Hydrogen

21 pages, 14214 KiB

Open AccessArticle

Polarization and Forward Scattering Effects in Low Energy Positron Collisions with H₂

by Wagner Tenfen, Josiney de Souza Glória, Sarah Esther da Silva Saab, Eliton Popovicz Seidel and Felipe Arretche

Hydrogen 2025, 6(1), 2; https://doi.org/10.3390/hydrogen6010002 - 10 Jan 2025

Abstract

Positron physical-chemistry has been one important focus of scientific investigation of the last decades, however their low energy scattering by atoms and molecules still offers many questions to be answered, as the low angle scattering effects on the measured cross sections and how [...] Read more.

Positron physical-chemistry has been one important focus of scientific investigation of the last decades, however their low energy scattering by atoms and molecules still offers many questions to be answered, as the low angle scattering effects on the measured cross sections and how the degree of target polarization manifest in the comparison between theoretical and experimental results. In this work, we investigate low energy positron collisions by H₂ molecules, with particular attention to the convergence of the polarization contribution on the scattering potential. The interaction between positron and molecule was represented by a model potential conceived from the composition of a free electron gas correlation term with an asymptotic polarization potential, obtained from perturbation theory. In particular, we investigated how polarization effects beyond the second order perturbation affect the scattering observables. Our results show that the model which includes up to the quadrupole polarization contribution presents better agreement to the recent experimental data when corrected for forward scattering effects, since they were measured from a transmission beam technique. The angular distributions were also examined through the comparison between our results to the folded differential cross sections measurements available in the literature. We propose a simple correction scheme to the experimental folded differential cross sections for energies below 1 eV which then, as we argue, favorably compares to the quadrupole polarization model. Finally, the comparison between our phase shifts and scattering lengths with recent full many body ab initio results that explicitly include virtual positronium effects suggests that these are intrisically included in the adopted model correlation potential. Full article

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18 pages, 6069 KiB

Open AccessArticle

Techno-Economic Feasibility of Fuel Cell Vehicle-to-Grid Fast Frequency Control in Non-Interconnected Islands

by Tziotas Christos, Evangelos E. Pompodakis and Georgios I. Orfanoudakis

Hydrogen 2025, 6(1), 1; https://doi.org/10.3390/hydrogen6010001 - 24 Dec 2024

Abstract

This paper presents an innovative approach to fast frequency control in electric grids by leveraging parked fuel cell electric vehicles (FCEVs), especially heavy-duty vehicles such as trucks. Equipped with hydrogen storage tanks and fuel cells, these vehicles can be repurposed as dynamic grid-support [...] Read more.

This paper presents an innovative approach to fast frequency control in electric grids by leveraging parked fuel cell electric vehicles (FCEVs), especially heavy-duty vehicles such as trucks. Equipped with hydrogen storage tanks and fuel cells, these vehicles can be repurposed as dynamic grid-support assets while parked in designated areas. Using an external cable and inverter system, FCEVs inject power into the grid by converting DC from fuel cells into AC, to be compatible with grid requirements. This functionality addresses sudden power imbalances, providing a rapid and efficient solution for frequency stabilization. The system’s external inverter serves as a central control hub, monitoring real-time grid frequency and directing FCEVs to supply virtual inertia and primary reserves through droop control, as required. Simulation results validate that FCEVs could effectively complement thermal generators, preventing unacceptable frequency drops, load shedding, and network blackouts. A techno-economic analysis demonstrates the economic feasibility of the concept, concluding that each FCEV consumes approximately 0.3 kg of hydrogen per day, incurring a daily cost of around EUR 1.5. For an island grid with a nominal power of 100 MW, maintaining frequency stability requires a fleet of 100 FCEVs, resulting in a total daily cost of EUR 150. Compared to a grid-scale battery system offering equivalent frequency response services, the proposed solution is up to three times more cost-effective, highlighting its economic and technical potential for grid stabilization in renewable-rich, non-interconnected power systems. Full article

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16 pages, 1885 KiB

Open AccessArticle

Green Hydrogen Blending into the Tunisian Natural Gas Distributing System

by Hadhami Bdioui, Hazem Touati, Maher Ben Chiekh and Angeles López-Agüera

Hydrogen 2024, 5(4), 1004-1019; https://doi.org/10.3390/hydrogen5040054 - 17 Dec 2024

Abstract

It is likely that blending hydrogen into natural gas grids could contribute to economy-wide decarbonization while retaining some of the benefits that natural gas networks offer energy systems. Hydrogen injection into existing natural gas infrastructure is recognised as a key solution for energy [...] Read more.

