Hydrogen Distribution Research Articles

Investigations of combustion characteristics and mechanism of backfire-induced super-knock in a turbocharged hydrogen engine

Hydrogen internal combustion engines have been demonstrated to offer high power with zero carbon emissions. However, knock pose a significant obstacle to enhancing hydrogen engine performance further. Super knock commonly occurs in highly boosted engines with low-speed pre-ignition regimes while a critical super-knock induced by backfire with a new mechanism is detected in hydrogen engines. Experiments and multi-cycle numerical simulations are conducted on a 5.13 L port fuel injection turbocharged hydrogen engine. The results indicate that backfire leads to a maximum pressure amplitude oscillation of 134.7 bar super-knock in the next cycle, which is attributed by twice auto-ignition at -1.3/3.6 °CA. Backfire rises the local temperature to 915 K at the bottom of the cylinder and scrambled hydrogen distribution, leading to large locally rich regions of lambda=1.2, a lean mixture of lambda=2.9 near the spark plug, results in 5.4×10-4/2×10-3 maximum mass fraction of HO2/H2O2. The mechanism of super-knock induced by backfire and normal knock caused by advanced ignition are compared, the unburned region size is positively correlated with the knock intensity. This study of super-knock induced by backfire mechanism is first proposed and it reveals insights of avoiding super-knock, thereby achieving higher performance hydrogen engines.

Control strategy of reducing hydrogen enrichment in heat-affected zone during welding for ultra-high strength steels

The hydrogen diffusion behaviors in welded joints of ultra-high strength steel (UHSS), which are related to hydrogen-induced cracks (HIC) in welding, are not yet fully understood due to the lack of in-situ observation techniques for hydrogen during welding. An improved microphotography technique is proposed to visualize the hydrogen distribution within the as-welded joint. When UHSS is welded using traditional welding materials, the transformation temperature from γ to α phase (TF) of the weld metal (WM) is higher than that (TB) of the heat-affected zone (HAZ), resulting in the observed hydrogen enrichment in the HAZ. We developed a low transformation temperature (LTT) welding material. This material is designed so that the TF of WM is lower than the TB of HAZ, facilitating hydrogen back-diffusion from the HAZ to the WM. This back-diffusion effectively reduces the hydrogen concentration in the HAZ. Additionally, a thermo-mechanical hydrogen diffusion sequentially coupled finite element procedure was utilized to simulate hydrogen concentration evolution during welding, revealing the control process of phase transformation temperature differences (ΔT = TF - TB) on hydrogen diffusion behavior and the influence of residual stress on the accumulation of hydrogen. The microphotography technique has successfully validated these findings, which can help to mitigate the risk of HIC in the HAZ during welding of UHSS.

An in-situ investigation of microstructure neighborhood effects on hydrogen-induced dislocation activity

The interactions between hydrogen and crystallographic defects are the key to understanding hydrogen induced localized plasticity or damage mechanisms. However, unraveling such interactions based on the resulting mechanical effects alone can be challenging, due to the spectrum of various effects hydrogen can create in a given microstructure. Pre-deformation or post-mortem characterization of hydrogen segregation has similar limitations, as they can only provide snapshots of these complex processes with challenging spatial and temporal scales. To tackle this, we design in situ experiments that combine electron channeling contrast imaging (ECCI), electron backscattered diffraction (EBSD), and desorption spectroscopy, to investigate hydrogen defect interactions, under no external loading. We show that the inhomogeneous hydrogen distribution within microstructures can cause long-range (>200 nm) dislocation rearrangements. Interpretation of these results as manifestations of boundary-segregation induced stress suggests that microstructural characteristics on either side of the boundary should also play an important role. We provide quantitative assessments of these microstructure neighborhood effects and discuss additional contributions from hydrogen-induced changes in stacking fault energy and elastic modulus.

