Publications

Hydrogen offers an effective pathway for the large‑scale storage of renewable energy. For a tourist city located in a plateau region rich in renewable energy hydrogen shows great potential for reducing carbon emissions and utilizing uncertain renewable energy. Herein the wind–solar–hydrogen stand‑alone and grid‑connected systems in the plateau tourist city of Lijiang City in Yunnan Province are modeled and techno‑economically evaluated by using the HOMER Pro software (version 3.14.2) with the multi‑criteria decision anal‑ ysis models. The system is composed of 5588 kW solar photovoltaic panels an 800 kW wind turbine a 1600 kW electrolyzer a 421 kWh battery and a 50 kW fuel cell. In addi‑ tion to meeting the power requirements for system operation the system has the capacity to provide daily electricity for 200 households in a neighborhood and supply 240 kg of hydrogen per day to local hydrogen‑fueled buses. The stand‑alone system can produce 10.15 × 106 kWh of electricity and 93.44 t of hydrogen per year with an NPC of USD 8.15 million an LCOE of USD 0.43/kWh and an LCOH of USD 5.26/kg. The grid‑connected system can generate 10.10 × 106 kWh of electricity and 103.01 ton of hydrogen annually. Its NPC is USD 7.34 million its LCOE is USD 0.11/kWh and its LCOH is USD 3.42/kg. This study provides a new solution for optimizing the configuration of hybrid renewable en‑ ergy systems which will develop the hydrogen economy and create low‑carbon‑emission energy systems.

Population growth and economic development have significantly increased global energy demand. Hence it has raised concerns about the increase in the consumption of fossil fuels and climate change. The present work introduced a new approach to using carbon-free energy sources such as nuclear and renewable to meet energy demand. The idea of using the Nuclear-Renewable Hybrid Energy System (N-R HES) is suggested as a leading solution that couples a nuclear power plant with renewable energy and hydrogen-based storage systems. For this purpose using a meta-heuristic method based on Newton’s laws the configuration of the N-R HES is optimized from an economic and reliability point of view. The optimal system is selected from among six cases with different subsystems such as wind turbine photovoltaic panel nuclear reactor electrolysis fuel cell and hydrogen storage tank. Furthermore the performance of hydrogen-based energy storage systems such as hightemperature electrolysis (HTE) and low-temperature electrolysis (LTE) is evaluated from technical and economic aspects. The results of this work showed that using nuclear energy to supply the base load increases the reliability of the system and reduces the loss of power supply probability to zero. More than 70 % of the power is produced by nuclear reactors which includes more than 80 % of the system costs. The key findings showed that despite HTE’s higher efficiency using LTE as a storage system in N-R HES is more cost-effective. Finally due to recent developments and the safer design of nuclear reactors they can play an important role in combination with renewable energies to support carbon-free energy sectors especially in remote areas for decades to come.

Methanol reforming is considered to be one of the most promising hydrogen production technologies for hydrogen fuel cells. It is expected to solve the problem of hydrogen storage and transportation because of its high hydrogen production rate low cost and good safety. However the strong nonlinearity and slow response of the pressure and temperature subsystems pose challenges to the tracking control of the methanol reforming hydrogen production system. In this paper two internal model-based temperature and pressure controllers are proposed in which the temperature is adjusted by controlling the air flow and the pressure is adjusted by controlling the opening of the backpressure valve. Firstly a lumped parameter model of the methanol reforming hydrogen production system is constructed using MATLAB/Simulink® (produced by MathWorks in Natick Massachusetts USA). In addition the transfer function model of the system is obtained by system identification at the equilibrium point and the internal model controller is further designed. The simulation results show that the control method achieves the robustness of the system and the temperature and pressure of the reforming reactor can quickly and accurately track the target value when the load changes. Small-load step tests indicate stable tracking of the temperature and pressure for the reforming reactor without steady-state errors. Under large-temperature step signal testing the response time for the reforming temperature is about 148 s while the large-pressure step signal test shows that the response time for the reforming pressure is about 8 s. Compared to the PID controller the internal model controller exhibits faster response zero steady-state error and no overshoot. The results show that the internal model control method has strong robustness and dynamic characteristics.

Sustainability goals include the utilization of renewable energy resources to supply the energy needs in addition to wastewater treatment to satisfy the water demand. Moreover hydrogen has become a promising energy carrier and green fuel to decarbonize the industrial and transportation sectors. In this context this research investigates a wind-photovoltaic power plant to produce green hydrogen for hydrogen refueling station and to operate an electrocoagulation water treatment unit in Ostrava Czech Republic’s northeast region. The study conducts a techno-economic analysis through HOMER Pro® software for optimal sizing of the power station components and to investigate the economic indices of the plant. The power station employs photovoltaic panels and wind turbines to supply the required electricity for electrolyzers and electrocoagulation reactors. As an offgrid system lead acid batteries are utilized to store the surplus electricity. Wind speed and solar irradiation are the key role site dependent parameters that determine the cost of hydrogen electricity and wastewater treatment. The simulated model considers the capital operating and replacement costs for system components. In the proposed system 240 kg of hydrogen as well as 720 kWh electrical energy are daily required for the hydrogen refueling station and the electrocoagulation unit respectively. Accordingly the power station annually generates 6997990 kWh of electrical energy in addition to 85595 kg of green hydrogen. Based on the economic analysis the project’s NPC is determined to be €5.49 M and the levelized cost of Hydrogen (LCH) is 2.89 €/kg excluding compressor unit costs. This value proves the effectiveness of this power system which encourages the utilization of green hydrogen for fuel-cell electric vehicles (FCVs). Furthermore emerging electrocoagulation studies produce hydrogen through wastewater treatment increasing hydrogen production and lowering LCH. Therefore this study is able to provide practicable methodology support for optimal sizing of the power station components which is beneficial for industrialization and economic development as well as transition toward sustainability and autonomous energy systems.

The present work demonstrates a comparative study of hydrogen fuel cells and combustion aircraft to investigate the potential of fuel cells as a visionary propulsion system for radically more sustainable medium- to long-range commercial aircraft. The study which considered future airframe and propulsion technologies under the Se2A project was conducted to quantify potential emissions and costs associated with such aircraft and to determine the benefits and drawbacks of each energy system option for different market segments. Future technologies considered in the present work include laminar flow control active load alleviation new materials and structures ultra-high bypass ratio turbofan engines more efficient thermal management systems and superconducting electric motors. A multi-fidelity initial sizing framework with coupled constraint and mission analysis blocks was used for parametric airplane sizing and calculations of all necessary characteristics. Analyses performed for three reference aircraft of different sizes and ranges concluded that fuel-cell aircraft could have operating cost increases in the order of 30% compared to hydrogen combustion configurations and were caused by substantial weight and fuel burn increases. In-flight changes in emissions of fuel cell configurations at high altitudes were progressively reduced from medium-range to long-range segments from being similar to hydrogen combustion for medium-range to 24% for large long-range aircraft although fuel cell aircraft consume 22–30% more fuel than combustion aircraft. Results demonstrate a positive environmental impact of fuel cell propulsion for longrange applications the possibilities of being a more emission-universal solution if desired optimistic technology performance metrics are satisfied. The study also demonstrates progressively increasing technology requirements for larger aircraft making the long-range application’s feasibility more challenging. Therefore substantial development of fuel cell technologies for long-range aircraft is imperative. The article also emphasizes the importance of airframe and propulsion technologies and the necessity of green hydrogen production to achieve desired emissions.