It is likely that blending hydrogen into natural gas grids could contribute to economy-wide decarbonization while retaining some of the benefits that natural gas networks offer energy systems. Hydrogen injection into existing natural gas infrastructure is recognised as a key solution for energy storage during periods of low electricity demand or high variable renewable energy penetration. In this scenario, natural gas networks provide an energy vector parallel to the electricity grid, offering additional energy transmission capacity and inherent storage capabilities. By incorporating green hydrogen into the NG network, it becomes feasible to (i) address the current energy crisis, (ii) reduce the carbon intensity of the gas grid, and (iii) promote sector coupling through the utilisation of various renewable energy sources. This study gives an overview of various interchangeability indicators and investigates the permissible ratios for hydrogen blending with two types of natural gas distributed in Tunisia (ANG and MNG). Additionally, it examines the impact of hydrogen injection on energy content variation and various combustion parameters. It is confirmed by the data that ANG and MNG can withstand a maximum hydrogen blend of up to 20%. The article’s conclusion emphasises the significance of evaluating infrastructure and safety standards related to Tunisia’s natural gas network and suggests more experimental testing of the findings. This research marks a critical step towards unlocking the potential of green hydrogen in Tunisia. Full article

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17 pages, 2669 KiB

Open AccessArticle

High Efficiency in Clean Hydrogen Production Using Water and AlLi Phases Prepared by Mechanical Alloying

by José Luis Iturbe-García and Diana Laura Alvarez-Acosta

Hydrogen 2024, 5(4), 987-1003; https://doi.org/10.3390/hydrogen5040053 - 9 Dec 2024

Abstract

In this work, the results of clean hydrogen production from the direct chemical reaction between aluminum–lithium compounds and distilled water under normal conditions, without additives or catalysts, are presented. The material was prepared by mechanical alloying using a high-energy Spex-type mill in an [...] Read more.

In this work, the results of clean hydrogen production from the direct chemical reaction between aluminum–lithium compounds and distilled water under normal conditions, without additives or catalysts, are presented. The material was prepared by mechanical alloying using a high-energy Spex-type mill in an Al20Li ratio. Relatively short milling times were programmed for the preparation of AlLi phases. Through this process, two phases (AlLi and Al8.9Li1.1) were identified, which react efficiently to produce clean hydrogen. The experiments demonstrate fast and self-sustained reactions between AlLi phases and distilled water. In both the phase preparation and hydrogen generation, 100% efficiency was achieved. The hydrolysis reaction occurred quickly, and the hydrogen volume generated was 1700 mL/g of material. Under these conditions, aluminum generates 1390 mL of hydrogen, and lithium generates 310 mL/g from both AlLi phases. A single by-product (LiAl₂(OH)₇·2H₂O) was identified. According to the results and the conditions applied in this research, the hydrogen produced does not require prior purification and can therefore be used directly in fuel cells. The AlLi–water reaction is a promising process for generating hydrogen in a simple and relatively short time compared to other hydrogen production methods. In this process, no greenhouse gas emissions were produced. Full article

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11 pages, 3718 KiB

Open AccessCommunication

Simulation and Quantitative Assessment of Sensor Placement in a Hydrogen Bus for Risk Mitigation

by Xintao Deng, Jinwei Sun, Fuyuan Yang and Minggao Ouyang

Hydrogen 2024, 5(4), 976-986; https://doi.org/10.3390/hydrogen5040052 - 8 Dec 2024

Abstract

The cleanliness of hydrogen energy throughout its life cycle has enabled its applications in transportation and buildings. However, such scenarios often involve the storage and use of hydrogen in enclosed spaces. Ensuring the facility’s safety during hydrogen accidental leakage through rapid detection and [...] Read more.

