Applications & Pathways
Transforming Ports for a Low-carbon Future: Nexus Modeling of Hydrogen Infrastructure, Employment, and Resource Management in Contrasting Climates
Aug 2025
Publication
This research study highlights a transformative approach to port development for a lowcarbon future by integrating Climate Land Energy and Water Systems (CLEWs) and Water-Energy-Food (WEF) frameworks. The proposed nexus model integrates the hydrogen infrastructure with green employment and resource management in contrasting climates. The scenarios analyzed include Business As Usual (BAU) Balanced Reduction Approach (BRA) and Maximal Sustainability Push (MSP) which focuses mainly on energy efficiency resource utilization and workforce sustainability. By BRA it is estimated that carbon emissions will decline by 30% in cold climates and 20% in warm climates without changing renewable power plants producing 45% and 30% of the electricity supply mix. In the MSP scenario emission reductions rise to 90% in cold and 40% in warm climates with renewables providing 62% and 40% of the electricity mix. Under the whole capacity of Municipal Solid Waste (MSW) and fish waste under anaerobic digestion and fish waste rendering by 2040 across all BRA and MSP scenarios. In transport 44% replacement of marine vehicles and 87% of land vehicles with hydrogen electric and carbon capture and storage (CCS)-equipped vehicles is made under the BRA scenario. These percentages increase to 100% under the MSP scenario in cold climates while remaining at 87% in warm climates. By this integrated framework the present study demonstrates the potential of ports to be powerful engines for sustainable economic growth optimized resource efficiency and the creation of resilient green employment systems in diverse environmental contexts.
Exploring the Potential of Ammonia as a Fuel: Advances in Combustion Understanding and Large-scale Furnace Applications
Sep 2025
Publication
From an environmental standpoint carbon-free energy carriers such as ammonia and hydrogen are essential for future energy systems. However their hightemperature chemical behavior remains insufficiently understood posing challenges for the development and optimization of advanced combustion technologies. Ammonia in particular is globally available and cost-effective especially for energy-intensive industries. The addition of ammonia or hydrogen to methane significantly reduces the accuracy of existing predictive models. Therefore validated and detailed data are urgently needed to enable reliable design and performance predictions. This review highlights the compatibility of ammonia with existing combustion infrastructure facilitating a smoother transition to more sustainable heating methods without the need for entirely new systems. Applications in high-temperature heating processes such as metal processing ceramics and glass production and power generation are of particular interest. This review focuses on the systematic assessment of alternative fuel mixtures comprising ammonia and hydrogen as well as natural gas with particular consideration of existing safety-related parameters and combustion characteristics. Fundamental quantities such as the laminar burning velocity are discussed in the context of their relevance for fuel mixtures and their scalability toward turbulent flame propagation which is of critical importance for industrial burner and reactor design. The influence of fuel composition on ignition limits is examined as these are essential parameters for safety margin definitions and operational boundary conditions. Furthermore flame stability in mixed-fuel systems is addressed to evaluate the practical feasibility and robustness of combustion under varying process conditions. A detailed overview of current diagnostic and analysis methods follows encompassing both pollutant measurement techniques and the detection of key radical species. These diagnostics form the experimental basis for reaction kinetics modeling and mechanism validation. Given the importance of emission formation in combustion systems a dedicated subsection summarizes major emission trends even though a comprehensive treatment would exceed the scope of this review. Thermal radiation effects which are highly relevant for heat transfer and system efficiency in large-scale applications are then reviewed. In parallel current developments in numerical simulation approaches for industrial-scale combustion systems are presented including aspects of model accuracy boundary conditions and computational efficiency. The review also incorporates insights from materials engineering particularly regarding high-temperature material performance corrosion resistance and compatibility with combustion products. Based on these interdisciplinary findings operational strategies for high-temperature furnaces are outlined and selected industrial reference systems are briefly presented. This integrated approach aims to support the design optimization and safe operation of next-generation combustion technologies utilizing carbon-free or low-carbon fuels.
