Institution of Gas Engineers & Managers

Water photoelectrolysis cells based on photoelectrochemical water splitting seem to be an interesting alternative to other traditional green hydrogen generation processes (e.g. water electrolysis). Unfortunately the practical application of this technology is currently hindered by several difficulties: low solar-to-hydrogen (STH) efficiency expensive electrode materials etc. A novel concept based on a tandem photoelectrolysis cell configuration with an anion-conducting membrane separating the photoanode from the photocathode has already been proposed in the literature. This approach allows the use of low-cost metal oxide electrodes and nickel-based co-catalysts. In this paper we conducted a study to evaluate the economic and environmental sustainability of this technology using the environmental life cycle cost. Preliminary results have revealed two main interesting aspects: the negligible percentage of externalities in the total cost.

To address the collaborative optimization challenge in multi-microgrid systems with significant renewable energy integration this study presents a dual-layer optimization model incorporating power-hydrogen coupling. Firstly a hydrogen energy system coupling framework including photovoltaics storage batteries and electrolysis hydrogen production/fuel cells was constructed at the architecture level to realize the flexible conversion of multiple energy forms. From a modeling perspective the upper-layer optimization aims to minimize lifecycle costs by determining the optimal sizing of distributed PV systems battery storage hydrogen tanks fuel cells and electrolyzers within the microgrid. At the lower level a distributed optimization framework facilitates energy sharing (both electrical and hydrogen-based) across microgrids. This operational layer maximizes yearly system revenue while considering all energy transactions—both inter-microgrid and grid-to-microgrid exchanges. The resulting operational boundaries feed into the upper-layer capacity optimization with the optimal equipment configuration emerging from the iterative convergence of both layers. Finally the actual microgrid in a certain area is taken as an example to verify the effectiveness of the proposed method.

Hydrogen production from gasification of biowaste generates large volumes of CO2 due to endothermic biowaste decomposition. Alternatively the Sun can provide that energy. To evaluate the yield and performance of solarbased gasifiers at country scale a multi-scale approach is required. First the operation of a solar gasifier is analyzed by developing a two-phase model validated and scaled to industrial level. Next the performance and yield of such technology as a function of the radiation received is studied taking Spain as a case study. The results were promising obtaining a syngas rich in H2. However tar and char were not reduced due to insufficient temperature. Scale-up studies revealed energy losses to the environment in the industrial-scale gasifier which suggested the use of segmented heating. In turn diameters no larger than 0.8 m and biomass feeding rates below 0.85 kg/s highlight the deployment of a modular design due to particle size limitations. Finally the large-scale waste valorization showed that the gasifier can only operate in Spain in the summer months. It can run over 180 h/month and more than 250 days/year only in C´ adiz and Santa Cruz de Tenerife which also showed the highest yearly production capacities.

Water management is crucial for the performance of anion exchange membrane water electrolyzers (AEM-WEs) to maintain membrane hydration and enable phase separation between hydrogen gas and liquid water. Therefore careful material selection for the anode and cathode is essential to enhance reactant/product transport and optimize water management under ‘dry cathode’ conditions. This study investigates the wetting characteristics of two commercially available porous transport layers (PTLs) used in AEM-WE: carbon paper and carbon paper with a microporous layer (MPL). Wettability was measured under static quasi-static and dynamic conditions to assess the effect of water and electrolytes (NaOH KOH K2CO3) across concentrations (up to 1 M) and operational temperatures (20 °C to 92 °C). Carbon paper exhibits mild hydrophobicity (advancing contact angles of ∼120° however with receding contact angle ∼0°) whereas carbon paper with MPL demonstrates superhydrophobicity (advancing and receding contact angles >145° and low contact angle hysteresis) maintaining a stable Cassie-Baxter wetting state. Dynamic wetting experiments confirmed the robustness of the superhydrophobicity in carbon paper with MPL facilitating phase separation between hydrogen gas and liquid water. The presence of supporting electrolytes did not significantly affect wettability and the materials retained hydrophobic properties across different temperatures. These findings highlight the importance of MPLs in optimizing water transport and gas rejection within AEM-WEs ensuring efficient and stable operation under “dry cathode” conditions. These PTLs (with and without the addition of the MPL) were integrated into AEM-WE and polarization curves were run. Preliminary data in a specific condition suggested the presence of the MPL within the PTL enhance AEM-WE performance.