The cleanliness of hydrogen energy throughout its life cycle has enabled its applications in transportation and buildings. However, such scenarios often involve the storage and use of hydrogen in enclosed spaces. Ensuring the facility’s safety during hydrogen accidental leakage through rapid detection and emergency measures has been a long-standing topic. In this work, we analyze hydrogen leakage in a hydrogen bus through CFD simulation. By extracting the hydrogen diffusion time and combining it with the leakage frequency and ignition probability, we quantitatively evaluate the placement of the sensors and propose an index for detection system assessment named the average detection delay index (ADDI). A near-field detection sensor was introduced to the system, which reduced the lower ADDI limit of the detection system by up to 10 times while reducing the system cost without changing the level of performance. Full article

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18 pages, 3223 KiB

Open AccessArticle

Sustainable Production of Green Oxy-Hydrogen from Vehicles’ Air Conditioning Drains to Enhance Engine Efficiency and Reduce Greenhouse Gas Emissions

by Mohamed K. M. Gerwash, Amin M. K. Al-ghonemy, Mohamed A. Omara, Ibrahim L. M. Ahmed, Aly Saeed and Gamal B. Abdelaziz

Hydrogen 2024, 5(4), 958-975; https://doi.org/10.3390/hydrogen5040051 - 5 Dec 2024

Abstract

Innovative and sustainable solutions are increasingly necessary as concerns about fossil fuels’ environmental and economic impacts grow. Accordingly, this study aims to enhance vehicle internal combustion engine efficiency by producing oxy-hydrogen (HHO) from drain water from the vehicle air conditioning system and utilizing [...] Read more.

Innovative and sustainable solutions are increasingly necessary as concerns about fossil fuels’ environmental and economic impacts grow. Accordingly, this study aims to enhance vehicle internal combustion engine efficiency by producing oxy-hydrogen (HHO) from drain water from the vehicle air conditioning system and utilizing it as a secondary fuel. A 1600 cc Daewoo engine equipped with electronic fuel injection was employed as the test subject. Initially, the engine’s performance was evaluated using various gasoline variants, 80, 92, and 95. The 92-octane gasoline demonstrated the highest efficiency, achieving a peak power of 113 kW and torque of 190 Nm. The engine had an 11:1 compression ratio. Then, different flow rates of oxy-hydrogen, 50, 248, 397, and 480 mL/min, generated from the air conditioner drain were combined with 92 fuel. A significant improvement was observed with the increase in the flow rate of oxy-hydrogen gas to the 92 fuel. The results indicated that incorporating 480 mL/min oxy-hydrogen gas into the fuel led to an 8.7% reduction in fuel consumption, 5.5% enhancement in thermal efficiency, and 7.9% in volumetric efficiency. Greenhouse gas emissions reductions of carbon monoxide, carbon dioxide, and hydrocarbons were recorded as 18%, 9.2%, and 9%, respectively. At the same time, nitrogen oxides increased by 12.5%. Therefore, utilizing a vehicle air conditioner drain water to generate oxy-hydrogen gas fuel in conjunction with 92-octane gasoline is an efficient solution to reduce fuel consumption, enhance energy efficiency, and mitigate the adverse effects of pollution. This approach also contributes to progress towards a more sustainable future. Full article

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18 pages, 3972 KiB

Open AccessArticle

Enhanced Photocatalytic Hydrogen Evolution by TiO₂: A Synergistic Approach with Defect-Rich SnS₂ and Ti₃C₂ MXene Cocatalysts

by Saminathan Varadarajan, Andiappan Kavitha, Periasamy Selvaraju, Sankaran Esakki Muthu, Krishnamoorthy Gurushankar, Sengottaiyan Shanmugan and Karthik Kannan

Hydrogen 2024, 5(4), 940-957; https://doi.org/10.3390/hydrogen5040050 - 4 Dec 2024

Abstract

Enhanced photo-induced electron utilization leads to efficient photocatalytic hydrogen production. The inefficient separation of photo-induced electron–hole pairs has hindered this process. This study introduces a synergistic approach using defect-rich SnS₂ and Ti₃C₂ MXene as cocatalysts in a two-step hydrothermal [...] Read more.

