Publications

The intermittent nature of renewable energy resources such as wind and solar causes the energy supply to be less predictable leading to possible mismatches in the power network. To this end hydrogen production and storage can provide a solution by increasing flexibility within the system. Stored hydrogen as compressed gas can either be converted back to electricity or it can be used as feed-stock for industry heating for built environment and as fuel for vehicles. This research is the first to examine optimal strategies for operating integrated energy systems consisting of renewable energy production and hydrogen storage with direct gas-based use-cases for hydrogen. Using Markov decision process theory we construct optimal policies for day-to-day decisions on how much energy to store as hydrogen or buy from or sell to the electricity market and on how much hydrogen to sell for use as gas. We pay special emphasis to practical settings such as contractually binding power purchase agreements varying electricity prices different distribution channels green hydrogen offtake agreements and hydrogen market price uncertainties. Extensive experiments and analysis are performed in the context of Northern Netherlands where Europe’s first Hydrogen Valley is being formed. Results show that gains in operational revenues of up to 51% are possible by introducing hydrogen storage units and competitive hydrogen market-prices. This amounts to a e126000 increase in revenues per turbine per year for a 4.5 MW wind turbine. Moreover our results indicate that hydrogen offtake agreements will be crucial in keeping the energy transition on track.

This review article deals with the challenge to identify catalyst materials from literature studies for the ammonia decomposition reaction with potential for application in large-scale industrial processes. On the one hand the requirements on the catalyst are quite demanding. Of central importance are the conditions for the primary reaction that have to be met by the catalyst. Likewise the catalytic performance i.e. an ideally quantitative conversion and a high lifetime are critical as well as the consideration of requirements on the product properties in terms of pressure or by-products for potential follow-up processes in this case synthesis gas applications. On the other hand the evaluation of the multitude of literature studies poses difficulties due to significant varieties in catalytic testing protocols.

Unstable hydrogen-air flame behavior randomities are important for industrial safety hydrogen infrastructure safety and nuclear power plant hydrogen safety problems. The paper is devoted to an experimental and theoretical study of the uncertainty in the acceleration of a premixed laminar unstable hydrogen flame. The results of experiments on spherical flame propagation in hydrogen-air mixtures with a hydrogen content of 10 to 60% are presented. The experiments were repeated up to 30 times in the same mixtures. A statistical analysis of the experimental results has been carried out. The scatter of the experimental data depending on the hydrogen content in the mixture was estimated. It was found to be between 8 to 17% for different mixtures with the same flame radius and mixture composition. Similar results were obtained using the numerical integration of the Sivashinsky equation of flame propagation.

Solar-to-hydrogen plants are predominantly based on steam electrolysis. Steam electrolysis requires water electricity and heat. The excess electric energy is generally converted into hydrogen via an electrolyser. The use of waste heat in hydrogen generation process promises energy efficiency improvement and production fluctuation reductions. This work investigates the techno-economic performance of the proposed system which recovers the waste heat from molten carbonate fuel cell and uses solar energy to produce steam. Comparison of thermally assisted solar system with corresponding solar system is done. The fuel cell provides 80% of the required thermal energy. The solar PV array provides the required electricity. The thermally assisted solar-to-hydrogen system annual energy efficiency (38.5 %) is higher than that of solar- to- hydrogen system. The investment cost of the proposed system is 2.4 % higher than that using only solar parabolic trough collector for the same required amount of heat. The advantage is that the fuel cell simultaneously produces electricity and heat. The recovery of waste heat allows getting an annual overall efficiency of 63.2 % for the molten carbonate fuel cell. It yields 2152 MWh of electricity per year. The 1 MW electrolysers annually generates 74 tonnes of hydrogen.

