Publications

Hydrogen-powered unmanned aerial vehicles (UAVs) offer significant advantages such as environmental sustainability and extended endurance demonstrating broad application prospects. However the hydrogen fuel cells face prominent thermal management challenges during flight operations. This study established a numerical model of the fuel cell thermal management system (TMS) for a hydrogen-powered UAV. Computational fluid dynamics (CFD) simulations were subsequently performed to investigate the impact of various design parameters on cooling performance. First the cooling performance of different fan density configurations was investigated. It was found that dispersed fan placement ensures substantial airflow through the peripheral flow channels significantly enhancing temperature uniformity. Specifically the nine-fan configuration achieves an 18.5% reduction in the temperature difference compared to the four-fan layout. Additionally inlets were integrated with the fan-based cooling system. While increased external airflow lowers the minimum fuel cell temperature its impact on high-temperature zones remains limited with a temperature difference increase of more than 19% compared to configurations without inlets. Furthermore the middle inlet exhibits minimal vortex interference delivering superior thermal performance. This configuration reduces the maximum temperature and average temperature by 9.1% and 22.2% compared to the back configuration.

We develop a bidding strategy for a hybrid power plant combining co-located wind turbines and an electrolyzer constructing a price-quantity bidding curve for the day-ahead electricity market while optimally scheduling hydrogen production. Without risk management single imbalance pricing leads to an all-or-nothing trading strategy which we term “betting”. To address this we propose a data-driven pragmatic approach that leverages contextual information to train linear decision policies for both power bidding and hydrogen scheduling. By introducing explicit risk constraints to limit imbalances we move from the all-or-nothing approach to a “trading” strategy where the plant diversifies its power trading decisions. We evaluate the model under three scenarios: when the plant is either conditionally allowed always allowed or not allowed to buy power from the grid which impacts the green certification of the hydrogen produced. Comparing our data-driven strategy with an oracle model that has perfect foresight we show that the risk-constrained data-driven approach delivers satisfactory performance.

This study presents a hybrid power system comprising a fuel cell (FC) and a lithium-ion battery (LIB) for liquid hydrogen (LH2) carriers which is expected to increase globally due to the production cost gap of green hydrogen between renewable-rich and renewable-poor countries. The LH2 carrier has a key challenge in handling the inevitably considerable boil-off hydrogen (BOH). As a target ship of a 50000 m3 LH2 carrier with a boil-off rate (BOR) of 0.4% per day this study employs an optimization tool to determine the economic power dispatch between the FC and LIB aimed at minimizing the lifetime cost of the ship. The BOH is used as fuel for FC during the voyage. Moreover when the ship is under cargo loading and unloading operations at the port the considerable surplus BOH is utilized to generate electricity and then sold to the shore grid (StG). The results indicate that 45.2% of the BOH can be utilized as fuel for the FC and the StG system can effectively reduce the total lifetime cost by 32.0%. Further the paper presents the outcomes of a sensitivity analysis conducted on critical parameters. This study provides new insights into the BOH issue of LH2 carriers and helps to increase the international green hydrogen market.

Recent studies on additive manufacturing (AM) have indicated the necessity of understanding the hydrogen embrittlement (HE) of high-strength steels fabricated by AM due to the different microstructure obtained compared to their conventionally processed counterparts. This study investigated the influence of post-AM tempering (at 205 ◦C 315 ◦C and 425 ◦C) on the HE resistance of AM-fabricated AISI 4340 steel a representative ultrahigh-strength medium-carbon low-alloy steel. The present results show that tempering effectively reduced the HE sensitivity of the steel. When tested in air tempering at a low temperature of 205 ◦C slightly increased both the yield strength (YS) and ultimate tensile strength (UTS) accompanied by a reduction in elongation (EL). This behaviour is attributed to the precipitation of carbides. In contrast higher tempering temperatures of 315 ◦C and 425 ◦C resulted in a progressive decrease in both YS and UTS as anticipated. However when tested in a hydrogen-rich environment although the HE dramatically reduced the ductility and YS could not even be determined for the samples tempered at 205 ◦C and 315 ◦C the tempered samples retained higher UTS and EL compared to the as-AM-fabricated samples because of the increased HE resistance by tempering. Microstructural examination indicated that tempering at 205 ◦C and 315 ◦C retained the bainitic microstructure while promoting the formation of fine carbide precipitates which softened the bainitic ferrite matrix enhancing the hydrogen trapping capacity. Tempering at 425 ◦C promoted recovery of the AM-fabricated steel reducing dislocation density producing a lower subsurface hydrogen concentration and higher hydrogen diffusivity which led to an enhanced HE resistance. As a result testing of the samples tempered at 425 ◦C in hydrogen resulted in a high YS (~1200 MPa) and only a ~5 % reduction in UTS and a 64 % reduction in EL compared with the untempered samples of which the reductions were 31 % in UTS and 79 % in EL. Furthermore this study underscores the critical role of the trap character in governing the HE behaviour offering a pathway toward optimised heat treatment strategies for improved HE resistance of additively manufactured high-strength steels.

