Journal Description
Hydrogen
Hydrogen
is an international, peer-reviewed, open access journal on all aspects of hydrogen published quarterly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within ESCI (Web of Science), Scopus, CAPlus / SciFinder, and other databases.
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 15.4 days after submission; acceptance to publication is undertaken in 2.6 days (median values for papers published in this journal in the first half of 2024).
- Journal Rank: CiteScore - Q2 (Engineering (miscellaneous))
- Recognition of Reviewers: APC discount vouchers, optional signed peer review, and reviewer names published annually in the journal.
Latest Articles
Comparison of the Temperature, Radiation, and Heat Flux Distribution of a Hydrogen and a Methane Flame in a Crucible Furnace Using Numerical Simulation
Hydrogen 2024, 5(3), 459-473; https://doi.org/10.3390/hydrogen5030026 - 21 Jul 2024
Abstract
Sustainable technologies to replace current fossil solutions are essential to meet future CO2 emission reduction targets. Therefore, this paper compares key performance indicators of a hydrogen- and a methane-flame-fired crucible furnace with computational fluid dynamics simulations at identical firing powers, aiming to
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Sustainable technologies to replace current fossil solutions are essential to meet future CO2 emission reduction targets. Therefore, this paper compares key performance indicators of a hydrogen- and a methane-flame-fired crucible furnace with computational fluid dynamics simulations at identical firing powers, aiming to fully decarbonize the process. Validated numerical models from the literature were used to compare temperatures, radiation fields, radiation parameters and heat transfer characteristics. As a result, we observed higher combustion temperatures and a 19.0% higher fuel utilization rate in the hydrogen case, indicating more efficient operating modes, which could be related to the increased radiant heat flux and temperature ranges above 1750 K. Furthermore, higher scattering of the heat flux distribution on the crucible surface could be determined indicating more uneven melt bath temperatures. Further research could focus on quantifying the total fuel consumption required for the heating up of the furnace, for which a transient numerical model could be developed.
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(This article belongs to the Topic Hydrogen Energy Technologies, 2nd Volume)
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Open AccessArticle
Opportunities and Challenges of Hydrogen Ports: An Empirical Study in Australia and Japan
by
Peggy Shu-Ling Chen, Hongjun Fan, Hossein Enshaei, Wei Zhang, Wenming Shi, Nagi Abdussamie, Takashi Miwa, Zhuohua Qu and Zaili Yang
Hydrogen 2024, 5(3), 436-458; https://doi.org/10.3390/hydrogen5030025 - 11 Jul 2024
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This paper investigated the opportunities and challenges of integrating ports into hydrogen (H2) supply chains in the context of Australia and Japan because they are leading countries in the field and are potential leaders in the upcoming large-scale H2 trade.
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This paper investigated the opportunities and challenges of integrating ports into hydrogen (H2) supply chains in the context of Australia and Japan because they are leading countries in the field and are potential leaders in the upcoming large-scale H2 trade. Qualitative interviews were conducted in the two countries to identify opportunities for H2 ports, necessary infrastructure and facilities, key factors for operations, and challenges associated with the ports’ development, followed by an online survey investigating the readiness levels of H2 export and import ports. The findings reveal that there are significant opportunities for both countries’ H2 ports and their respective regions, which encompass business transition processes and decarbonisation. However, the ports face challenges in areas including infrastructure, training, standards, and social licence, and the sufficiency and readiness levels of port infrastructure and other critical factors are low. Recommendations were proposed to address the challenges and barriers encountered by H2 ports. To optimise logistics operations within H2 ports and facilitate effective integration of H2 applications, this paper developed a user-oriented working process framework to provide guidance to ports seeking to engage in the H2 economy. Its findings and recommendations contribute to filling the existing knowledge gap pertaining to H2 ports.