We had investigated feasible measures to reduce CO2 emission and came to conclusion that introduction of new fuel such as hydrogen with near zero CO2 emission is required for achieving Japan’s commitment of 80% CO2 reduction by 2050. Under this background we are proposing and aiming to realize “CO2 free hydrogen chain” utilizing Australian brown coal linked with CCS. In this chain hydrogen produced from brown coal is liquefied and transported to Japan by liquid hydrogen carrier. We have conducted feasibility study of commercial scale “CO2 free hydrogen chain” whose result shows the chain is technically and economically feasible.

The Heads of Terms for the Low Carbon Hydrogen Agreement sets out the government’s proposal for the final hydrogen production business model design. It will form the basis of the Low Carbon Hydrogen Agreement the business model contract between the government appointed counterparty and a low carbon hydrogen producer.<br/>The business model will provide revenue support to hydrogen producers to overcome the operating cost gap between low carbon hydrogen and high carbon fuels. It has been designed to incentivise investment in low carbon hydrogen production and use and in doing so deliver the government’s ambition of up to 10GW of low carbon hydrogen production capacity by 2030.

Low carbon hydrogen is our new home-grown super-fuel which will be vital for our energy security and to meet our legally binding commitment to achieve net zero by 2050. The UK Hydrogen Strategy published in August 2021 outlined a comprehensive roadmap for the development of a thriving UK hydrogen economy over the coming decade. In the British Energy Security Strategy published in April this year the government doubled the UK’s hydrogen production ambition to up to 10GW by 2030. This increased ambition cements our place firmly at the forefront of the global race to develop hydrogen as a secure low carbon replacement for fossil fuels in the transition to greater energy security and net zero. Since the publication of the UK Hydrogen Strategy we have continued to deliver on our commitments setting out new policy and funding for hydrogen across the value chain and bringing together the international community around shared hydrogen objectives to rapidly develop a global hydrogen economy. Hydrogen was a key component of the Net Zero Strategy COP26 and the British Energy Security Strategy. The Hydrogen Investment Package and opening of the £240 million Net Zero Hydrogen Fund in April marked a major step forward in delivering government support to drive further private investment into hydrogen production in the UK. To keep industry informed on the government’s ongoing work to develop the hydrogen economy we committed in the UK Hydrogen Strategy to producing regular updates to the market as our policy develops. In addition to offering an accessible ‘one stop shop’ of government policy development and support schemes these updates will provide industry and investors with further clarity on the direction of travel of hydrogen policy across the value chain so that government and industry can work together most effectively and with the necessary pace to build a world-leading low carbon hydrogen sector in the UK.

With increasing concerns on transportation decarbonization fuel cell hybrid trains (FCHTs) attract many attentions due to their zero carbon emissions during operation. Since fuel cells alone cannot recover the regenerative braking energy (RBE) energy storage devices (ESDs) are commonly deployed for the recovery of RBE and provide extra traction power to improve the energy efficiency. This paper aims to minimize the net hydrogen consumption (NHC) by co-optimizing both train speed trajectory and onboard energy management using a time-based mixed integer linear programming (MILP) model. In the case with the constraints of speed limits and gradients the NHC of co-optimization reduces by 6.4% compared to the result obtained by the sequential optimization which optimizes train control strategies first and then the energy management. Additionally the relationship between NHC and employed ESD capacity is studied and it is found that with the increase of ESD capacity the NHC can be reduced by up to 30% in a typical route in urban railway transit. The study shows that ESDs play an important role for FCHTs in reducing NHC and the proposed time-based co-optimization model can maximize the energy-saving benefits for such emerging traction systems with hybrid energy sources including both fuel cells and ESD.

The geographical understanding of directionality in the literature on mission-oriented innovation systems is still underdeveloped. Therefore this article reflects on whether the allocation of funding for R&D activities to different places can direct innovation systems in space. A placebased approach to the allocation of funding and its effects on innovation systems is developed to analyze how the German national government allocates funding to the national innovation system for hydrogen technologies. The results show that the allocation of funding considers placebased characteristics and has a range of systemic outcomes encompassing the clustering of research activities the specialization of certain places in certain market segments and the in crease of the spatial reach of the national innovation system by integrating left behind places. However the funding contributes insufficiently to market formation at the local and regional scale and is contested due to existing alternative routes that the innovation system could take.