A compact hydrogen supply system for thermally integrating metal hydride (MH) tanks with a proton exchange membrane fuel cell (PEMFC) for a hydrogen-powered electric-assist bicycle (H-bike) is proposed. The system recovers the exhaust heat generated by the PEMFC to sustain hydrogen desorption and improve the system’s energy efficiency. The results demonstrate that the split-tank strategy decreases thermal and pressure gradients and enhances heat transfer and hydrogen release. The honeycomb tank configuration further improves hydrogen desorption by promoting uniform airflow distribution around each tank thereby improving exhaust heat utilization from the PEMFC. It employs a layer-adjustable configuration facilitating the flexible adaptation of MH cartridge quantities to meet hydrogen demand and prevailing road conditions in urban areas. Under a PEMFC power output of 215 W the system maintains a stable hydrogen flow rate for over 30 min with a heat recovery efficiency of 22.62 %. Furthermore increasing the number of MH cartridge layers significantly improves the thermal utilization of the system achieving a utilization efficiency of 39.90 % with two layers. These findings confirm the feasibility and scalability of the proposed system for H-bike highlighting its potential as a decentralized hydrogen supply solution for lightweight mobility and urban transportation applications.

Hydrogen plasma offers an emerging route for carbon-free iron oxide reduction but typical inert gas dilution limits industrial applicability. This study explores pure hydrogen and hydrogen–carbon dioxide plasma for in-flight hematite reduction in atmospheric elongated arc discharge. Pure hydrogen yields the lowest power consumption but reduced plasma stability and limited conversion. CO2 addition enhances stability increasing gas temperature from approximately 1900 K (pure H2 ) to 2900 K at 50% CO2 driven by exothermic H2 oxidation. Particle rapidly reach gas temperature (>2000 K within 5 ms). The highest metallization degree (≈37%) achieved at 30% CO2 corresponds to an optimal reductant gas composition balancing hydrogen carbon monoxide and atomic hydrogen availability. Higher dilution (50% CO2 ) significantly decreased the reductant gas availability lowering the degree of reduction despite higher temperatures. These insights demonstrate that controlled CO2 co-feeding and regeneration optimize plasma stability temperature and reductant gas chemistry presenting a promising approach towards scalable and energy-efficient hydrogen plasma smelting reduction for sustainable metallurgy with a CO2 closed loop.

Improving the efficiency and range of hydrogen-powered electric vehicles (HPEVs) is essential for their global adoption especially in developing countries with limited resources. This study systematically evaluates regenerative braking and suspension systems in HPEVs and proposes a deployment-focused framework tailored to the needs of developing nations. A comprehensive search was performed across multiple databases to identify relevant studies. The selected studies are screened assessed for quality and analyzed based on predefined criteria. The data is synthesized and interpreted to identify patterns gaps and conclusions. The findings show that regeneration systems such as regenerative braking and regenerative suspension are the most effective energy recovery systems in most electric and hydrogen-powered vehicles. Although the regenerative braking system (RBS) offers higher energy efficiency gains that enhance cost-effectiveness despite its high initial investment the regenerative suspension system (RSS) involves increased complexity. Still it offers comparatively efficient energy recovery particularly in developing countries with patchy road infrastructure. The gaps highlighted in this review will aid researchers and vehicle manufacturers in designing optimizing developing and commercializing HPEVs for deployment in developing countries.