Enhanced photo-induced electron utilization leads to efficient photocatalytic hydrogen production. The inefficient separation of photo-induced electron–hole pairs has hindered this process. This study introduces a synergistic approach using defect-rich SnS₂ and Ti₃C₂ MXene as cocatalysts in a two-step hydrothermal process to address this challenge. By integrating these materials with TiO₂ nanosheets, we create a novel composite, SnS₂/Ti₃C₂/TiO₂ (STT), that significantly boosts photocatalytic hydrogen evolution. The defect-rich SnS₂ provides abundant active sites for hydrogen generation, while Ti₃C₂ MXene facilitates photo-induced charge separation. The synergistic combination of charge carrier diffusion enhances chromophore absorption, thereby increasing the overall photocatalytic hydrogen-production rate, achieving several grams of hydrogen per hour per gram of double cocatalysts with molybdenum vacancies. Characterization techniques confirm the phase composition of the composite (STT). Compared to pristine TiO₂ and other composites, the STT composite, optimized with a 150 °C hydrothermal treatment, shows a photocatalytic H₂-production rate nearly 192 times higher than that of pure TiO₂ and 6 times higher than that of other composites. The presence of molybdenum vacancies in SnS₂ further enhances its specific activity for hydrogen evolution by suppressing carrier recombination and providing additional active sites. Moreover, Ti₃C₂ MXene and SnS₂ act as dual cocatalysts, improving electronic conductivity and electron-transfer efficiency. Our findings demonstrate the potential of combining defect-rich SnS₂ and Ti₃C₂ MXene to develop highly efficient and sustainable photocatalysts for hydrogen production. TiO₂ has been in situ grown on highly conductive Ti₃C₂ MXene, and SnS₂, rich in molybdenum vacancies, is uniformly distributed on the TiO₂/Ti₃C₂ composite through the two-step hydrothermal method. The presence of molybdenum vacancies in SnS₂ further enhances its specific activity for hydrogen evolution by suppressing carrier recombination and providing additional active sites. Moreover, Ti₃C₂ MXene and SnS₂ act as dual cocatalysts, improving electronic conductivity and electron-transfer efficiency. Our findings demonstrate the potential of combining defect-rich SnS₂ and Ti₃C₂ MXene to develop highly efficient and sustainable photocatalysts for hydrogen production. Full article

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11 pages, 3867 KiB

Open AccessArticle

Influence of Nb Content on Structure and Functional Properties of Novel Multicomponent Nb–Ni–Ti–Zr–Co Alloy for Hydrogen Separation Membrane Application

by Egor B. Kashkarov, Leonid A. Svyatkin, Kirill S. Gusev, Sergey S. Ognev, Maksim Koptsev, Daria V. Terenteva, Tatyana L. Murashkina and Andrey M. Lider

Hydrogen 2024, 5(4), 929-939; https://doi.org/10.3390/hydrogen5040049 - 21 Nov 2024

Abstract

Novel multicomponent Nb–Ni–Ti–Zr–Co alloys with 20–55 at.% Nb were synthesized from metal powders by arc melting. The resulting alloys consist primarily of Nb-rich and eutectic body-centered (BCC) phases. The content of the eutectic BCC phase is highest for an equimolar composition, while the [...] Read more.

Novel multicomponent Nb–Ni–Ti–Zr–Co alloys with 20–55 at.% Nb were synthesized from metal powders by arc melting. The resulting alloys consist primarily of Nb-rich and eutectic body-centered (BCC) phases. The content of the eutectic BCC phase is highest for an equimolar composition, while the content of the Nb-rich BCC phase increases with Nb content in the alloy. The content of secondary phases is the highest for the alloy with 32 at.% Nb. According to ab initio calculations, hydrogen occupies tetrahedral interstitial sites in the Nb-rich phase and octahedral sites in the eutectic BCC phase. For different Nb concentrations, hydrogen-binding energies were calculated. An increase in the Nb-rich phase leads to softening of multicomponent alloys. The alloys with 20 and 32 at.% Nb demonstrate high hydrogen permeability (1.05 and 0.96 × 10⁻⁸ molH₂m⁻¹s⁻¹Pa^−0.5, respectively) at 400 °C, making them promising for hydrogen purification membrane application. Multicomponent alloys with a high Nb content (55 at.%) have low resistance to hydrogen embrittlement. Full article

(This article belongs to the Special Issue Recent Advances in Hydrogen Technologies: Production, Storage and Utilization)

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10 pages, 2163 KiB

Open AccessArticle

Hydrogen-Rich Syngas Production Based on a Co-Gasification Process Coupled to a Water–Gas Shift Reactor Without Steam Injection

by Eliseu Monteiro, Ouissal Bourguig and Abel Rouboa

Hydrogen 2024, 5(4), 919-928; https://doi.org/10.3390/hydrogen5040048 - 20 Nov 2024

Abstract

Future decarbonized applications that rely on renewable and carbon-dioxide-neutral hydrogen production could benefit from the gasification of waste to produce hydrogen. In the current study, an Aspen Plus^® model was developed by coupling a co-gasification model to a water–gas shift (WGS) model. [...] Read more.