Within energy system analysis there is discourse regarding the role and economic benefits of nuclear energy in terms of overall system costs. The reported findings range from considerable drawbacks to substantial benefits depending on the chosen models scenarios and underlying assumptions. This article addresses existing gaps by demonstrating how subtle variations in model assumptions significantly impact analysis outcomes. Historically uncertainties associated with nuclear energy costs have been well documented whereas renewable energy costs have steadily declined and have been relatively predictable. However as land availability increasingly constrains future renewable expansion development is shifting from onshore to offshore locations where cost uncertainties are greater and anticipated cost reductions are less reliable. This study emphasizes this fundamental shift highlighting how uncertainties in future renewable energy costs could strengthen the economic case of nuclear energy within fully integrated sector-coupled energy systems especially when the costs of all technologies and weather conditions are set in the moderate range. Focusing specifically on Denmark this article presents a thorough sensitivity analysis of renewable energy costs and weather conditions within anticipated future ranges providing a nuanced perspective on the role of nuclear energy. Ultimately the findings underscore that when examining total annual system costs the differences between scenarios with low and high nuclear energy shares are minimal and are within ±5 % for the baseline assumptions while updated adjustments reduce this variation to ±1 %.

Hydrogen production from water electrolysis can not only reduce greenhouse gas emissions but also has abundant raw materials which is one of the ideal ways to produce hydrogen from new energy. The hydrogen production power supply is the core component of the new energy electrolytic water hydrogen production device and its characteristics have a significant impact on the efficiency and purity of hydrogen production and the service life of the electrolytic cell. In essence the DC/DC converter provides the large current required for hydrogen production. For the converter its input still needs the support of a DC power supply. Given the maturity and technical characteristics of new energy power generation integrating energy storage into offshore energy systems enables stable power supply. This configuration not only mitigates energy fluctuations from renewable sources but also further reduces electrolysis costs providing a feasible pathway for large-scale commercialization of green hydrogen production. First this paper performs a simulation analysis on the wind–solar hybrid energy storage power generation system to demonstrate that the wind–solar–storage system can provide stable power support. It places particular emphasis on the significance of hydrogen production power supply design—this focus stems primarily from the fact that electrolyzers impose specific requirements on high operating current levels and low current ripple which exert a direct impact on the electrolyzer’s service life hydrogen production efficiency and operational safety. To suppress the current ripple induced by high switching frequency and high output current traditional approaches typically involve increasing the output inductor. However this method substantially increases the volume and weight of the device reduces the rate of current change and ultimately results in a degradation of the system’s dynamic response performance. To this end this paper focuses on developing a virtual impedance control technology aiming to reduce the ripple amplitude while avoiding an increase in the filter inductor. Owing to constraints in current experimental conditions this research temporarily relies on simulation data. Specifically a programmable power supply is employed to simulate the voltage output of the wind–solar–storage hybrid system thereby bringing the simulation as close as possible to the actual operating conditions of the wind–solar–storage hydrogen production system. The experimental results demonstrate that the proposed method can effectively suppress the ripple amplitude maintain high operating efficiency and ultimately meet the expected research objectives. That makes it particularly suitable as a high-quality power supply for offshore hydrogen production systems that have strict requirements on volume and weight.

Achieving net-zero emissions requires major changes across a nation’s economy energy and land systems particularly due to sectors where emissions are difficult to eliminate. Here we adapt two global scenarios from the International Energy Agency—the net-zero emissions by 2050 and the Stated Policies Scenario—using an integrated numerical economic-energy model tailored to Australia. We explore how emissions may evolve by sector and identify key technologies for decarbonisation. Our results show that a rapid shift to near-zero emissions electricity is central to reducing costs and enabling wider emissions reductions. From 2030 onwards carbon removal through land management and engineered solutions such as direct air capture and bioenergy with carbon capture and storage becomes critical. Australia is also well-positioned to become a global supplier of clean energy such as hydrogen made using renewable electricity helping reduce emissions beyond its borders.