Microstructure evolution and hydrogen absorption characteristics of gradient-hydrogenated Ti-4.5Al-3V-2Mo-2Fe alloys

Ti-4.5Al-3V-2Mo-2Fe rolled material is a dual-phase titanium alloy with an average grain size of less than 3 μm; its optimal superplastic forming temperature of 760 °C is at least 50 °C lower than the temperature required for diffusion bonding, making it challenging to carry out superplastic forming/diffusion bonding within a process window. The promotion of hydrogen on the low-temperature diffusion bonding of the alloy was verified through thermohydrogen processing, and the absorption characteristics of hydrogen in the alloy at various temperatures, holding times, and pressures were investigated. Subsequently, a mathematical model for achieving standardized hydrogen content was developed. X-ray polycrystalline diffractometer (XRD) analysis was utilized to preliminarily explore phase differences in samples with varying levels of hydrogen content. Furthermore, scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron back scatter diffraction (EBSD) and time of flight secondary ion mass spectrometry (TOF-SIMS) were employed to analyze microstructure changes and hydrogen distribution in both the surface and core regions of the titanium alloy following hydrogenation, demonstrating its feasibility for surface hydrogenation treatment of titanium alloy sheets

Renewable energy in sustainable cities: Challenges and opportunities by the case study of Nusantara Capital City (IKN)

Indonesia's future IKN capital might be sustainable, low-carbon, and climate-resilient. The Low Emissions Analysis Platform (LEAP) simulates energy efficiency in various demand sectors, renewable energy, and sustainable transportation solutions. Sustainable cars, such as renewable-energy-powered electric and green hydrogen-powered vehicles, can reduce energy consumption by 43% in 2045 and 33% in 2060, respectively, compared to BAU. GHG emissions per capita will drop 70% in 2045 and 63% in 2060. In the net-zero emission (NZE) scenario, IKN can reach 100% green energy by 2045 with a 4.4 GW solar power plant, a 0.92 GWh BESS, and a full load hour capability of 4 hours. We will use 1.1 GW of hydropower and 143 MW of wind power by 2045. In 2060, hydropower will be 2.8 GW, wind power will be 184 MW, and solar power will be 8 GW with 1.6 GWh of BESS. Lack of legislation, technical expertise, high prices, inadequate grid infrastructure, and insufficient renewable electricity restrict BESS use in Indonesia. Solar energy installation requirements, subsidies, and off-grid project incentives can all help ease BESS use. Forecasts predict 0.53 GW of rooftop solar PV capacity by 2045 and 3.35 GW by 2060. Net metering and solar tariffs boost rooftop solar system profitability. One ton of green hydrogen production requires 55.7 MWh from a solar power plant. Solar power plant capacity will rise to 0.49 GW by 2045, producing 19,359 tons of green hydrogen, and almost quintuple to 89,594 tons by 2060. Hydrogen generation, storage, transit, and distribution require specific infrastructure due to high capital costs and a lack of networks, yet interest in them is growing.

Artificial Intelligence based Leak Detection in Blended Hydrogen and Natural Gas Pipelines

In the transition towards a hydrogen-based energy system, the strategic use of pipelines is crucial for efficient hydrogen distribution. Leveraging existing natural gas pipelines to carry a mix of hydrogen and natural gas offers a cost-effective alternative to building new infrastructure. This study explores the development of a leak detection system compatible with existing pipelines, specifically tailored for the blended hydrogen and natural gas mix. Given the scarcity of leak data for blended hydrogen-natural gas pipelines, the study introduces a Real-Time Transient Model (RTTM) for blended gases, simulating leak dynamics to generate necessary data. Additionally, a leak detection system (LDS) is developed using a fusion of Convolutional Neural Network (CNN) and Explainable Artificial Intelligence (XAI) through Adaptive Neuro-Fuzzy Inference Systems (ANFIS). This LDS framework overcomes the “black box” issue common in AI-driven systems, enabling reliable detection. The integration of Explainable and traditional AI techniques holds promising implications for blended hydrogen pipelines by enhancing the safety and efficiency of hydrogen transportation, thereby mitigating economic and environmental impacts, and addressing public concerns.

A Radial Memetic Algorithm to Resolve the No-Wait Job-Shop Scheduling Problem

A new radial memetic algorithm is proposed to resolve the no-wait job-shop scheduling problem. Basically, each sequencing solution is factorized as a distance-based ranking model, i.e., each solution is decomposed in n − 1 terms, where n is the number of jobs to be sequenced. After that, a cumulative radial distribution of hydrogen is considered to produce new factorizations using the offspring information (genes). Such radial distribution is applied in the local optimization procedure of the memetic algorithm. A benchmarking dataset is used to show the performance of this new experimental technique, as well as other current procedures. Statistical tests were implemented to confirm the performance of the proposed scheme.