Future decarbonized applications that rely on renewable and carbon-dioxide-neutral hydrogen production could benefit from the gasification of waste to produce hydrogen. In the current study, an Aspen Plus^® model was developed by coupling a co-gasification model to a water–gas shift (WGS) model. The feedstock employed in the simulations was a blend of municipal solid waste (MSW) and biomass from Morocco. A parametric assessment was conducted to analyze the effect of the steam-to-feedstock ratio (SFR) on the syngas composition and the WGS reactor temperature. This study also presents a comparison between the results of the gasification process before and after the WGS reactor, using air and steam as the gasifying agent. The results show an increase in hydrogen volumetric percentage for higher steam-to-feedstock ratios in the gasifier. Moreover, the inclusion of a WGS reactor enhances hydrogen and carbon dioxide while reducing the amount of carbon monoxide in the syngas for both air and steam as the gasifying agents. It can be concluded that a co-gasification process can be intensified by coupling it to a WGS reactor without steam injection to produce hydrogen-rich syngas with reduced operational expenditures. Full article

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18 pages, 3152 KiB

Open AccessReview

Explosions of Hydrogen Storages and the Safety Considerations in Hydrogen-Powered Railway Applications—A Review

by Yan-Quan Sun

Hydrogen 2024, 5(4), 901-918; https://doi.org/10.3390/hydrogen5040047 - 19 Nov 2024

Abstract

As one of the most promising clean energy sources, hydrogen power has gradually emerged as a viable alternative to traditional energy sources. However, hydrogen safety remains a significant concern due to the potential for explosions and the associated risks. This review systematically examines [...] Read more.

As one of the most promising clean energy sources, hydrogen power has gradually emerged as a viable alternative to traditional energy sources. However, hydrogen safety remains a significant concern due to the potential for explosions and the associated risks. This review systematically examines hydrogen explosions, with a focus on high-pressure and low-temperature storage, transportation, and usage processes mostly based on the published papers from 2020. The fundamental principles of hydrogen explosions, classifications, and analysis methods, including experimental testing and numerical simulations, are explored. Key factors influencing hydrogen explosions are also discussed. The safety issues of hydrogen power on railway applications are focused, and finally, recommendations are provided for the safe application of hydrogen power in railway transportation, particularly for long-distance travel and heavy-duty freight trains, with an emphasis on storage safety considerations. Full article

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19 pages, 3954 KiB

Open AccessArticle

Mechanistic Study and Active Sites Investigation of Hydrogen Production from Methane and H₂O Steady-State and Transient Reactivity with Ir/GDC Catalyst

by Farah Lachquer and Jamil Toyir

Hydrogen 2024, 5(4), 882-900; https://doi.org/10.3390/hydrogen5040046 - 17 Nov 2024

Abstract

Catalytic activity, mechanisms, and active sites were determined for methane steam reforming (MSR) over gadolinium-doped ceria (GDC) supported iridium (0.1 wt%) prepared by impregnation of GDC with iridium acetylacetonate. Isothermal steady-state rate measurements followed by micro-gas chromatography analysis were performed at 660 and [...] Read more.

Catalytic activity, mechanisms, and active sites were determined for methane steam reforming (MSR) over gadolinium-doped ceria (GDC) supported iridium (0.1 wt%) prepared by impregnation of GDC with iridium acetylacetonate. Isothermal steady-state rate measurements followed by micro-gas chromatography analysis were performed at 660 and 760 °C over Ir/GDC samples pretreated in N₂ or H₂ at 900 °C. Transient responses to CH₄ or H₂O step changes in isothermal conditions were carried out at 750 °C over Ir/GDC pretreated in He or H₂ using online quadrupole mass spectrometry. In the proposed mechanism, Ir/GDC proceeds through a dual-type active site associating, as follows: (i) Ir metallic particles surface as active sites for the cracking of CH₄ into reactive C species, and (ii) reducible (Ce⁴⁺) sites at GDC surface responsible for a redox mechanism involving Ce⁴⁺/Ce³⁺ sites, being reduced by reaction with reactive C into CO (or CO₂) depending on the oxidation state of GDC and re-oxidized by H₂O. Full reduction of reducible oxygen species is possible with CH₄ after He treatment, whereas only 80% is reached in CH₄ after H₂ treatment. Full article

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10 pages, 3337 KiB

Open AccessArticle

Novel Sulfamethoxazole Organotin Complexes: Synthesis, Characterization, and Hydrogen Storage Application

by Dina S. Ahmed, Noor Emad, Mohammed Kadhom, Emad Yousif and Mohammed Al-Mashhadani

Hydrogen 2024, 5(4), 872-881; https://doi.org/10.3390/hydrogen5040045 - 13 Nov 2024

Abstract

This study presents the synthesis and characterization of novel sulfamethoxazole organotin complexes and evaluates their potential for hydrogen storage applications. The synthesized complexes were characterized using various techniques, such as Nuclear Magnetic Resonance and Fourier Transform Infrared spectroscopy to determine their constructional and [...] Read more.