This study aims to help the Department for Business Energy and Industrial Strategy (BEIS) determine whether the government should intervene to enable or require hydrogen-ready industrial boiler equipment. It will do this based on information from existing literature along with qualitative and quantitative information from stakeholder engagement. The study draws on evidence gathered through BEIS’ Call for Evidence (CfE) on hydrogen-ready industrial boilers. The assessment will advance the overall understanding of hydrogen-ready industrial boilers based on four outputs: definitions of hydrogen-readiness comparisons of the cost and resource requirement to install and convert hydrogen-ready industrial boiler equipment supply chain capacity for conversion to hydrogen and estimates of the UK industrial boiler population.

The increasing penetration of renewable energies will make new storage technologies indispensable in the future. Power-to-Gas (PtG) is one long-term storage technology that exploits the existing gas infrastructure. However this technology faces technical economic environmental challenges and questions. This contribution presents the final results of a large research project which attempted to address and provide answers to some of these questions for Baden-Württemberg (south west Germany). Three energy scenarios out to 2040 were defined one oriented towards the Integrated Energy and Climate Protection Concept of the Federal State Government and two alternatives. Timely-resolved load profiles for gas and electricity for 2015 2020 2030 and 2040 have been generated at the level of individual municipalities. The profiles include residential and industrial electrical load gas required for heating (conventional and current-controlled CHP) as well as gas and electricity demand for mobility. The installation of rooftop PV-plants and wind power plants is projected based on bottom up cost-potential analyses which account for some social acceptance barriers. Residential load profiles are derived for each municipality. In times with negative residual load the PtG technology could be used to convert electricity into hydrogen or methane. The detailed analysis of four structurally-different model regions delivered quite different results. While in large cities no negative residual load is likely due to the continuously high demand and strong networks rural areas with high potentials for renewables could encounter several thousand hours of negative residual load. A cost-effective operation of PtG would only be possible under favorable conditions including high full load hours a strong reduction in costs and a technical improvement of efficiency. Whilst these conditions are not expected to appear in the short to mid-term but may occur in the long term in energy systems with very high shares of renewable energy sources

Ammonia is an industrial chemical and the basic building block for the fertilizer industry. Lately attention has shifted towards using ammonia as a carbon-free energy vector due to the ease of transportation and storage in liquid state at − 33 ◦C and atmospheric pressure. This study evaluates the prospects of blue and green ammonia as future energy carriers; specifically the gas switching reforming (GSR) concept for H2 and N2 co-production from natural gas with inherent CO2 capture (blue) and H2 generation through an optimized value chain of wind and solar power electrolysers cryogenic N2 supply and various options for energy storage (green). These longer term concepts are benchmarked against conventional technologies integrating CO2 capture: the Kellogg Braun & Root (KBR) Purifier process and the Linde Ammonia Concept (LAC). All modelled plants utilize the same ammonia synthesis loop for a consistent comparison. A cash flow analysis showed that the GSR concept achieved an attractive levelized cost of ammonia (LCOA) of 332.1 €/ton relative to 385.1–385.9 €/ton for the conventional plants at European energy prices (6.5 €/GJ natural gas and 60 €/MWh electricity). Optimal technology integration for green ammonia using technology costs representative of 2050 was considerably more expensive: 484.7–772.1 €/ton when varying the location from Saudi Arabia to Germany. Furthermore the LCOA of the GSR technology drops to 192.7 €/ton when benefitting from low Saudi Arabian energy costs (2 €/GJ natural gas and 40 €/MWh electricity). This cost difference between green and blue ammonia remained robust in sensitivity analyses where input energy cost (natural gas or wind/solar power) was the most influential parameter. Given its low production costs and the techno-economic feasibility of international ammonia trade advanced blue ammonia production from GSR offers an attractive pathway for natural gas exporting regions to contribute to global decarbonization.