Hydrogen is considered a promising solution for global decarbonisation as an alternative to fossil fuels. However it can interact with and brittle most metallic materials and is highly flammable. These properties call for a systematic investigation of physical and chemical hazards and for the definition of a comprehensive risk management and monitoring framework including proper maintenance planning. This study aims at establishing a hydrogen monitoring scheme and it provides a descriptive bibliometric and interpretative review of the current state-of-the-art of suitable techniques to ensure the safe handling of hydrogen systems. The descriptive analysis outlines the technologies available to supervise the hydrogen-material interactions and detect hydrogen leaks and flames. The bibliometric analysis shows quantitative data to identify the most relevant research groups. The interpretative study discusses the findings and examines the possibility of combining the identified techniques with maintenance programs to prevent catastrophic events.

Integrating coal-to-hydrogen production with Carbon Capture Utilization and Storage (CCUS) is essential for reducing greenhouse gas emissions and facilitating a shift towards a more sustainable energy paradigm. This paper explores the diffusion of CCUS technology within the coal-to-hydrogen sector against the dynamic backdrop of the carbon trading market. An evolutionary game-theoretic approach is utilized within a smallworld network framework to analyze the spread of CCUS technology among coal-tohydrogen enterprises. The simulation reveals that current market dynamics along with technological market and policy-related uncertainties do not robustly encourage the adoption of CCUS. As the carbon trading market continues to mature carbon prices become a significant factor influencing the diffusion of CCUS technology in coal-to-hydrogen processes. Furthermore investment costs hydrogen market prices and governmental policies are identified as pivotal elements in the propagation of CCUS technology. This study contributes valuable insights into the sustainable development of the hydrogen industry and the broader implications for low-carbon energy transition strategies.

Demand response (DR) is a crucial element in the optimization of integrated energy systems (IESs) that incor porate distributed generation (DG). However its inherent uncertainty poses significant challenges to the eco nomic viability of IESs. This research presents a novel economic dispatch model for IESs utilizing information gap decision theory (IGDT). The model integrates various components to improve IES performance and dispatch efficiency. With a focus on hydrogen energy the model considers users’ energy consumption patterns thereby improving system flexibility. By applying IGDT the model effectively addresses the uncertainty associated with DR and DG overcoming the limitations of traditional methods. The research findings indicate that in relation to the baseline method the proposed model has the potential to reduce operating costs by 6.3 % and carbon emissions by 4.2 %. The integration of a stepwise carbon trading mechanism helps boost both economic and environmental advantages achieving a 100 % wind power consumption rate in the optimized plan. In addition the daily operating costs are minimized to 23758.99 ¥ while carbon emissions are significantly reduced to 34192 kg. These findings provide quantitative decision support for IES dispatch planners to help them develop effective dispatch strategies that are consistent with low-carbon economic initiatives.

This study introduces a multi-period integrated optimization model for designing a strategic hydrogen supply chain (HSC) network concentrating on the post-production stages of conditioning storage transportation and post-conditioning. Qatar serves as the case study for evaluating three HSC pathways—ammonia (as a hydrogen carrier) liquefied hydrogen and compressed hydrogen—across pre-conditioning storage shipping and postconditioning stages. The optimization framework spans a 20-year plan supporting strategic long-term hydrogen export infrastructure planning. Economic and environmental factors are incorporated to analyze HSC performance under various scenarios accounting for realistic constraints such as investment limits and emission caps. Key findings reveal trade-offs between pathways and design strategies that must account for balancing costs with environmental impacts. Results indicate that the ammonia pathway is preferred in scenarios without emission penalties but becomes less favorable with increased penalties shifting preference toward the liquified hydrogen pathway. With stringent emission limits short- and mid-range markets are prioritized underscoring the importance of emissions-conscious strategies. This study demonstrates the utility of optimi zation tools in balancing economic and environmental objectives offering policymakers and industry stake holders a robust framework for developing sustainable and efficient HSC networks.

Solid oxide cells (SOC) play a major role in strategic visions to achieve decarbonization and climate-neutrality. With its multifuel capability this technology has received rapidly growing amount of attention from researchers worldwide. Due to the great flexibility of SOCs with respect to the fuels that can be used not only hydrogen but also biogas natural gas diesel reformates and many other conventional and alternative fuels can be used. This makes it possible to couple SOCs with diverse sustainable fuel sources to generate electricity or to generate valuable fuels such as syngas when utilizing renewable electricity. In this paper the reader is provided with a review of the existing knowledge about solid oxide fuel cell (SOFC) and solid oxide electrolysis (SOE) systems and how to safely operate them over the long-term placing a special focus on real-world operating environments. Both the utilization and generation of real commercially available fuels are taken into consideration. Different failure modes can appear during the system operation under real-world conditions and reduce the SOC lifetime an aspect that is extensively discussed in this review. Firstly a detailed discussion of the difference between carbon-free and carbon-containing fuels is presented considering different impurities and their impacts on the SOC performance stability and lifetime. Secondly unfavorable operating conditions are presented and possibilities for the early identification of different failure modes are explored. An overview of available conventional and non-conventional diagnostic tools and their applications is provided here. Overall this review paper presents a guideline for all relevant degradation issues related to SOCs operated in a real-world environment describing (i) how these issues appear and how to understand them (ii) how to predict them (iii) how to identify them and (iv) how to prevent them as well as if required how to reverse them. To achieve this goal individual chapters specifically address failure modes degradation prediction degradation prevention and performance regeneration. The reader is provided with necessary knowledge about the long-term and short-term operating stability and the degradation provoked in a compact summary. The available knowledge about specific process frequencies is summarized in one diagram which is a novel contribution of this review. This enables researchers to rapidly identify all occurring process mechanisms with SOFCs and SOECs. Moreover suggestions for how to accelerate degradation and how to regenerate performance are summarized in several tables.

Reversible solid oxide fuel cell (RSOFC) is an energy device that flexibly interchanges between electrical and chemical energy according to people’s life and production needs. The development of cell materials affects the stability and cost of the cell but also restricts its market-oriented development. After decades of research by scientists a lot of achievements and progress have been made on RSOFC materials. According to the composition and requirements of each component of RSOFC this article summarizes the research progress based on materials and discusses the merits and demerits of current cell materials in electrochemical performance. According to the efficiency of different materials in solid oxide fuel cell (SOFC mode) and solid oxide electrolyzer (SOEC mode) the challenges encountered by RSOFC in the operation are evaluated and the future development of RSOFC materials is boldly prospected.

Underground hydrogen storage (UHS) has attracted increasing attention as a promising technology for the largescale storage of renewable energy resources and the decarbonization of energy systems. This study aimed to identify critical parameters influencing UHS performance particularly the role of hydrogen conversion via in situ methanation and hydrogen recovery during production cycles. The main focus is the Lehen field in Upper Austria where a pilot hydrogen storage project was conducted under the leadership of RAG Austria AG. A layered reservoir model was developed on the basis of well-log data to simulate the field trials that occurred in 2016. A sensitivity analysis was performed with the one-parameter-at-a-time (OPAAT) method and the response surface methodology (RSM) to evaluate the impacts of different parameters on hydrogen methanation and hydrogen recovery. The RSM results indicate the activation energy as the most influential factor on methanation that accounts for ~20000 moles variation in generated methane significantly higher than the 6000 moles variance observed in OPAAT. However initial CO2 content contributes up to 15000 moles of methane gener ation as per RSM whereas OPAAT results in a larger impact of up to 32000 moles. These discrepancies demonstrate the limitations of isolated parameter analyses like OPAAT which may not accurately capture the complex interactions between factors influencing the methanation process. This research provides valuable in sights for optimizing UHS performance by emphasizing the influence of reservoir parameters on storage effi ciency. In addition a robust workflow for conducting comprehensive sensitivity analyses of UHS systems is established. By understanding these key factors the potential and predictability of large-scale UHS systems can be significantly improved.