This study explores a multi-faceted approach to improving the combustion performance and emission characteristics of a single-cylinder four-stroke direct injection (DI) compression ignition engine through the combined effects of butanol enrichment green-synthesized copper oxide (CuO) nanoparticles and hydrogen supplementation. The baseline fuel was a B20 biodiesel blend further enriched with 10 % butanol to enhance oxygen availability and atomization. CuO nanoparticles were synthesized via an eco-friendly aloe vera extractmediated method and dispersed into the fuel to promote oxidation kinetics and stabilize combustion. Experimental results revealed that the B20+But10 %+CuO100 blend achieved the highest brake thermal efficiency (BTE) of 33.6 % at full load alongside notable reductions in carbon monoxide (CO) unburned hydrocarbons (HC) nitrogen oxides (NOx) and smoke opacity compared to neat B20. Reactivity controlled compression ignition (RCCI) trials further demonstrated that hydrogen enrichment at 5 LPM and 10 LPM improved flame propagation Brake thermal efficiency (33.89 % & 35.43 %) and reduced brake-specific fuel consumption of nearly 10 % (0.26 Kg/KWh) & 0.25 Kg/KWh). While excessive hydrogen supply (10 LPM) marginally increased HC emissions (110 PPM) at higher loads due to localized incomplete oxidation overall results confirm significant emission mitigation. The findings highlight that the synergistic integration of butanol oxygenation catalytically active CuO nanoparticles and optimized hydrogen enrichment offers a viable pathway toward cleaner combustion improved energy efficiency and reduced pollutant emissions in biodiesel-fueled CI engines.

Ammonia represents a promising alternative fuel and hydrogen carrier for power generation due to its advantages in storage and transportation compared to those of hydrogen. However challenges persist in the direct use of ammonia in solid oxide fuel cells (SOFCs) particularly with respect to performance degradation—an issue that necessitates comprehensive investigation at the full-stack scale. This study examines a ten-cell full-size SOFC stack under various operating conditions to evaluate the viability of ammonia as a direct fuel. Experiments were conducted using pure ammonia pure hydrogen fully reformed ammonia and 50 % pre-reformed ammonia at three operating temperatures (660◦C 710 ◦C and 760 ◦C). Performance was characterized through current–voltage curves electrochemical impedance spectroscopy and continuous monitoring of residual ammonia in the exhaust using Fourier-transform infrared spectroscopy. A 200-hour durability test was performed to assess long-term stability. The results demonstrated that at temperatures of ≥ 710 ◦C ammonia-fueled SOFCs performed comparably to hydrogen-fueled configurations within typical operating ranges (0.2–0.5 A/cm2 ). The stack achieved optimal performance at 55–80 % fuel utilization. The ammonia-fueled configurations exhibited different voltage behaviors at higher fuel utilizations compared with those of the hydrogen-fueled configurations. The residual ammonia concentration in the anode off-gas remained well below the safety thresholds. Long-term testing demonstrated an initial degradation that eventually stabilized at a more sustainable rate. These findings validate ammonia as a viable fuel for SOFC stacks when operated at appropriate temperatures (≥710 ◦C) and optimal fuel utilization offering a pathway toward sustainable carbon-free ammonia energy systems.

This study develops and applies a life cycle assessment (LCA) framework combined with predictive market models to evaluate the environmental impacts of electricity and hydrogen for transport in the EU27+UK from 2020 to 2050. By linking evolving power sector scenarios with hydrogen supply models we assess the wellto-wheels (WTW) performance of battery electric vehicles (BEVs) and fuel cell electric vehicles (FCEVs) under consistent energy assumptions. Results show that electricity decarbonization can reduce GWP by up to 80% by 2050 but increases land use and mineral/metal demand due to renewable infrastructure expansion. The environmental impacts of hydrogen production are strongly influenced by the electricity mix especially in high electrolysis scenarios. WTW analysis indicates that while BEVs consistently achieve lower WTW GWP than FCEVs across all scenarios both drivetrains exhibit notable trade-offs in other impact categories. Scenarios dominated by blue hydrogen although not optimal in terms of GWP present a more balanced environmental profile making them a viable transitional pathway in contexts that prioritize minimizing other environmental impacts.

