Introduction

Encouraging the use of clean energy vehicles is essential for reducing the carbon footprint of the transport sector, which accounted for 22% of worldwide energy-related carbon emissions in 2022 (ref. 1). Hydrogen fuel cell vehicles (HFCVs) are a category of clean-energy vehicles that convert hydrogen into electricity to power their electric motors, offering a zero-emission alternative to internal combustion engine vehicles and complementing battery electric vehicles (EVs). In 2022, the worldwide inventory of HFCVs increased by 40% from 2021, reaching more than 72,000 vehicles2. This fleet primarily consists of cars (80%), with smaller numbers of trucks (10%) and buses (~10%), although the market for trucks expanded at a faster pace in 2022 than that for buses and cars, with 60% growth relative to 2021 (ref. 3).

The environmental footprint of HFCVs is, however, contingent on the hydrogen production method. For hydrogen derived from fossil fuel-based processes, primarily steam methane reforming of natural gas, the resultant well-to-wheel emissions, encompassing the production, distribution and utilization phases, could rival or exceed those from vehicles with internal combustion engines4,5,6. Nevertheless, although the hydrogen production sector currently accounts for around a 2.5% share of global energy-related CO2 emissions, its decarbonization is being facilitated by the shift towards green production methods, namely electrolysis7. As of 2023, about 5–6% of hydrogen is now produced by the electrolysis of water, with this process increasingly being powered by renewable electricity as renewable capacity expands and more green hydrogen projects come online.

As well as having a crucial role in decarbonizing sectors in which direct electrification is challenging, such as long-haul transport, hydrogen also provides energy storage solutions for grid stability8, facilitating the integration of renewable energy into the electrical grid, particularly during periods of surplus production during which energy can be stored as hydrogen and later converted back into electricity9. The challenge of integrating green hydrogen into the energy and transport systems lies in the intermittency of renewable energy sources such as wind and solar power, which makes it difficult to achieve a consistent balance between hydrogen supply and demand, as well as the high production costs, which decrease the economic viability of scaling up green hydrogen production10. The hydrogen sector, thus, requires flexible solutions to adapt hydrogen generation or usage in response to real-time variations between supply and demand11. HFCVs have an important role in facilitating the integration of green hydrogen into the energy system by serving as flexible, distributed energy consumers. By aligning their refuelling demand with periods of surplus production, HFCVs help balance supply and demand and enhance overall system flexibility. The integration of hydrogen technologies with electrical engineering is also vital for developing advanced energy systems. This integration includes the design of electrolysers that efficiently convert electricity into chemical energy, the engineering of smart grids that can accommodate hydrogen as a dynamic load and storage medium, and the optimization of control systems that manage the production and distribution of hydrogen in sync with fluctuating energy demands12.

Crucial to the increasing adoption of HFCVs is the expansion of hydrogen refuelling infrastructure, which serves as the key link between hydrogen production and the transport and energy systems. In an ideal hydrogen-based zero-emissions transport system, there is a closed-loop cycle from renewable energy sources to the vehicles on the road (Fig. 1). The renewable energy is fed into the production of green hydrogen, which can be produced on-site at refuelling stations or centrally, with the hydrogen being delivered to refuelling stations through pipelines, tube trailers or other distribution channels before being processed and stored. The hydrogen is subsequently distributed to HFCVs through the refuelling infrastructure13.

Fig. 1: A hydrogen-based zero-emissions transport system.
figure 1

Concept of an integrated hydrogen transport system, underpinned by renewable energy sources. Renewable energy harnessed from wind and solar installations is used to produce hydrogen through electrolysis. This hydrogen production, which occurs during periods of energy surplus or low demand, capitalizes on the intermittent nature of renewable sources. To compensate for the variability of wind and solar generation, the system includes storage solutions to ensure a continuous hydrogen supply, with hydrogen delivered either through on-site production at refuelling stations or through pipeline networks from centralized production facilities. The hydrogen is then distributed through the refuelling infrastructure, which supports various types of vehicle: hydrogen trucks, buses and cars. These vehicles operate exclusively on hydrogen fuel cells, emitting only water vapour and, thereby, contributing to the decarbonization of the transport sector. The refuelling infrastructure is designed to accommodate fluctuations in energy availability and hydrogen demand, ensuring a resilient and sustainable transport system.

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In this Review, we discuss the technological developments facilitating the integration of HFCVs into the energy and transport systems. First, we review hydrogen fuel cell technologies, including performance, safety and operational aspects, for applications in HFCVs. Next, we examine the refuelling infrastructure required to increase the adoption of HFCVs and facilitate their integration into the transport system, before discussing the advances being made to overcome the challenges to scaling-up green hydrogen production and its integration into the energy system, including the key role of HFCVs. Finally, we delineate a roadmap for the integration of HFCVs into future sustainable energy and transport systems, considering emerging research avenues in infrastructure development, including strategies for the modelling and management of HFCV refuelling behaviour, the varied approaches for coupling HFCVs with the energy system, and policies and incentive schemes designed not only to accelerate the adoption of HFCVs but also to support their systemic integration, enable infrastructure expansion, and align hydrogen mobility with broader decarbonization goals.

Fuel cell technology and operation

The fuel cell influences the efficiency, emissions, driving range, refuelling duration and sustainability of HFCVs. State-of-the-art HFCVs equipped with advanced fuel cells and operating under optimal conditions can achieve system efficiencies (which refers to the efficiency of hydrogen conversion to electricity) of up to 60%, markedly higher than that of traditional combustion engines with efficiencies of around 30%14. Moreover, these state-of-the-art HFCVs can travel more than 500 km on a single refill, with refuelling times as short as 3 min, offering practicality comparable to that of gasoline (petrol) vehicles15. However, challenges such as fuel cell degradation, which can result in a reduction of electrical efficiency and power output by up to 20% over 5,000 h of operation, coupled with the need for effective operation management to optimize performance and extend lifespan, remain concerns for the long-term performance and reliability of HFCVs16. Addressing these issues is vital for the successful integration of HFCVs into the transport system.

Proton exchange membrane fuel cells

Proton exchange membrane fuel cells (PEMFCs) have become the cornerstone of HFCVs owing to their higher power output, compact design, lower operational temperatures and rapid start-up capabilities compared with other fuel cell technologies, which they surpass in terms of performance and environmental sustainability17. PEMFCs all use a proton exchange membrane (PEM) to transport protons from the anode to the cathode, but they vary in the exact membrane type, catalyst materials and operational parameters, giving rise to diverse performance profiles suited to different vehicular applications18 (Table 1).

Table 1 PEMFC technologies
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In a PEMFC, hydrogen gas flows to the anode, where a platinum-based catalyst facilitates the dissociation of hydrogen molecules into protons and electrons (Fig. 2). The protons migrate through the PEM, a selectively permeable polymer electrolyte that allows only protons to pass while blocking electrons. The electrons are forced to travel through an external circuit, generating electric current, before arriving at the cathode. At the cathode, another catalyst layer promotes the reaction between protons, electrons and oxygen, forming water as a byproduct and releasing heat19. There are multiple approaches to advancing PEMFC technology, and key performance metrics include the operational temperature, power density, specific power and durability, which determine the feasibility and competitiveness of PEMFCs in HFCVs. Operational temperature affects the thermal management complexity and system efficiency; power density and specific power determine the compactness and weight effectiveness of the fuel cell stack, which is essential for vehicle design; whereas durability refers to the ability of a fuel cell to maintain performance over its lifetime, often quantified as the total operating hours before performance degradation exceeds acceptable limits, such as a defined loss in power output or efficiency.