In the pursuit of greener and more self-sufficient healthcare operations this study presents an integrated eco nomic and environmental analysis of on-site co-production of oxygen and hydrogen through proton exchange membrane electrolysis specifically designed for the Santa Maria Hospital in Lisbon Portugal. The proposed system aims to meet the hospital’s oxygen demand while simultaneously producing hydrogen for use in fuel cell electric vehicles such as ambulances. A 1.5 MW PEM electrolyser is found to be sufficient to meet the hospital’s O2 needs while generating hydrogen at a levelized cost of hydrogen of 4.6 €/kgH2. When considering the implementation costs of an on-site hydrogen refueling station an O2 drying and storage unit as well as the avoided costs in bulk liquid O2 purchases the break-even point for the sale of H2 at the refueling stations is 2.4 €/kgH2. Apart from the economic benefits that could be achieved by selling the produced H2 above this price the environmental analysis showed that 1874 tons of CO2 emissions per year could be avoided by the imple mentation of the concept proposed here. This integrated system not only contributes to the hospital’s energy independence but also serves as a model for sustainable solutions in the healthcare sector with significant environmental and financial benefits.

The team sits down with Rishi Jain to discuss Cross River’s marquee wind hydro nuclear hydrogen ammonia project in the revitalized heavy industrial Port of Belledune New Brunswick Canada.

The podcast can be found on their website.

Climate change and environmental degradation are growing concerns in today’s society which has led to greater awareness and responsibility regarding the need to adopt sustainable practices. The European Union has established the goal of achieving climate neutrality by 2050 which implies a significant reduction in greenhouse gas emissions in all sectors. To achieve this goal renewable energies the circular economy and energy efficiency are being promoted. A major source of emissions is the use of fossil fuels in different types of ships (from transport ships to those used by national navies). Among these it highlights the growing interest of the defense sector in trying to reduce these emissions. The Spanish Ministry of Defense is also involved in this effort and is taking steps to reduce the carbon footprint in military operations and improve sustainability in equipment acquisition and maintenance. The objective of this study is to identify the most promising alternative fuel among those under development for possible implementation on Spanish Navy ships in order to reduce greenhouse gas emissions and improve its capabilities. To achieve this a multi-criteria decision-making method will be used to determine the most viable fuel option. The data provided by the officers of the Spanish Navy is of great importance thanks to their long careers in front of the ships. The analysis revealed that hydrogen was the most suitable fuel with the highest priority ahead of LNG and scored the highest in most of the sections of the officials’ ratings. These fuels are less polluting and would allow a significant reduction in emissions during the navigation of ships. However a further study would also have to be carried out on the costs of adapting to their use and the safety of their use.

During the driving of a fuel cell car the expansion of the hydrogen along the emptying of the high pressure storage tank produces a cooling of the gas. The hydrogen vessel can experience a fast depressurization during acceleration or under an emergency release. This can result on the one hand in exceeding the low safety temperature limit of 40 C inside the on-board compressed hydrogen tank and on the other hand in the cooling of its walls. In the present paper defueling experiments of two different types of on-board hydrogen tanks (Type III and Type IV) have been performed in all the range of expected defueling rates. The lowest temperatures have been found on the bottom part of the Type IV tank in very fast defuelings. For average driving conditions in both types of vessels the inside gas temperature gets closer to that of the walls and the tank would arrive to the refuelling station at a temperature significantly lower than the ambient temperature.

The increasing global residential energy demand causes carbon emissions and ecological impacts necessitating cleaner efficient solutions. This study presents an innovative hybrid energy system integrating wind power and gas turbines for a four-story 16-unit residential building. The system generates electricity heating cooling and hydrogen using a Proton Exchange Membrane electrolyzer and a compression chiller. Integrating the electrolyzer enables hydrogen production and demonstrates hydrogen’s potential as a versatile clean energy carrier for systems contributing to advancements in hydrogen utilization. Simulations with Engineering Equation Solver software coupled with neural network-based multi-objective optimization fine-tuned parameters such as gas turbine efficiency wind turbine count and gas turbine inlet temperature to enhance exergy efficiency and reduce operational costs. The optimized system achieves an energy efficiency of 33.69% and an exergy efficiency of 36.95% and operates at $446.04 per hour demonstrating economic viability. It produces 51061 MWh annually exceeding the building’s energy demands and allowing surplus energy use elsewhere. BEopt simulations confirm the system meets residential needs by providing 2.52 GWh of electricity 3.36 GWh of heating and 5.11 GWh of cooling annually. This system also generates 10 kg of hydrogen per hour and achieves a CO₂ reduction of 10416 tons/year. The wind farm (25 turbines) provides most of the energy at 396.7 dollars per hour while the gas turbine operates at 80% efficiency. By addressing the challenges of intermittent renewable energy in residential Zero-Energy Buildings this research offers a scalable and environmentally friendly solution contributing to sustainable urban living and advancing hydrogen energy applications.

In this study we employ an optimization model to optimally design a self-sufficient independent of any imports and exports hydrogen infrastructure for Austria by 2030. Our approach integrates key hydrogen technologies within a detailed spatial investment and operation model – coupled with a European scale electricity market model. We focus on optimizing diverse infrastructure componentsincluding trailers pipelines electrolyzers and storages to meet Austria's projected hydrogen demand. To accurately estimate this demand in hourly resolution we combine existing hydrogen strategies and projections to account for developments in various industrial sectors consider demand driven by the transport sector and integrate hydrogen demand arising from its use in gas-powered plants. Accounting for the inherent uncertainty linked to such projections we run the analysis for two complementary scenarios. Our approach addresses the challenges of integrating large quantities of renewable hydrogen into a future energy system by recognizing the critical role of domestic production in the early market stages. The main contribution of this work is to address the gap in optimizing hydrogen infrastructure for effective integration of domestic renewable hydrogen production in Austria by 2030 considering sector coupling potentials optimal electrolyzer placement and the design of local hydrogen networks.

The emergence and design of hydrogen transport infrastructures are crucial steps towards the development of a hydrogen economy. However pipeline routing remains underdeveloped in hydrogen infrastructure design models despite its significant impact on the resultant cost and network configuration. Many previous studies assume uniform cost surfaces on which pipelines are designed. Studies that consider a variable cost surface focus on designing candidate networks rather than bespoke routes for a given infrastructure. This study proposes a novel multi-stage approach based on a graph-based Steiner tree with Obstacles Genetic Algorithm (StObGA) to route pipelines on a complex cost surface for multi-source multi-sink hydrogen networks. The application of StObGA results in cost savings of 20–40% compared to alternative graph-based methods that assume uniform cost surfaces. Furthermore this publication presents an in-depth methodological comparative analysis of different pipeline routing and sizing methods used in the literature and discusses their impact. Finally we demonstrate how this model can generate design variations and provide practical insights to inform industry and policymakers.