By turning a waste stream into a clean energy source green hydrogen generation from wastewater provides a dual solution to energy and environmental problems. This study presents a thorough bibliometric analysis of research trends in the field of green hydrogen generation from wastewater between 2010 and 2024. A total of 221 publications were extracted from Scopus database and VOSviewer (1.6.20) was used as a visualization tool to identify influential authors institutions collaborations and thematic focus areas. The analysis revealed a significant increase in research output with a peak of 122 publications in 2024 with a total of 705 citations. China had the most contributions with 60 publications followed by India (30) and South Korea (26) indicating substantial regional involvement in Asia. Keyword co-occurrence and coauthorship network mapping revealed 779 distinct keywords grouped around key themes like electrolysis hydrogen evolution reactions and wastewater treatment. Significantly this work was supported by contributions from 115 publication venues with the International Journal of Hydrogen Energy emerging as the most active and cited source (40 articles 539 citations). The multidisciplinary aspect of the area was highlighted by keyword co-occurrence analysis which identified recurring themes including electrolysis wastewater treatment and hydrogen evolution processes. Interestingly the most-cited study garnered 131 citations and discussed the availability of unconventional water sources for electrolysis. Although there is growing interest in the field it is still in its initial phases indicating a need for additional research particularly in developing countries. This work offers a basic overview for researchers and policymakers who are focused on promoting the sustainable generation of green hydrogen from wastewater.

Photocatalytic membrane reactors (PMRs) which combine photocatalysis with membrane separation represent a pivotal technology for sustainable water treatment and resource recovery. Although extensive research has documented various configurations of photocatalytic-membrane hybrid processes and their potential in water treatment applications a comprehensive analysis of the interrelationships among reactor architectures intrinsic physicochemical mechanisms and overall process efficiency remains inadequately explored. This knowledge gap hinders the rational design of highly efficient and stable reactor systems—a shortcoming that this review seeks to remedy. Here we critically examine the connections between reactor configurations design principles and cutting-edge applications to outline future research directions. We analyze the evolution of reactor architectures relevantreaction kinetics and key operational parameters that inform rational design linking these fundamentals to recent advances in solar-driven hydrogen production CO2 conversion and industrial scaling. Our analysis reveals a significant disconnect between the mechanistic understanding of reactor operation and the system-level performance required for innovative applications. This gap between theory and practice is particularly evident in efforts to translate laboratory success into robust and economically feasible industrial-scale operations. We believe that PMRs willrealize theirtransformative potential in sustainable energy and environmental applications in future.

The main component of the hydrogen production system is the electrolyzer (EL) which is used to convert electrical energy and water into hydrogen and oxygen. The power converter supplies the EL and the controller is used to ensure the global stability and safety of the overall system. This review aims to investigate and analyze each one of these components: Proton Exchange Membrane Electrolyzer (PEM EL) electrical modeling DC/DC power converters and control approaches. To achieve this desired result a review of the literature survey and an investigation of the PEM EL electrical modeling of the empirical and semi-empirical including the static and dynamic models are carried out. In addition other sub-models used to predict the temperature gas flow rates (H2 and O2 ) hydrogen pressure and energy efficiency for PEM EL are covered. DC/DC power converters suitable for PEM EL are discussed in terms of efficiency current ripple voltage ratio and their ability to operate in the case of power switch failure. This review involves analysis and investigation of PEM EL control strategies and approaches previously used to achieve control objectives robustness and reliability in studying the DC/DC converter-PEM electrolyzer system. The paper also highlights the online parameter identification of the PEM electrolyzer model and adaptive control issues. Finally a discussion of the results is developed to emphasize the strengths weaknesses and imperfections of the literature on this subject as well as proposing ideas and challenges for future work.

Solid oxide fuel cells (SOFC) have not received enough attention as a power source in the transportation sector. However with the development of the technology its advantages over other types of fuel cells such as fuel flexibility and high energy efficiency have made SOFC an interesting option. The present study aims at simulation and experimentally validation of the performance of a hydrogen-powered SOFC in an automotive application. A 6 kW SOFC stack is tested and its model is integrated into a series hybrid electric vehicle model. A fuzzy controller is designed to regulate the charging current between the battery and the SOFC in the vehicle model. Experimental tests are also conducted in a few cases on the SOFC based on the simulation results. The performance of the real SOFC stack is then analysed under dynamic loads to see how the desired current is provided in practice. The results demonstrate a good performance of the SOFC stack under variable load conditions.