Fig. 2: Operation and design of proton exchange membrane fuel cells.
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a, During the operation of a proton exchange membrane fuel cell (PEMFC), the fuel (hydrogen) is introduced at the anode side and is oxidized at the anode catalyst layer, releasing electrons (e−) and protons (H+). The electrons travel through an external circuit creating an electric current, whereas the protons migrate through the electrolyte to the cathode side. Concurrently, air is supplied to the cathode side, providing oxygen that reacts with the incoming protons and electrons at the cathode catalyst layer to form water. This reaction at the cathode also releases heat. Excess fuel exits the system, ensuring that the fuel cell does not flood with reactants. The arrows indicate the direction of reactant flow and electron movement, with the electric current resulting from the flow of electrons being directed out of the cell to power an external load. b, Representation of the key components of a PEMFC, highlighting both current technology and future possibilities, including the bipolar plates with integrated flow channels or fields, gas diffusion layers, and catalyst layers on both the anode and cathode sides, with the proton exchange membrane (PEM) positioned centrally. Part b is adapted from ref. 18, Springer Nature Limited.

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Increasing the power density of PEMFCs is necessary to meet the power demands of a wide range of applications, from automotive to stationary power systems20,21. Typical power densities for PEMFCs used in HFCVs range from 1 to 2 W cm−2 at operating temperatures of around 60–80 °C (ref. 22). For practical vehicle applications, especially passenger cars and trucks, achieving a power density of at least 1.5 W cm−2 is often considered necessary to ensure that the fuel cell stack remains compact and lightweight while delivering sufficient power for driving performance and auxiliary loads. Increases in power density have been driven by component-level optimization (materials, design and performance enhancement) and system-level integration (how components, such as bipolar plates with structured flow channels, the gas diffusion layer and the catalyst layers, are assembled and interact). This combined approach has led to a decrease in internal resistance, better mass transport, efficient water management and higher reaction efficiency within PEMFs, all contributing to an increase in power density.

In parallel with efforts to enhance power density, advances have been made to increase the durability of PEMFCs, addressing challenges related to material degradation and long-term stability. One important focus has been the development of catalysts with tailored architectures23, such as nanocages and nanowires, which offer enhanced structural stability, resistance to particle agglomeration and improved tolerance to catalyst dissolution under prolonged operating conditions. In addition, mesoporous supports have been introduced to provide better anchoring for catalyst particles, minimizing catalyst migration and carbon corrosion, which are two major contributors to performance degradation. Membrane durability has also been increased through innovations such as reinforced composite membranes and thin-film composite membranes, which offer enhanced mechanical strength, greater chemical resistance and improved tolerance to mechanical stress caused by hydration and dehydration cycles. These membrane advances have enabled the stable operation of PEMFCs at higher temperatures and lower humidity than those with conventional Nafion-based membranes, expanding the range of conditions under which PEMFCs can reliably operate24. Collectively, these innovations have extended the operational lifespan of PEMFCs, with some systems now achieving over 10,000 h of continuous operation with minimal performance degradation, making them increasingly viable for demanding applications such as automotive and stationary power generation25.

Owing to concerns regarding the environmental impact of precious-metal extraction and supply issues, progress is being made towards more environmentally sustainable and economically feasible PEMFCs with non-precious-metal catalysts (NPMCs)26. PEMFCs with iron–nitrogen–carbon catalysts have achieved a durability and efficiency suitable for HFCV applications27. Further innovations in PEMFC development include the application of additive manufacturing techniques, such as three-dimensional printing of fuel cell components, which enables the creation of complex structures such as flow plates28 that help reduce pressure drops and increase the distribution of gases across the catalyst layer, increasing the system efficiency of HFCVs. Integration of Internet of Things (IoT) technology for smart monitoring within PEMFCs is another breakthrough, providing real-time data to support adaptive control strategies, predictive maintenance and efficient operational adjustments. Furthermore, hybrid systems that combine PEMFCs with other energy storage technologies, such as batteries or supercapacitors, could enable an increase in the peak power output and improved load management, making HFCVs more robust and versatile for a range of applications from everyday automotive use to supporting grid stability29.

State-of-the-art PEMFCs not only achieve high power densities and long durability but also demonstrate system efficiencies of 50–60%, balancing performance and fuel utilization. Modern systems are capable of cold starts at temperatures as low as −30 °C, meeting the demands of automotive applications. Additionally, advances in catalyst technology have reduced platinum loadings to below 0.1 mg cm−2, improving the cost-effectiveness and sustainability. The various types of PEMFCs have different advantages. Thin-film PEMFCs can exhibit power densities as high as 2.0 W cm−2, achieved through ultra-thin membranes that lower the internal resistance, with a durability range of up to 10,000 h, indicating their resilience and long-term viability30. High-density PEMFCs are designed to maximize power output per unit mass and volume, typically through the use of lightweight materials across the entire stack, and can exhibit specific powers of up to 3,000 W kg−1; this type of PEMFC is ideal for applications in which minimizing the mass is crucial. NPMC-based PEMFCs have sustainability advantages and have reached power densities of up to 0.8 W cm−2, but although the operational durability of 5,000 h reached with NPMCs is a promising step forward, further work is needed to increase their longevity to match that of precious-metal counterparts.

Fuel cell durability and safety

Fuel cell durability and safety are crucial in the operational management of HFCVs. Inadequate or excessive operation can lead to fuel cell deterioration, manifesting as diminished efficiency and increased failure rates, as well as potentially triggering safety concerns.

Degradation mechanisms and lifetime prediction

The decline in efficiency and power output during fuel cell operation necessitates precise fuel cell health prognostics, including state-of-health estimation and durability forecasts, to ensure optimal performance and longevity31. Comprehending the degradation pathways and the factors that influence the degradation is crucial to creating accurate models for predicting the health and lifespan of PEMFCs32,33. The main degradation phenomena within PEMFCs are the deterioration of membrane conductivity and the degradation of catalyst activity34. For example, catalyst layer corrosion and membrane thinning owing to chemical degradation decrease the efficiency of PEMFCs35. Moreover, platinum dissolution and oxidation of the carbon support at catalyst sites lead to a decrease in active surface area36. Operational factors such as cell hydration levels, operating temperature and load variations profoundly affect the durability and performance of PEMFCs37. Degradation mechanisms can be identified using diagnostic tools such as scanning electron microscopy for structural analysis and polarization curve testing for functional evaluation, or through computational approaches such as finite element analysis and electrochemical impedance spectroscopy modelling38.

Approaches for fuel cell health prognostics can be categorized into model-based, data-driven and hybrid techniques39. Model-based approaches strive to construct empirical, equivalent circuit or electrochemical models that replicate fuel cell functions and subsequently use parameter optimization techniques for ageing status prognostics40. Conversely, data-driven strategies predominantly focus on correlating observable characteristics with the state of health of the fuel cell, using statistical or machine learning methods to predict performance degradation41. Challenges include the complexity of the calculations required for electrochemical models, which limits their generalizability across different fuel cell types, whereas data-driven methods might not apply well across different fuel cell applications, limiting their real-world effectiveness. A solution lies in adopting hybrid strategies that merge the precision of model-based approaches with the adaptability of data-driven techniques, offering more accurate and dependable predictions for fuel cell health42. For example, a hybrid prognostic approach that combines digital twin technology (virtual representations of physical fuel cell systems created using real-time data and predictive modelling) with a deep transfer learning model based on stacked denoising autoencoders demonstrated high accuracy in real-time health monitoring and effectively predicted the state of health of PEMFCs, even under varying operating conditions, showing improved robustness compared with traditional data-driven methods43. A hybrid predictive model that merges an adaptive Kalman filter with a data-driven nonlinear autoregressive with exogenous input neural network can be used to forecast fuel cell degradation44; the model captures irreversible and reversible degradation processes and shows increased prediction accuracy compared with purely data-driven approaches. Moreover, a hybrid health-aware model predictive control strategy has been developed that integrates mechanism analysis with a data-driven neural network45. The predictive control strategy focuses on minimizing detrimental parameter variations within the internal stack and improves both fuel cell durability and real-time performance.