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Open AccessArticle
The Characteristics of a Ni/Cr/Ru Catalyst for a Biogas Dry Reforming Membrane Reactor Using a Pd/Cu Membrane and a Comparison of It with a Ni/Cr Catalyst
by
Akira Nishimura, Mizuki Ichikawa, Souta Yamada and Ryoma Ichii
Hydrogen 2024, 5(3), 414-435; https://doi.org/10.3390/hydrogen5030024 - 10 Jul 2024
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This study proposes a combination system consisting of a biogas dry reforming reactor and a solid oxide fuel cell (SOFC). Since biogas dry reforming is an endothermic reaction, this study adopted a membrane reactor operated due to the non-equilibrium state with H2
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This study proposes a combination system consisting of a biogas dry reforming reactor and a solid oxide fuel cell (SOFC). Since biogas dry reforming is an endothermic reaction, this study adopted a membrane reactor operated due to the non-equilibrium state with H2 separation from the reaction space. This study aimed to clarify the performance of the Ni/Cr/Ru catalyst using a biogas dry reforming membrane reactor. Additionally, this study also undertook a comparison of the performance of the Ni/Cr/Ru catalyst with that of the Ni/Cr catalyst. The impact of operation temperature, the molar ratio of CH4:CO2, the differential pressure between the reaction chamber and the sweep chamber, and the introduction of a sweep gas on the performance of the biogas dry reforming membrane reactor using a Pd/Cu membrane and a Ni/Cr/Ru catalyst was examined. The concentration of H2 using the Ni/Cr/Ru catalyst was greater than that using the Ni/Cr catalyst by 2871 ppmV for the molar ratio of CH4:CO2 = 1.5:1 at the reaction temperature of 600 °C and the differential pressure of 0 MPa without a sweep gas in particular. Under this condition, CH4 conversion, H2 yield, and thermal efficiency were 67.4%, 1.77 × 10−2%, and 0.241%, respectively.
Full article
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Open AccessArticle
PdS-ZnS-Doped Electrospun Polymer Nanofibers as Effective Photocatalyst for Hydrogen Evolution
by
Gopal Panthi and Arun Gyawali
Hydrogen 2024, 5(3), 403-413; https://doi.org/10.3390/hydrogen5030023 - 7 Jul 2024
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Poly(vinyl acetate) nanofibers doped with PdS-ZnS nanoparticles (PdS-ZnS/PVAc nanofibers) were fabricated via an electrospinning technique. PdS-ZnS nanoparticles were in situ synthesized by adding (NH4)2S solution to poly(vinyl acetate)/zinc acetate/palladium acetate solution. Electrospinning of the formed colloidal solution led to
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Poly(vinyl acetate) nanofibers doped with PdS-ZnS nanoparticles (PdS-ZnS/PVAc nanofibers) were fabricated via an electrospinning technique. PdS-ZnS nanoparticles were in situ synthesized by adding (NH4)2S solution to poly(vinyl acetate)/zinc acetate/palladium acetate solution. Electrospinning of the formed colloidal solution led to the formation of poly(vinyl acetate) nanofibers containing uniformly distributed PdS-ZnS nanoparticles. The prepared samples were characterized by field emission scanning electron microscopy, X-ray diffraction, transmission electron microscopy and Fourier transform infrared spectroscopy. In photocatalytic activity investigation, the PdS-ZnS/PVAc nanofibers showed remarkably enhanced performance towards water photosplitting under solar irradiation compared to the ZnS/PVAc nanofibers. This enhanced performance is attributed to the synergistic effects of heterostructured PdS-ZnS nanoparticles, which can improve photogenerated charge migration and solar light absorption.
Full article
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Open AccessCommunication
Instances of Safety-Related Advances in Hydrogen as Regards Its Gaseous Transport and Buffer Storage and Its Solid-State Storage
by
Farida Lamari, Benno Weinberger, Patrick Langlois and Daniel Fruchart
Hydrogen 2024, 5(3), 387-402; https://doi.org/10.3390/hydrogen5030022 - 4 Jul 2024
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As part of the ongoing transition from fossil fuels to renewable energies, advances are particularly expected in terms of safe and cost-effective solutions. Publicising instances of such advances and emphasising global safety considerations constitute the rationale for this communication. Knowing that high-strength steels
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As part of the ongoing transition from fossil fuels to renewable energies, advances are particularly expected in terms of safe and cost-effective solutions. Publicising instances of such advances and emphasising global safety considerations constitute the rationale for this communication. Knowing that high-strength steels can prove economically relevant in the foreseeable future for transporting hydrogen in pipelines by limiting the pipe wall thickness required to withstand high pressure, one advance relates to a bench designed to assess the safe transport or renewable-energy-related buffer storage of hydrogen gas. That bench has been implemented at the technology readiness level TRL 6 to test initially intact, damaged, or pre-notched 500 mm-long pipe sections with nominal diameters ranging from 300 to 900 mm in order to appropriately validate or question the use of reputedly satisfactory predictive models in terms of hydrogen embrittlement and potential corollary failure. The other advance discussed herein relates to the reactivation of a previously fruitful applied research into safe mass solid-state hydrogen storage by magnesium hydride through a new public–private partnership. This latest development comes at a time when markets have started driving the hydrogen economy, bearing in mind that phase-change materials make it possible to level out heat transfers during the absorption/melting and solidification/desorption cycles and to attain an overall energy efficiency of up to 80% for MgH2-based compacts doped with expanded natural graphite.