Photothermal‐Mediated In Situ Delivery of Polycations Into Bacteria via Alternating Polymer‐Modified Nanoparticles for Targeted Bacterial Killing and Enhanced Biofilm Penetration

AbstractTo achieve targeted clearance of bacteria and their biofilms, a straightforward strategy to integrate antimicrobial alternating polymers with photothermal polydopamine nanoparticles (PDA NPs) is proposed. By manipulating the alternating distribution of electrostatic, hydrophobic, and hydrogen bonding units in the polymer backbone, the thermal stability of polymer‐particle interaction can be tuned, enabling photothermal‐mediated in situ delivery of cationic antimicrobial polymers into bacteria. The alternating polymer coating significantly enhances the penetration capability of NPs into the Methicillin‐resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) biofilm, achieving a 99% bactericidal rate within the biofilm at a low concentration after 10 min of near‐infrared irradiation, whereas pristine PDA NPs shows negligible effects. The in‐vitro co‐culture model demonstrates that alternating‐polymer‐loaded NPs selectively eradicate 1 × 107 CFU mL−1 of MRSA and E. coli while preserving over 75% viability of the mammalian cells, including mice fibroblasts, human kidney cells, human cervical cancer cells, and macrophages. The efficacy of these biocompatible NPs in targeting bacteria is further validated in a mouse MRSA‐infected wound model. This approach represents a significant advancement in developing safe and efficient antimicrobial therapies with targeted bacterial killing and minimal off‐target effects based on alternating cationic polymers.

Analysis of hydrogen-induced cracking mechanism in quenching and partitioning steels

Quenching and partitioning (Q&P) steels are extensively used in the automotive industry due to their exceptional strength and ductility. However, the impact of hydrogen embrittlement (HE) poses a huge challenge to the safe service of Q&P steels, highlighting the necessity to investigate the hydrogen-induced cracking mechanisms. This study investigates the hydrogen-induced failure mechanisms in Q&P steels through experiments and finite element simulations, focusing on microstructure, local stress heterogeneity, hydrogen distribution characteristics, and hydrogen-induced cracking. The results reveal that hydrogen cracking nucleation in Q&P steel is primarily due to the further accumulation of hydrogen in local high-stress martensitic/austenitic regions.

A Preliminary Methodological Framework of the Potential Hydrogen Economy for a Sustainable Transport in Malaysia

The transition to a hydrogen economy is vital for achieving sustainable transport in Malaysia, particularly in mitigating the environmental impact of heavy-duty mobility. This paper proposes a preliminary methodological framework to evaluate hydrogen's potential as a transformative solution for decarbonizing the transportation sector, focusing on key areas such as hydrogen production, storage, distribution, and vehicle integration, with an emphasis on green hydrogen from renewable sources. Our assessment reveals the significant potential of hydrogen to reduce greenhouse gas emissions and air pollutants, positioning it as a viable alternative to fossil fuels and battery-electric vehicles, especially in heavy-duty applications. The study assesses the technological feasibility, economic viability, and environmental benefits of adopting hydrogen in Malaysia, considering current infrastructure, production capabilities, and regulatory frameworks. Key challenges identified include the high costs of hydrogen production and infrastructure, technological barriers in storage and vehicle integration, and gaps in policy and market readiness. To address these, we propose strategic recommendations for stakeholders, highlighting the need for government support, public-private partnerships, and international collaborations. This framework aims to guide Malaysia’s transition to a hydrogen-powered transport sector, aligning with the nation’s sustainability and energy security goals while positioning Malaysia as a leader in hydrogen technology in Southeast Asia.

Ordering-facilitated lower hydrogen embrittlement sensitivity in a prototype high-entropy alloy

The ageing treatment (450 °C/60 h) led to the spinodal decomposition at grain boundaries (GBs) and the development of chemical short-range orders (CSROs) in the alloy matrix, increasing the strength and effectively reducing the HE sensitivity of the equiatomic FeMnNiCoCr alloy. Firstly, the emergence of NiMn- and Cr-rich orders at GB regions reduces hydrogen diffusion rates along GBs and limits hydrogen enrichment at these sites. Secondly, CSROs promote hydrogen accumulation within the grain interior and impede hydrogen penetration, resulting in a shallower hydrogen-affected depth in the aged sample. Moreover, the modulation of hydrogen distribution by microstructure initiates transgranular cracking in the aged sample.