Energy storage is essential to address the intermittent issues of renewable energy systems thereby enhancing system stability and reliability. This paper presents the design and operation optimisation of hydrogen/battery/ hybrid energy storage systems considering component degradation and energy cost volatility. The study ex amines a real-world case study which is a grid-connected warehouse located in a tropical climate zone with a photovoltaic solar system. An accurate and robust Multi-Objective Modified Firefly Algorithm (MOMFA) is proposed for the optimal design and operation of the energy storage systems of the case study. To further demonstrate the robustness and versatility of the optimisation method another synthetic case is tested for a location in a temperate climate zone that has a high seasonal mismatch. The modelling results show that the system in the tropical zone always provides a superior return when compared to a similar system in the temperate zone due to abundant solar resources. When comparing battery-only and hydrogen-only systems battery systems perform better than hydrogen systems in many situations with a higher self-sufficient ratio and net present value. However if there is high seasonal variation and a high requirement for using renewable energy (the penetration of renewable energy is >80 %) using hydrogen for energy storage is more beneficial. Furthermore the hybrid system (i.e. combining battery and hydrogen) outperforms battery-only and hydrogenonly systems. This is attributed to the complementary combination of hydrogen which can be used as a longterm energy storage option and battery which is utilised as a short-term option. This study also shows that storing hydrogen in a long-term strategy can lower component degradation enhance efficiency and increase the total economic performance of hydrogen and hybrid storage systems. The developed optimisation method and findings of this study can support the implementation of energy storage systems for renewable energy.

The application of hydrogen energy produced by proton exchange membrane electrolyzer (PEMEC) is conducive to the solution of the greenhouse effect and the energy crisis. In order to understand the development trends and research hotspot of PEMEC in recent years a total of 1874 research articles related to this field from 2003 to 2023 were obtained from the Web of Science Core Collection (WoS CC) database. The visualization software VOSviewer is used for bibliometric analysis and the research progress hotspots and trends in the PEMEC field are summarized. It was found that in the past two decades literature in the PEMEC field has shown a trend of stable increase at first and then rapidly increasing. And it is in a stage of rapid growth after 2021.Renewable Energy previously published research articles related to PEMEC with the highest frequency of citations. There are a total of 6128 researchers in this field but core authors only account for 4.5% of the total. Although China entered this field later than the United States and Canada it has the largest number of research articles. The research results provide a comprehensive overview of various aspects in the PEMEC field which is beneficial for researchers to grasp the development hotspots of PEMEC.

Chemical looping dry reforming of methane (CLDRM) using perovskites as a catalyst is considered a promising option for producing hydrogen from biogas. In this work the life-cycle performance of a system compiling a CLDRM unit paired with a water gas shift unit a pressure swing adsorption unit and a combined cycle scheme to provide steam and electricity was assessed. The main data needed to reflect the behavior of the reforming reaction was obtained experimentally and implemented in an Aspen Plus® simulation. Inventory data was obtained through process simulation and used to assess the environmental performance of the process in terms of carbon footprint acidification freshwater eutrophication ozone depletion photochemical ozone formation and depletion of minerals and metals. Overall the environmental viability of the production of green hydrogen from biogas was found to be heavily dependent on the biogas leakage in anaerobic digestion plants. The CLDRM system was benchmarked against a conventional DRM implementation for the same feedstock. While the conventional DRM plant environmentally outperformed the perovskite-based CLDRM the latter might present advantages from an implementation point of view.

This work presents a comparative novel evaluation of two distinct fuels methanol and hydrogen production and power generation routes via fuel cells. The first route includes the methanol production from direct partial oxidation of methane to methanol where the methanol is condensed stored and sent to a direct methanol fuel cell. The second route is hydrogen production from solar methane cracking (named as turquoise hydrogen) where heat is supplied from concentrated solar power and hydrogen is stored and directed to a hydrogen fuel cell. This study aims to provide insights into these fuel's production conditions storage methods energy and exergy efficiencies. The proposed system is simulated using the Engineering Equation Solver software and a thermodynamic analysis of the entire system including all the equipment and process streams is performed. The methanol and hydrogen route's overall energy and exergy efficiencies are 39.75% 38.35% 35.84% and 34.58% respectively. The highest exergy destruction rate of 1605 kW is observed for the partial oxidation of methane to methanol. The methanol and hydrogen routes generate 32.087 MWh and 11.582 MWh of electricity for 16-hour of fuel cell operation respectively. Sensitivity analysis has been performed to observe the effects of different parameters such as operating temperature and mass flow rate of fuels on the electricity production and energy efficiencies of the systems.

In recent years production and supply of hydrogen has gained significant attention within the German energy transition. This is due to increasingly urgent pressures to mitigate climate change and geopolitical imperatives to substitute natural gas. Hydrogen is seen as an important cross-sectoral energy carrier serving multiple functions including heat production for industry and households fuel for transportation and energy storage for stabilization of electricity supply. In the context of various funding mechanisms on several administrative levels regional value chains for green hydrogen supply are emerging. To date however few studies analyzing regional hydrogen systems exist. Due to its high projected demand of energy sources for heating industrial processes and mobility Germany appears to be a very relevant research area in this emerging field. Situated within the concept of the multi-level perspective this article examines the way how regional “niches” of green hydrogen evolve and how they are organized. The study takes an evolutionary perspective in analyzing processes of embedding green hydrogen infrastructures in regional energy regimes which entered “re-configuration”-pathways. It argues that the congruence of available resources for renewable electricity established networks of institutional entrepreneurs and access to higher level funding are conditions which put incumbent regime-actors in favorable positions to implement green hydrogen niches. Conversely the embedding of green hydrogen infrastructures in regional energy systems is a case in point of how the attributes of niches in particular technological domains can be used to explain the transition pathway entered by a surrounding energy regime.

The purpose of this paper is to give a strategic overview of the existing standards governing the construction and operation of hydrogen refueling stations. A succinct and comprehensive study of hydrogen refueling station standards globally in Europe and in Italy is conducted and discussed in light of the new European Hydrogen Strategy and Roadmap. Among the numerous topics examined a particular emphasis is placed on the standards in force for on-site hydrogen production via water electrolysis hydrogen storage both liquid and gaseous and refueling protocols for lightduty and heavy-duty vehicles on an international level through the provision of ISO IEC and SAE standards; on a European level through the examination of the CEN/CENELEC database; and on an Italian national level through the analysis of the UNI database.

Hydrogen offers the UK a unique opportunity to deliver on our Net Zero ambitions enabling deep decarbonisation of the parts of the energy system that are challenging to electrify balancing the energy system by providing large scale long duration energy storage and reducing pressure on electricity infrastructure. The UK Government in recognition of the centrality of hydrogen to the future energy system has set a 10GW hydrogen production ambition to be achieved by 2030. This ambition and its supporting policies such as the Hydrogen Business Model the Low Carbon Hydrogen Standard and the Hydrogen Transport and Storage Business Models will unlock private sector investment and kick-start the UK’s hydrogen activity. Encouragingly the UK has a positive track record of deploying low carbon technologies. The  combination of the UK’s world leading policies and incentive schemes alongside a vibrant  Research Development and Innovation (RD&I)  and engineering environment has enabled rapid  deployment of technologies such as offshore wind  and electric vehicles. Yet despite being world leaders  in deployment early opportunities for regional  supply chain growth and job creation were not fully  realised and taken advantage of from inception. The  hydrogen sector is therefore at a tipping point. To  capitalise on the economic opportunity hydrogen  offers the UK must learn from prior technology  deployments and build a strong domestic hydrogen  supply chain in parallel to championing deployment.