Catalytic Hydrogen Combustion as Heat Source for the Dehydrogenation of Liquid Organic Hydrogen Carriers using a Novel Compact Autothermal Reactor
Sep 2025
Publication
The experimental performance of an autothermal hydrogen release unit comprising a perhydro benzyltoluene (H12-BT) dehydrogenation chamber and a catalytic hydrogen combustion (CHC) chamber in thermal contact is discussed. In detail the applied set-up comprised a multi-tubular CHC heating based on seven parallel tubes with the reactor shell containing a commercial dehydrogenation catalyst. In this way the CHC heated the endothermal LOHC dehydrogenation using a part of the hydrogen generated in the dehydrogenation. The proposed heating concept for autothermal LOHC dehydrogenation offers several advantages over state-of-the-art heating concepts including minimized space consumption high efficiency and zero NOx emissions. During performance tests the process reached a minimum hydrogen combustion fraction of 37 % while the minimum heat requirement for the dehydrogenation reaction for industrial scale plants is 33 %. The reactor orientation (vertical vs horizontal) and the flow configuration (counter-current vs. co-current) showed very little influence on the performance demonstrating the robustness of the proposed reactor design.
The Concept of an Infrastructure Location to Supply Buses with Hydrogen: A Case Study of the West Pomeranian Voivodeship in Poland
Jun 2025
Publication
The growing energy crisis and increasing threat of climate change are driving the need to take action regarding the use of alternative fuels in transport including public transport. Hydrogen is undoubtedly a fuel which is environmentally friendly and constitutes an alternative to fossil fuels. The wider deployment of hydrogen-powered vehicles involves the need to adapt infrastructure to support the operation of these vehicles. Such infrastructure includes refuelling stations for hydrogen-powered vehicles. The widespread use of hydrogen-powered vehicles is dependent on the development of a network of hydrogen refuelling stations. The aim of this article is to propose the conceptual location of infrastructure for fuelling public transport vehicles with hydrogen in selected cities of the West Pomeranian Voivodeship in particular the cities of Szczecin and Koszalin. The methodology used to determine the number of refuelling stations is described and the concept of the location for the refuelling stations has been proposed. Based on a set assumptions it was stated that two stations may be located in the Voivodeship in 2025 and seven stations in 2040. The research results will be of interest to infrastructure developers public transport companies and municipalities involved in making decisions related to the purchase and operation of hydrogen-powered buses.
Prospective Life Cycle Assessment of Future Swedish Hydrogen-powered Aviation Pathways
Jun 2025
Publication
Hydrogen-powered aviation is promoted as a low-carbon alternative for future long-distance air travel but its broader environmental impacts remain unclear. This study evaluates the potential environmental impacts of six future air travel pathways in Sweden including e-kerosene liquid hydrogen and fossil kerosene using prospective life cycle assessment. Results show that hydrogen-powered aviation has lower global warming potential than fossil kerosene but higher impacts on other environmental issues such as toxicity and land use. Key hotspots include resources in energy infrastructure and energy use in fuel production and airport operations however resource substitutions and energy efficiency improvements have limits. This study highlights the potential environmental benefits and tradeoffs of hydrogen-powered aviation and also the dependency of aviation on other sectors. Further research should integrate technological innovations in long-distance air travel pathways with scenarios that account for demand-side measures as well as regulatory political and economic barriers.
The Need for Change: A Roadmap for the Sustainable Transformation of the Chemical Industry
Jun 2025
Publication
The chemical industry faces major challenges worldwide. Since 1950 production has increased 50-fold and is projected to continue growing particularly in Asia. It is one of the most energy- and resource-intensive industries contributing significantly to greenhouse gas emissions and the depletion of finite resources. This development exceeds planetary boundaries and calls for a sustainable transformation of the industry. The key transformation areas are as follows: (1) Non-Fossil Energy Supply: The industry must transition away from fossil fuels. Renewable electricity can replace natural gas while green hydrogen can be used for high-temperature processes. (2) Circularity: Chemical production remains largely linear with most products ending up as waste. Sustainable product design and improved recycling processes are crucial. (3) Non-Fossil Feedstock: To achieve greenhouse gas neutrality oil gas and coal must be replaced by recycling plastics renewable biomaterials or CO2-based processes. (4) Sustainable Chemical Production: Energy and resource savings can be achieved through advancements like catalysis biotechnology microreactors and new separation techniques. (5) Sustainable Chemical Products: Chemicals should be designed to be “Safe and Sustainable by Design” (SSbD) meaning they should not have hazardous properties unless essential to their function. (6) Sufficiency: Beyond efficiency and circularity reducing overall material flows is essential to stay within planetary boundaries. This shift requires political economic and societal efforts. Achieving greenhouse gas neutrality in Europe by 2050 demands swift and decisive action from industry governments and society. The speed of transformation is currently too slow to reach this goal. Science can drive innovation but international agreements are necessary to establish a binding framework for action.
