The development of hydrogen bunkering infrastructure at ports represents a critical step in the adoption of hydrogen as a marine fuel. As the maritime industry seeks to decarbonize, hydrogen offers a promising pathway due to its zero-emission potential when produced from renewable sources. However, establishing the necessary infrastructure for storage, refueling, and safety presents significant challenges. Ports worldwide are beginning to pilot hydrogen bunkering projects, with the Port of Rotterdam emerging as a leader in this space. The scalability of these initiatives, cost barriers, and the need for international collaboration remain key considerations. Additionally, comparisons with liquefied natural gas (LNG) bunkering provide insights into the unique requirements of hydrogen.

Hydrogen bunkering infrastructure requires specialized storage solutions due to the fuel’s low energy density and cryogenic or high-pressure handling needs. Two primary storage methods are being explored: liquid hydrogen (LH2) and compressed gaseous hydrogen (CGH2). LH2 must be stored at extremely low temperatures (around -253°C), necessitating advanced cryogenic tanks with high insulation efficiency to minimize boil-off losses. CGH2, on the other hand, is stored at pressures up to 700 bar, requiring robust containment systems to ensure safety. The Port of Rotterdam has invested in LH2 storage as part of its H2Gate project, which aims to establish a large-scale hydrogen supply chain for maritime and industrial use. Similar projects in Japan and Norway are also testing LH2 and CGH2 storage configurations to determine the most viable approach for ports.

Refueling protocols for hydrogen bunkering are still under development, with standardization being a major hurdle. Unlike conventional marine fuels, hydrogen refueling involves strict safety measures to prevent leaks, manage pressure differentials, and ensure compatibility between ship and shore systems. The Society for Gas as a Marine Fuel (SGMF) has published guidelines for hydrogen bunkering, emphasizing the need for risk assessments, emergency shutdown systems, and trained personnel. The Port of Rotterdam has implemented these protocols in its pilot projects, which include bunkering trials with inland shipping vessels. These trials help refine procedures for connecting/disconnecting hoses, purging systems, and monitoring fuel transfer. However, widespread adoption will require alignment with international standards, such as those being developed by the International Maritime Organization (IMO) and ISO.

Safety standards for hydrogen bunkering are stringent due to the fuel’s flammability range (4-75% in air) and low ignition energy. Ports must address risks such as hydrogen embrittlement of materials, leakage in confined spaces, and potential cryogenic hazards with LH2. The Port of Rotterdam’s H2Gate project incorporates multiple safety layers, including gas detection systems, explosion-proof equipment, and exclusion zones during bunkering operations. Lessons from LNG bunkering, which has been operational for over a decade, inform these measures. However, hydrogen’s smaller molecule size and higher diffusivity pose additional challenges, requiring tighter seals and more frequent integrity checks. The European Union’s Clean Hydrogen Partnership is funding research to enhance bunkering safety, with a focus on material compatibility and leak mitigation technologies.

Scalability remains a critical issue for hydrogen bunkering infrastructure. While pilot projects demonstrate technical feasibility, scaling up to meet the demands of global shipping requires massive investment. The Port of Rotterdam estimates that its hydrogen bunkering capacity will need to grow tenfold by 2030 to serve anticipated demand. This expansion involves not only storage and refueling infrastructure but also portside power generation for electrolysis and hydrogen liquefaction. Cost barriers are significant, with current LH2 bunkering costs estimated at two to three times higher than LNG due to energy-intensive liquefaction and handling. Reducing these costs will depend on technological advancements, economies of scale, and policy support. The Hydrogen Council projects that hydrogen bunkering costs could decrease by 50% by 2030 if production and infrastructure scale-up proceeds as planned.

International collaboration is essential to harmonize standards and enable cross-border hydrogen bunkering. The IMO’s initial strategy on reducing greenhouse gas emissions from ships includes hydrogen as a potential fuel, but global regulations are still evolving. Regional initiatives, such as the European Union’s Hydrogen Strategy and Japan’s Green Growth Strategy, are driving port-level collaborations. For example, the Port of Rotterdam has partnered with ports in Singapore and Los Angeles to share best practices and align safety protocols. Bilateral agreements between countries are also emerging, such as the Germany-Norway partnership on hydrogen maritime corridors. These efforts aim to create a cohesive framework for hydrogen bunkering, ensuring interoperability and safety across jurisdictions.

Comparing hydrogen bunkering with LNG bunkering highlights both similarities and differences. LNG infrastructure, now mature in many ports, provides a template for hydrogen in terms of storage tanks, bunkering vessels, and safety training. However, hydrogen’s lower energy density means bunkering operations must be more frequent or involve larger storage volumes. LNG bunkering benefits from established international standards (e.g., ISO 20519), while hydrogen standards are still in development. Additionally, LNG bunkering has faced public resistance in some ports due to safety concerns, a challenge hydrogen may also encounter despite its cleaner emissions profile. The transition from LNG to hydrogen bunkering could leverage existing infrastructure, such as cryogenic storage facilities, with modifications to accommodate hydrogen’s properties.

The Port of Rotterdam’s hydrogen initiatives illustrate the potential and challenges of large-scale bunkering infrastructure. Its H2Gate project integrates hydrogen production, storage, and bunkering, with plans to supply hydrogen to inland and ocean-going vessels. The port has allocated significant funding for infrastructure upgrades, including a dedicated hydrogen bunkering terminal. Early adopters, such as the inland container vessel Maas, have successfully demonstrated hydrogen refueling, providing valuable operational data. Rotterdam’s approach emphasizes public-private partnerships, with involvement from companies like Shell and Mitsubishi. This collaborative model could serve as a blueprint for other ports seeking to develop hydrogen bunkering capabilities.

Cost barriers remain a significant obstacle to widespread hydrogen bunkering. Current estimates suggest that hydrogen-fueled vessels have higher capital and operational costs compared to conventional or LNG-fueled ships. The bunkering infrastructure itself requires substantial investment, with LH2 terminals costing upwards of $100 million depending on scale. Governments and industry consortia are addressing this through subsidies and pilot funding. For instance, the EU’s Horizon Europe program has allocated funds for hydrogen bunkering projects, while national governments offer tax incentives for zero-emission shipping. Over time, as technology matures and production scales, these costs are expected to decline, but the transition period requires coordinated financial support.

The future of hydrogen bunkering hinges on continued innovation and cooperation. Ports must invest in infrastructure while ensuring compatibility with evolving international standards. Lessons from early adopters like Rotterdam will be invaluable for other regions. Scalability will depend on reducing costs through technological advancements and increased renewable hydrogen production. International collaboration is crucial to establish uniform safety protocols and enable seamless cross-border operations. While challenges persist, hydrogen bunkering represents a vital component of the maritime industry’s decarbonization strategy, with the potential to transform global shipping in the coming decades.