Hydrogen is unique amongst low carbon  technologies. It represents a significant economic  opportunity with future hydrogen markets estimated  by the Hydrogen Innovation Initiative to be worth  $8tn and hydrogen technology markets estimated to reach $1tn by 20501 but crucially it is also still a nascent market. Unlike many other low carbon technologies where supply chains are already well established hydrogen supply chains are embryonic meaning that the UK has an opportunity to anchor these supply chains here and establish itself as a global leader.

The UK is well placed to capitalise on this opportunity with favourable geography and geology  that enables us to produce and store hydrogen cost effectively coupled with a strong pipeline of hydrogen projects a stable policy environment that is attractive to investors and a wealth of transferable skills and expertise from the oil and gas industry.

We must ensure that alongside our focus on deployment we are also investing in technology and supply chains. Not only will this deliver exponential economic benefits from the projects supported by Government but it will also enable us to tackle increasing global supply chain constraints. Hydrogen UK estimated in its Economic Impact Assessment that hydrogen could deliver 30000 jobs annually and £7bn of GVA by 2030

It is important to be targeted and strategic in our investment and activities and recognise that hydrogen represents a wide range of technologies and the UK should not expect to lead in every area. Hydrogen UK with the support of the Hydrogen Delivery Council has undertaken analysis of the hydrogen value chain building on UK strengths and identifying the high value items that can deliver significant impact and benefit to the UK. We have also conducted widespread engagement with project developers to identify the barriers to utilising UK technology in projects and with technology developers to identify the challenges and barriers to investing and siting development and manufacturing in the UK.

The report can be found on Hydrogen UK's website.

The current study presents a comprehensive investigation of different energy system configurations for a remote village community in India with entirely renewable electricity. Excess electricity generated by the systems has been stored using two types of energy storage options: lithium-ion batteries and green hydrogen production through the electrolysers. The hybrid renewable energy system (HRES) configurations have been sized by minimising the levelised cost of energy (LCOE). In order to identify the best-performing HRES configuration economic and environmental performance indicators has been analysed using the multi-criteria decision-making method (MCDM) TOPSIS. Among the evaluated system configurations system-1 with a photovoltaic panel (PV) size of 310.24 kW a wind turbine (WT) size of 690 kW a biogas generator (BG) size of 100 kW a battery (BAT) size of 174 kWh an electrolyser (ELEC) size of 150 kW a hydrogen tank (HT) size of 120 kg and a converter (CONV) size of 106.24 kW has been found to be the best-performing system since it provides the highest relative closeness (RC) value (∼0.817) and also has the lowest fuel consumption rate of 2.31 kg/kWh. However system-6 shows the highest amount of CO2 (143.97 kg/year) among all the studied system configurations. Furthermore a detailed technical economic and environmental analysis has been conducted on the optimal HRES configuration. The minimum net present cost (NPC) LCOE and cost of hydrogen (COH) for system 1 has been estimated to be $1960584 $0.44/kWh and $22.3/kg respectively.

In the sixth episode titled Exploring Opportunities for EU-Canada Hydrogen Cooperation our CEO Jorgo Chatzimarkakis discusses with John Risley Charmain and CEO of CFFI Ventures and Stefan Kaufmann former Innovation Commissioner for Green Hydrogen of the German government and now adviser to Thyssenkrupp. In the discussion about hydrogen market and technology's development in Canada and in Germany the businessman and the policy advisor bring two different geographical and expertise perspectives about the topic. Taking into consideration the US' IRA Canada's investments in the hydrogen sector and the European plans regarding H2Global and the Hydrogen Bank our guests compare North America and the EU. They debate over the economic and financial support the industry needs to invest in the green energy transition and the role global cooperation and competition play.

The global population is predicted to increase from ~7.3 billion to over 9 billion people by 2050.Together with rising economic growth this is forecast to result in a 50% increase in fueldemand which will have to be met while reducing carbon dioxide (CO 2 ) emissions by 50–80%to maintain social political energy and climate security. This tension between rising fuel demandand the requirement for rapid global decarbonization highlights the need to fast-track thecoordinated development and deployment of efficient cost-effective renewable technologies forthe production of CO 2 neutral energy. Currently only 20% of global energy is provided aselectricity while 80% is provided as fuel. Hydrogen (H 2) is the most advanced CO 2 -free fuel andprovides a ‘common’ energy currency as it can be produced via a range of renewabletechnologies including photovoltaic (PV) wind wave and biological systems such as microalgaeto power the next generation of H 2 fuel cells. Microalgae production systems for carbon-basedfuel (oil and ethanol) are now at the demonstration scale. This review focuses on evaluating thepotential of microalgal technologies for the commercial production of solar-driven H2 fromwater. It summarizes key global technology drivers the potential and theoretical limits ofmicroalgal H2 production systems emerging strategies to engineer next-generation systems andhow these fit into an evolving H 2 economy.

This paper presents the application of an active energy management strategy to a hybrid system consisting of a proton exchange membrane fuel cell (PEMFC) battery and supercapacitor. The purpose of energy management is to control the battery and supercapacitor states of charge (SOCs) as well as minimizing hydrogen consumption. Energy management should be applied to hybrid systems created in this way to increase efficiency and control working conditions. In this study optimization of an existing model in the literature with different meta-heuristic methods was further examined and results similar to those in the literature were obtained. Ant lion optimizer (ALO) moth-flame optimization (MFO) dragonfly algorithm (DA) sine cosine algorithm (SCA) multi-verse optimizer (MVO) particle swarm optimization (PSO) and whale optimization algorithm (WOA) meta-heuristic algorithms were applied to control the flow of power between sources. The optimization methods were compared in terms of hydrogen consumption and calculation time. Simulation studies were conducted in Matlab/Simulink R2020b (academic license). The contribution of the study is that the optimization methods of ant lion algorithm moth-flame algorithm and sine cosine algorithm were applied to this system for the first time. It was concluded that the most effective method in terms of hydrogen consumption and computational burden was the sine cosine algorithm. In addition the sine cosine algorithm provided better results than similar meta-heuristic algorithms in the literature in terms of hydrogen consumption. At the same time meta-heuristic optimization algorithms and equivalent consumption minimization strategy (ECMS) and classical proportional integral (PI) control strategy were compared as a benchmark study as done in the literature and it was concluded that meta-heuristic algorithms were more effective in terms of hydrogen consumption and computational time.