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Open AccessArticle
Local Environment and Migration Paths of the Proton Defect in Yttria-Stabilized Zirconia Studied by Ab Initio Calculations and Muon-Spin Spectroscopy
by
A. G. Marinopoulos, R. C. Vilão, H. V. Alberto, J. M. Gil, R. B. L. Vieira and J. S. Lord
Hydrogen 2024, 5(3), 374-386; https://doi.org/10.3390/hydrogen5030021 - 24 Jun 2024
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The local binding and migration behavior of the proton defect in cubic yttria-stabilized zirconia (YSZ) is studied by first-principles calculations and muon-spin spectroscopy (μSR) measurements. The calculations are based on density-functional theory (DFT) supplemented with a hybrid-functional approach with the proton
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The local binding and migration behavior of the proton defect in cubic yttria-stabilized zirconia (YSZ) is studied by first-principles calculations and muon-spin spectroscopy (μSR) measurements. The calculations are based on density-functional theory (DFT) supplemented with a hybrid-functional approach with the proton defect embedded in quasi-random supercells of 10.3 mol% yttria content, where the yttrium–zirconium substitutional defects are charge compensated by oxygen vacancies. Representative migration pathways for the proton comprising both transfer and bond reorientation modes are analysed and linked to the underlying microstructure of the YSZ lattice. The μSR data show the evolution of the diamagnetic fraction corresponding to the muon-isotope analogue with an activation energy of diffusion equal to 0.17 eV. Comparisons between the calculations and the experiment allow an assessment of the character of the short-range migration of the proton particle in cubic YSZ.
Full article
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Open AccessArticle
Environmental Impact Assessment of a 1 kW Proton-Exchange Membrane Fuel Cell: A Mid-Point and End-Point Analysis
by
Olubayo Moses Babatunde, Busola Dorcas Akintayo, Michael Uzoamaka Emezirinwune and Oludolapo Akanni Olanrewaju
Hydrogen 2024, 5(2), 352-373; https://doi.org/10.3390/hydrogen5020020 - 14 Jun 2024
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Proton-exchange membrane fuel cells (PEMFCs) are highly regarded as a promising technology for renewable energy generation; however, the environmental burden in their life cycle is a subject of concern. This study aimed to assess the environmental impact of producing a 1 kW PEMFC
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Proton-exchange membrane fuel cells (PEMFCs) are highly regarded as a promising technology for renewable energy generation; however, the environmental burden in their life cycle is a subject of concern. This study aimed to assess the environmental impact of producing a 1 kW PEMFC by a well-detailed cradle-to-gate evaluation, using mid-point and end-point impact assessment methods. The environmental impacts are related to the extraction of raw materials, consumption of energy, and transportation processes. Mid-point analysis shows that raw materials extraction and processing have a significant share in some impacts, including freshwater eutrophication, human carcinogenic toxicity, and terrestrial acidification. On the other hand, the energy consumed in fuel cell production plays a significant role in the impact categories of fossil resource depletion and global warming. The highest impact is attributed to the human health end-point analysis (0.000866 DALY), followed by the damage to ecosystems (1.04 × 10−6 species/yr) and resources (USD2013 6.16844). Normalization results further strengthen the importance of human health impacts and the necessity to solve problems regarding toxicity. The results of this work can provide directions toward enhancing the environmental sustainability of PEMFC technology and present a case for adopting a holistic approach to sustainability by looking across the life cycle of the technology.