This study presents the synthesis and characterization of novel sulfamethoxazole organotin complexes and evaluates their potential for hydrogen storage applications. The synthesized complexes were characterized using various techniques, such as Nuclear Magnetic Resonance and Fourier Transform Infrared spectroscopy to determine their constructional and physicochemical properties. Field Emission Scanning Electron Microscopy was applied to analyze the surface morphology, and the Brunauer–Emmett–Teller method was utilized to measure the surface area. High-pressure adsorption experiments demonstrated the remarkable hydrogen storage capabilities of these complexes, with the highest hydrogen uptake of 29.1 cm³/g observed at 323 K. The results suggest that the prepared sulfamethoxazole organotin complexes have the potential to be candidates for gas separation and storage applications. Full article

(This article belongs to the Special Issue Advancements in Hydrogen Storage Materials and DFT-Based Studies)

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21 pages, 2303 KiB

Open AccessArticle

Development of a Method for Evaluating H2-Filling Stations

by Bastian Nolte, Dominik Gollnick, Armin Stein and Thomas Vietor

Hydrogen 2024, 5(4), 851-871; https://doi.org/10.3390/hydrogen5040044 - 12 Nov 2024

Abstract

To expedite the development of the infrastructural expansion for hydrogen applications, the research project “THEWA” was founded. Within this project, the development of hydrogen-refueling stations is being advanced so that the hydrogen strategy for mobility in Germany can move forward. One development point [...] Read more.

To expedite the development of the infrastructural expansion for hydrogen applications, the research project “THEWA” was founded. Within this project, the development of hydrogen-refueling stations is being advanced so that the hydrogen strategy for mobility in Germany can move forward. One development point of the project is to develop an evaluation model that recommends a concept for hydrogen-refueling stations for initial individual situations. In this work, an evaluation method is developed that provides an appropriate recommendation. For this purpose, basics, such as the general structure of hydrogen-refueling stations, their classification into functional areas, and already-existing evaluation methods for multi-criteria decisions, are shown. The method for the evaluation of hydrogen-refueling stations will be developed in a component-based manner, for which a selection of influencing factors of hydrogen-refueling stations will be explained and categorized. With the help of an expert workshop, these are scaled so that the result is an evaluation method based on an expert assessment and the consideration of individual customer requirements. In addition, the method is implemented in a tool so that it can be used more easily. Full article

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32 pages, 6809 KiB

Open AccessArticle

Integrating Deep Learning and Energy Management Standards for Enhanced Solar–Hydrogen Systems: A Study Using MobileNetV2, InceptionV3, and ISO 50001:2018

by Salaki Reynaldo Joshua, Yang Junghyun, Sanguk Park and Kihyeon Kwon

Hydrogen 2024, 5(4), 819-850; https://doi.org/10.3390/hydrogen5040043 - 10 Nov 2024

Cited by 1

Abstract

This study addresses the growing need for effective energy management solutions in university settings, with particular emphasis on solar–hydrogen systems. The study’s purpose is to explore the integration of deep learning models, specifically MobileNetV2 and InceptionV3, in enhancing fault detection capabilities in AIoT-based [...] Read more.

This study addresses the growing need for effective energy management solutions in university settings, with particular emphasis on solar–hydrogen systems. The study’s purpose is to explore the integration of deep learning models, specifically MobileNetV2 and InceptionV3, in enhancing fault detection capabilities in AIoT-based environments, while also customizing ISO 50001:2018 standards to align with the unique energy management needs of academic institutions. Our research employs comparative analysis of the two deep learning models in terms of their performance in detecting solar panel defects and assessing accuracy, loss values, and computational efficiency. The findings reveal that MobileNetV2 achieves 80% accuracy, making it suitable for resource-constrained environments, while InceptionV3 demonstrates superior accuracy of 90% but requires more computational resources. The study concludes that both models offer distinct advantages based on application scenarios, emphasizing the importance of balancing accuracy and efficiency when selecting appropriate models for solar–hydrogen system management. This research highlights the critical role of continuous improvement and leadership commitment in the successful implementation of energy management standards in universities. Full article