Day-Ahead Dispatch Optimization of an Integrated Hydrogen–Electric System Considering PEMEL/PEMFC Lifespan Degradation and Fuzzy-Weighted Dynamic Pricing
Sep 2025
Publication
Integrated Hydrogen–Energy Systems (IHES) have attracted widespread attention; however distributed energy sources such as photovoltaics (PV) and wind turbines (WT) within these systems exhibit significant uncertainty and intermittency posing key challenges to scheduling complexity and system instability. As a core mechanism for the integrated operation of IHES electricity price regulation can promote the absorption of renewable energy optimize resource allocation and enhance operational economy. Nevertheless uncertainties in IHES hinder the formulation of accurate electricity prices which easily lead to delays in scheduling responses and an increase in cumulative operating costs. To address these issues this study develops lifespan models for Proton Exchange Membrane Electrolyzers (PEMELs) and Proton Exchange Membrane Fuel Cells (PEMFCs) constructs dynamic equations for the demand side and response side and proposes a fuzzy-weighted dynamic pricing strategy. Simulation results show that compared with fixed pricing the proposed dynamic pricing strategy reduces economic indicators by an average of 15.3% effectively alleviates energy imbalance and optimizes the energy supply of components. Additionally it reduces the lifespan degradation of PEMELs by 21.59% and increases the utilization rate of PEMFCs by 54.8%.
Effect of Injection Timing on Gas Jet Developments in a Hydrogen Low-pressure Direct-injection Spark-ignition Engine
Sep 2025
Publication
Injection timing in low-pressure hydrogen direct injection (H2LPDI) engines plays a critical role in optimising gas jet structure and mixture formation due to the complex and transient nature of ambient air flow and density inside the cylinder. This study systematically investigates the macroscopic characteristics of gas jet development at five distinct injection timings from 210 to 120 ◦CA bTDC with the intake valve closure (IVC) as a reference point in a motored inline four-cylinder spark-ignition engine at 2000 rpm and 160 Nm load using low-pressure injection of 3.5 MPa. Optical access was made with two endoscopes: one for high-speed imaging and the other for laser insertion to realise laser shadowgraph imaging of the gas jet delivered using a side-mounted outwardopening pintle nozzle injector. The experimental results reveal spatial and temporal variations in jet morphology penetration spreading angle and mixture dispersion as a function of injection timing. Pre-IVC injection (210 ◦CA bTDC) produced a narrow mean cone angle of ~40◦ and the highest penetration-rate proxy (0.49) whereas postIVC injection (120 ◦CA bTDC) retained a wider ~53◦ cone yet reduced the penetration rate to 0.28 while increasing the sheet-based mixing index from − 0.084 to − 0.106. Pre-IVC injection occurring under low ambient pressure and with active intake airflow was found to produce elongated jets with enhanced penetration and mixing rates though accompanied by substantial cyclic variations. Conversely post-IVC injection was strongly influenced by a fully developed tumble flow which redirected the jet trajectory towards the pent-roof and facilitated mixing through increased turbulence. However the elevated air density constrained the jet penetration. At-IVC injection resulted in a more uniform and stable jet structure. However the lack of convective flow constrained the overall mixing effectiveness. Quantitative analysis of jet spreading angle pixel intensity gradient and centroid movement using 100 consecutive cycles confirms the critical role of injection timing in shaping the gas jet development as suggested by the images.