Full article
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Open AccessArticle
Enhancing Hydrogen Recovery from Saline Aquifers: Quantifying Wettability and Hysteresis Influence and Minimizing Losses with a Cushion Gas
by
Rana Al Homoud, Marcos Vitor Barbosa Machado, Hugh Daigle, Kamy Sepehrnoori and Harun Ates
Hydrogen 2024, 5(2), 327-351; https://doi.org/10.3390/hydrogen5020019 - 13 Jun 2024
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This study aims to numerically assess the impact of wettability and relative permeability hysteresis on hydrogen losses during underground hydrogen storage (UHS) and explore strategies to minimize them by using an appropriate cushion gas. The research utilizes the Carlson model to calculate the
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This study aims to numerically assess the impact of wettability and relative permeability hysteresis on hydrogen losses during underground hydrogen storage (UHS) and explore strategies to minimize them by using an appropriate cushion gas. The research utilizes the Carlson model to calculate the saturation of trapped gas and the Killough model to account for water hysteresis. By incorporating the Land coefficient based on laboratory-measured data for a hydrogen/brine system, our findings demonstrate a significant influence of gas hysteresis on the hydrogen recovery factor when H2 is used as a cushion gas. The base model, which neglects the hysteresis effect, indicates a recovery factor of 78% by the fourth cycle, which can be improved. In contrast, the modified model, which considers hysteresis and results in a trapped gas saturation of approximately 17%, shows a hydrogen recovery factor of 45% by the fourth cycle. Additionally, gas hysteresis has a notable impact on water production, with an observed 12.5% increase in volume in the model that incorporates gas hysteresis. Furthermore, optimization of the recovery process was conducted by evaluating different cushion gases such as CO2, N2, and CH4, with the latter proving to be the optimal choice. These findings enhance the accuracy of estimating the H2 recovery factor, which is crucial for assessing the feasibility of storage projects.
Full article
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Open AccessReview
Artificial Intelligence-Driven Innovations in Hydrogen Safety
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Ravindra R. Patil, Rajnish Kaur Calay, Mohamad Y. Mustafa and Somil Thakur
Hydrogen 2024, 5(2), 312-326; https://doi.org/10.3390/hydrogen5020018 - 8 Jun 2024
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This review explores recent advancements in hydrogen gas (H2) safety through the lens of artificial intelligence (AI) techniques. As hydrogen gains prominence as a clean energy source, ensuring its safe handling becomes paramount. The paper critically evaluates the implementation of AI
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This review explores recent advancements in hydrogen gas (H2) safety through the lens of artificial intelligence (AI) techniques. As hydrogen gains prominence as a clean energy source, ensuring its safe handling becomes paramount. The paper critically evaluates the implementation of AI methodologies, including artificial neural networks (ANN), machine learning algorithms, computer vision (CV), and data fusion techniques, in enhancing hydrogen safety measures. By examining the integration of wireless sensor networks and AI for real-time monitoring and leveraging CV for interpreting visual indicators related to hydrogen leakage issues, this review highlights the transformative potential of AI in revolutionizing safety frameworks. Moreover, it addresses key challenges such as the scarcity of standardized datasets, the optimization of AI models for diverse environmental conditions, etc., while also identifying opportunities for further research and development. This review foresees faster response times, reduced false alarms, and overall improved safety for hydrogen-related applications. This paper serves as a valuable resource for researchers, engineers, and practitioners seeking to leverage state-of-the-art AI technologies for enhanced hydrogen safety systems.
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Open AccessArticle
Hydrogen Gas Compression for Efficient Storage: Balancing Energy and Increasing Density
by
Alessandro Franco and Caterina Giovannini
Hydrogen 2024, 5(2), 293-311; https://doi.org/10.3390/hydrogen5020017 - 25 May 2024
Abstract
This article analyzes the processes of compressing hydrogen in the gaseous state, an aspect considered important due to its contribution to the greater diffusion of hydrogen in both the civil and industrial sectors. This article begins by providing a concise overview and comparison
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This article analyzes the processes of compressing hydrogen in the gaseous state, an aspect considered important due to its contribution to the greater diffusion of hydrogen in both the civil and industrial sectors. This article begins by providing a concise overview and comparison of diverse hydrogen-storage methodologies, laying the groundwork with an in-depth analysis of hydrogen’s thermophysical properties. It scrutinizes plausible configurations for hydrogen compression, aiming to strike a delicate balance between energy consumption, derived from the fuel itself, and the requisite number of compression stages. Notably, to render hydrogen storage competitive in terms of volume, pressures of at least 350 bar are deemed essential, albeit at an energy cost amounting to approximately 10% of the fuel’s calorific value. Multi-stage compression emerges as a crucial strategy, not solely for energy efficiency, but also to curtail temperature rises, with an upper limit set at 200 °C. This nuanced approach is underlined by the exploration of compression levels commonly cited in the literature, particularly 350 bar and 700 bar. The study advocates for a three-stage compression system as a pragmatic compromise, capable of achieving high-pressure solutions while keeping compression work below 10 MJ/kg, a threshold indicative of sustainable energy utilization.