Safety protocols and fault detection

Safety is paramount to the widespread adoption of PEMFCs in the transport and energy sectors. PEMFCs can be vulnerable to operational stresses (such as membrane drying, over-pressurization and excessive heat), which increase the likelihood of safety issues, including catalyst degradation and membrane breaches46. To ensure the safe functioning of fuel cells, effective thermal regulation and real-time fault detection are essential47. Fuel cell thermal management systems are designed to maintain the fuel cell temperature within an optimal range that supports efficient operation and ensures safety48; this involves analysing how heat is produced and dispersed within the fuel cell, optimizing the fuel cell stack architecture, and implementing temperature control strategies49. Fault detection is based on sophisticated numerical modelling and real-time diagnostics. Numerical models for fault detection identify discrepancies between actual performance data and theoretical predictions50. However, applying these models to large-scale or complex fuel cell installations is challenging owing to uncertainties in model accuracy and variations in operational parameters51. By contrast, data-driven fuel cell fault diagnosis uses real-time data to identify irregularities across the fuel cell stack and to highlight deviations52. This approach necessitates categorized fault data for algorithm training, which can be challenging to compile accurately for the wide variety of fuel cell diagnostics. Integrating model-based and data-driven approaches increases the effectiveness of fault diagnosis in fuel cells53. For example, parameters and conditions indicative of fuel cell faults can be predicted through physical fuel cell models, which subsequently inform data-driven algorithms, thereby increasing the diagnostic precision and reliability54.

To further increase the safety and reliability of PEMFCs, advances are being made in multiscale diagnostic technologies and integrated monitoring frameworks55. Multiscale diagnostic technologies address safety concerns by combining macroscopic system-level analysis with microscopic inspections of component behaviour. Advanced imaging techniques, such as in situ neutron radiography and X-ray computed tomography, enable real-time visualization of water distribution and gas flow dynamics within a fuel cell stack, providing insight into potential safety risks and operational inefficiencies56. Emerging fault-tolerant control mechanisms are also being developed to enhance operational safety. These mechanisms leverage adaptive algorithms to dynamically adjust operating conditions, such as voltage, current density and reactant flow rates, in response to detected abnormalities. For example, when a fault is detected in a specific cell within a stack, the fuel cell stack management system can redistribute the load to prevent cascading failures. These adaptive strategies are further augmented by machine learning algorithms that analyse historical and real-time operational data to predict potential failures and optimize responses proactively57.

The development of standardized safety protocols for PEMFC applications is also gaining traction. These protocols encompass guidelines for system design, installation, operation and maintenance, tailored to various use cases, including automotive applications. International standards, such as ISO 14687 for hydrogen fuel quality and ISO 26142 for hydrogen detection apparatus, have a crucial role in ensuring consistent safety practices across the industry58. However, challenges remain in harmonizing these standards globally to accommodate regional variations in operational environments and regulatory requirements.

Given its flammability and low ignition energy, hydrogen leakage detection and mitigation are particularly important for PEMFC systems59. Hydrogen sensors with nanomaterial-based sensing elements are being explored for their high sensitivity and rapid response times60. These sensors are integrated into smart monitoring systems capable of triggering automatic shut-off valves and ventilation systems in case of a hydrogen leak, minimizing the risk of combustion. Furthermore, fault detection for hydrogen delivery infrastructure, such as pipelines and storage tanks, involves acoustic emission monitoring and distributed fibre optic sensing technologies, which can detect microcracks and stress-induced damage that might lead to leaks. Another key aspect of safety is the prevention of thermal runaway in PEMFCs. Research is progressing in the development of thermal runaway detection mechanisms, including infrared thermography and heat-sensitive coatings applied to key fuel cell components61. These methods enable the rapid identification of localized hot spots, which can indicate abnormal chemical reactions or component degradation. Additionally, thermal runaway suppression techniques, such as phase-change materials and liquid cooling systems, are being incorporated to absorb excess heat and maintain operational stability62.

The integration of digital twin technology offers a transformative approach to PEMFC safety and fault detection. By simulating the operational behaviour of fuel cells under various scenarios, digital twins can be used to identify potential safety risks and optimize fault detection strategies43. These virtual models also facilitate training for operators and engineers. Indeed, the human factor in safety management cannot be overlooked. Training programmes for operators, maintenance personnel and first responders are essential for ensuring the safe handling of PEMFC systems. These programmes should cover best practices for routine inspections, emergency shutdown procedures and hydrogen handling protocols. Enhanced safety culture within organizations, supported by regular safety audits and incident reviews, further strengthens the overall safety framework for PEMFC applications.

Fuel cell operation management

System efficiency is a pivotal parameter for HFCVs. Increasing the adaptability of fuel cells to fluctuating power requirements would align HFCVs more closely with the operational convenience of internal combustion engine vehicles. Nevertheless, subjecting fuel cells to conditions beyond their standard operational range might accelerate their degradation and diminish the economic viability of HFCVs63. Consequently, the development of efficiency-optimized operation protocols is imperative to enhance power delivery and responsiveness while safeguarding fuel cell durability. Considering that HFCVs operate under diverse conditions that affect fuel cell performance, such as ambient temperature, adaptive operation management is essential to ensure optimal functioning of HFCVs in varied environments. Balancing the efficiency, durability and environmental adaptability requires precise fuel cell management64,65.

Efficiency-optimized operation strategies

Operating fuel cells at elevated power outputs, such as to maximize output to meet sudden high energy demands, can initiate adverse reactions within the cell66. For example, pushing a PEMFC beyond its optimal system efficiency can lead to catalyst degradation or membrane drying67,68. Thus, the balance between system efficiency and fuel cell longevity must be managed by tailoring power output strategies and formulating efficiency-optimized operation protocols69. To realize such strategies, it is essential to develop electrochemical degradation models that precisely forecast the degradation mechanisms under varying operational states70. Additionally, insight into the internal state of fuel cells could guide the adjustment of these models to curb processes that accelerate wear. Comprehensive electrochemical degradation models grounded in historical operational data, including ambient conditions, load cycles and state of health, enable the fine-tuning of operational parameters to extend the service life of the fuel cell, considering its degradation behaviour and current condition71,72.

Adaptive fuel cell operations

The efficiency, power output, thermal management and durability of PEMFCs might vary under different scenarios. Adaptive operation management has a crucial role in addressing these operational uncertainties and ensuring the optimal performance of HFCVs tailored to specific environmental and usage conditions73. For example, the management of PEMFCs under extremely cold conditions, notably below −30 °C, presents challenges owing to factors such as decreased catalyst activity and membrane dryness, which affect fuel cell efficiency74,75. Adaptive operation management techniques, such as pre-conditioning the fuel cell to an optimal temperature range between 15 and 35 °C through thermal management systems that combine passive and active heating strategies, can be used76,77 to ensure that performance is maintained and to mitigate the risk of degradation. Similarly, adaptive cooling strategies are required in high-temperature environments to maintain system efficiency and prevent thermal degradation78. Passive cooling technologies, such as the integration of phase-change materials into fuel cell assemblies, are being explored to absorb and dissipate heat during operation. Meanwhile, active cooling systems that leverage thermoelectric coolers or liquid cooling loops are being fine-tuned to respond dynamically to heat generation patterns within the stack. These cooling methods are paired with predictive thermal models to ensure that temperature distribution across the fuel cell remains uniform, avoiding localized hot spots that could compromise component integrity.

To further optimize adaptive operation strategies, dynamic control algorithms have proved instrumental in managing the variability in PEMFC performance. These algorithms use real-time data from sensors that monitor parameters such as temperature, pressure, humidity and power demand79. By integrating predictive analytics and machine learning, adaptive systems can forecast operational anomalies and preemptively adjust parameters to maintain stability. For example, reinforcement learning-based controllers are being developed to optimize fuel cell stack operations under rapidly changing load conditions, such as acceleration and deceleration in HFCVs80, ensuring efficient energy delivery and prolonged system life.