The thermal management system and the balance-of-plant (BoP) in fuel cell electric vehicles (FCEV) are characterized by a particularly high level of complexity and a number of interfaces. Optimizing the efficiency of the overall vehicle is of special importance to maximize the range and increase the attractiveness of this technology to customers. This paper focuses on the optimization potential of the air supply system in the BoP whereby the charging concepts of the electric supercharger (ESC) and the electrically assisted turbocharger (EAT) as well as the integration of water spray injection (WSI) at the compressor inlet are investigated in the framework of an FCEV complete vehicle co-simulation. As a benchmark for the integration of these optimization measures the complete vehicle co-simulation is designed for a fuel cell electric passenger car of the current generation. Here thermo-hydraulic fluid circuits in the thermal management software KULI are coupled with mathematical-physical models in MATLAB/Simulink. Applying advanced simulation methodologies for the components of fuel cell powertrain and vehicle cabin enables the mapping of the effects of realistic operating conditions on the FCEV characteristics. The EAT offers the advantage over the ESC that due to the arrangement of an exhaust gas turbine a part of the exhaust gas enthalpy flow downstream of the fuel cell stack can be recovered which reduces the electrical compressor drive power. Moreover an additional reduction of this power consumption can be achieved by WSI as the effect of evaporative cooling lowers the initial compression temperature. For analysis and comparison these concepts are again modeled with high degree of detail and integrated into the benchmark overall vehicle simulation. The results indicate considerable reductions in the electric compressor drive power of the EAT compared to the ESC with noteworthy potential for reducing the vehicle’s hydrogen consumption. At an operating point in Worldwide harmonized Light Duty Test Cycle (WLTC) under 35 ◦ C ambient temperature and 25 % relative humidity the electrical compressor drive power shows a reduction potential of −40 % which corresponds to a vehicle-level hydrogen consumption reduction of up to −3 %. In addition the results also highlight the effect of the WSI in both charging concepts whereby its potential to reduce the hydrogen consumption on the overall vehicle level is relatively small. In WLTC at 35 ◦C ambient temperature and 25 % relative humidity the compressor drive power reduction potential for ESC and EAT averages −5 % while the effect on hydrogen consumption is only around −0.25 %.

Clean hydrogen (H2) is highly desirable for the sustainable development of society in the era of carbon neutrality. However the current capability of water electrolysis and steam methane (CH4) reforming to produce green and blue H2 is very limited mainly due to the high production cost difficult scale-up technology or operational risk. Here we propose the direct catalytic decomposition of diesel using a nano-Fe-based catalyst to produce the so-called ‘‘jadeite H2” while simultaneously fixing the carbon from the diesel in the form of carbon nanotubes (CNTs). Efforts are made to understand the suppression mechanism of the CH4 byproduct such as by tuning the catalyst type space velocity and reaction time. The optimal green index (GI)—that is the molar ratio of H2/carbon in a gaseous state—of the proposed technology exceeds 42 which is far higher than those of any previously reported chemical vapor deposition (CVD) method. Moreover the carbon footprint (CFP) of the proposed technology is far lower than those of grey H2 blue H2 and other dehydrogenation technologies. Compared with most of the technologies mentioned above the energy consumption (per mole of H2) and reactor amplification of the proposed technology validate its high efficiency and great practical feasibility.

As the global push for carbon neutrality accelerates energy efficiency has become essential for sustainable development especially for nations like Nigeria that face rising energy demands and significant environmental challenges. This study explores how integrating energy efficiency with carbon neutrality can support Nigeria’s strategic energy goals while offering global lessons for other countries facing similar challenges focusing on key sectors including industry transport and power generation. The study systematically examines the impacts of renewable energy (RE) technologies like solar wind and hydropower—alongside policy reforms technological innovations and demand-side management strategies to advance energy efficiency in Nigeria. Key findings include the identification of strategic policy frameworks technological solutions and the transformative role of green hydrogen in decarbonizing hard-to-electrify sectors. The study also emphasizes the importance of international climate finance decentralized RE systems like solar mini-grids for improving energy access and economic opportunities for job creation in the RE sector. Furthermore it highlights the need for behavioral changes community engagement and consistent policy implementation to address infrastructure gaps and drive energy efficiency goals. The novelty of this research lies in its scenario-based analysis of Nigeria’s low-carbon transition detailing both the opportunities and challenges such as policy inconsistencies infrastructure deficits and financial constraints. The findings stress the importance of international collaboration technological advancements and targeted investments to overcome these challenges. By offering actionable insights and strategic recommendations this study provides a roadmap for policymakers industry stakeholders and researchers to drive Nigeria towards a sustainable carbon-neutral future by 2050.