As one kind of clean zero carbon and sustainable energy hydrogen energy has been regarded as the most potential secondary energy. Recently hydrogen refueling station gradually becomes one of important distribution infrastructures that provides hydrogen sources for transport vehicles and other distribution devices. However the highly combustible nature of hydrogen may bring great hazards to environment and human. The safety design of hydrogen usage has been brought to public too. This paper is mainly focused on the hydrogen leakage and dispersion process. A new solver for gaseous buoyancy dispersion process is developed based on OpenFOAM [1]. Thermodynamic and transport properties of gases are updated by library Mutation ++ [2]. For validation two tests of hydrogen dispersion in partially opened space and closed space are presented. Numerical simulation of hydrogen dispersion behavior in hydrogen refueling station is carried out in this paper as well. From the results three phases of injection dispersion and buoyancy can be seen clearly. The profile of hydrogen concentration is tend to be Gaussian in dispersion region. Subsonic H2 jet in stagnant environment is calculated for refueling station the relationship between H2 concentration decay and velocity along the jet trajectory is obtained.

A proton exchange membrane fuel cell (PEMFC) system requires an adequate hydrogen supply and circulation to achieve its expected performance and operating life. An ejector-based hydrogen circulation system can reduce the operating and maintenance costs noise and parasitic power consumption by eliminating the recirculation pump. However the ejector’s hydrogen entrainment capability restricted by its geometric parameters and flow control variability can only operate properly within a relatively narrow range of fuel cell output power. This research introduced the optimal design and operation control methods of a dual-ejector hydrogen supply/circulation system to support the full range of PEMFC system operations. The technique was demonstrated on a 70 kW PEMFC stack with an effective hydrogen entrainment ratio covering 8% to 100% of its output power. The optimal geometry design ensured each ejector covered a specific output power range with maximized entrainment capability. Furthermore the optimal control of hydrogen flow and the two ejectors’ opening and closing times minimized the anode gas pressure fluctuation and reduced the potential harm to the PEMFC’s operation life. The optimizations were based on dedicated computational fluid dynamics (CFD) and system dynamics models and simulations. Bench tests of the resulting ejector-based hydrogen supply/circulation system verified the simulation and optimization results.

Driven by concerns regarding the sustainability of aviation and the continued growth of air traffic increasing interest is given to emerging aircraft technologies. Although new technologies such as battery-electric propulsion systems have the potential to minimise in-flight emissions and noise environmental burdens are possibly shifted to other stages of the aircraft’s life cycle and new socio-economic challenges may arise. Therefore a life-cycle-oriented sustainability assessment is required to identify these hotspots and problem shifts and to derive recommendations for action for aircraft development at an early stage. This paper proposes a framework for the modelling and assessment of future aircraft technologies and provides an overview of the challenges and available methods and tools in this field. A structured search and screening process is used to determine which aspects of the proposed framework are already addressed in the scientific literature and in which areas research is still needed. For this purpose a total of 66 related articles are identified and systematically analysed. Firstly an overview of statistics of papers dealing with life-cycle-oriented analysis of conventional and emerging aircraft propulsion systems is given classifying them according to the technologies considered the sustainability dimensions and indicators investigated and the assessment methods applied. Secondly a detailed analysis of the articles is conducted to derive answers to the defined research questions. It illustrates that the assessment of environmental aspects of alternative fuels is a dominating research theme while novel approaches that integrate socio-economic aspects and broaden the scope to battery-powered fuel-cell-based or hybrid-electric aircraft are emerging. It also provides insights by what extent future aviation technologies can contribute to more sustainable and energy-efficient aviation. The findings underline the need to harmonise existing methods into an integrated modelling and assessment approach that considers the specifics of upcoming technological developments in aviation.