A key focus area is the optimization of water management within PEMFCs under diverse operational scenarios. Adaptive water management techniques aim to achieve a balance between hydration and flooding of the membrane81. Humidification systems, such as electronically controlled humidifiers, enable precise control over water vapour levels in the gas flow, adapting to variations in external humidity and temperature. Additionally, microstructured flow fields with dynamic water-removal channels increase the drainage of excess water, preventing flooding while maintaining adequate membrane hydration. Adaptive fuel cell operations must also address durability concerns under high-load conditions82, which can accelerate the degradation of components. To mitigate these effects, load-sharing mechanisms have been introduced that distribute power demand across multiple stacks or incorporate auxiliary power sources such as batteries or supercapacitors. These hybrid energy management systems dynamically switch between power sources based on real-time demand, reducing the operational stress on PEMFCs and extending their lifespan.

Adaptive operation strategies for fuel flexibility are gaining traction to expand the application scope of PEMFCs80. Research into reformer-integrated systems has enabled the use of alternative fuels, such as methanol or ammonia, to generate hydrogen on demand. Adaptive control systems in these set-ups monitor the fuel type and adjust reforming parameters such as temperature and reaction time to optimize hydrogen production efficiency. This flexibility not only enhances the economic feasibility of PEMFC deployment but also reduces the reliance on infrastructure for high-purity hydrogen, particularly in remote or underdeveloped areas.

Infrastructure for HFCV refuelling

Essential considerations for developing hydrogen refuelling infrastructure to support HFCV adoption include fast refuelling times comparable to those of gasoline vehicles, sufficient geographic coverage to prevent range anxiety, compatibility with different HFCV tank pressures, a high-purity hydrogen supply to protect fuel cell durability, and the alignment of refuelling stations with green hydrogen production to support decarbonization.

Refuelling options and technologies

Hydrogen refuelling stations can be categorized into three major types — regular stationary, rapid stationary and mobile refuelling — each serving distinct applications with differing hydrogen pressures, refuelling speeds and power capacities (Table 2). Across all refuelling types, efficiency is consistently high (~90–95%), but power delivery capacity, deployment flexibility and refuelling duration vary, governed largely by the operational pressure and system design. These differences are crucial when tailoring infrastructure to regional needs, vehicle types and user behaviour. Refuelling stations should be strategically located to enable drivers to refuel without large detours and, thus, to increase the practicality of HFCVs for various activities83. Additional considerations such as potential wait times at stations and the speed of refuelling also influence user preference for the refuelling method84,85.

Table 2 HFCV charging infrastructure
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Stationary refuelling

Regular stationary refuelling stations are used in residential or commercial settings, often operating at pressures of ≤350 bars with refuelling durations of 30–180 min for residential (more suitable for overnight refuelling86) and 15–60 min for commercial applications. These stations are typically for light-duty, low-frequency usage. By contrast, rapid stationary refuelling is deployed at public and specialized commercial stations and offers high-pressure refuelling (commonly 700 bars), which substantially shortens refuelling times and makes rapid refuelling ideal for high-use fleet vehicles or long-range mobility, for which the turnaround time is crucial. Specialized stations are designed for high-throughput commercial fleets, such as buses and trucks, and are equipped with larger compressors, enhanced cooling systems and optimized high-flow nozzles to enable faster and more efficient hydrogen dispensing, with refuelling times of 3–10 min. By contrast, public stations serve a broader vehicle base and typically have more modest throughput capabilities, resulting in longer and more variable refuelling times (5–20 min). Although rapid refuelling minimizes downtime and maximizes the range and operational convenience87, disadvantages include higher equipment costs owing to the need for advanced high-pressure compressors, cooling systems and reinforced dispensing hardware, as well as greater energy consumption for compressing and cooling hydrogen to the required levels. Rapid refuelling can also exacerbate thermal stress on vehicle tanks and fuel cell components, potentially accelerating material fatigue over time if temperature management is not carefully controlled64. Additionally, maintaining consistent hydrogen purity during fast fills can be more challenging, increasing the risk of contaminants entering the fuel cell and affecting long-term performance. Currently, hydrogen refuelling infrastructure relies heavily on high-pressure tanks (up to 700 bars) for compressed gas storage. Cryogenic storage offers a higher density for liquid hydrogen, and solid-state materials are being explored for safer, lower-pressure storage alternatives88.

Mobile refuelling

Compared with stationary refuelling types, mobile refuelling units provide an intermediate refuelling option and enable flexible deployment to locations without permanent infrastructure. Mobile refuelling typically operates at hydrogen pressures of 350 bars and offers refuelling durations of 10–30 min, balancing convenience with operational limitations, such as smaller onboard storage and lower compression capacity. Despite their slower flow rates, compared with those of rapid stationary stations, mobile systems are particularly useful for private or temporary commercial operations, such as vehicle testing sites or remote areas, and can reduce vehicle downtime89. Additionally, mobile units can replenish their hydrogen supply during off-peak hours, optimizing energy use and potentially reducing operational costs90. Although mobile hydrogen refuelling has benefits over stationary methods, its widespread adoption has been limited. Challenges include developing efficient and safe hydrogen electrolysers and compressors91,92. Integrating these systems into a mobile platform that can reliably and safely dispense hydrogen requires advanced engineering to meet stringent safety standards, often varying by region93. When on-site hydrogen production is not available, ensuring a consistent hydrogen supply, especially in areas without existing infrastructure, necessitates innovative solutions for hydrogen production, storage and transport logistics94. Maintaining a ready stock of pressurized hydrogen to prevent customer delays increases the logistical and maintenance costs95. Furthermore, the lack of standardization in hydrogen refuelling interfaces between various HFCV models hinders widespread adoption96. These challenges underline the need for further innovation and investment to make mobile hydrogen refuelling a viable and widespread option.

On-site hydrogen production

On-site hydrogen production involves generating hydrogen on demand at the refuelling station. This approach reduces the reliance on external hydrogen supply chains, minimizes transportation costs and lowers the carbon footprint associated with hydrogen logistics97. There are two primary methods of on-demand hydrogen production: electrolysis and steam methane reforming. Electrolysis uses electricity to split water into hydrogen and oxygen, and it can be powered by renewable energy, offering a sustainable option98. Conversely, steam methane reforming generates hydrogen from natural gas, which is efficient and scalable but less eco-friendly owing to CO2 emissions99. The main challenge for on-site hydrogen production is the substantial initial investment required for the infrastructure, sometimes reaching millions of dollars100. The integration of renewable energy sources to power the electrolysis process can further increase the set-up costs. Despite these high initial costs, on-site hydrogen production remains a key strategy for ensuring a sustainable and self-sufficient fuel supply for HFCVs. The wind-to-hydrogen project being undertaken by the US National Renewable Energy Laboratory demonstrates the integration of wind turbines and photovoltaic arrays with electrolyser stacks for on-site hydrogen production101,102. This set-up allows for the storage of produced hydrogen for later use or its conversion back to electricity for the grid during peak hours103. This project demonstrates that the efficient production of hydrogen from renewable resources can make it cost-competitive with traditional energy sources104.

Pipeline hydrogen delivery

Hydrogen gas can also be conveyed through pipelines that directly link production sites to refuelling stations. This method improves the efficiency of the hydrogen distribution network, lowers the carbon footprint associated with hydrogen transportation, and supports the adoption of HFCVs by ensuring that the refuelling infrastructure can meet growing demand105. For example, the Port of Rotterdam in the Netherlands is working on integrating hydrogen production, storage and consumption within its premises, including a pipeline project in collaboration with Shell to connect a green hydrogen plant at Maasvlakte 2 to the refinery of Shell in Pernis106,107. On a national level, the Netherlands has started constructing a 1,200-km hydrogen pipeline network, with the first section expected to be operational in 2025. This network will link the industrial areas of Rotterdam and is part of a broader strategy to facilitate hydrogen transportation across the country and potentially to neighbouring countries by 2030 (ref. 108). Nonetheless, there are substantial challenges to the widespread expansion of hydrogen pipeline infrastructure109. For example, the construction of hydrogen pipelines necessitates considerable upfront investment, particularly for long-distance networks, presenting a financial barrier110. Moreover, the flammability of hydrogen, combined with its low ignition temperature, poses safety risks in pipeline delivery systems111. Owing to its small molecular size, hydrogen is prone to leakage112, and its high diffusivity increases the risk of forming explosive hydrogen–air mixtures. In addition, hydrogen embrittlement — a process whereby hydrogen weakens the structural integrity of metals — could lead to pipeline cracks or failures over time113. Thus, advanced monitoring and emergency response mechanisms are required to ensure the integrity and safety of the infrastructure, further increasing the complexity and cost of pipeline hydrogen delivery.