Numerical Modeling of a Polymer Electrolyte Membrane Fuel Cell for Electric Aircraft Propulsion

Electrified propulsion systems with hydrogen-fueled fuel cells can potentially reduce carbon dioxide emissions from aircraft. However, achieving a substantial increase in the gravimetric/volumetric power density of fuel cell systems poses a considerable challenge. In this study, we focus on high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) working between 100 and 200°C. To design an optimized PEMFC structure for an electric aircraft, we have developed a numerical model that employs the finite element method (FEM) (COMSOL Multiphysics) to couple electrochemistry, gas diffusive and convective transports, and heat transfer in fuel cell components such as separators, gas flow channels, gas diffusion layers, catalyst layers, and a PEM. We thereby derive the current distributions associated with three-dimensional hydrogen, oxygen, and water vapor concentration distributions, as well as temperature distributions. Moreover, we develop a machine learning model from the data outputs of the FEM model, which serves as training data, to reduce the computational costs for the fuel cell stack design incorporated in a system-level numerical model.

Numerical Modeling of a Polymer Electrolyte Membrane Fuel Cell for Electric Aircraft Propulsion

Electrified propulsion systems with hydrogen-fueled fuel cells can potentially reduce carbon dioxide emissions from aircraft. However, achieving a substantial increase in the gravimetric/volumetric power density of fuel cell systems poses a considerable challenge. In this study, we focus on high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) working between 100 and 200°C. To design an optimized PEMFC structure for an electric aircraft, we have developed a numerical model that employs the finite element method (FEM) (COMSOL Multiphysics) to couple electrochemistry, gas diffusive and convective transports, and heat transfer in fuel cell components such as separators, gas flow channels, gas diffusion layers, catalyst layers, and a PEM. We thereby derive the current distributions associated with three-dimensional hydrogen, oxygen, and water vapor concentration distributions, as well as temperature distributions. Moreover, we develop a machine learning model from the data outputs of the FEM model, which serves as training data, to reduce the computational costs for the fuel cell stack design incorporated in a system-level numerical model.

Green Hydrogen Production From Non-Traditional Water Sources: A Sustainable Energy Solution With Hydrogen Storage and Distribution.

Green hydrogen development plays an essential role in creating a sustainable and environmentally conscious society while reducing reliance on traditional fossil fuels. Proton Exchange Membrane Water Electrolysers (PEMWEs), are sensitive to water quality, with various impurities impacting their efficiency, the quality of the hydrogen produced, and the device's lifespan. High-purity water is required for PEM electrolyzers; Type II water, which is required for commercial electrolyzers, must have a resistivity greater than 1 MΩ cm, sodium, and chloride concentrations less than 5 μg/L, and total organic carbon (TOC) content less than 50 parts per billion. The majority of electrolyzers operate on freshwater, or total dissolved solids (TDS) <0.5 g/kg, whereas brackish, rainwater, wastewater, and seawater have TDSs of 1-35 g/kg, 0.01-0.15 g/kg, 0.5-2 g/kg, and 35-45 g/kg, respectively. This critical review offers, for the first time, a comprehensive overview of relevant impurities in operating electrolyzers and their impact. The findings of this study indicate that electrolysis-based H2 processes are promising options that contribute to the H2 production capacity but require improvements to produce larger competitive volumes. In addition, the main challenges and opportunities for generating, storing, transporting, and distributing hydrogen, as well as large-scale adoption are discussed.

Laered composite hydrogenated films of zirconium and niobium: method of production and control of properties by thermopower method