This article proposes a novel open-circuit switch fault diagnosis method (FDM) for a three-level interleaved buck converter (TLIBC) in a hydrogen production system based on the water electrolysis process. The control algorithm is suitably modified to ensure the same hydrogen production despite the fault. The TLIBC enables the interfacing of the power source (i.e. low-carbon energy sources) and electrolyzer while driving the hydrogen production of the system in terms of current or voltage. On one hand the TLIBC can guarantee a continuity of operation in case of power switch failures because of its interleaved architecture. On the other hand the appearance of a power switch failure may lead to a loss of performance. Therefore it is crucial to accurately locate the failure in the TLIBC and implement a fault-tolerant control strategy for performance purposes. The proposed FDM relies on the comparison of the shape of the input current and the pulse width modulation (PWM) gate signal of each power switch. Finally an experimental test bench of the hydrogen production system is designed and realized to evaluate the performance of the developed FDM and fault-tolerant control strategy for TLIBC during post-fault operation. It is implemented with a real-time control based on a MicroLabBox dSPACE (dSPACE Paderborn Germany) platform combined with a TI C2000 microcontroller. The obtained simulation and experimental results demonstrate that the proposed FDM can detect open-circuit switch failures in one switching period and reconfigure the control law accordingly to ensure the same current is delivered before the failure.

In the search of low-carbon hydrogen production routes this study evaluates four biomass gasification processes: conventional steam gasification (CSG) sorption-enhanced gasification (SEG) and their solar-assisted variants (SSG and SSEG). The comparison focuses on three key aspects: hydrogen production overall energy efficiency (to H2 and power) and carbon capture potential (generation of a pure CO2 process stream for storage or utilization). For a realistic comparison a pseudo-equilibrium model of a double-bed gasifier was developed based on experimental correlations of char conversion under conventional and SEG conditions. The solar processes were designed for stable year-round operation considering seasonal weather variations by appropriately dimensioning the heliostat field and the thermal and chemical energy storage systems whose inventory dynamics were modelled. Both the gasifier and central solar tower models were rigorously validated with published data enhancing the reliability of the results. Solar-assisted configurations significantly outperform non-solar ones in hydrogen production with SSEG yielding 128 kg H2/ton biomassdaf compared to 90–95 kg for non-solar options. SEG demonstrates superior carbon capture potential (76 %) while solar-assisted systems achieve higher energy efficiency (67–73 % vs. 60–63 % for non-solar). These results underscore the potential of solar-assisted gasification for sustainable hydrogen production offering enhanced yields improved efficiency and substantial carbon capture capabilities. Future work will involve economic and environmental analysis to determine the best overall configuration.

Hydrogen is a sustainable clean source of energy and a viable alternative to carbon-based fossil fuels. To support the transport sector’s transition from fossil fuels to hydrogen a hydrogen refuelling station network is being developed to refuel hydrogen-powered vehicles. However hydrogen’s inherent properties present a significant safety challenge and there have been several hydrogen incidents noted with severe impacts to people and assets reported from operational hydrogen refuelling stations worldwide. This paper presents the outcome of an analysis of hydrogen incidents that occurred at hydrogen refuelling stations. For this purpose the HIAD 2.1 and H2tool.org databases were used for the collection of hydrogen incidents. Forty-five incidents were reviewed and analysed to determine the frequent equipment failures in the hydrogen refuelling stations and the underlying causes. This study adopted a mixed research approach for the analysis of the incidents in the hydrogen refuelling stations. The analysis reveals that storage tank failures accounted for 40% of total reported incidents hydrogen dispenser failures accounted for 33% compressors accounted for 11% valves accounted for 9% and pipeline failures accounted for 7%. To enable the safe operation of hydrogen refuelling stations hazards must be understood effective barriers implemented and learning from past incidents incorporated into safety protocols to prevent future incidents.