Mitigation of these safety risks requires a multifaceted approach. Advanced pipeline materials, such as high-strength composites with low hydrogen permeability, are increasingly used to reduce leakage risks and to increase resistance to embrittlement114. Real-time monitoring technologies, including fibre optic sensors and acoustic emission systems, aid in leak detection and in ensuring prompt intervention. Predictive maintenance, powered by artificial intelligence (AI), is also gaining traction to preemptively address material degradation and stress-induced failures. To further enhance safety, adherence to international standards, such as those from the American Society of Mechanical Engineers and the European Industrial Gases Association, is imperative. These standards guide the selection of pipeline materials, construction practices and operational protocols. Emergency response systems, such as automated shut-off mechanisms and rapid depressurization technologies, are also integral to minimizing the impact of potential incidents.

Planning refuelling infrastructure

Developing accessible and cost-effective hydrogen refuelling stations is crucial for enhancing consumer acceptance, minimizing the cost of refuelling and encouraging HFCV adoption. Planning of hydrogen infrastructure aims to extend refuelling accessibility, elevate service standards and optimize the societal benefits of hydrogen integration into the transport and energy sectors115. Challenges include economic and operational aspects116,117. Economic challenges encompass constraints such as capital investment, land availability, optimal refuelling strategies and user preferences. Operational considerations involve ensuring adequate refuelling capacity, maintaining high service quality and minimizing wait times at stations, crucial for user satisfaction and efficiency118.

The initial step in planning hydrogen refuelling infrastructure is to map the distribution of refuelling demand. For stationary refuelling, hydrogen demand projections rely on analyses of the mobility patterns of drivers, notably their routine travel endpoints. Early hydrogen infrastructure planning adapted methods from conventional fuel station network design, prioritizing station placement based on traffic flow and driver convenience, rather than hydrogen-specific factors such as production and storage119,120. This methodology accounts for HFCV range limitations and aims to optimize the flow of vehicles through refuelling stations, increasing service accessibility or reducing overall infrastructure costs. As HFCVs have different requirements compared with conventional vehicles, modelling HFCV refuelling demands introduces several complexities, including the need for high-pressure hydrogen storage, the variable refuelling time depending on station capacity and vehicle tank size, and the sensitivity of hydrogen supply to production and transportation logistics. Additionally, the temporal and spatial refuelling demand patterns of HFCVs differ from those of conventional vehicles, necessitating sophisticated modelling approaches to account for demand fluctuations, optimize refuelling schedules and ensure the seamless integration of hydrogen refuelling stations with renewable energy sources and local power grids121. Traffic simulations and data analytics have similarly been used in hydrogen infrastructure development. The former leverages agent-based models to replicate HFCV refuelling behaviour, providing a basis for evaluating refuelling infrastructure proposals122. The latter harnesses historical HFCV refuelling data to project future demand, informing strategic infrastructure deployment123. Beyond transport considerations, the strategic placement and dimensioning of refuelling stations within the energy network have been explored to mitigate potential negative impacts, such as system strain, or to facilitate the integration of renewable energy sources124.

Integrating transport and energy networks in the development of hydrogen refuelling infrastructure can address user refuelling needs and energy system limitations. For example, a strategic model for planning hydrogen refuelling infrastructure has been designed to harmonize the integration of HFCVs with renewable energy sources, considering HFCV optimal routing and refuelling choices to reduce hydrogen supply costs and travel time expenses125. With an ideal refuelling network configuration, HFCV users would not alter their travel or refuelling patterns. Furthermore, the coordination with renewable energy sources and energy storage solutions can increase the decarbonization of the entire framework.

China has emerged as the global leader in the deployment of hydrogen refuelling stations, with 250 operational sites as of April 2022 (ref. 126). Japan ranks second, with 161 hydrogen refuelling stations, aligning with the long-term commitment of the country to hydrogen as a core component of its energy strategy127. Japan’s leadership in this space is partly owing to the pioneering efforts of its automakers, such as Toyota and Honda, which are among the few selling HFCVs commercially128. These efforts are supported by a robust national strategy aimed at building a ‘hydrogen society’129, which includes substantial investment in infrastructure and research and development to overcome the cost and technological barriers associated with hydrogen production, storage and distribution130,131.

The expansion of hydrogen refuelling stations presents several logistical and regulatory challenges that can delay development. Land acquisition, for example, is often hindered by zoning restrictions and community resistance83. Moreover, in dense urban environments, such as those in Japan, space is limited for installing private residential refuelling options132. Permitting processes, which involve multiple stakeholders, add further delays, particularly in urban or densely populated areas88. Additionally, ensuring compliance with safety and environmental standards can extend timelines. On the regulatory side, the lack of harmonized policies and standards for hydrogen storage, distribution and refuelling poses barriers to expansion across regions. In Europe, regulatory and safety concerns from insurers can hinder station development133. However, with increasing government support and the rising adoption of HFCVs, investment in conventional and innovative refuelling technologies, including mobile refuelling units and on-demand hydrogen delivery, is increasing worldwide. The Hydrogen Mobility Europe project, underpinned by a €170 million demonstration initiative, receives substantial backing from the European Union134,135, underscoring a collaborative effort across Europe to enhance hydrogen refuelling infrastructure and contributing to the establishment of stations in locations including Germany, France and the UK136,137.

Scaling green hydrogen

The environmental benefit of HFCV integration hinges on the method of hydrogen production and its alignment with renewable energy sources. The greater the use of green hydrogen produced through electrolysis using renewable energy, the larger is the reduction in the well-to-wheel carbon footprint for HFCVs138. However, there are challenges to scaling the production of green hydrogen. Moreover, if the demand for hydrogen does not align with the availability of green hydrogen, the reliance on conventional hydrogen production methods, such as steam methane reforming, might lead to increased carbon emissions. This misalignment might also increase the demand for non-renewable energy sources. Therefore, it is imperative to foster synergy between HFCVs and renewable hydrogen production across both distribution and transmission systems to maximize the environmental benefits. In addition to green hydrogen, blue hydrogen — produced from natural gas with carbon capture and storage — also has a transitional role in the hydrogen economy (Box 1).

Renewable production facilities

Green hydrogen generation is increasingly decentralized, enabling HFCVs to be refuelled with hydrogen produced on-site at refuelling stations or from proximate green hydrogen facilities139. Refuelling stations can be outfitted with on-site renewable energy sources, such as solar or wind power, to produce green hydrogen through electrolysis. These stations can operate independently or be integrated into the existing energy grid for supplemental power, using energy storage solutions to balance the variability of renewable energy production and hydrogen demand140. The hydrogen produced is stored and made available for HFCVs, ensuring a sustainable and continuous supply. Japan is at the forefront of integrating renewable energy sources into its hydrogen refuelling stations. One of the most notable projects is the Fukushima Hydrogen Energy Research Field (FH2R), which features a 10-MW hydrogen production unit powered by renewable energy, making it one of the largest of its kind globally141. FH2R is designed to produce up to 1,200 Nm3 of hydrogen per hour, using electricity generated from solar panels. Centralized green hydrogen production has a complementary role in the future energy and transport systems, and it is suited for large-scale production and distribution. For example, Shell is constructing the largest renewable hydrogen plant in Europe with a 200-MW electrolyser, Holland Hydrogen I in the Netherlands, that is due to be operational in 2025 (ref. 142).