Interest in more sustainable energy sources has increased rapidly in the maritime industry and ambitious goals have been set for decreasing ship emissions. All industry stakeholders have reacted to this with different approaches including the optimisation of ship power plants the development of new energy-improving sub-systems for existing solutions or the design of entirely novel power plant concepts employing alternative fuels. This paper assesses the feasibility of different ship energy sources for an icebreaking Arctic research ship. To that end possible energy sources are assessed based on fuel infrastructure availability and operational endurance criteria in the operational area of interest. Promising alternatives are analysed further using the evidence-based Strengths Weaknesses Opportunities and Threats (SWOT) method. Then a more thorough investigation with respect to the required fuel tank space life cycle cost and CO2 emissions is implemented. The results demonstrate that marine diesel oil (MDO) is currently still the most convenient solution due to the space operational range and endurance limitations although it is possible to use liquefied natural gas (LNG) and methanol if the ship’s arrangement is radically redesigned which will also lead to reduced emissions and life cycle costs. The use of liquefied hydrogen as the only energy solution for the considered vessel was excluded from the potential options due to low volumetric energy density and high life cycle and capital costs. Even if it is used with MDO for the investigated ship the reduction in CO2 emissions will not be as significant as for LNG and methanol at a much higher capital and lifecycle cost. The advantage of the proposed approach is that unrealistic alternatives are eliminated in a systematic manner before proceeding to detailed techno-economic analysis facilitating the decision-making and investigation of various options in a more holistic manner.

The increasing political momentum advocating for decarbonization efforts has led many governments around the world to unveil national hydrogen strategies. Hydrogen is viewed as a potential enabler of deep decarbonization notably in hard-to-abate sectors such as the industry. A multi-modal hourly resolved linear programming model was developed to assess the infrastructure requirements of a low-carbon supply chain over a large region. It optimizes the deployment of infrastructure from 2025 up to 2050 by assessing four years: 2025 2030 2040 and 2050 and is location agnostic. The considered infrastructure encompasses several technologies for production transmission and storage. Model results illustrate supply chain requirements in Texas and Louisiana. Edge cases considering 100% electrolytic production were analyzed. Results show that by 2050 with an assumed industrial demand of 276 TWh/year Texas and Louisiana would require 62 GW of electrolyzers 102 GW of onshore wind and 32 GW of solar panels. The resulting levelized cost of hydrogen totaled $5.6–6.3/kgH2 in 2025 decreasing to $3.2–3.5/ kgH2 in 2050. Most of the electricity production occurs in Northwest Texas thanks to high capacity factors for both renewable technologies. Hydrogen is produced locally and transmitted through pipelines to demand centers around the Gulf Coast instead of electricity being transmitted for electrolytic production co-located with demand. Large-scale hydrogen storage is highly beneficial in the system to provide buffer between varying electrolytic hydrogen production and constant industrial demand requirements. In a system without low-cost storage liquid and compressed tanks are deployed and there is a significant renewable capacity overbuild to ensure greater electrolyzer capacity factors resulting in higher electricity curtailment. A system under carbon constraint sees the deployment of natural gas-derived hydrogen production. Lax carbon constraint target result in an important reliance on this production method due to its low cost while stricter targets enforce a great share of electrolytic production.

Over 35% of the CO2 associated with cement production comes from operational energy. The cement industry needs alternative fuels to meet its net zero emissions target. This study investigated the influence of hydrogen mixed with biofuels herein designated net zero fuel as an alternative to coal on the clinker quality and performance of cement produced in an industrial cement plant. Scanning electron microscopy X-ray diffraction and nuclear magnetic resonance were coupled to study the clinker mineralogy and polymorphs. Hydration and microstructure development in plain and slag blended cements based on the clinker were compared to commercial cement equivalent. The results revealed a lower alite/belite ratio but a significant proportion of the belite was of the α’H-C2S polymorph. These reacted faster and compensated for the alite/belite ratio. Gel and micro-capillary pores were densified which reduced total porosity and attained comparable strength to the reference plain and blended cement. This study demonstrates that the investigated net zero fuel-produced clinker meets compositional and strength requirements for plain and blended cement providing a feasible pathway for the cement industry to lower its operational carbon significantly.

The transition to hydrogen as a clean energy source is critical for addressing climate change and supporting environmental sustainability. This review provides an accessible summary of general research trends in hydrogen risk assessment methodologies enabling diverse stakeholders including researchers policymakers and industry professionals to gain insights into this field. By examining representative studies across theoretical experimental and simulation-based approaches the review highlights prominent trends and applications within academia and industry. The key focus is on evaluating risks in stationary and transportation applications paying particular attention to hydrogen storage systems transportation infrastructures and energy systems. By offering a concise yet informative summary of hydrogen risk assessment trends this paper aims to serve as a foundational resource for fostering safer and more sustainable hydrogen systems.

This bibliometric study examines the evolution of compressed-hydrogen storage technologies over the last 20 years revealing exponential growth in research and highlighting key advancements in compressed-hydrogen storage materials-based solutions and integration with renewable energy systems. The analysis highlights the pivotal role of composite material tanks and the filament-winding process in revolutionizing storage technology. These innovations have enhanced safety reduced weight and facilitated adaptation for use in automotive and industrial applications. Global research efforts are characterized by substantial international collaboration spearheaded by a small cohort of highly productive researchers and supported by a broader network of contributors. Notwithstanding the ongoing challenges pertaining to safety considerations and cost scalability the potential of hydrogen as a clean energy carrier and its role in balancing renewable energy systems serve to reinforce its importance in the transition to sustainable energy.

Steel production is a highly energy-intensive industry responsible for significant greenhouse gas emissions. Electrification of this sector is challenging making green hydrogen technology a promising alternative. This research performs a thermodynamic analysis of green hydrogen production for steel manufacturing using the direct reduction method. Four solid oxide electrolyzer (SOE) modules replace the traditional reformer to produce 2.88 kg/s of hydrogen gas serving as a reducing agent for iron pellets to yield 30 kg/s of molten steel. These modules are powered by 37801 photovoltaic units. Additionally a thermal storage system utilizing 1342 tons of steel slag stores waste heat from Electric Arc Furnace (EAF) exhaust gases. This stored energy preheats iron scraps charged into the EAF reducing energy consumption by 5%. A life cycle assessment conducted using open LCA software reveals that the global warming potential (GWP) for the entire process with a capacity of 30 kg/s equates to 93 kg of CO2. The study also assesses other environmental impacts such as acidification potential ozone formation fine particle formation and human toxicity. Results indicate that the EAF significantly contributes to global warming and fine particle formation while the direct reduction process notably impacts ozone formation and acidification potential.

Faced with a global consensus on net-zero emissions the use of clean fuels to entirely or substantially replace traditional fuels has emerged as the industry’s primary development direction. Alcohol–hydrogen fuels primarily based on methanol are a renewable and sustainable energy source. This research focuses on energy sustainability and presents a boiler fuel blending system that uses methanol–hydrogen combinations. This system uses the boiler’s waste heat to catalytically decompose methanol into a gas mostly consisting of H2 and CO which is then co-combusted with the original fuel to improve thermal efficiency and lower emissions. A comparative experimental study considering natural gas (NG) blending with hydrogen and dissociated methanol gas (DMG) was carried out in a small natural gas boiler. The results indicate that with a controlled mixed fuel flow of 10 m3/h and an excess air coefficient of 1.2 a 10% hydrogen blending ratio maximizes the boiler’s thermal efficiency (ηt) resulting in a 3.5% increase. This ratio also results in a 1% increase in NOx emissions a 25% decrease in HC emissions and a 5.66% improvement in the equivalent economics (es). Meanwhile blending DMG at 15% increases the boiler’s ηt by 3% reduces NOx emissions by 13.8% and HC emissions by 20% and improves the es by 8.63%. DMG as a partial substitute for natural gas outperforms hydrogen in various aspects. If this technology can be successfully applied and promoted it could pave a new path for the sustainable development of energy in the boiler sector.