This paper investigates technological pathways for the conversion of coal-fired power plants toward sustainable energy sources using an integrated multi-criteria decisionmaking approach that combines Proknow-C AHP and PROMETHEE. Eight alternatives were identified: full conversion to natural gas full conversion to biomass coal and natural gas hybridization coal and biomass hybridization electricity and hydrogen cogeneration coal and solar energy hybridization post-combustion carbon capture systems and decommissioning with subsequent reuse. The analysis combined bibliographic data (26 scientific articles and 13 patents) with surveys from 14 energy experts using Total Decision version 1.2.1041.0 and Visual PROMETHEE version 1.1.0.0 software tools. Based on six criteria (environmental structural technical technological economic and social) the most viable option was full conversion to natural gas (ϕ = +0.0368) followed by coal and natural gas hybridization (ϕ = +0.0257) and coal and solar hybridization (ϕ = +0.0124). These alternatives emerged as the most balanced in terms of emissions reduction infrastructure reuse and cost efficiency. In contrast decommissioning (ϕ = −0.0578) and carbon capture systems (ϕ = −0.0196) were less favorable. This study proposes a structured framework for strategic energy planning that supports a just energy transition and contributes to the United Nations Sustainable Development Goals (SDGs) 7 and 13 highlighting the need for public policies that enhance the competitiveness and scalability of sustainable alternatives.

The ongoing energy transition and decarbonization efforts have prompted the development of Hybrid Renewable Energy Systems (HRES) capable of integrating multiple generation and storage technologies to enhance energy autonomy. Among the available options hydrogen has emerged as a versatile energy carrier yet most studies have focused either on stationary applications or on mobility seldom addressing their integration withing a single framework. In particular the potential of Metal Hydride (MH) tanks remains largely underexplored in the context of sector coupling where the same storage unit can simultaneously sustain household demand and provide in-house refueling for lightduty fuel-cell vehicles. This study presents the design and analysis of a residential-scale HRES that combines photovoltaic generation a PEM electrolyzer a lithium-ion battery and MH storage intended for direct integration with a fuel-cell electric microcar. A fully dynamic numerical model was developed to evaluate system interactions and quantify the conditions under which low-pressure MH tanks can be effectively integrated into HRES with particular attention to thermal management and seasonal variability. Two simulation campaigns were carried out to provide both component-level and system-level insights. The first focused on thermal management during hydrogen absorption in the MH tank comparing passive and active cooling strategies. Forced convection reduced absorption time by 44% compared to natural convection while avoiding the additional energy demand associated with thermostatic baths. The second campaign assessed seasonal operation: even under winter irradiance conditions the system ensured continuous household supply and enabled full recharge of two MH tanks every six days in line with the hydrogen requirements of the light vehicle daily commuting profile. Battery support further reduced grid reliance achieving a Grid Dependency Factor as low as 28.8% and enhancing system autonomy during cold periods.

Global demand for clean energy carriers like hydrogen (H2) is rising under carbon-reduction policies. While domestic H2 projects are progressing international trade presents significant opportunities for countries with abundant renewables or advanced production capabilities. Yet establishing H2 as a viable global commodity requires overcoming supply chain challenges in flexibility efficiency and cost. This review examines hydrogen supply chain network design (HSCND) studies and highlights key research gaps in export-oriented systems. Current work often focuses on transport technologies but lacks integrated analyses combining technical economic and policy dimensions. Notable gaps include limited research on retrofitting infrastructure for H2 derivatives underexplored roles of ports as export hubs and insufficient evaluation of regulatory frameworks and financial risks. This review proposes a methodological approach to guide HSCND for export supporting data collection and strategic planning. Future research should integrate technical geopolitical and social factors into models backed by methodological innovation and empirical evidence.

Developing cleaner processes via newer technologies will accelerate advancement toward more sustainable energy systems. Hydrogen is an energy carrier and an intermediate molecule in chemical processes. This research investigates an innovative hydrogen production process utilizing a non-thermal Cold Atmospheric Pressure Plasma-based Reformer (CAPR). Exploring environmentally friendly and economically viable pathways for hydrogen production is crucial for addressing climate change and reducing the carbon footprint of industrial processes. The study investigates the conversion of natural gas to hydrogen at ambient temperature and pressure highlighting the ability of plasma-based technology to operate without direct CO2 emissions.<br/>Initially through experimental studies natural gas was passed through the CAPR where the plasma's energetic discharges initiate the reforming process. Subsequently the produced hydrogen along with other light hydrocarbons enters the separation system for producing purified hydrogen. The research focuses on techno-economic analyses and sensitivity assessments to determine the levelized cost of producing hydrogen via a nanosecond plasma-based refining plant and benchmark technologies. Sensitivity analyses identify two primary factors that significantly affect the levelized cost of hydrogen production in a plasma-based reforming system.<br/>The research suggests that instead of producing carbon dioxide and capturing the emitted CO2 utilize processes that do not emit direct CO2. CAPR shows potential for cost competitiveness with conventional hydrogen production methods including steam methane reforming (SMR) and electrolysis. The findings underscore the need for further research to optimize the system's performance and cost-effectiveness positioning CAPR as a potentially transformative technology for the chemical process industry.