In this work, to obtain layered materials with the inclusion of hydrogen, Nb/Zr films with different numbers of layers from 50 to 100 were used. The films were sputtered onto a silicon substrate using the vacuum-magnetron method in a specialized installation. The film thickness was varied from 10 to 50 nm. The resulting material was hydrogenated with protons on a TPU electrostatic generator with an energy of up to 1,2 MeV. The optimal modes for deposition of nano-sized metal multilayer Zr/Nb systems have been determined: for a Zr target, the specific power of the sputtering system is 37,9 W/cm2, for a Nb target — 26,4 W/cm2. A coating with clear boundaries between the individual layers of zirconium and niobium was obtained. It is shown that the optimal modes for studying nano-sized Zr/Nb layers are pressure 700 Pa, power 40 W, frequency 2 kHz, plasma fill factor 12,5 % for coatings with a thickness of individual layers of 100 nm. For coatings with individual layer thicknesses from 10 to 50 nm, the optimal pressure is 650 Pa, power 40 W, frequency 1 kHz. To control properties, the thermopower method is used. It was revealed that after proton irradiation there is an intensive accumulation of hydrogen atoms near the interfaces, which entails a change in the thermopower up to an inversion of its sign. The hydrogen distribution is predominantly bimodal, with local maxima in hydrogen concentration observed at the Nb/Zr interface, and the accumulation at the Zr/Nb interface is significantly lower. Hydrogen localization near the interfaces occurs predominantly in the vicinity of zirconium.

Comparing PEMFC state-of-health characteristics obtained by Galvanostatic Charge Method with and without nitrogen flush

Onboard determination of state-of-health (SoH) parameters becomes increasingly important with tightened lifetime requirements for automotive polymer electrolyte membrane (PEM) fuel cell systems. One way to electrochemically characterize SoH parameters like active catalyst surface area (roughness factor, RF), double layer capacitance and membrane permeability is the nitrogen-flush-requiring Galvanostatic Charge Method (GCM). In this publication, a nitrogen-flush-free and thus, onboard-compatible adapted version of GCM (AGCM from Möller et al. (2023)), is directly compared to its original method, GCM. A 20-cell automotive shortstack was frequently characterized with both GCM and AGCM methods as well as standard Cyclic Voltammetry (CV) during a degradation test. Additionally, the evaluation model for AGCM was varied in two aspects: Firstly, modeling the hydrogen partial pressure difference (ΔpH2) responsible for hydrogen crossover and secondly, modeling hydrogen diffusion in the cathode volume with a 0-D transport model. The characterization results prove that all investigated model variations of AGCM can reproduce double layer capacitance results from GCM and CV, as well as the decreasing trend in roughness factor results. RF-values characterized by AGCM agree with either GCM or CV results, depending on the evaluation model. A thorough analysis revealed the neglected short circuit resistance in combination with the chosen modeling approach of ΔpH2 in AGCM as the reason. The two modeling approaches for ΔpH2 base on extreme assumptions about the homogeneity of hydrogen distribution in the anode volume. Neither of them could reproduce the membrane permeability of GCM. Instead, one overestimates, one underestimates it, indicating the truth to be in between the two extreme models. However, AGCM measurement conditions are identified as a lever to improve the AGCM permeability results and their robustness, even if the modeling approaches remain unchanged. Furthermore, this study showed that neglecting hydrogen diffusion in the cathode volume in the AGCM evaluation model leads to overestimation of the membrane permeability.

Research on hydrogen distribution characteristics in town hydrogen-doped methane pipeline

The study of hydrogen concentration distribution law of hydrogen-doped methane pipeline is directly related to the safety and stability of hydrogen-doped methane pipeline network. Based on the theory of fluid dynamics, this paper established a model of hydrogen-doped methane pipeline and simulated the operation and shutdown status of hydrogen-doped methane pipeline by adopting the computational fluid dynamics method and selecting the mixture multiphase model and standard k - ε turbulence model. This paper investigates the hydrogen concentration distribution law in hydrogen-doped methane pipelines as well as the influence law of different hydrogen-doping ratios, operating flow velocities, operating pressures, shutdown time and gas usage on the hydrogen concentration distribution in gas pipeline. The results show that: under the operation condition, there is a weak uneven distribution of hydrogen in the pipeline, the hydrogen-doping ratio, flow velocity, pressure on the hydrogen volume fraction of the change in the 0.9% or less, the effect can be ignored; in the shutdown status, there is a clear stratification phenomenon, the hydrogen-doping ratio increased from 10 to 25%, the change in the volume fraction of hydrogen in the 11.2% or less, a positive correlation; with the extension of the shutdown time to 900s, the pipeline firstly appeared obvious stratification phenomenon in the branch pipe, the thickness of the gas with hydrogen volume fraction above 40% on the upper wall surface of the branch pipe increased to 0.7 mm, and after the shutdown time was extended to 10 h, obvious stratification phenomenon appeared in the main pipeline, and the volume fraction of hydrogen near the top of the main pipe of about 16.5 mm was above 30%, which was positively correlated; In the shutdown status, the shutdown time has the greatest effect on the stratification phenomenon in the pipe, followed by the hydrogen-doping ratio, and the gas usage has the least effect.