Flexible Economic Energy Management Including Environmental Indices in Heat and Electrical Microgrids Considering Heat Pump with Renewable and Storage Systems
Oct 2025
Publication
This study discusses energy management in thermal and electrical microgrids while taking heat pumps renewable sources thermal and hydrogen storages into account. The weighted total of the operating cost grid emissions level voltage and temperature deviation function and other factors makes up the objective function of the suggested method. The restrictions include the operationflexibility model of resources and storages micro-grid flexibility limits and optimum power flow equations. Point Estimation Method is used in this work to simulate load energy price and renewable phenomenon uncertainty. A fuzzy decision-making methodology is used to arrive at a compromise solution that satisfies network operators’ operational environmental and financial goals. The innovations of this paper include energy management of various smart microgrids simultaneous modeling of several indicators especially flexibility investigation of optimal performance of resources and storage devices and modeling of uncertainty considering low computational time and an accurate flexibility model. Numerical findings indicate that the fuzzy decision-making approach has the capability to reach a compromise point in which the objective functions approach their minimum values. The integration of the proposed uncertainty modeling with precise flexibility modeling results in a reduction in computational time when compared to stochastic optimization based on scenarios. For the compromise point and uncertainty modeling with PEM by efficiently managing resources and thermal and hydrogen storages scheme is capable of attaining high flexibility conditions. Compared to load flow studies the approach can enhance the operational environmental and economic conditions of smart microgrids by approximately 33–57% 68% and 33–68% respectively under these circumstances.
Preliminary Design of Regional Aircraft—Integration of a Fuel Cell-Electric Energy Network in SUAVE
Mar 2025
Publication
To enable climate-neutral aviation improving the energy efficiency of aircraft is essential. The research project Synergies of Highly Integrated Transport Aircraft investigates cross-disciplinary synergies in aircraft and propulsion technologies to achieve energy savings. This study examines a fuel cell electric powered configuration with distributed electric propulsion. For this a reverse-engineered ATR 72-500 serves as a reference model for calibrating the methods and ensuring accurate performance modeling. A baseline configuration featuring a state-of-the-art turboprop engine with the same entry-into-service is also introduced for a meaningful performance comparison. The analysis uses an enhanced version of the Stanford University Aerospace Vehicle Environment (SUAVE) a Python-based aircraft design environment that allows for novel energy network architectures. This paper details the preliminary aircraft design process including calibration presents the resulting aircraft configurations and examines the integration of a fuel cell-electric energy network. The results provide a foundation for higher fidelity studies and performance comparisons offering insights into the trade-offs associated with hydrogen-based propulsion systems. All fundamental equations and methodologies are explicitly presented ensuring transparency clarity and reproducibility. This comprehensive disclosure allows the broader scientific community to utilize and refine these findings facilitating further progress in hydrogen-powered aviation technologies.
Operational Optimization of Electricity–Hydrogen Coupling Systems Based on Reversible Solid Oxide Cells
Sep 2025
Publication
To effectively address the issues of curtailed wind and photovoltaic (PV) power caused by the high proportion of renewable energy integration and to promote the clean and lowcarbon transformation of the energy system this paper proposes a “chemical–mechanical” dual-pathway synergistic mechanism for the reversible solid oxide cell (RSOC) and flywheel energy storage system (FESS) electricity–hydrogen hybrid system. This mechanism aims to address both short-term and long-term energy storage fluctuations thereby minimizing economic costs and curtailed wind and PV power. This synergistic mechanism is applied to regulate system operations under varying wind and PV power output and electricity–hydrogen load fluctuations across different seasons thereby enhancing the power generation system’s ability to integrate wind and PV energy. An economic operation model is then established with the objective of minimizing the economic costs of the electricity–hydrogen hybrid system incorporating RSOC and FESS. Finally taking a large-scale new energy industrial park in the northwest region as an example case studies of different schemes were conducted on the MATLAB platform. Simulation results demonstrate that the reversible solid oxide cell (RSOC) system—integrated with a FESS and operating under the dual-path coordination mechanism—achieves a 14.32% reduction in wind and solar curtailment costs and a 1.16% decrease in total system costs. Furthermore this hybrid system exhibits excellent adaptability to the dynamic fluctuations in electricity– hydrogen energy demand which is accompanied by a 5.41% reduction in the output of gas turbine units. Notably it also maintains strong adaptability under extreme weather conditions with particular effectiveness in scenarios characterized by PV power shortage.