Solid oxide electrolysis cells (SOECs) have emerged as a promising technology for efficient energy storage and CO2 utilization via H2O–CO2 co-electrolysis. While most previous studies focused on planar or tubular configurations this work investigated a novel flat tubular SOEC design using a comprehensive 3D multi-physics model developed in COMSOL Multiphysics 5.6. This model integrates charge transfer gas flow heat transfer chemical/electrochemical reactions and structural mechanics to analyze operational behavior and thermo-mechanical stress under different voltages and pressures. Simulation results indicate that increasing operating voltage leads to significant temperature and current density inhomogeneity. Furthermore elevated pressure improves electrochemical performance possibly due to increased reactant concentrations and reduced mass transfer limitations; however it also increases temperature gradients and the maximum first principal stress. These findings underscore that the design and optimization of flat tubular SOECs in H2O–CO2 co-electrolysis should take the trade-off between performance and durability into consideration.

Hydrogen production from natural gas or biogas at different purity levels has emerged as an important technology with continuous development and improvement in order to stand for sustainable and clean energy. Regarding biogas which can be obtained from multiple sources hydrogen production through the steam reforming of methane is one of the most important methods for its energy use. In that sense the role of catalysts to make the process more efficient is crucial normally contributing to a higher hydrogen yield under milder reaction conditions in the final product. The aim of this review is to cover the main points related to these catalysts as every aspect counts and has an influence on the use of these catalysts during this specific process (from the feedstocks used for biogas production or the biodigestion process to the purification of the hydrogen produced). Thus a thorough review of hydrogen production through biogas steam reforming was carried out with a special emphasis on the influence of different variables on its catalytic performance. Also the most common catalysts used in this process as well as the main deactivation mechanisms and their possible solutions are included supported by the most recent studies about these subjects.

The transition to sustainable and smart urban energy systems requires combustion technologies that combine high efficiency with near-zero emissions. Moderate or intense low-oxygen dilution (MILD) combustion has emerged as a promising solution offering volumetric heat release reduced peak temperatures and strong NOX suppression ideal for integrating green hydrogen carriers such as ammonia and ammonia–hydrogen blends into stationary energy systems. While MILD combustion is well-studied for hydrocarbons its application to carbon-free fuels presents challenges including high ignition temperatures low reactivity and potential NOX formation. This review examines the behavior of ammonia-based fuels under MILD conditions mapping combustion regimes across reactor types and operating parameters. To address ignition and stability issues the review also explores plasma-assisted MILD combustion (PAMC). Non-equilibrium plasma (NEP) discharges promote radical generation reduce ignition delay times and enhance flame stability under lean highly diluted conditions. Recent experimental and numerical studies demonstrate that plasma activation can reduce ignition delay times by up to an order of magnitude lower flame lift-off heights by over 30 % in certain configurations and enhance OH radical concentrations and heat release intensity. The extent of these improvements depends on factors such as plasma energy input fuel type and dilution level. This review synthesizes key findings identifies technical gaps and highlights the potential of MILD and PAMC as clean flexible and scalable solutions for low-emission stationary energy generation in smart city environments.