(This article belongs to the Special Issue Recent Advances in Hydrogen Technologies: Production, Storage and Utilization)

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19 pages, 5410 KiB

Open AccessArticle

Modeling of Dry Reforming of Methane Using Artificial Neural Networks

by Mohammod Hafizur Rahman and Mohammad Biswas

Hydrogen 2024, 5(4), 800-818; https://doi.org/10.3390/hydrogen5040042 - 7 Nov 2024

Abstract

The process of dry reforming methane (DRM) is seen as a viable approach for producing hydrogen and lowering the atmospheric concentration of carbon dioxide. Recent times have witnessed notable advancements in the development of catalysts that enable this pathway. Numerous experiments have been [...] Read more.

The process of dry reforming methane (DRM) is seen as a viable approach for producing hydrogen and lowering the atmospheric concentration of carbon dioxide. Recent times have witnessed notable advancements in the development of catalysts that enable this pathway. Numerous experiments have been conducted to investigate the use of nickel-based catalysts in the dry reforming of methane. All these reported experiments showed that variations in the catalyst property, namely pore size, pore volume, and surface area, affect the hydrogen production in DRM. None of the previous studies has modeled the surface nickel-incorporated catalyst activity based on its properties. In this research, DRM’s hydrogen yield is predicted using three different artificial neural network-learning algorithms as a function of the physical properties of Ni-based catalyst along with two reaction inputs. The geometric properties as an input set are a different approach to developing such empirical models. The best-fitting models are the artificial neural network model using the Levenberg–Marquardt algorithm and ten hidden neurons, which gave a coefficient of determination of 0.9931 and an MSE of 7.51, and the artificial neural network model using the scaled conjugate gradient algorithm and eight hidden layer neurons, which had a coefficient of determination of 0.9951 and an MSE of 4.29. This study offers useful knowledge on how to improve the DRM processes. Full article

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24 pages, 4549 KiB

Open AccessReview

Tuning the Morphology of Transition Metal Disulfides: Advances in Electrocatalysts for Hydrogen Evolution Reaction

by Shravani S. Jakkanawar, Vijay D. Chavan, Deok-Kee Kim, Tejasvinee S. Bhat and Hemraj M. Yadav

Hydrogen 2024, 5(4), 776-799; https://doi.org/10.3390/hydrogen5040041 - 2 Nov 2024

Abstract

The hydrogen evolution reaction (HER) in the renewable energy system has gained a lot of attention from researchers as hydrogen is assumed to be a clean and renewable carrier. Transition metals and their compounds have been used as promising alternatives to precious noble [...] Read more.

The hydrogen evolution reaction (HER) in the renewable energy system has gained a lot of attention from researchers as hydrogen is assumed to be a clean and renewable carrier. Transition metals and their compounds have been used as promising alternatives to precious noble metals for the HER, offering low cost, more availability, and high activity. In this work, we discussed the mechanisms of the HER and how morphology influenced the catalytic performance of transition metal disulfide (TMD), focusing on structures that range from zero-dimensional (0D) to three-dimensional (3D) TMD materials. Notably, two-dimensional (2D) TMDs, like nanosheets, exhibit the lowest overpotential and a very small Tafel slope, which can be ascribed to their inherent layered structure and large surface area. According to recent research reports, the efficacy and efficiency of the HER process are influenced by surface chemistry, electrochemical characteristics, and the existence of active sites. Full article

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15 pages, 1156 KiB

Open AccessArticle

Comparative Hydrogen Production Routes via Steam Methane Reforming and Chemical Looping Reforming of Natural Gas as Feedstock

by Salmi Mohd Yunus, Suzana Yusup, Siti Sorfina Johari, Nurfanizan Mohd Afandi, Abreeza Manap and Hassan Mohamed

Hydrogen 2024, 5(4), 761-775; https://doi.org/10.3390/hydrogen5040040 - 21 Oct 2024

Cited by 1

Abstract

Hydrogen production is essential in the transition to sustainable energy. This study examines two hydrogen production routes, steam methane reforming (SMR) and chemical looping reforming (CLR), both using raw natural gas as feedstock. SMR, the most commonly used industrial process, involves reacting methane [...] Read more.