This paper presents QDQN-ThermoNet a novel Quantum-Driven Dual Deep Q-Network framework for intelligent thermal regulation in next-generation electric vehicles with hybrid energy systems. Our approach introduces a dual-agent architecture where a classical DQN governs solid-state battery thermal management while a quantumenhanced DQN regulates proton exchange membrane fuel cell dynamics both sharing a unified quantumenhanced experience replay buffer to facilitate cross-system information transfer. Hardware-in-the-Loop validation across diverse operational scenarios demonstrates significant performance improvements compared to classical methods including enhanced thermal stability (95.1 % vs. 82.3 %) faster thermal response (2.1 s vs. 4.7 s) reduced overheating events (0.3 vs. 3.2) and superior energy efficiency (22.4 % energy savings). The quantum-enhanced components deliver 38.7 % greater sample efficiency and maintain robust performance under sparse data conditions (33.9 % improvement) while material-adaptive control strategies leveraging MXeneenhanced phase change materials achieve a 50.3 % reduction in peak temperature rise during transients. Component lifetime analysis reveals a 33.2 % extension in battery service life through optimized thermal management. These results establish QDQN-ThermoNet as a significant advancement in AI-driven thermal management for future electric vehicle platforms effectively addressing the complex challenges of coordinating thermal regulation across divergent energy sources with different optimal operating temperatures.

In response to the growing global interest in hydrogen as an energy carrier this study provides the first attempt to develop a baseline inventory of U.S. hydrogen emissions from production distribution and storage. The scope of this study was limited to pure hydrogen emissions and excludes emissions from low purity hydrogen streams and carriers. A detailed literature search was conducted utilizing various greenhouse gas emissions inventory protocol principles and guidelines to consolidate a list of activity data and emission factors. The best available activity data and emission factors were then selected via a Multi-Criteria-Based Decision Making Method named Technique for Order Preference by Similarity to Ideal Solution or modelled using best-engineering estimates. The study estimated total U.S. hydrogen emissions of 0.063 MMTA with emission bounds ranging from 0.02 to 0.11 MMTA. Given the total estimated H2 production capacity of 7.97 MMTA the study estimates a total U.S. hydrogen emission rate for production distribution and storage of 0.79% (0.26%–1.32%). To reduce the uncertainty in the estimated total hydrogen emissions future work should be conducted to measure facility-level hydrogen emission factors across multiple sectors. The inventory framework developed in this study can serve as a living document that can be updated and enhanced as more empirical data is obtained. This study also provides detailed insights regarding key emission or leakage sources and causes from each supply chain stage. The insights and conclusions from this study can provide direction for hydrogen production companies and safety professionals as they develop hydrogen emission mitigation measures and controls.

This study investigates numerically combustion attributes and NOx formation of premixed ammonia-hydrogen/air flames within a swirl burner of a gas turbine considering various conditions of hydrogen fraction (HF: 0 % 5 % 30 % 40 % and 50 %) equivalence ratio (φ: 0.85 1.0 and 1.2) and mixture inlet temperature (Tin: 400–600 K). The results illustrate that flame temperature increases with hydrogen addition from 1958 K for pure ammonia to 2253 K at 50 % HF. Raising the inlet temperature from 400 K to 600 K markedly enhances combustion intensity resulting in an increase of the Damköhler number (Da) from 117 to 287. NOx levels rise from ∼1800 ppm (0 % HF) to ∼7500 ppm (50 % HF) and peak at 8243 ppm under lean conditions (φ = 0.85). Individual NO N2O and NO2 emissions also reach maxima at φ = 0.85 with values of 5870 ppm 2364 ppm and 10 ppm respectively decreasing significantly under richer conditions (2547 ppm 1245 ppm and 5 ppm at φ = 1.2). These results contribute to advancing low-carbon fuel technologies and highlight the viability of ammonia-hydrogen co-firing as a pathway toward sustainable gas turbine operation.