Underground Hydrogen Storage (UHS) as an emerging large-scale energy storage technology has shown great promise to ensure energy security with minimized carbon emission. A set of comprehensive UHS site evaluation criteria based on important factors that affect UHS performances is needed for its potential commercialization. This study focuses on the UHS site evaluation of gas mixing. The economic implications of gas mixing between injected hydrogen gas and the residual or cushion gas in a porous storage reservoir is an emerging problem for Underground Hydrogen Storage (UHS). It is already clear that reservoir scale heterogeneity such as formation structure (e.g. formation dip angle) and facies heterogeneity of the sedimentary rock may considerably affect the reservoir-scale mechanical dispersion-induced gas mixing during UHS in high permeability braided-fluvial systems (a common depleted reservoir type for UHS). Following this finding the current study uses the processmimicking modeling software to build synthetic meandering-fluvial reservoir models. Channel dimensions and the presence of abandoned channel facies are set as testing parameters resulting in 4 simulation cases with 200 realizations. Numerical flow simulations are performed on these models to investigate and compare the effects of reservoir and metre-scale heterogeneity on UHS gas mixing. Through simulation channel dimensions (reservoir-scale heterogeneity) are found to affect the uncertainty of produced gas composition due to mixing (represented by the P10-P90 difference of hydrogen fraction in a produced stream) by up to 42%. The presence of abandoned channel facies (metre-scale heterogeneity) depending on their architectural relationship with meander belts could also influence the gas mixing process to a comparable extent (up to 40%). Moreover we show that there is no clear statistical correlation between gas mixing and typical reservoir characterization parameters such as original gas in place (OGIP) average reservoir permeability and the Dykstra-Parsons coefficient. Instead the average time of travel of all reservoir cells calculated from flow diagnostics shows a negative correlation with the level of gas mixing. These results reveal the importance of 3D reservoir architecture analysis (integration of multiple levels of heterogeneity) to UHS site evaluation on gas mixing in depleted gas reservoirs. This study herein provides valuable insights into UHS site evaluation regarding gas mixing.

Source-load output uncertainty poses significant risks to the stable operation of Integrated Energy Systems (IESs). To ensure safe and stable system operation while optimizing the balance among robustness economic viability and low-carbon emissions this paper presents a two-stage robust optimal scheduling model for IESs. This model is supported by hydrogen-containing electric dual-energy conversion characteristics under source-load uncer tainty. Additionally to promote the low-carbon characteristics of the system a ladder carbon trading mechanism is introduced on the source side of the carbon source equipment. Furthermore the integration of hydrogen energy enhances the clean characteristics of source-side multi-energy coupling. The proposed utilization mode Power-to-Hydrogen Hydrogen-to-Power Hydrogen Energy Storage and Hydrogen Load (P2H-H2P-HES-HL) allows for bidirectional conversion thereby increasing the flexibility and responsiveness of overall system scheduling. Finally to ensure that the model closely reflects actual operational and scheduling conditions a twophase robust approach is employed to address source-load uncertainties. This approach is solved iteratively using the linear transformation of the Karush-Kuhn-Tucker (KKT) conditions and the Column-and-Constraint Gener ation (C&CG) algorithm. The results demonstrate that the proposed model significantly enhances the scheduling capability of the system in coping with uncertainty thereby effectively ensuring its flexibility and security

A thermodynamic assessment using Gibbs free energy minimization to explore the potential of winery wastewater steam reforming (WWWSR) as a technique to treat water while simultaneously producing renewable hydrogen was conducted for the first time. This assessment focused on four types of reactors: a conventional reactor (CR) a sorption-enhanced reactor (SER) with CO2 capture a membrane reactor (MR) with H2 removal and a sorption-enhanced membrane reactor (SEMR) that combines features of both the SER and MR. The effects on WWWSR of temperature pressure water content in the feed composition of winery wastewater (WWW) sorbent to feed ratio (SFR) and the split fraction of H2 in the membrane were studied. For the CR SER MR and SEMR the study showed that low pressures and high water content in the reactor inlet resulted in higher hydrogen production. Considering a representative WWW composition with a water content of 75 wt% in the feed it was shown that the CR needed to operate at extremely high temperatures (over 600 ◦C) to maximize H2 yield while producing less hydrogen than its counterparts. In contrast the MR and SER achieved higher hydrogen production at optimal temperatures around 500 ◦C while the SEMR performed even better producing more hydrogen at just 400 ◦C. Moreover the organic composition of the feed stream did not significantly influence the optimal temperature and pressure conditions for maximizing hydrogen production. However wastewater with a higher fraction of sugars generated more hydrogen whereas wastewater with a higher fraction of acetic acid produced less hydrogen via the steam reforming reaction. Notably a novel energy analysis was conducted demonstrating that the energy self-sufficiency of this process changed drastically when different reactor types were considered. Only the MR with a high degree of hydrogen separation in the membrane the SER with optimal quantities of CO2-capturing sorbent and the SEMR can be energetically selfsufficient as they produce enough hydrogen to offset the energy expenditure associated with steam reforming

The renewable hydrogen economy is recognized as an integral solution for decarbonizing energy sectors. However high costs have hindered widespread deployment. One promising way of reducing the costs is optimization. Optimization generally involves finding the configuration of the renewable generation and hydrogen system components that maximizes return on investment. Previous studies have included many aspects into their optimisations including technical parameters and different costs/socio-economic objective functions however there is no clear best-practice framework for model development. To address these gaps this critical review examines the latest development in renewable hydrogen microgrid models and summarises the best modeling practice. The findings show that advances in machine learning integration are improving solar electricity generation forecasting hydrogen system simulations and load profile development particularly in data-scarce regions. Additionally it is important to account for electrolyzer and fuel cell dynamics rather than utilizing fixed performance values. This review also demonstrates that typical meteorological year datasets are better for modeling solar irradiation than first-principle calculations. The practicability of socio-economic objective functions is also assessed proposing that the more comprehensive Levelized Value Addition (LVA) is best suited for inclusion into models. Best practices for creating load profiles in regions like the Global South are discussed along with an evaluation of AI-based and traditional optimization methods and software tools. Finally a new evidence-based multi-criteria decision-making framework integrated with machine learning insights is proposed to guide decision-makers in selecting optimal solutions based on multiple attributes offering a more comprehensive and adaptive approach to renewable hydrogen system optimization.

Hydrogen is a crucial energy carrier for the Clean Energy Sustainable Development Goals and the just transition to low/zero-carbon energy. As a top CO2-emitting country hydrogen (especially green hydrogen) production in South Africa has gained momentum due to the availability of resources such as solar energy land wind energy platinum group metals (as catalysts for electrolysers) and water. However the demand for green hydrogen in South Africa is insignificant which implies that the majority of the production must be exported. Despite the positive developments there are unclear matters such as dependence on the national electricity grid for green hydrogen production and the cost of transporting it to Asian and European markets. Hence this study aims to explore opportunities for economic expansion for sustainable production transportation storage and utilisation of green hydrogen produced in South Africa. This paper uses a thematic literature review methodology. The key findings are that the available renewable energy sources incentivizing the green economy carbon taxation and increasing the demand for green hydrogen in South Africa and Africa could decrease the cost of hydrogen from 3.54 to 1.40 €/kgH2 and thus stimulate its production usage and export. The appeal of green hydrogen lies in diversifying products to green hydrogen as an energy carrier clean electricity synthetic fuels green ammonia and methanol green fertilizers and green steel production with the principal purpose of significant energy decarbonisation and economic and foreign earnings. These findings are expected to drive the African hydrogen revolution in agreement with the AU 2063 agenda.