Challenges to large-scale production

Challenges to scaling the production of green hydrogen include cost and sustainability issues, such as water use, as well as potential spatiotemporal mismatches in hydrogen supply and demand. HFCVs have a key role in helping to align hydrogen demand with variable renewable energy supply, thereby facilitating the effective integration of green hydrogen into the energy and transport systems.

Production costs

Technological advances, industrial scaling and supportive policies are projected to reduce the cost of green hydrogen. Central to these cost reductions are breakthroughs in electrolyser technology. Innovations such as proton exchange membrane and solid oxide electrolysers have markedly increased the energy efficiency of green hydrogen production while reducing operational demands. NPMCs are also being developed to replace precious metals, offering comparable performance at a lower cost143. These developments, combined with modular191 and scalable electrolyser designs, enable flexible deployment and more efficient production processes across varying scales of operation. The rapid expansion of hydrogen infrastructure globally has also decreased production costs through economies of scale. The increased deployment of hydrogen technologies will drive improvements in the manufacturing efficiency of electrolyser and fuel cell systems, leading to reductions in the per-unit cost of green hydrogen. Equally important is the declining cost of renewable energy, which lowers the electrolyser operating costs. With all these advances, it is estimated that green hydrogen could achieve cost parity with fossil-derived hydrogen by around 2030 in regions with abundant renewable energy resources. Moreover, with the integration of intelligent scheduling systems, hydrogen production can be aligned with periods of surplus renewable energy generation, ensuring optimal use of renewable resources and minimizing electricity costs144.

Water use

Hydrogen production through electrolysis requires large amounts of water, approximately 9 l per kg hydrogen produced, which can raise sustainability concerns, particularly in regions where water is scarce. Alternative water sources, such as desalinated seawater or recycled wastewater, are required to reduce the reliance on freshwater resources. Advances in desalination technologies, including energy-efficient reverse osmosis and solar-driven systems, have enhanced the feasibility of these alternatives by lowering costs and increasing operational efficiency. Similarly, the integration of wastewater recycling processes within industrial hydrogen production facilities offers a sustainable pathway for water usage145. Emerging technologies, such as solid-oxide electrolysis cells, are also focused on increasing the water efficiency of electrolysis while maintaining hydrogen production efficiency146. Strategic co-location of hydrogen production plants with renewable energy projects in regions with sufficient water availability further mitigates water stress, reducing the need for extensive water transport infrastructure. Additionally, policies that promote sustainable water management in hydrogen production, such as water withdrawal limits in arid regions or subsidies for water-efficient technologies, can ensure the environmental viability of scaling green hydrogen production.

Supply and demand

Increases in green hydrogen production might challenge the stability of energy distribution systems, but this issue can be mitigated by scheduling hydrogen production to align with HFCV refuelling needs. This approach ensures a balanced demand for green hydrogen, thereby maintaining the integrity of the energy system147. For example, excessive green hydrogen production during peak periods of renewable energy generation could lead to storage and distribution challenges within the hydrogen network, potentially exceeding storage capacities or refuelling demand148. Strategically timing hydrogen production to also align with HFCV refuelling requirements (discussed further in ‘Aligning HFCVs with large-scale green hydrogen production’) can help manage these surpluses149. Likewise, the fluctuating nature of wind or solar power used for hydrogen production can lead to imbalances in hydrogen supply, affecting the predictability and consistency of hydrogen availability for refuelling. This variability necessitates flexible and responsive hydrogen production and storage strategies to accommodate changes in renewable energy generation, ensuring a stable and reliable hydrogen supply for HFCVs150.

Aligning HFCVs with large-scale green hydrogen production

Aggregated HFCVs, through strategic refuelling schedules or coordinated hydrogen production (that is, planning and controlling when and how much hydrogen is produced based on anticipated demand), can harmonize with green hydrogen generation, alleviating spatiotemporal mismatches in hydrogen supply and demand. This synchronization enables the effective use of renewable energy for hydrogen production, ensuring a stable hydrogen supply for HFCVs and enhancing the overall efficiency of the hydrogen and energy systems151.

Trading green hydrogen

Engaging in the energy market presents a strategy for aligning the refuelling demand of HFCVs with large-scale green hydrogen production. The cost of producing green hydrogen can be competitively low relative to fossil-based hydrogen when powered by surplus renewable energy152. Consequently, during periods of abundant green hydrogen production powered by surplus renewable energy, the cost of hydrogen could decrease, benefiting from the economics of overproduction. By purchasing hydrogen at these lower prices, aggregators of HFCVs can optimize refuelling strategies to minimize costs and encourage the use of renewable energy for hydrogen production, thus fostering a more sustainable energy landscape. The Hydrogen Council is a key organization in developing international standards for the hydrogen market, which includes around 150 multinational companies from various regions, including North America, Asia-Pacific, Europe and Africa. This organization aims to expand the hydrogen market and make it more efficient153; a key focus is on creating a reliable market for hydrogen through transparent trading practices and supportive policies facilitated by certification schemes154,155. This effort is important for making hydrogen purchases more strategic, which is essential for the growth of the HFCV market and the adoption of renewable energy sources for hydrogen production.

HFCV aggregators and green hydrogen producers can likewise form partnerships to engage jointly in energy markets. This collaboration enables renewable energy to be leveraged for hydrogen production, aligning supply with sustainable practices and market demands156. For example, flexibility in hydrogen production and storage can be used to stabilize the variability in renewable energy output. This approach mitigates market participation risks for green hydrogen facilities, enhancing their economic viability. Moreover, an integrated system of HFCVs and green hydrogen production can establish a ‘green hydrogen virtual power plant’ (GHVPP) that incorporates other assets such as renewable energy sources and energy storage solutions157. Through the coordinated management of HFCVs, green hydrogen production and supplementary resources, a GHVPP operates akin to a traditional power plant, participating in energy markets and potentially offering ancillary services, thus contributing to grid stability and sustainability.

Spatiotemporal coordination of HFCV refuelling

As mobile hydrogen consumers, HFCVs can address spatial and temporal mismatches in hydrogen supply and demand. Through judicious scheduling of HFCV refuelling, users can capitalize on periods of high green hydrogen production, leveraging geographic and temporal variations in hydrogen pricing158. This strategic refuelling can reflect in the locational marginal prices, illustrating the dynamic balance between supply and demand in the hydrogen market159. The potential for HFCVs, particularly in autonomous fleets, to be seamlessly integrated with green hydrogen production enhances the operational flexibility and efficiency of the HFCV fleet and broader hydrogen supply system, presenting an approach to optimizing renewable energy use within the transport sector.

Roadmap to HFCV integration

The integration of HFCVs into a sustainable energy and transport system requires a multifaceted approach that encompasses infrastructure development; innovative technologies for hydrogen production, storage and distribution; consideration of the environmental effects; and the implementation of economic incentives (Table 3).

