrunner or lags behind in the hydrogen economy.
Final Conclusion and Recommendations Toward 2050
Hydrogen will remain a central element in the maritime energy transition through 2050, provided it is applied using robust technology and embedded in a clear regulatory framework. Its greatest value lies in applications where electrification is not feasible and synthetic fuels like methanol or ammonia are not yet scalable or widely available. Only when hydrogen is produced through electrolysis with renewable electricity does it comply with the well-to-wake principle under FuelEU Maritime and the updated IMO GHG reduction strategy.
Now is the time for shipping companies and shipowners to align technology and investment decisions with the increasing regulatory pressure expected between 2030 and 2040. Ships entering service before 2030, such as inland vessels using PEM fuel cells, are already anticipating future requirements and can take a leading role. Validation, certification and access to bunkering infrastructure are the key enablers for successful deployment.
In the coming years, new developments in system integration, including high-efficiency electrolysers, lightweight cryogenic tanks and modular fuel cell systems, will increase the feasibility of hydrogen. At the same time, regulation will become more specific: within five years, both ES-TRIN and the IGF Code are expected to include detailed requirements for hydrogen as a primary fuel. Ships that are already designed to meet these standards will benefit in terms of classification, financing and commercial opportunities.
The clear recommendation for the years ahead: develop a hydrogen strategy tailored to each vessel type and operational profile, explicitly taking into account future regulation, system requirements and infrastructure. Link this strategy to key lifecycle moments, such as engine replacement, class renewal or midlife upgrades. Only in this way will hydrogen become a manageable and scalable investment for zero-emission shipping.