A lot of countries have recently published updated hydrogen strategies with many of them increasing and renewing their commitment. In parallel corresponding policy mechanisms are increasingly coming into focus with the first ones already having awarded funding contracts to projects and construction being underway. However these policies are usually translated from renewable energy policy without considering the specific risks and uncertainties spillovers and positive externality of operating grid-conducive electrolyzers in electricity grids which are increasingly subjected to electricity supply volatility from renewables. This article details how different aspects of a dedicated hydrogen policy can address the technology’s specific issues from an economic perspective namely funding provision market and technology risk mitigation and the complex relationship with further actors in electricity markets. Results show that compared to renewable energy policy mechanisms need to emphasize the input side more strongly as price risks and intermittency from electricity markets are more prominent than from hydrogen markets. Also it proposes a targeted mechanism to capture the positive externality of mitigating excess electricity in the grid while keeping investment security high. Economic policy should consider such approaches before scaling support and avoiding the design shortcomings experienced with early RE policy.

This paper focuses on the critical role of long-duration energy storage (LDES) technologies in facilitating renewable energy integration and achieving carbon neutrality. It presents a systematic review of four primary categories: mechanical energy storage chemical energy storage electrochemical energy storage and thermal energy storage. The study begins by analyzing the technical advantages and geographical constraints of pumped hydro energy storage (PHES) and compressed air energy storage (CAES) in high-capacity applications. It then explores the potential of hydrogen and synthetic fuels for long-duration clean energy storage. The section on electrochemical energy storage highlights the high energy density and flexible scalability of lithium-ion batteries and redox flow batteries. Finally the paper evaluates innovative advancements in large-scale thermal energy storage technologies including sensible heat storage latent heat storage and thermochemical heat storage. By comparing the performance metrics application scenarios and development prospects of various energy storage technologies this work provides theoretical support and practical insights for maximizing renewable energy utilization and driving the sustainable transformation of global energy systems.

Ammonia is a versatile energy carrier without carbon emissions that can be used for power generation. In this article a techno-economic analysis has been done to predict the levelized cost of electricity production using gas turbines with clean fuel in Iran. In the technical discussion the analysis of different scenarios of ammonia and hydrogen fuel composition ratio was done and by keeping the turbine inlet temperature to the same gas turbine as the SGT5-2000E turbine the output power in different fuel ratios is around 192.8 to 229.0 MW was variable and reached the maximum value in some proportions. Also in the economic discussion the effects of fuel cost and interest rate parameters were investigated sensitivity analysis was performed on different combined ratios of ammonia and hydrogen in fuel and an economic analysis of the ideal ratio was conducted. The price of ammonia fuel was calculated from 222 $/ton to 2000 $/ton and the levelized cost of electricity production changed from 91.7 $/MWh to 673.4 $/MWh. Additionally an economic comparison was made between the utilization of ammonia-hydrogen and natural gas fuels. This alternative fuel can be a promising way to produce power without carbon emissions and suitable storage for renewables.

This paper presents a thorough initial evaluation of hydrogen gaseous storage and pipeline infrastructure emphasizing health and safety protocols as well as capacity considerations pertinent to industrial applications. As hydrogen increasingly establishes itself as a vital energy vector within the transition towards low-carbon energy systems the formulation of effective storage and transportation solutions becomes imperative. The investigation delves into the applications and technologies associated with hydrogen storage specifically concentrating on compressed hydrogen gas storage elucidating the principles underlying hydrogen compression and the diverse categories of hydrogen storage tanks including pressure vessels specifically designed for gaseous hydrogen containment. Critical factors concerning hydrogen gas pipelines are scrutinized accompanied by a review of appropriate compression apparatus types of compressors and particular pipeline specifications necessary for the transport of both hydrogen and oxygen generated by electrolysers. The significance of health and safety in hydrogen systems is underscored due to the flammable nature and high diffusivity of hydrogen. This paper defines the recommended health and safety protocols for hydrogen storage and pipeline operations alongside exemplary practices for the effective implementation of these protocols across various storage and pipeline configurations. Moreover it investigates the function of oxygen transport pipelines and the applications of oxygen produced from electrolysers considering the interconnected safety standards governing hydrogen and oxygen infrastructure. The conclusions drawn from this study facilitate the advancement of secure and efficient hydrogen storage and pipeline systems thereby furthering the overarching aim of scalable hydrogen energy deployment within both energy and industrial sectors.

We investigate the challenges and options for repurposing existing natural gas pipelines for hydrogen transportation. Challenges of re-purposing are mainly related to safety and due to the risk of hydrogen embrittlement of pipeline steels and the smaller molecular size of the gas. From an economic perspective the lower volumetric energy density of hydrogen compared to natural gas is a challenge. We investigate three pipeline repurposing options in depth: a) no modification to the pipeline but enhanced maintenance b) use of gaseous inhibitors and c) the pipe-in-pipe approach. The levelized costs of transportation of these options are compared for the case of the German Norddeutsche Erdgasleitung (NEL) pipeline. We find a similar cost range for all three options. This indicates that other criteria such as the sunk costs public acceptance and consumer requirements are likely to shape the decision making for gas pipeline repurposing.

The future of energy is of global concern with hydrogen emerging as a potential solution for sustainable energy development. This paper provides a comprehensive analysis of the current hydrogen energy landscape its potential role in a decarbonized future and the hurdles that need to be overcome for its wider implementation. The first elucidates the opportunities hydrogen energy presents including its potential for decarbonizing various sectors in addition addresses the challenges that stand in the way of hydrogen energy large-scale adoption. The obtained results provide a comprehensive overview of the hydrogen energy horizon emphasizing the need to balance opportunities and challenges for its successful integration into the global energy landscape. It highlights the importance of continued research development and collaboration across sectors to realize the full potential of hydrogen as a sustainable and low-carbon energy carrier.

Proton exchange membrane electrolyzer cell (PEMEC) will play a central role in future power-to-H2 plants. Current research focuses on the materials and operation parameters. Setting up experiments to explore operational accident scenarios about safety feasibility is not always practical. This paper focuses on building mathematical and prediction models of hydrogen and oxygen mixing scenarios of PEMEC. A mathematical model of the PEMEC device was customized in the Aspen Custom Model (ACM) software and integrated various critical Physico-chemical phenomena as the original data set for the prediction model. The results of the mathematical simulation verified the experimental results. The prediction model proposes an artificial neural network (ANN) framework to predict component distribution in the gas stream to prevent hydrogen-oxygen explosion scenarios. The presented approach by training ANN to 1000 sets of hydrogen-oxygen mixing simulation data from ACM is applicable to bypass tedious and non-smooth systems of equations for PEMEC.

This paper reports on the experimental data analysis and numerical results carried out by algorithms in order to meet the provisions of Industry 4.0 in the field of research of Solid Oxide Fuel Cell/Electrolyzer. A performance mapping of the analyzed SOFC/SOE systems is developed in order to enhance system efficiency when it is fed by biofuels. The analyses concern the main operative parameters such as pressure temperature fuel compositions and other main system parameters such as fuel and oxidant utilization factors and the recirculation of anode exhaust stream gas.