Table 3 Roadmap for HFCV integration into a sustainable energy system
Full size table

Smart refuelling

In the initial stages of integrating HFCVs into the energy and transport system, refuelling relies on conventional and manually operated stations with limited adaptability. Progression to the next phase involves the adoption of smart refuelling technologies that integrate automation, monitoring and optimization tools to address the scalability needs of HFCVs. For example, AI-based systems for predicting hydrogen demand use machine learning algorithms to analyse historical and real-time data to enable dynamic scheduling and hydrogen allocation to meet fluctuating demand patterns. Such systems are already being piloted in some regions, such as California, where hydrogen station operators are collaborating with AI startups to refine demand forecasting models160. In parallel, IoT-enabled refuelling stations are being developed, featuring sensor networks that monitor hydrogen pressure, flow rates and temperature in real time. These data are fed into a central system for predictive maintenance, ensuring that the station operates reliably and safely. A pilot project by Toshiba in Japan has implemented such IoT technologies, with the proactive maintenance strategies leading to a 30% reduction in station downtime161. On-site hydrogen production is also central to smart refuelling. Compact electrolysers powered by on-site renewable energy sources enable refuelling stations to operate more independently, reducing reliance on centralized production hubs and complex, energy-intensive transport logistics. An example is the H2Ref project in Europe, which combines renewable energy sources with electrolysis at refuelling sites, lowering operating costs and reducing emissions. Cost considerations for smart refuelling systems vary depending on the components and scale. IoT-based monitoring systems cost approximately US$50,000–100,000 per station, whereas on-site electrolysers range from US$500,000 for smaller units to more than US$1 million for larger installations capable of producing several hundred kilograms of hydrogen per day162. AI-based demand forecasting systems add another US$20,000–50,000 for software development and integration. However, these costs are expected to decrease with broader adoption and economies of scale. Regions including the European Union and Japan are already progressing towards the incorporation of AI-based demand forecasting systems into new hydrogen refuelling station designs, supported by government incentives and private investment. For example, Shell and ITM Power are working on scaling green hydrogen production for stations across Europe by 2025, and similar initiatives are underway in South Korea under its Hydrogen Economy Roadmap163.

In addition to the deployment of smart refuelling technologies, advances in hydrogen production and storage technologies are required to increase the flexibility of refuelling systems, allowing for better alignment with renewable energy generation. In the ultimate stage of integration, fully automated hydrogen refuelling stations emerge, serving not only as refuelling points but also as dynamic components of the broader energy network.

Essential infrastructure

The integration of HFCVs into the sustainable energy landscape necessitates comprehensive infrastructure, encompassing hydrogen refuelling stations and information and communication networks. These elements are pivotal for facilitating efficient hydrogen distribution, enabling real-time data exchange and ensuring the interoperability of HFCVs within the energy system.

Refuelling infrastructure

Initial strategies for HFCV refuelling infrastructure planning primarily aimed to meet user refuelling needs, mitigate the potential impact of supply variability on hydrogen supply chains, and enhance the integration of green hydrogen production164. To overcome the challenges associated with expanding hydrogen refuelling infrastructure, a phased development strategy is required. In the short term, government-led pilot projects and targeted subsidies can help establish initial stations in high-demand areas. For example, lessons from the ‘Basic Hydrogen Strategy’ of Japan, which prioritizes urban hubs and industrial zones, offer a valuable blueprint for early deployment. Medium-term efforts should focus on scaling infrastructure using modular hydrogen refuelling stations, which lower upfront capital costs and enable flexible, location-sensitive deployment. These modular systems can be co-located with transportation corridors to minimize disruption and improve resource allocation. In parallel, AI-based demand forecasting systems can be used to predict spatial and temporal refuelling needs, informing dynamic station siting and network planning. Long-term strategies should emphasize the development of a global hydrogen trading network, supported by international collaboration to harmonize standards and facilitate cross-border hydrogen transport. HFCVs are becoming increasingly interoperable across regions, aided by the convergence of tank pressure specifications (typically 350 bars or 700 bars), nozzle standards and communication protocols at hydrogen refuelling stations, which ensures compatibility across diverse infrastructure settings. Emerging technologies such as geographic information systems, IoT and real-time optimization platforms can further refine infrastructure planning by incorporating predictive insight into supply chain coordination. The integration of AI-powered forecasting with strategic planning and robust policy frameworks will be essential to achieving the scalable and sustainable growth of hydrogen refuelling infrastructure.

Moreover, hydrogen refuelling stations are typically envisioned to have a lifespan of 15–20 years. However, the potential for HFCVs to contribute to energy systems, especially through concepts such as hydrogen back-feeding or power-to-gas, often remains underexplored owing to the nascent stage of such business models165. Consequently, many existing refuelling facilities might not fully support these advanced functionalities. It is, therefore, crucial to develop refuelling infrastructure that not only addresses current refuelling demands but that is also adaptable to future advances in hydrogen energy utilization and integration.

Information and communication infrastructure

Comprehensive sensor networks are required to align HFCV refuelling activities with green hydrogen production. These sensors will track the real-time status of HFCVs, hydrogen refuelling stations and hydrogen production facilities166. To precisely manage HFCV refuelling schedules for optimal hydrogen usage, the frequency of data collection and communication must be nearly instantaneous. This rapid exchange of information places additional demands on specialized communication systems, which are typically segregated from general public networks to ensure efficiency and security in data handling167. Hence, the development of cost-effective and high-performance information and communication infrastructure is crucial. Furthermore, as HFCVs become more prevalent, potential vulnerabilities in cyber-physical security could emerge, necessitating that these systems exhibit robust cyber resilience to protect against threats and ensure the integrity of the hydrogen supply chain168.

Coupling between HFCVs and the energy system

Integrating HFCVs into the broader energy system represents a shift in how energy is produced, stored, distributed and consumed. Rather than being passive consumers, HFCVs are envisioned as active, mobile nodes in future energy networks. The systemic integration of HFCVs must follow a phased roadmap aligned with technological maturity, infrastructure readiness and regulatory support, ultimately enabling bidirectional energy exchange, renewable energy use and grid resilience. In the initial phase, the focus lies in establishing unidirectional coupling through hydrogen consumption. HFCVs create localized demand for hydrogen, incentivizing investment in renewable energy-powered electrolysers. These electrolysers can convert surplus electricity from wind and solar power into hydrogen, storing renewable energy over long durations and mitigating curtailment (whereby excess renewable energy is wasted owing to grid constraints). This phase lays the foundation by anchoring HFCVs in regional hydrogen economies and promoting flexible hydrogen production tied to renewable availability. The second phase emphasizes dynamic interaction between HFCVs and the electrical grid through bidirectional vehicle-to-grid (V2G)165 systems. Once V2G infrastructure is deployed and regulatory frameworks are in place, HFCVs can serve as decentralized energy storage units. Through hydrogen refuelling, HFCVs can absorb excess electricity during periods of low-demand or high renewable energy generation and discharge it during peak load conditions or shortfalls. This temporal balancing capacity helps to stabilize grids with a high penetration of variable renewables. In the advanced phase, HFCVs are integrated into hybrid energy systems alongside batteries, acting as mobile dispatchable resources that enhance grid flexibility. Batteries provide short-duration, high-efficiency energy storage, whereas hydrogen systems address long-duration and seasonal storage needs. In this hybrid context, HFCVs provide backup energy during extended renewable lulls, assist with peak shaving, and offer ancillary services159,169 such as frequency regulation and voltage support. The mobility of HFCVs allows for real-time spatial deployment of flexible energy services, particularly in remote or distributed energy systems170,171.

Innovation in the technical integration of HFCVs into the broader energy system is offering insight into the diverse roles these vehicles can have beyond mobility. For example, a vehicle-to-vehicle172 charging concept has been proposed, whereby HFCVs support EVs by supplying energy through a decentralized sliding-mode control strategy. This approach also demonstrates how HFCVs can complement battery EVs by providing greater range and flexible energy services, particularly in applications in which EVs face limitations (Box 2). A dual-functional single-stage PEMFC system has also been designed to minimize harmonic distortion and reduce component complexity in grid-connected EV charging systems173. This configuration increases the overall system efficiency and supports smoother integration of HFCVs with the grid. A third example is a coordinated operation strategy for a PEMFC–grid interface174, whereby the fuel cell system can dynamically inject or absorb power to support grid stability while managing its own refuelling needs. These examples underscore the potential of HFCVs to interact with electricity networks in flexible, responsive ways and exemplify emerging pathways through which HFCVs could be integrated into a more distributed, multi-functional and resilient energy infrastructure.

Modelling and optimization

Models and optimization strategies are required to improve the coordinated operation, energy management and market participation of large-scale HFCV fleets within a sustainable hydrogen and energy system.