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(This article belongs to the Special Issue Recent Advances in Hydrogen Technologies: Production, Storage and Utilization)
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Open AccessArticle
Hydrogen Safety by Design: Exclusion of Flame Blow-Out from a TPRD
by
Mina Kazemi, Sile Brennan and Vladimir Molkov
Hydrogen 2024, 5(2), 280-292; https://doi.org/10.3390/hydrogen5020016 - 15 May 2024
Cited by 2
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Onboard hydrogen storage tanks are currently fitted with thermally activated pressure relief devices (TPRDs), enabling hydrogen to blowdown in the event of fire. For release diameters below the critical diameter, the flame from the TPRD may blow-out during a pressure drop. Flame blow-outs
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Onboard hydrogen storage tanks are currently fitted with thermally activated pressure relief devices (TPRDs), enabling hydrogen to blowdown in the event of fire. For release diameters below the critical diameter, the flame from the TPRD may blow-out during a pressure drop. Flame blow-outs pose a safety concern for an indoor or covered environment, e.g., a garage or carpark, where hydrogen can accumulate and deflagrate. This study describes the application of a validated computational fluid dynamics (CFD) model to simulate the dynamic flame behaviour from a TPRD designed to exclude its blow-out. The dynamic behaviour replicates a real scenario. Flame behaviour during tank blowdown through two TPRDs with different nozzle geometries is presented. Simulations confirm flame blow-out for a single-diameter TPRD of 0.5 mm during tank blowdown, while the double-diameter nozzle successfully excludes flame blow-out. The pressure at which the flame blow-out process is initiated during blowdown through a single-diameter nozzle was predicted.
Full article
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Open AccessReview
Unstable Metal Hydrides for Possible On-Board Hydrogen Storage
by
Zhijie Cao, Franziska Habermann, Konrad Burkmann, Michael Felderhoff and Florian Mertens
Hydrogen 2024, 5(2), 241-279; https://doi.org/10.3390/hydrogen5020015 - 10 May 2024
Cited by 1
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Hydrogen storage in general is an indispensable prerequisite for the introduction of a hydrogen energy-based infrastructure. In this respect, high-pressure metal hydride (MH) tank systems appear to be one of the most promising hydrogen storage techniques for automotive applications using proton exchange membrane
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Hydrogen storage in general is an indispensable prerequisite for the introduction of a hydrogen energy-based infrastructure. In this respect, high-pressure metal hydride (MH) tank systems appear to be one of the most promising hydrogen storage techniques for automotive applications using proton exchange membrane (PEM) fuel cells. These systems bear the potential of achieving a beneficial compromise concerning the comparably large volumetric storage density, wide working temperature range, comparably low liberation of heat, and increased safety. The debatable term “unstable metal hydride” is used in the literature in reference to metal hydrides with high dissociation pressure at a comparably low temperature. Such compounds may help to improve the merits of high-pressure MH tank systems. Consequently, in the last few years, some materials for possible on-board applications in such tank systems have been developed. This review summarizes the state-of-the-art developments of these metal hydrides, mainly including intermetallic compounds and complex hydrides, and offers some guidelines for future developments. Since typical laboratory hydrogen uptake measurements are limited to 200 bar, a possible threshold for defining unstable hydrides could be a value of their equilibrium pressure of peq > 200 bar for T < 100 °C. However, these values would mark a technological future target and most current materials, and those reported in this review, do not fulfill these requirements and need to be seen as current stages of development toward the intended target. For each of the aforementioned categories in this review, special care is taken to not only cover the pioneering and classic research but also to portray the current status and latest advances. For intermetallic compounds, key aspects focus on the influence of partial substitution on the absorption/desorption plateau pressure, hydrogen storage capacity and hysteresis properties. For complex hydrides, the preparation procedures, thermodynamics and theoretical calculation are presented. In addition, challenges, perspectives, and development tendencies in this field are also discussed.