Sustainable Transition Pathways for Steel Manufacturing: Low-Carbon Steelmaking Technologies in Enterprises
Jun 2025
Publication
Amid escalating global climate crises and the urgent imperative to meet the Paris Agreement’s carbon neutrality targets the steel industry—a leading contributor to global greenhouse gas emissions—confronts unprecedented challenges in driving sustainable industrial transformation through innovative low-carbon steelmaking technologies. This paper examines decarbonization technologies across three stages (source process and end-of-pipe) for two dominant steel production routes: the long process (BF-BOF) and the short process (EAF). For the BF-BOF route carbon reduction at the source stage is achieved through high-proportion pellet charging in the blast furnace and high scrap ratio utilization; at the process stage carbon control is optimized via bottom-blowing O2-CO2-CaO composite injection in the converter; and at the end-of-pipe stage CO2 recycling and carbon capture are employed to achieve deep decarbonization. In contrast the EAF route establishes a low-carbon production system by relying on green and efficient electric arc furnaces and hydrogen-based shaft furnaces. At the source stage energy consumption is reduced through the use of green electricity and advanced equipment; during the process stage precision smelting is realized through intelligent control systems; and at the end-of-pipe stage a closed-loop is achieved by combining cascade waste heat recovery and steel slag resource utilization. Across both process routes hydrogen-based direct reduction and green power-driven EAF technology demonstrate significant emission reduction potential providing key technical support for the low-carbon transformation of the steel industry. Comparative analysis of industrial applications reveals varying emission reduction efficiencies economic viability and implementation challenges across different technical pathways. The study concludes that deep decarbonization of the steel industry requires coordinated policy incentives technological innovation and industrial chain collaboration. Accelerating large-scale adoption of low-carbon metallurgical technologies through these synergistic efforts will drive the global steel sector toward sustainable development goals. This study provides a systematic evaluation of current low-carbon steelmaking technologies and outlines practical implementation strategies contributing to the industry’s decarbonization efforts.
Optimization Framework for Efficient and Robust Renewable Energy Hub Operation
Oct 2025
Publication
This research proposes an advanced optimization framework for renewable energy hubs within integrated electrical and thermal networks aimed at improving energy management. The motivation stems from the need for a more flexible and efficient solution that addresses the variability of renewable energy sources such as wind and bio-waste units while integrating storage solutions like hydrogen and thermal systems. The hypothesis is that combining a market-clearing price model with robust decision-making frameworks can optimize both economic viability and operational efficiency. The methodology adopts a two-tier optimization approach: the upper tier maximizes hub profits and the lower tier minimizes operational costs through a market-clearing price model. The study also incorporates a robust optimization model that accounts for decision-dependent uncertainties with a novel class of polyhedral uncertainty sets used for improved decision-making. Numerical results from case studies demonstrate that the proposed method increases the objective function by approximately 3% and achieves a 25% faster solution time compared to the Benders decomposition approach. These findings support the conclusion that the proposed framework enhances both flexibility and economic performance of energy hubs offering a viable solution for modern energy systems.
Exploring the Gas Permeability of Type IV Hydrogen Storage Cylinder Liners: Research and Applications
Jul 2025
Publication
As hydrogen fuel cell vehicles gain momentum as crucial zero-emission transportation solutions the urgency to address hydrogen permeability through the polymer liner becomes paramount for ensuring the safety efficiency and longevity of Type IV hydrogen storage tanks. This paper synthesizes existing research findings analyzes the influence of different materials and structures on gas permeability elucidates the dissolution and diffusion mechanisms of hydrogen in plastic liners and discusses their engineering applications. We focus on measurement methods influencing factors and improvement strategies for liner gas permeability. Additionally we explore the prospects of Type IV hydrogen storage tanks in fields such as automotive aerospace and energy storage industries. Through this comprehensive review of liner gas permeability critical insights are provided to guide the development of efficient and safe hydrogen storage and transportation systems. These insights are vital for advancing the widespread application of hydrogen energy technology and fostering sustainable energy development significantly contributing to efforts aimed at enhancing the performance and safety of Type IV hydrogen storage tanks.