Hydrogen production is essential in the transition to sustainable energy. This study examines two hydrogen production routes, steam methane reforming (SMR) and chemical looping reforming (CLR), both using raw natural gas as feedstock. SMR, the most commonly used industrial process, involves reacting methane with steam to produce hydrogen, carbon monoxide, and carbon dioxide. In contrast, CLR uses a metal oxide as an oxygen carrier to facilitate hydrogen production without generating additional carbon dioxide. Simulations conducted using Aspen HYSYS analyzed each method’s performance and energy consumption. The results show that SMR achieved 99.98% hydrogen purity, whereas CLR produced 99.97% purity. An energy analysis revealed that CLR requires 31% less energy than SMR, likely due to the absence of low- and high-temperature water–gas shift units. Overall, the findings suggest that CLR offers substantial advantages over SMR, including lower energy consumption and the production of cleaner hydrogen, free from carbon dioxide generated during the water–gas shift process. Full article

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24 pages, 13398 KiB

Open AccessArticle

Integration of Wind Energy and Geological Hydrogen Storage in the Bakken Formation, North Dakota: Assessing the Potential of Depleted Reservoirs for Hydrogen Storage

by Shree Om Bade, Emmanuel Gyimah, Rachael Josephs, Toluwase Omojiba, Rockson Aluah and Olusegun Stanley Tomomewo

Hydrogen 2024, 5(4), 737-760; https://doi.org/10.3390/hydrogen5040039 - 17 Oct 2024

Abstract

Geological hydrogen storage, seen as a viable solution for addressing energy demands and mitigating the intermittency of wind power, is gaining recognition. At present, there are no specific studies that estimate hydrogen storage capacity and the potential for wind integration in North Dakota [...] Read more.

Geological hydrogen storage, seen as a viable solution for addressing energy demands and mitigating the intermittency of wind power, is gaining recognition. At present, there are no specific studies that estimate hydrogen storage capacity and the potential for wind integration in North Dakota despite the state’s enormous energy resources and capabilities. The study’s key innovation lies in repurposing a region historically associated with oil and gas for sustainable energy storage, thereby addressing the intermittency of wind sources. Moreover, the innovative aspect of this study involves field selection, site screening, characterization, and mathematical modeling to simulate a wind–hydrogen production and geological storage system. A 15 MW wind farm, using real-world data from General Electric wind turbines, is employed to assess storage capacities within the Middle Bakken formation. The study reveals substantial storage potentials in wells W24814, W19693, and W26990, with capacities of 54,000, 33,000, and 22,000 tons, respectively. These capacities translate to energy storage capabilities of 1080, 660, and 440 GWh, with minimum storage durations of 140, 80, and 57 days, respectively, under a 60% system efficiency. By pioneering the integration of wind energy with geological hydrogen storage in a region traditionally dominated by fossil fuel extraction, this research could play a crucial role in advancing North Dakota’s energy transition, providing a blueprint for similar initiatives globally. Full article

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14 pages, 2184 KiB

Open AccessArticle

A Technical Study on an Integrated Closed-Loop Solid Oxide Fuel Cell and Ammonia Decomposition System for Marine Application

by Shengwei Wu, Bin Miao and Siew Hwa Chan

Hydrogen 2024, 5(4), 723-736; https://doi.org/10.3390/hydrogen5040038 - 13 Oct 2024

Abstract

The International Maritime Organization (IMO) sets ambitious greenhouse gas reduction targets for the maritime industry. From a long-term net zero emission perspective, ammonia fuel is expected to play a significant role in the marine decarbonization journey compared to LNG as a transition fuel. [...] Read more.

The International Maritime Organization (IMO) sets ambitious greenhouse gas reduction targets for the maritime industry. From a long-term net zero emission perspective, ammonia fuel is expected to play a significant role in the marine decarbonization journey compared to LNG as a transition fuel. Also, in addition to internal combustion engine applications, solid oxide fuel cells (SOFCs) have gained more attention in marine propulsion applications due to their high efficiency. This study was performed to investigate the technical feasibility of utilizing a closed-loop SOFC thermal energy release for ammonia decomposition, leading to hydrogen fuel generation and subsequently feed back into SOFCs. The result proves that the integrated system of ammonia cracking SOFCs can maintain a self-balanced condition, ensuring adequate SOFC heat supply for the ammonia cracking process to produce hydrogen while supporting normal SOFC operation and generating heat. This paper concludes that an integrated system represents a novel and feasible solution and emphasizes its potential as an adaptable solution for future marine applications. Full article

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