If an affordable infrastructure for low-carbon-intensity hydrogen can be developed then hydrogen is expected to become a key factor in decarbonizing the atmosphere. This research focuses on factors an existing wind farm operator would consider when weighing participating in the electricity market the hydrogen market or both. The solutions depend on the state of technology which is changing rapidly the local market structures the local natural resources and the local pre-existing infrastructure. Consequently this investigation used an assessment approach that examined the variation of net present value. The investigation identified profitability conditions under three different scenarios: 1) Make and sell what makes economic sense at the time of production 2) Use electrolyzer and fuel cell to consume power from the grid at times of low net demand and to produce electricity at times of high net demand 3) Same as #2 but also market hydrogen directly when profitable.

This paper deals with the integration of a Power-to-Power Energy Storage System (P2P-ESS) based on a hydrogen driven micro gas turbine (mGT) for an off-grid application with a continuous demand of 30 kWe for three European cities: Palermo Frankfurt and Newcastle. In the first part of the analysis the results show that the latitude of the location is a very strong driver in determining the size of the system (hence footprint) and the amount of seasonal storage. The rated capacity of the PV plant and electrolyzer are 37%/41% and 58%/64% higher in Frankfurt and Newcastle respectively as compared to the original design for Palermo. And not only this but seasonal storage also increases largely from 3125 kg H2 to 5023 and 5920 kg H2 . As a consequence of this LCOE takes values of 0.86 e/kWh 1.26 e/kWh and 1.5 e/kWh for the three cities respectively whilst round-trip efficiency is approximately 15.7% for the three designs at the 3 cities. Finally with the aim to reduce the footprint and rating of the different systems a final assessment of the system hybridised with battery storage shows a 20% LCOE reduction and a 10% higher round-trip efficiency.

The reduction of greenhouse gas emissions is one of the greatest global challenges through 2050. Besides greenhouse gas emissions air pollution such as nitrogen oxide and particulate matter emissions has gained increasing attention in agglomerated areas with transport vehicles being one of the main sources thereof. Alternative fuels that fulfill the greenhouse gas reduction goals also offer the possibility of solving the challenge of rising urban pollution. This work focuses on the electric drive option for heavy and light duty vehicle freight transport. In this study fuel cell-electric vehicles battery-electric vehicles and overhead catenary line trucks were investigated taking a closer look at their potential to reduce greenhouse gas emissions and air pollution and also considering the investment and operating costs of the required infrastructure. This work was conducted using a bottom-up transport model for the federal state of North Rhine-Westphalia in Germany. Two scenarios for reducing these emissions were analyzed at a spatial level. In the first of these selected federal highways with the highest traffic volume were equipped with overhead catenary lines for the operation of diesel-hybrid overhead trucks on them. For the second spatial scenario the representative urban area of the city of Cologne was investigated in terms of air pollution shifting articulated trucks to diesel-hybrid overhead trucks and rigid trucks trailer trucks and light duty vehicles to battery-electric or fuel cell-electric drives. For the economic analysis the building up of a hydrogen infrastructure in the cases of articulated trucks and all heavy duty vehicles were also taken into account. The results showed that diesel-hybrid overhead trucks are only a cost-efficient solution for highways with high traffic volume whereas battery overhead trucks have a high uncertainty in terms of costs and technical feasibility. In general the broad range of costs for battery overhead trucks makes them competitive with fuel cell-electric trucks. Articulated trucks have the highest potential to be operated as overhead trucks. However the results indicated that air pollution is only partially reduced by switching conventional articulated trucks to electric drive models. The overall results show that a comprehensive approach such as fuel cell-electric drives for all trucks would most likely be more beneficial.