Injection Strategies in a Hydrogen SI Engine: Parameter Selection and Comparative Analysis
Oct 2025
Publication
Injection strategies play a crucial role in determining hydrogen engine performance. The diversity of these strategies and the limited number of comparative studies highlight the need for further investigation. This study focuses on the analysis parameter selection and comparison of single early and late direct injection single injection with ignition occurring during injection (the so-called jet-guided operation) and dual injection in a hydrogen spark-ignition engine. The applicability and effectiveness of these injection strategies are assessed using contour maps with ignition timing and start of injection as coordinates representing equal levels of key engine parameters. Based on this approach injection and ignition settings are selected for a range of engine operating modes. Simulations of engine performance under different load conditions are carried out using the selected parameters for each strategy. The results indicate that the highest indicated thermal efficiencies are achieved with single late injection while the lowest occur with dual injection. At the same time both dual injection and jet-guided operation provide advantages in terms of knock suppression peak pressure reduction and reduced nitrogen oxide emissions.
Multi-Objective Optimal Energy Management Strategy for Grid-Interactive Hydrogen Refueling Stations in Rural Areas
Mar 2025
Publication
The transportation sector is a significant contributor to global carbon emissions thus necessitating a transition toward renewable energy sources (RESs) and electric vehicles (EVs). Among EV technologies fuel-cell EVs (FCEVs) offer distinct advantages in terms of refueling time and operational efficiency thus rendering them a promising solution for sustainable transportation. Nevertheless the integration of FCEVs in rural areas poses challenges due to the limited availability of refueling infrastructure and constraints in energy access. In order to address these challenges this study proposes a multi-objective energy management model for a hydrogen refueling station (HRS) integrated with RESs a battery storage system an electrolyzer (EL) a fuel cell (FC) and a hydrogen tank serving diverse FCEVs in rural areas. The model formulated using mixed-integer linear programming (MILP) optimizes station operations to maximize both cost and load factor performance. Additionally bi-directional trading with the power grid and hydrogen network enhances energy flexibility and grid stability enabling a more resilient and self-sufficient energy system. To the best of the authors’ knowledge this study is the first in the literature to present a multi-objective optimal management approach for grid-interactive renewablesupported HRSs serving hydrogen-powered vehicles in rural areas. The simulation results demonstrate that RES integration improves economic feasibility by reducing costs and increasing financial gains while maximizing the load factor enhances efficiency cost-driven strategies that may impact stability. The impact of the EL on cost is more significant while RES capacity has a relatively smaller effect on cost. However its influence on the load factor is substantial. The optimization of RES-supported hydrogen production has been demonstrated to reduce external dependency thereby enabling surplus trading and increasing financial gains to the tune of USD 587.83. Furthermore the system enhances sustainability by eliminating gasoline consumption and significantly reducing carbon emissions thus supporting the transition to a cleaner and more efficient transportation ecosystem.
Net-Zero Backup Solutions for Green Ammonia Hubs Based on Hydrogen Power Generation
Jun 2025
Publication
This paper explores cleaner and techno-economically viable solutions to provide electricity heat and cooling using green hydrogen (H2) and green ammonia (NH3) across the entire decarbonized value chain. We propose integrating a 100% hydrogen-fueled internal combustion engine (e.g. Jenbacher JMS 420) as a stationary backup solution and comparing its performance with other backup technologies. While electrochemical storage systems or battery energy storage systems (BESSs) offer fast and reliable short-term energy buffering they lack flexibility in relocation and typically involve higher costs for extended backup durations. Through five case studies we highlight that renewable-based energy supply requires additional capacity to bridge longer periods of undersupply. Our results indicate that for cost reasons battery–electric solutions alone are not economically feasible for longterm backup. Instead a more effective system combines both battery and hydrogen storage where batteries address daily fluctuations and hydrogen engines handle seasonal surpluses. Despite lower overall efficiency gas engines offer favorable investment and operating costs in backup applications with low annual operating hours. Furthermore the inherent fuel flexibility of combustion engines eventually will allow green ammonia-based backup systems particularly as advancements in small-scale thermal cracking become commercially available. Future studies will address CO2 credit recognition carbon taxes and regulatory constraints in developing more effective dispatch and master-planning solutions.