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Open AccessArticle
Hydrogen Formation from Water with Various Reducing Metals Catalyzed by In Situ-Generated Nickel Nanoparticles
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Ron Shirman and Yoel Sasson
Hydrogen 2024, 5(2), 230-240; https://doi.org/10.3390/hydrogen5020014 - 3 May 2024
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Water is a potential green source for the generation of clean elemental hydrogen without contaminants. One of the most convenient methods for hydrogen generation is based on the oxidation of different metals by water. The inspection of the catalytic activity toward hydrogen formation
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Water is a potential green source for the generation of clean elemental hydrogen without contaminants. One of the most convenient methods for hydrogen generation is based on the oxidation of different metals by water. The inspection of the catalytic activity toward hydrogen formation from water performed in this study was carried out using four different metals, namely, zinc, magnesium, iron, and manganese. The process is catalyzed by in situ-generated nickel nanoparticles. The zinc–water system was found to be the most effective and exhibited 94% conversion in 4 h. The solid phase in the latter system was characterized by PXRD and SEM techniques. Several blank tests provided a fundamental understanding of the role of each constituent within the system, and a molecular mechanism for the catalytic cycle was proposed.
Full article
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Graphical abstract
Open AccessArticle
The Case of Renewable Methane by and with Green Hydrogen as the Storage and Transport Medium for Intermittent Wind and Solar PV Energy
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John G. Ingersoll
Hydrogen 2024, 5(2), 209-229; https://doi.org/10.3390/hydrogen5020013 - 2 May 2024
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Long-duration energy storage is the key challenge facing renewable energy transition in the future of well over 50% and up to 75% of primary energy supply with intermittent solar and wind electricity, while up to 25% would come from biomass, which requires traditional
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Long-duration energy storage is the key challenge facing renewable energy transition in the future of well over 50% and up to 75% of primary energy supply with intermittent solar and wind electricity, while up to 25% would come from biomass, which requires traditional type storage. To this end, chemical energy storage at grid scale in the form of fuel appears to be the ideal option for wind and solar power. Renewable hydrogen is a much-considered fuel along with ammonia. However, these fuels are not only difficult to transport over long distances, but they would also require totally new and prohibitively expensive infrastructure. On the other hand, the existing natural gas pipeline infrastructure in developed economies can not only transmit a mixture of methane with up to 20% hydrogen without modification, but it also has more than adequate long-duration storage capacity. This is confirmed by analyzing the energy economies of the USA and Germany, both possessing well-developed natural gas transmission and storage systems. It is envisioned that renewable methane will be produced via well-established biological and/or chemical processes reacting green hydrogen with carbon dioxide, the latter to be separated ideally from biogas generated via the biological conversion of biomass to biomethane. At the point of utilization of the methane to generate power and a variety of chemicals, the released carbon dioxide would be also sequestered. An essentially net zero carbon energy system would be then become operational. The current conversion efficiency of power to hydrogen/methane to power on the order of 40% would limit the penetration of wind and solar power. Conversion efficiencies of over 75% can be attained with the on-going commercialization of solid oxide electrolysis and fuel cells for up to 75% penetration of intermittent renewable power. The proposed hydrogen/methane system would then be widely adopted because it is practical, affordable, and sustainable.
Full article
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Open AccessArticle
HyPLANT100: Industrialization from Assembly to the Construction Site for Gigawatt Electrolysis
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Lukas Büsch, Malte Jakschik, Daniel Syniawa, Christian Masuhr, Lukas Christ, Jan Schachtsiek, Kay Haalck, Leon Nerlich, Elisabeth Frömsdorf, Nadine Schirmack, Benedikt Ebert, Chaman Kirty, Patrick Adler, Thorsten Schüppstuhl and Bernd Kuhlenkötter
Hydrogen 2024, 5(2), 185-208; https://doi.org/10.3390/hydrogen5020012 - 28 Apr 2024
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The global push for sustainable energy has heightened the demand for green hydrogen, which is crucial for decarbonizing heavy industry. However, current electrolysis plant capacities are insufficient. This research addresses the challenge through optimizing large-scale electrolysis construction via standardization, modularization, process optimization, and
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The global push for sustainable energy has heightened the demand for green hydrogen, which is crucial for decarbonizing heavy industry. However, current electrolysis plant capacities are insufficient. This research addresses the challenge through optimizing large-scale electrolysis construction via standardization, modularization, process optimization, and automation. This paper introduces H2Giga, a project for mass-producing electrolyzers, and HyPLANT100, investigating large-scale electrolysis plant structure and construction processes. Modularizing electrolyzers enhances production efficiency and scalability. The integration of AutomationML facilitates seamless information exchange. A digital twin concept enables simulations, optimizations, and error identification before assembly. While construction site automation provides advantages, tasks like connection technologies and handling cables, tubes, and hoses require pre-assembly. This study identifies key tasks suitable for automation and estimating required components. The Enapter Multicore electrolyzer serves as a case study, showcasing robotic technology for tube fittings. In conclusion, this research underscores the significance of standardization, modularization, and automation in boosting the electrolysis production capacity for green hydrogen, contributing to ongoing efforts in decarbonizing the industrial sector and advancing the global energy transition.