The development of large-scale flexible and safe hydrogen storage is critical for enabling a low-carbon energy system. Deep saline aquifers (DSAs) offer substantial theoretical capacity and broad geographic distribution making them attractive options for underground hydrogen storage. However hydrogen storage in DSAs presents complex technical geochemical microbial geomechanical and economic challenges that must be addressed to ensure efficiency safety and recoverability. This study synthesizes current knowledge on hydrogen behavior in DSAs focusing on multiphase flow dynamics capillary trapping fingering phenomena geochemical reactions microbial consumption cushion gas requirements and operational constraints. Advanced numerical simulations and experimental observations highlight the role of reservoir heterogeneity relative permeability hysteresis buoyancy-driven migration and redox-driven hydrogen loss in shaping storage performance. Economic analysis emphasizes the significant influence of cushion gas volumes and hydrogen recovery efficiency on the levelized cost of storage while pilot studies reveal strategies for mitigating operational and geochemical risks. The findings underscore the importance of integrated coupled-process modeling and comprehensive site characterization to optimize hydrogen storage design and operation. This work provides a roadmap for developing scalable safe and economically viable hydrogen storage in DSAs bridging the gap between laboratory research pilot demonstration and commercial deployment.

This study presents a comprehensive review of the viability of hydrogen as an energy carrier for offshore wind energy compared to existing electricity carrier systems. To enable a state-of-the-art system comparison a review of wind-to-hydrogen energy conversion and transmission systems is conducted alongside wind-to-electricity systems. The review reveals that the wind-to-hydrogen energy conversion and transmission system becomes more cost-effective than the wind-to-electricity conversion and transmission system for offshore wind farms located far from the shore. Electrical transmission systems face increasing technical and economic challenges relative to the hydrogen transmission system when the systems move farther offshore. This study also explores the feasibility of using seawater for hydrogen production to conserve freshwater resources. It was found that while this approach conserves freshwater and can reduce transportation costs it increases overall system costs due to challenges such as membrane fouling in desalination units. Findings indicated that for this approach to be sustainable proper management of these challenges and responsible handling of saline waste are essential. For hydrogen energy transmission this paper further explores the potential of repurposing existing oil and gas pipeline infrastructure instead of constructing new pipelines. Findings indicated that with proper retrofitting the existing natural gas pipelines could provide a cost-effective and environmentally sustainable solution for hydrogen transport in the near future.

This paper explores how the deployment of “High-Performance Heat-Powered Heat Pumps” (HP3 s)—a novel heating technology—could help meet the domestic heating demand in the UK and reduce how much grid-scale energy storage is needed in comparison to a scenario where electrical heat pumps fully supply the heating demand. HP3 systems can produce electricity which can partially alleviate the stress caused by electrical heat pumps. A parametric analysis focusing on two variables the penetration of HP3 systems (H) and the amount of electricity exported (Ɛ) is presented. For every combination of H and Ɛ the electricity system is optimized to minimize the cost of electricity. Three parameters define the electricity system: the generation mix the energy storage mix and the amount of over-generation. The cost of electricity is at its highest when electrical heat pumps supply all demand. This reduces as the penetration of HP3 systems increases due to a reduction in the need for energy storage. When HP3 systems supply 100% of the heating demand the total cost of electricity and the storage capacity needed are 6% and 50% lower respectively compared to a scenario where electrical heat pumps are in 100% of residences.

As global efforts to decarbonize intensify hydrogen produced via renewable electricity has emerged as a pivotal energy vector for a sustainable industrial future. This commentary provides a critical analysis of the current state of the hydrogen economy in Europe detailing the core principles operational mechanisms and industrial status of four primary water electrolysis technologies: alkaline (ALK) proton exchange membrane (PEM) solid oxide (SOEC) and anion exchange membrane (AEM). Furthermore it explores the significant socio-political challenges inherent in producing green hydrogen in non-EU nations for subsequent import into the European market.

Coal constitutes China’s most significant resource endowment at present. Utilizing coal resources for hydrogen production represents an early-stage pathway for China’s hydrogen production industry. The analysis of energy quality and carbon emissions in coal gasification-based hydrogen production holds practical significance. This paper integrates the exergy analysis methodology into the traditional LCA framework to evaluate the exergy and carbon emission scales of coal gasification-based hydrogen production in China considering the technical conditions of CCUS. This paper found that the life cycle exergic efficiency of the whole chain of gasification-based hydrogen production in China is accounted to be 38.8%. By analyzing the causes of exergic loss and energy varieties it was found that the temperature difference between the reaction of coal gasification and CO conversion unit and the pressure difference due to the compressor driven by the electricity consumption of the compression process in the variable pressure adsorption unit are the main causes of exergic loss. Corresponding countermeasures were suggested. Regarding decarbonization strategies the CCUS process can reduce CO2 emissions across the life cycle of coal gasification-based hydrogen production by 48%. This study provides an academic basis for medium-to-long-term forecasting and roadmap design of China’s hydrogen production structure.