Machine Learning-driven Stochastic Bidding for Hydrogen Refueling Station-integrated Virtual Power Plants in Energy Market
Aug 2025
Publication
Virtual power plants (VPPs) are gaining significance in the energy sector due to their capacity to aggregate distributed energy resources (DERs) and optimize energy trading. However their effectiveness largely depends on accurately modeling the uncertain parameters influencing optimal bidding strategies. This paper proposes a deep learning-based forecasting method to predict these uncertain parameters including solar irradiation temperature wind speed market prices and load demand. A stochastic programming approach is introduced to mitigate forecasting errors and enhance accuracy. Additionally this research assesses the flexibility of VPPs by mapping the flexible regions to determine their operational capabilities in response to market dynamics. The study also incorporates power-to‑hydrogen (P2H) and hydrogen-to-power (H2P) conversion processes to facilitate the integration of hydrogen fuel cell vehicles (HFCVs) into VPPs enhancing both technical and economic aspects. A network-aware VPP connected to generation resources storage facilities demand response programming (DRP) vehicle-to-grid technology (V2G) P2H and H2P is used to evaluate the proposed method. The problem is formulated as a convex model and solved using the GUROBI optimizer. Results indicate that a hydrogen refueling station can increase profits by approximately 49 % compared to the base case of directly selling surplus generation from renewable energy sources (RESs) to the market and profits can further increase to roughly 86 % when other DERs are incorporated alongside the hydrogen refueling station.
Double-Layer Optimal Configuration of Wind–Solar-Storage for Multi-Microgrid with Electricity–Hydrogen Coupling
Oct 2025
Publication
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.
Influence of Engine Oils on Pre-Ignition Tendency in a Hydrogen–Kerosene Dual-Fuel Engine
Mar 2025
Publication
Reducing CO2 emissions is an increasingly important goal in general aviation. The dual-fuel hydrogen–kerosene combustion process has proven to be a suitable technology for use in small aircraft. This robust and reliable technology significantly reduces CO2 emissions due to the carbon-free combustion of hydrogen during operation while pure kerosene or sustainable aviation fuel (SAF) can be used in safety-critical situations or in the event of fuel supply issues. Previous studies have demonstrated the potential of this technology in terms of emissions performance and efficiency while also highlighting challenges related to abnormal combustion phenomena such as knocking and pre-ignition which limit the maximum achievable hydrogen energy share. However the causes of such phenomena—especially regarding the role of lubricating oils—have not yet been sufficiently investigated in hydrogen engines making this a crucial area for further development. In this paper investigations at the TU Wien Institute of Powertrain and Automotive Technology concerning the role of different engine oils in influencing pre-ignition tendencies in a hydrogen–kerosene dual-fuel engine are described. A specialized test procedure was developed to account for the unique combustion characteristics of the dual-fuel process along with a detailed purge procedure to minimize oil carryover. Multiple engine oils with varying compositions were tested to evaluate their influence on pre-ignition tendencies with a particular focus on additives containing calcium magnesium and molybdenum known for their roles in detergent and anti-wear properties. Additionally the study addressed the contribution of particles to pre-ignition occurrences. The results indicate that calcium and magnesium exhibit no notable impact on pre-ignition behavior; however the addition of molybdenum results in a pronounced reduction in pre-ignition events which could enable a higher hydrogen energy share and thus decrease CO2 emissions in the context of hydrogen dual-fuel aviation applications.
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