Full article
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Open AccessReview
A Review of Alternative Processes for Green Hydrogen Production Focused on Generating Hydrogen from Biomass
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Aikaterina Paraskevi Damiri, Emmanuel Stamatakis, Spyros Bellas, Manos Zoulias, Georgios Mitkidis, Anestis G. Anastasiadis, Sotiris Karellas, George Tzamalis, Athanasios Stubos and Theocharis Tsoutsos
Hydrogen 2024, 5(2), 163-184; https://doi.org/10.3390/hydrogen5020011 - 28 Apr 2024
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Hydrogen plays a leading role in achieving a future with net zero greenhouse gas emissions. The present challenge is producing green hydrogen to cover the fuel demands of transportation and industry to gain independence from fossil fuels. This review’s goal is to critically
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Hydrogen plays a leading role in achieving a future with net zero greenhouse gas emissions. The present challenge is producing green hydrogen to cover the fuel demands of transportation and industry to gain independence from fossil fuels. This review’s goal is to critically demonstrate the existing methods of biomass treatment and assess their ability to scale up. Biomass is an excellent hydrogen carrier and biomass-derived processes are the main target for hydrogen production as they provide an innovative pathway to green hydrogen production. Comparing the existing processes, thermochemical treatment is found to be far more evolved than biological or electrochemical treatment, especially with regard to scaling prospects.
Full article
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Open AccessArticle
On the Scalability of a Membrane Unit for Ultrapure Hydrogen Separation
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Vincenzo Narcisi, Luca Farina and Alessia Santucci
Hydrogen 2024, 5(2), 149-162; https://doi.org/10.3390/hydrogen5020010 - 17 Apr 2024
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Hydrogen permeation sparked a renewed interest in the second half of the 20th century due to the favorable features of this element as an energy factor. Furthermore, niche applications such as nuclear fusion gained attention for the highest selectivity ensured by self-supported dense
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Hydrogen permeation sparked a renewed interest in the second half of the 20th century due to the favorable features of this element as an energy factor. Furthermore, niche applications such as nuclear fusion gained attention for the highest selectivity ensured by self-supported dense metallic membranes, especially those consisting of Pd-based alloys. In this framework, the ENEA Frascati laboratories have decades of experience in the manufacturing, integration, and operation of Pd-Ag permeators. Most of the experimental investigations were performed on single-tube membranes, proving their performance under relevant operational conditions. Nowadays, once the applicability of this technology has been demonstrated, the scalability of the single-tube experience over medium- and large-scale units must be verified. To do this, ENEA Frascati laboratories have designed and constructed a multi-tube permeator, namely the Medium-Scaled Membrane Reactor (MeSMeR), focused on scalability assessment. In this work, the results obtained with the MeSMeR facility have been compared with previous experimental campaigns conducted on single-tube units, and the scalability of the permeation results has been proven. Moreover, post-test simulations have been performed based on single-tube finite element modeling, proving the scalability of the numerical outcomes and the possibility of using this tool for scale-up design procedures.
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Effect of Metal Carbides on Hydrogen Embrittlement: A Density Functional Theory Study
by
Omar Faye and Jerzy A. Szpunar
Hydrogen 2024, 5(1), 137-148; https://doi.org/10.3390/hydrogen5010009 - 20 Mar 2024
Abstract
This study uses plane wave density functional theory (DFT) to investigate the effect of certain metal carbides (Niobium carbide, Vanadium carbide, Titanium carbide, and Manganese sulfide) on hydrogen embrittlement in pipeline steels. Our results predict that the interaction of hydrogen molecules with these
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This study uses plane wave density functional theory (DFT) to investigate the effect of certain metal carbides (Niobium carbide, Vanadium carbide, Titanium carbide, and Manganese sulfide) on hydrogen embrittlement in pipeline steels. Our results predict that the interaction of hydrogen molecules with these metal carbides occurs in the long range with binding energy varying in the energy window [0.043 eV to 0.70 eV].In addition, our study shows the desorption of H2 molecules from these metal carbides in the chemisorptions. Since atomic state hydrogen interacts with NbC, VC, TiC, and MnS to cause embrittlement, we classified the strength of the hydrogen trapping as TiC + H > VC + H > NbC + H> MnS + H. In addition, our study reveals that the carbon site is a more favorable hydrogen-trapping site than the metal one.