Research on hydrogen distribution of electroless nickel plating on aluminum-based silicon carbide composites

Abstract Aluminum-based silicon carbide composite materials have the characteristics of high thermal conductivity, low thermal expansion, and good dimensional stability. Therefore, the composites are widely used in space microwave component shell products. In order to meet the functional requirements of conductivity, welding, and heat dissipation when applied to antenna microwave components, aluminum-based silicon carbide composite materials need to be chemically plated with nickel, which introduces hydrogen, thus requiring research on hydrogen release and control. Here, SEM, XRD, and other methods are used to characterize the microstructure of aluminum-based silicon carbide substrate and nickel plating layer. There are certain pore structures in both the substrate and plating layer, providing a place for hydrogen storage. The experimental method of hydrogen microprinting has been used to characterize the distribution of hydrogen. The results showed that the hydrogen distribution pattern in aluminum-based silicon carbide nickel plating is as follows: after nickel plating on aluminum-based silicon carbide, hydrogen is distributed in the nickel plating layer and the shallow substrate under the coating; with the extension of time, hydrogen spontaneously diffuses to the deep substrate; hydrogen is mainly distributed in the Al matrix and less on SiC particles.

Thermodynamic performance assessment of the four-step copper-chlorine cycle in hydrogen production and compression

Rapidly increasing global energy demands requires sustainable alternatives to conventional fossil fuels. Hydrogen emerges as a promising energy carrier due to its high energy density and minimal environmental impact, mainly when produced via thermochemical cycles like the Copper Chlorine (CuCl), which makes use of low-grade waste thermal energy for hydrogen production in an environmentally friendly manner. This study integrates hydrogen production using the Cu-Cl cycle and hydrogen compression systems crucial for establishing robust hydrogen infrastructure. Following hydrogen generation, the study examines the thermodynamic analysis of compressing hydrogen to higher pressures. Parametric variations in compression, including inlet and outlet pressures and the number of stages, are analyzed to optimize energy efficiency and exergy performance. Energy efficiency of around 47.05% is obtained for the 4-step Cu-Cl cycle. The integrated step showed a notably high exergy efficiency of 98.48%. Other key findings include a 35% increase in energy efficiency with five compression stages for an inlet pressure increment from 15 to 30 bars, and a 12% efficiency decrease when varying outlet pressure from 500 to 800 bars. Exergy efficiency shows a 17% improvement with increased compression stages under constant inlet pressure but a 4% decline when varying outlet pressure with a five-stage configuration. These findings highlight the critical role of efficient compression systems in enhancing hydrogen storage and distribution for sustainable energy applications.

Hydrogen supply chain for future hydrogen-fuelled railway in the UK: Transport sector focused

Though being attractive on railway decarbonisation for regional lines, excessive cost caused by immature hydrogen supply chain is one of the significant hurdles for promoting hydrogen traction to rolling stocks. Therefore, we conduct bespoke research on the UK's hydrogen supply chain for railway, concentrating on hydrogen transportation. Firstly, a map for the planned hydrogen production plants and potential hydrogen lines is developed with the location, capacity, and usage. A spatially explicit model for the hydrogen supply chain is then introduced, which optimises the existing grid-based methodology on accuracy and applicability. Compressed hydrogen at three pressures, and liquid hydrogen are considered as the mediums, incorporating by road and rail transport. Furthermore, three scenarios for hydrogen rail penetration are simulated respectively to discuss the levelised cost and the most suitable national transport network. The results show that the developed model with mix-integer linear programming (MILP) can well design the UK's hydrogen distribution for railway traction. Moreover, the hydrogen transport medium and vehicle should adjust to suit for different era where the penetration of hydrogen traction varies. The levelised cost of hydrogen (LCOH) decreases from 6.13 £/kg to 5.13 £/kg on average from the conservative scenario to the radical scenario. Applying different transport combinations according to the specific situation can satisfy the demand while reducing cost for multi-supplier and multi-targeting hydrogen transport.