Methanol is a promising new alternative fuel that emits significantly less carbon dioxide than gasoline. Traditionally methanol was produced by gasifying natural gas and coal. Syn-Gas is created by converting coal and natural gas. After that the Syn-Gas is converted to methanol. Alternative renewable energy-to-methanol conversion processes have been extensively researched in recent years due to the traditional methanol production process’s high carbon footprint. Using an electrolysis cell wind energy can electrolyze water to produce hydrogen. Carbon dioxide is a gas that can be captured from the atmosphere and industrial processes. Carbon dioxide and hydrogen are combusted in a reactor to produce methanol and water; the products are then separated using a distillation column. Although this route is promising it has significant cost and efficiency issues due to the low efficiency of the electrolysis cells and high manufacturing costs. Additionally carbon dioxide capture is an expensive process. Despite these constraints it is still preferable to store excess wind energy in the form of methanol rather than sending it directly to the grid. This process is significantly more carbon-efficient and resource-efficient than conventional processes. Researchers have proposed and/or simulated a variety of wind power methods for methanol processes. This paper discusses these processes. The feasibility of wind energy for methanol production and its future potential is also discussed in this paper.

Growing attention to the environmental aspect has urged the effort to reduce CO2 emission as one of the greenhouse gases. The cement industry is one of the biggest CO2 emitters in this world. Alternative fuel is one of the challenging issues in cement production due to the limited fossil fuel resources and environmental concerns. Meanwhile hydrogen (H2) has been reported as a promising non-carbon fuel with ammonia (NH3) as the main candidate for chemical storage methods. In this work an integrated system of cement production with an alternative H2-based fuel is proposed consisting of the dehydrogenation process of NH3 and the H2 combustion to provide the required thermal energy for clinker production. Different catalysts are employed and evaluated to analyze the specific energy input (SEI). The result shows that the conversion rate strongly determines the SEI with minimum SEI (3829.8 MJ t-clinker-1 ) achieved by Ni-Pt-based catalyst at a reaction temperature of 600 ºC. Compared to the conventional fuel of coal the H2-based integrated cement production system shows a significant decrease of 44% in CO2 emission due to carbon-free combustion using H2 as the fuel. The current study on the proposed integrated system of H2-based cement production also provides an initial thermodynamic analysis and basic observation for the adoption of non-carbon-based H2 including the storage system of NH3 in the cement production process.

An integrated renewable system that utilizes solid waste-based biogas is important steps towards the sustainable energy solutions to rural off-grid communities in Bangladesh. In this study a hybrid energy system consisting of photovoltaic modules wind turbines biogas generators fuel cells and electrolyzer-hydrogen tank-based energy storage is optimized using non-dominated sorting genetic algorithm (NSGA-II). The hybrid system is optimized based on the cost of energy and human health damage as objective functions and a fuzzy decision-making technique is employed to determine the optimal solution to the multi-objective approach. Additionally several economic ecological and social indicators are also investigated while meeting a certain load reliability. An energy management strategy has been developed in the MATALB environment to satisfy the community load and the battery-driven electric vehicle load. Results from this comprehensive analysis suggest that the optimal configuration of PV/WT/FC/BG has an energy cost of 0.1634 $/kWh and an ecosystem damage of 0.00098 species.year. The human health damage and the human development index of the optimized system are 0.1732 DALYs and 0.696 DALYs respectively. Additionally the proposed system has a lifecycle emission of 123730 kg CO2-eq/year carbon emission penalties of $1856/year a job creation potential of 30 jobs/MW over the 25 years of project lifetime. The hybrid system oversees solid waste management solutions and provides the community with sustainable energy and vehicle recharge.

This paper examines some specific design issues associated with hydrogen transportation via pipelines based on recent field development study of high-throughput hydrogen pipelines. A mechanical design review is undertaken and the current design practices and challenge are examined first. An array of key parameters considered to have significant bearing on the hydrogen pipeline general mechanical design are considered and assessed including OOR imperfections combined stress and design factors thermal gradients joint mismatch and fabrication fatigue assessment installation specifications and material consideration. Some of these are typically ignored for the conventional pipeline design but open to rationalization for hydrogen charged pipeline systems subject to material embrittlement risk arising from hydrogen absorption. Complementary to the current design standards and as a spur to discussion on the hydrogen pipeline design analysis special considerations and recommendations are proposed on materials specification additional design criteria and construction assessments and their rationale to mitigate material embrittlement with a view to improving hydrogen pipeline design reliability and integrity management potentially leading to some tangible cost saving.