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(This article belongs to the Special Issue Feature Papers in Hydrogen (Volume 2))
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Open AccessArticle
Effect of Cr/Mn Addition in TiVNb on Hydrogen Sorption Properties: Thermodynamics and Phase Transition Study
by
Anis Bouzidi, Erik Elkaim, Vivian Nassif and Claudia Zlotea
Hydrogen 2024, 5(1), 123-136; https://doi.org/10.3390/hydrogen5010008 - 18 Feb 2024
Cited by 1
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High-entropy alloys (HEAs) are a promising class of materials that can grant remarkable functional performances for a large range of applications due to their highly tunable composition. Among these applications, recently, bcc HEAs capable of forming fcc hydrides have been proposed as high-capacity
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High-entropy alloys (HEAs) are a promising class of materials that can grant remarkable functional performances for a large range of applications due to their highly tunable composition. Among these applications, recently, bcc HEAs capable of forming fcc hydrides have been proposed as high-capacity hydrogen storage materials with improved thermodynamics compared to classical metal hydrides. In this context, a single-phase bcc (TiVNb)0.90Cr0.05Mn0.05 HEA was prepared by arc melting to evaluate the effect of combined Cr/Mn addition in the ternary TiVNb. A thermodynamic destabilization of the fcc hydride phase was found in the HEA compared to the initial TiVNb. In situ neutron and synchrotron X-ray diffraction experiments put forward a fcc → bcc phase transition of the metallic subnetwork in the temperature range of 260–350 °C, whereas the H/D subnetwork underwent an order → disorder transition at 180 °C. The absorption/desorption cycling demonstrated very fast absorption kinetics at room temperature in less than 1 min with a remarkable total capacity (2.8 wt.%) without phase segregation. Therefore, the design strategy consisting of small additions of non-hydride-forming elements into refractory HEAs allows for materials with promising properties for solid-state hydrogen storage to be obtained.
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Open AccessArticle
An Exploration of Safety Measures in Hydrogen Refueling Stations: Delving into Hydrogen Equipment and Technical Performance
by
Matteo Genovese, David Blekhman and Petronilla Fragiacomo
Hydrogen 2024, 5(1), 102-122; https://doi.org/10.3390/hydrogen5010007 - 17 Feb 2024
Cited by 4
Abstract
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The present paper offers a thorough examination of the safety measures enforced at hydrogen filling stations, emphasizing their crucial significance in the wider endeavor to advocate for hydrogen as a sustainable and reliable substitute for conventional fuels. The analysis reveals a wide range
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The present paper offers a thorough examination of the safety measures enforced at hydrogen filling stations, emphasizing their crucial significance in the wider endeavor to advocate for hydrogen as a sustainable and reliable substitute for conventional fuels. The analysis reveals a wide range of crucial safety aspects in hydrogen refueling stations, including regulated hydrogen dispensing, leak detection, accurate hydrogen flow measurement, emergency shutdown systems, fire-suppression mechanisms, hydrogen distribution and pressure management, and appropriate hydrogen storage and cooling for secure refueling operations. The paper therefore explores several aspects, including the sophisticated architecture of hydrogen dispensers, reliable leak-detection systems, emergency shut-off mechanisms, and the implementation of fire-suppression tactics. Furthermore, it emphasizes that the safety and effectiveness of hydrogen filling stations are closely connected to the accuracy in the creation and upkeep of hydrogen dispensers. It highlights the need for materials and systems that can endure severe circumstances of elevated pressure and temperature while maintaining safety. The use of sophisticated leak-detection technology is crucial for rapidly detecting and reducing possible threats, therefore improving the overall safety of these facilities. Moreover, the research elucidates the complexities of emergency shut-off systems and fire-suppression tactics. These components are crucial not just for promptly managing hazards, but also for maintaining the station’s structural soundness in unanticipated circumstances. In addition, the study provides observations about recent technical progress in the industry. These advances effectively tackle current safety obstacles and provide the foundation for future breakthroughs in hydrogen fueling infrastructure. The integration of cutting-edge technology and materials, together with the development of upgraded safety measures, suggests a positive trajectory towards improved efficiency, dependability, and safety in hydrogen refueling stations.
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