Modelling HFCV refuelling behaviour

Active participation of HFCVs in hydrogen production and distribution processes can introduce complexities in managing hydrogen storage and can affect the efficiency of the hydrogen supply chain, making it is essential to assess the impact of HFCVs on hydrogen production, storage efficiency and distribution networks66. User behaviour, including refuelling frequency and patterns, dictates the operational dynamics of HFCVs and the demand on hydrogen infrastructure. However, these patterns are difficult to predict and vary widely. Consequently, sophisticated forecasting techniques are needed to accurately anticipate HFCV refuelling demands. Data-driven AI algorithms are emerging as effective tools for predicting HFCV user behaviour and can increase the efficiency of hydrogen distribution strategies175.

For hydrogen market participation, an HFCV aggregator might need to manage the refuelling requirements of thousands of HFCVs. Owing to the computational complexity of modelling the specific needs of each HFCV, aggregate models are required to represent the collective demand and behaviour of large-scale HFCV fleets151. Characterization of the collective refuelling dynamics of an HFCV fleet using generalized aggregate metrics, such as total hydrogen demand and refuelling patterns, reduces the complexity of the model and increases the computational speed. Nevertheless, this simplification could compromise precision, potentially leading to inaccuracies in hydrogen supply management156. Striking an optimal balance between the efficiency and accuracy of modelling for large-scale HFCV fleets warrants further investigation.

HFCV operation

Managing and directing many HFCVs to ensure efficient hydrogen use or to support green hydrogen production is challenging. Operators need to coordinate the refuelling needs of a diverse fleet of HFCVs and match them with the available hydrogen supply176. The complexity of handling such a task with a single, centralized system is too high, indicating a need for more decentralized or distributed approaches to manage the process. With decentralized and distributed strategies, operational decisions are made at the refuelling station or at the individual HFCV level, using data exchanged between the operator and the vehicles177. This approach lowers the computational load but can increase the demand on communication systems and might not be optimal with very large fleets. An effective solution is to use a hierarchical system that combines elements of centralized and decentralized management, with the aim of managing the trade-offs between computational demands and communication needs178.

The operation of HFCVs faces unavoidable uncertainties, such as user refuelling habits, variability in green hydrogen production, and fluctuations in market pricing179. Methods such as stochastic programming, robust optimization, chance-constrained programming and model predictive control can be applied180 to tackle these uncertainties and to enable more informed decisions to be made regarding when, where and how much hydrogen each HFCV should refuel, how hydrogen supply should be managed to meet fluctuating demand, and how to balance cost, reliability and environmental goals in real time. However, these approaches typically need extensive historical data to model uncertainties accurately, which might not always be accessible, or they might be too cautious, such as underestimating the flexibility of HFCV refuelling capabilities181. Managing and controlling HFCVs also involves navigating requirements and limitations imposed by hydrogen supply systems and transportation infrastructure, such as limited refuelling station capacity or restrictions on the transport of hydrogen. AI algorithms based on data analysis have demonstrated potential in addressing these challenges182.

Policy and incentive frameworks

As HFCVs become increasingly embedded in the hydrogen economy, robust policy support, well-structured incentive mechanisms, innovative business models and the development of new hydrogen markets are essential to align technological advances with market uptake and system-wide sustainability.

Incentives and regulations

Incentives such as dynamic hydrogen pricing, which involves adjusting rates based on renewable energy generation profiles, are being explored to encourage vehicle refuelling during periods of surplus renewable energy, thereby improving economic efficiency and grid alignment183. Complementing these operational strategies, financial instruments such as green bonds can be used to attract investment into hydrogen infrastructure, including electrolyser deployment, refuelling stations and vehicle fleets. These bonds channel capital into environmentally beneficial projects, aligning investor interests with long-term climate goals184. In addition, targeted subsidies, tax credits and low-interest loans can help lower the initial cost barriers for consumers and developers, supporting early adoption and infrastructure build-out. Incentives for co-located refuelling hubs, grid-integrated hydrogen production facilities, and demand-side participation (for example, V2G services) can further facilitate system-level integration185. To support interoperability and coordination, regulatory frameworks should also address standardization of hydrogen purity, pressure levels and digital protocols for grid interaction.

Business models

To date, the focus of development efforts has primarily been on increasing the efficiency of hydrogen refuelling infrastructure. The practicality of deploying HFCVs for hydrogen storage and back-feeding into the hydrogen supply chain is under review186. Evaluating the effects of these activities on the efficiency of the hydrogen supply chain and establishing fair compensation models for users remain challenges in developing business models for HFCV integration. Additionally, using HFCVs for hydrogen redistribution could affect vehicle warranties187. At present, the concept of leveraging vehicles as mobile hydrogen sources is being explored only in niche scenarios, such as providing hydrogen for applications in remote areas without established hydrogen infrastructure. If HFCVs begin to have a more active role in supporting the hydrogen economy in the future, concerns regarding the impact of frequent refuelling and hydrogen supply activities on vehicle longevity might arise, similar to the effects of regular driving, which could have implications for vehicle warranties188. To maximize the benefits of HFCVs, an innovative business model that addresses these concerns is needed. A potential approach could involve guaranteeing a certain number of hydrogen refuelling cycles rather than focusing solely on vehicle mileage, offering a warranty structure that more accurately accounts for the role of HFCVs in hydrogen distribution and usage64.

New hydrogen markets

Current hydrogen markets are primarily structured for conventional supply and demand dynamics. To foster innovation and inclusion, policymakers are encouraged to reconfigure these markets to welcome new entrants, such as HFCV fleets or hydrogen production collectives. This market framework should accommodate distributed, smaller-scale hydrogen sources, enabling them to participate collectively, similar to how distributed energy resources engage in electricity markets189. Additionally, hydrogen markets at the local level must be established; these distributed markets are essential for creating opportunities for HFCVs to contribute to the local hydrogen supply chain and support integration with local green hydrogen production. Germany’s National Hydrogen Strategy exemplifies the necessary steps to cultivate such a market. This strategy emphasizes the importance of bolstering domestic hydrogen production capabilities, with an ambitious target to augment domestic electrolyser capacity to 10 GW by 2030, and increasing hydrogen imports. This strategic direction underscores the necessity of reconfiguring hydrogen markets to support distributed, smaller-scale production sources. Distributed hydrogen production and regionalized imports enable a decentralized market structure by bringing supply closer to demand and supporting localized storage and distribution systems. Enabling small-scale hydrogen producers to participate collectively paves the way for a more inclusive and innovative hydrogen economy. Such an approach not only facilitates the integration of HFCVs into the local supply chain but also promotes the use of local renewable energy sources, thereby enhancing the overall sustainability and resilience of the energy landscape190.

Outlook

The advancement of hydrogen technologies is poised to reduce their costs and enhance their operational performance, as well as to facilitate the broader deployment of HFCVs. Ongoing innovation in catalyst materials and electrolyser design continues to drive down the cost of green hydrogen, bringing it closer to price parity with fossil fuels. Concurrently, improvements in hydrogen storage and fuel cell systems are enabling higher energy densities, greater efficiency and longer vehicle range. These developments support the transition to HFCVs across sectors such as heavy-duty transport and industrial logistics. In parallel, the growing integration of AI and IoT technologies into hydrogen systems is unlocking opportunities for predictive diagnostics, dynamic operational control and optimized system resilience. These tools can complement existing infrastructure by enabling real-time refuelling coordination and adaptive supply chain management, as well as enhancing the reliability of hydrogen delivery networks.

Despite this momentum, challenges remain. The large-scale integration of HFCVs requires robust communication systems, scalable infrastructure and harmonized standards for cross-regional interoperability. Strengthening cyber-physical system security and developing cost-effective data platforms will be essential to ensure trust, efficiency and resilience as the hydrogen transport ecosystem expands. Looking ahead, continued collaboration between stakeholders — including industry, government and academia — will be crucial to overcoming the remaining barriers and in supporting a flexible, secure and sustainable hydrogen mobility system, as well as enabling the seamless integration of HFCVs and hydrogen technologies into the broader energy system191.