With the rapid development of alternative fuel vehicles (AFVs) and renewable energy sources the increasing coordination between electric vehicles (EVs) and hydrogen vehicles (HVs) in urban coupled powertransportation networks (CPTNs) fosters optimized energy scheduling and enhanced system performance. This study proposes a two-level Stackelberg-Nash game framework for AFV-integrated microgrids in a CPTN to enhance the economic efficiency of microgrid. This framework employs a Stackelberg game model to define the leader-follower relationship between the microgrid operator and the vehicle-to-grid (V2G) aggregator. Nash equilibrium games are established to capture competitive interactions among charging stations (CSs) and among hydrogen refueling stations (HRSs). Furthermore an optimal scheduling model is proposed to minimize microgrid operation costs considering the spatiotemporal dynamics and user preferences of EVs and HVs supported by the proposed dynamic choice model. A game-theoretic pricing and incentive mechanism promotes AFV participation in V2G services enhancing the profitability of CSs and HRSs. Afterward a momentum-enhanced Stackelberg-Nash equilibrium algorithm is developed to address the bi-level optimization problem. Finally numerical simulations validate the effectiveness of the proposed method in improving economic efficiency and reducing operation costs. The proposed approach offers an effective solution for integrating large-scale AFV fleets into sustainable urban energy and transportation systems.

In recent years there has been an increasingly larger fraction of intermittent energy sources. In the northern parts of Europe the main source of intermittent power is wind power. This source of power is low inertia inconsistent and will always fluctuate with different magnitudes leaving a need for balancing. One source of balancing is to have the widespread non-zero inertia combined heat and power stations work as back-up sources. One way to boost the capability of these power sources is by adding an oxyfuel internal hydrogen combustor. To study the effects of this the steam generator was tested in four different positions within the power plant to test different possibilities with different levels of retrofits. The first was in the high- and lowpressure crossover the second was a reheat at a higher pressure the third was a superheat of the admission steam and finally the fourth was a superheat using the overload valves. The final results showed that the configurations of crossover reheat and superheat of admission steam were the best in terms of retrofit while the reheat at higher pressure was deemed the best in terms of backup capacity reaching a gain in power of 9.5 MW at a fuel efficiency of 30.93 %. The highest fuel efficiencies were shown by the latter two amounting to 45.19 % and 51.58 % in district heating mode respectively. There is great potential to be made from these power plants due to the possibility of increased capacity all across Sweden.

This study presents the conceptual design and evaluation of an HRS for light-duty FCEVs. The proposed system integrates wind turbines a water electrolyzer three-stage hydrogen compressor heat recovery and storage a two-stage Organic Rankine Cycle (TS-ORC) hydrogen storage tanks a Vapor Compression Refrigeration Cycle (VCRC) and a hydrogen dispenser. Waste heat from the hydrogen compression process is harnessed to power the TS-ORC where the first stage drives the VCRC and the second stage generates additional electricity. A comprehensive assessment of the system confirmed the system's compliance with the principles of thermodynamics. The results indicate an overall system efficiency of 25.4% and the wind turbines alone achieve 46.21% efficiency. The overall exergy destruction rate of the system is computed to be 2120 kW and the main exergy destruction occurs in wind turbines and water electrolyzer. The first and second stages of the ORC exhibit efficiencies of 14.45% and 6.05% respectively while the VCRC yields a Coefficient of Performance (COP) of 1.24. The specific energy consumption for electrolytic hydrogen production compression and pre-cooling are calculated as 58.83 1.99 and 0.29 kWh/kg respectively. The hydrogen dispenser fills an onboard hydrogen storage tank with a 4 kg capacity at 700 bar in 5.5 min.

The rapid development of fuel cell electric vehicles (FCEVs) has highlighted the critical importance of optimizing energy management strategies to improve vehicle performance energy efficiency durability and reduce hydrogen consumption and operational costs. However existing approaches often face limitations in real-time applicability adaptability to varying driving conditions and computational efficiency. This paper aims to provide a comprehensive review of the current state of FCEV energy management strategies systematically classifying methods and evaluating their technical principles advantages and practical limitations. Key techniques including optimization-based methods (dynamic programming model predictive control) and machine learning-based approaches (reinforcement learning deep neural networks) are analyzed and compared in terms of energy distribution efficiency computational demand system complexity and real-time performance. The review also addresses emerging technologies such as artificial intelligence vehicle-to-everything (V2X) communication and multi-energy collaborative control. The outcomes highlight the main bottlenecks in current strategies their engineering applicability and potential for improvement. This study provides theoretical guidance and practical reference for the design implementation and advancement of intelligent and adaptive energy management systems in FCEVs contributing to the broader goal of efficient and low-carbon vehicle operation.