The adoption of hydrogen as a clean energy carrier depends heavily on the development of materials capable of enduring the extreme conditions associated with its production storage and transportation. This review critically evaluates the performance of metals polymers and composites in hydrogen-rich environments focusing on degradation mechanisms such as hydrogen embrittlement rapid gas decompression and long-term fatigue. Metals like carbon steels and high-strength alloys can experience a 30–50 % loss in tensile strength due to hydrogen exposure while polymers suffer from permeability increases and sealing degradation. Composite materials though strong and lightweight may lose up to 15 % of their mechanical properties over time in hydrogen environments. The review highlights current mitigation strategies including hydrogen-resistant alloys polymer blends protective coatings composite liners and emerging technologies like predictive modeling and AI-based material design. With hydrogen production expected to reach 500 GW globally by 2030 improving material compatibility and developing international standards are essential for scaling hydrogen infrastructure safely and cost-effectively. This work presents an integrated analysis of material degradation mechanisms highlights key challenges across metals polymers and composites in hydrogen environments and explores recent innovations and future strategies to enhance durability and performance in hydrogen infrastructure.

Clean energy technologies offer promising pathways for low-carbon transitions yet their feasibility remains uncertain particularly in rapidly developing regions. This study develops a Factorial Multi-Stochastic Optimization-driven Equilibrium (FMOE) model to assess the economic and environmental impacts of clean power deployment. Using Small Modular Reactors (SMRs) in Guangdong China as a case study the model reveals that SMRs can reduce system costs and alleviate GDP losses supporting provincial-level Nationally Determined Contributions (NDCs). If offshore wind capital costs fall to 40 % of SMRs’ SMR deployment may no longer be necessary after 2030. Otherwise SMRs could supply 22 % of capacity by 2040. The FMOE model provides a robust adaptable framework for evaluating emerging technologies under uncertainty and supports sustainable power planning across diverse regional contexts. This study offers valuable insights into the resource and economic implications of clean energy strategies contributing to global carbon neutrality and efficient energy system design.

This study presents a cross-national investigation into the drivers and psychological mechanisms shaping public perceptions and acceptance of hydrogen refuelling infrastructure located in residential proximity. Parallel survey data from Japan Spain and Norway were analysed using a multigroup comparative framework. Measurement invariance was established across the three datasets subject to minor modifications within the constructs of trust in hydrogen innovation safe housing concern and perceived usefulness. The conceptual models yielded generalisable findings across countries: negative emotions exerted a stronger influence on individuals' risk perceptions than positive emotions whereas perceived usefulness had a greater impact on acceptance than perceived risk. Safe housing and environmental concerns exhibited moderating effects that amplified the influence of affective responses towards hydrogen refuelling facilities with varying magnitudes across datasets. Furthermore the incorporation of Hofstede's cultural dimensions provided insights into cross-country differences revealing that individualism uncertainty avoidance and long-term orientation explain the psychological pathways through which affective states are translated into subjective evaluations of hydrogen facilities ultimately shaping community acceptance.

Hydrogen (H2) is an attractive fuel due to its high specific energy and zero direct carbon emissions. Membraneless electrolyzers (MEs) offer a lower-cost route to hydrogen production but their operation is complex and current efficiencies are modest. Although multi-objective optimization is widely used its heavy compute demands and weak integration with modern learning methods limit scalability and adaptability. We introduce a practical ML-guided way to design Tesla-valve (TV) membraneless electrolyzers by building diodicity (Di) directly into the geometry search. Using multilayer-perceptron surrogates trained on 150 high-fidelity simulations (R2 > 0.95) we link four design knobs (We Wc Wd Di) to pressure drop (Δp) and ohmic loss. A Genetic Algorithm (GA)-based multi-objective search over realistic ranges delivers 60 Pareto-optimal designs that make the Δp–ohmic trade-off explicit; TOPSIS then selects a balanced geometry (We = 1.708 mm Wc = 0.200 mm Wd = 1.012 mm Di = 1.618) with ohmic loss 4.069 V and Δp 6.169 Pa. The approach delivers faster lower-cost design maps and is supported by experimental checks pointing to an actionable route for scalable interpretable optimization of sustainable hydrogen production.