Understanding what people think about hydrogen energy and how this influences their acceptance of the associated technology is a critical area of research. The public’s willingness to adopt practical applications of hydrogen energy such as hydrogen fuel-cell vehicles (HFCVs) is a key factor in their deployment. To analyse the direct and indirect effects of key attitudinal variables that could influence the intention to use HFCVs in Spain an online questionnaire was administered to a representative sample of the Spanish population (N = 1000). A path analysis Structural Equation Model (SEM) was applied to determine the effect of different attitudinal variables. A high intention to adopt HFCVs in Spain was found (3.8 out of 5) assuming their wider availability in the future. The path analysis results indicated that general acceptance of hydrogen technology and perception of its benefits had the greatest effect on the public’s intention to adopt HFCVs. Regarding indirect effects the role of trust in hydrogen technology was notable having significant mediating effects not only through general acceptance of hydrogen energy and local acceptance of hydrogen refuelling stations (HRS) but also through positive and negative emotions and benefits perception. The findings will assist in focusing the future hydrogen communication strategies of both the government and the private (business) sector.

In response to the issues of insufficient flexibility in the operation of hydrogen storage and hydrogen production equipment with poor economic viability when operated independently in the park firstly a comprehensive energy system model for hydrogen storage and power generation which considering the multi-operational conditions of alkaline electrolyzers (ELE) is constructed. This model is integrated into the comprehensive en ergy system of the park as a multi-energy supply device. Multiple park comprehensive energy systems are then interconnected to form a park comprehensive energy system cluster through the sharing of electric energy. Subsequently an operational optimization strategy is proposed to address the issues of electric energy sharing and profit settlement in the park cluster system. This strategy consists of two stages. In the first stage the alternating direction method of multipliers with dynamic step size (DSS-ADMM) is employed to solve the electric energy transaction volume among parks. In the second stage based on the operating costs of the park cluster system under different degrees of electric energy sharing the Shapley value method from cooperative game theory is used to settle park profits. Finally the results indicate that the operational mode of hydrogen storage which considering the multi-operational conditions of alkaline ELE effectively enhances the flexibility in pre paring hydrogen during electrolysis meeting various energy supply needs within the park. The sharing of electric energy among parks promotes the reduction of park operating costs resulting in a 6.05 % decrease in the total cost of the park cluster system. Meanwhile the Shapley value method effectively settles park profits with in dividual parks receiving profits of 1652.9583 ¥ 404.2334 ¥ and 734.7739 ¥ respectively

Hydrogen as a clean fuel offers a practical pathway to achieve net-zero targets. However due to its physical and chemical characteristics there are some safety concerns for large-scale hydrogen utilisation particularly in process safety management. Leakage of gaseous hydrogen especially in semi-confined spaces such as tunnels can lead to catastrophic outcomes including uncontrolled fire and explosion. The current paper describes the outcome of an experimental and numerical study that aims to understand the dispersion of leaked light gas in a semi-confined space to support the adoption of hydrogen. A dispersion chamber with dimensions of 4m × 0.3m × 0.3m was constructed to investigate a baseline gas leakage scenario. To reduce the risk of the experiment in the laboratory helium is utilised as a surrogate for hydrogen. Computational fluid dynamics simulations are con ducted using FLACS-CFD to model the dispersion of leaked gas in different scenarios focusing on the impact of the ventilation velocity leakage rate and slope. The results from comprehensive numerical simulations show that ventilation is a critical safety management measure that can significantly reduce the growth of flammable clouds and mitigate the fire and explosion risk. Even with the lowest ventilation velocity of 0.25 m/s an improvement in the gas concentration level of 29.34% can be achieved in the downstream chamber. The current results will help to further enhance the understanding of hydrogen safety aspects.