Publications

Energy transition is a key driver to combat climate change and achieve zero carbon future. Sustainable and costeffective hydrogen production will provide valuable addition to the renewable energy mix and help minimize greenhouse gas emissions. This study investigates the performance of in-situ hydrogen production (IHP) process using a full-field compositional model as a precursor to experimental validation The reservoir model was simulated as one geological unit with a single point uniform porosity value of 0.13 and a five-point connection type between cell to minimize computational cost. Twenty-one hydrogen forming reactions were modelled based on the reservoir fluid composition selected for this study. The thermodynamic and kinetic parameters for the reactions were obtained from published experiments due to the absence of experimental data specific to the reservoir. A total of fifty-four simulation runs were conducted using CMG STARS software for 5478 days and cumulative hydrogen produced for each run was recorded. Results generated were then used to build a proxy model using Box-Behnken design of experiment method and Support Vector Machine with RBF kernel. To ascertain accuracy of the proxy models analysis of variance (ANOVA) was conducted on the variables. The average absolute percentage error between the proxy model and numerical simulation was calculated to be 10.82%. Optimization of the proxy model was performed using genetic algorithm to maximize cumulative hydrogen produced. Based on this optimized model the influence of porosity permeability well location injection rate and injection pressure were studied. Key results from this study reveals that lower permeability and porosity reservoirs supports more hydrogen yield injection pressure had a negligible effect on hydrogen yield and increase in oxygen injection rate corelated strongly with hydrogen production until a threshold value beyond which hydrogen yield decreased. The framework developed in the study could be used as tool to assess candidate reservoirs for in-situ hydrogen production.

This article summarizes current research on the life cycle assessment (LCA) of fuel cell electric vehicles (FCEVs) in road transport. Increasing greenhouse gas emissions and climate change are pushing the transport sector to intensify efforts toward decarbonization. One promising solution is the adoption of hydrogen technologies whose development is supported by European Union regulations such as the “Fit for 55” package. FCEVs are characterized by zero emissions during operation but their environmental impact largely depends on the methods of hydrogen production. The use of renewable energy sources in hydrogen production can significantly reduce greenhouse gas emissions while hydrogen produced from fossil fuels can even result in higher emissions compared to internal combustion engine vehicles. This article also discusses the importance of hydrogen refueling infrastructure and the efficiency of fuel storage and transportation systems. In conclusion LCA shows that FCEVs can support the achievement of climate goals provided that the development of hydrogen production technologies based on renewable sources and the corresponding infrastructure is ensured. The authors also highlight the potential of hybrid technologies as a transitional solution in the process of transforming the transport sector.

Hydrogen has emerged as a key element in the transition to a sustainable energy model. Among hydrogen storage and transport technologies liquid organic hydrogen carriers (LOHCs) stand out as a promising alternative for large-scale long-term use. Catalysts essential in these systems are usually composed of platinum group metals (PGMs) over alumina known for their high cost and scarcity. This study analyzes the overall environmental impact of the LOHC benzyltoluene/perhydro-benzyltoluene-based hydrogen supply chain by means of the life cycle assessment (LCA) focusing on the synthesis processes of novel low-PGM catalysts which remain under explored in existing literature. The results identify dehydrogenation as the most impactful step due to significant heat consumption and highlight the substantial environmental footprint associated with the use of platinum in catalyst production. This research provides crucial insights into the environmental implications of LOHC systems particularly the role of novel low-PGM catalysts and offers guidance for their future large-scale applications.

Clean hydrogen is touted as a cornerstone of the global energy transition. It can help to decarbonize hard-to-electrify sectors ship renewable power over great distances and boost energy security. Clean hydrogen’s appeal is increasingly felt in the Global South where countries seek to benefit from production export and consumption opportunities new infrastructures and technological innovations. These geographies are however in the process of taking shape and their associated power configurations spatialities and socio-ecological consequences are yet to be more thoroughly understood and examined. Drawing on political geography perspectives this article proposes the concept of “hydrogen landscape” – or in short H2-scape – to theorize and explore hydrogen transitions as space-making processes imbued with power relations institutional orders and social meanings. In this endeavor it outlines a conceptual framework for understanding the making of H2-scapes and offers three concrete directions for advancing empirical research on hydrogen transitions in the Global South: (1) H2-scapes as resource frontiers; (2) H2-scapes as port-centered arrangements; and (3) H2-scapes as failure. As hydrogen booms in finances projects and visibility the article illuminates conceptual tools and perspectives to think about and facilitate further research on the emergent political geographies of hydrogen transitions particularly in more uneven unequal and vulnerable Global South landscapes.

Low temperature water electrolysers such as Proton Exchange Membrane Water Electrolysers (PEMWEs) Alkaline Water Electrolysers (AWEs) and Anion Exchange Membrane Water Electrolysers (AEMWEs) are known to be sensitive to water quality with a range of common impurities impacting performance hydrogen quality and device lifetime. Purification of feed water adds to cost operational complexity and design limitations while failure of purification equipment can lead to degradation of electrolyser materials and components. Increased robustness to impurities will offer a route to longer device lifetimes and reduced operating costs but understanding of the impact of impurities and associated degradation mechanisms is currently limited. This critical review offers for the first time a comprehensive overview of relevant impurities in operating electrolysers and their impact. Impurity sources degradation mechanisms characterisation techniques water purification technologies and mitigation strategies are identified and discussed. The review generalises already reported mechanisms proposes new mechanisms and provides a framework for consideration of operational implications.

Ammonia production currently contributesalmost 11% of global industrial carbon dioxide emissions or1.3% of global emissions. In the context of global emissiontargets and growing demand decarbonization of this processis highly desirable. We present a method to calculate a firstestimate for the optimum size of an ammonia productionplant (at the process level) the required renewable energy(RE) supply and the levelized cost of ammonia (LCOA) forislanded operation with a hydrogen buffer. A model wasdeveloped to quantitatively identify the key variables thatimpact the LCOA (relative to a ±10 GBP/tonne change inLCOA): levelized cost of electricity (±0.89 GBP/MWh) electrolyzer capital expenditure (±65 GBP/kW) minimum Haber−Bosch (HB) load (±12% of rated power) maximum rate of HB load ramping and RE supply mix. Using 2025/2030 estimatesresults in a LCOA of 588 GBP/tonne for Lerwick Scotland. The application of the model will facilitate and improve theproduction of carbon-free ammonia in the future.

Hydrogen is a carbon-neutral fuel so in theory it holds enormous potential. The use of hydrogen as a fuel for traditional internal combustion engines is becoming increasingly prominent. The authors now have the opportunity to retrofit a single-cylinder diesel research engine to an engine with hydrogen operation. For this reason before that conversion they prepared a comprehensive review study regarding hydrogen. Firstly the study analyzes the most essential properties of hydrogen in terms of mixture formation and combustion compared to diesel. After that it deals with indirect and direct injection and what kind of combustion processes can occur. Since there is a possibility of preignition backfire and knocking the process can be dangerous in the case of indirect mixture formation and so a short subsection is devoted to these uncontrolled combustion phenomena. The next subsection shows how important in many ways a special spark plug and ignition system are for hydrogen operation. The next part of the study provides a detailed presentation of the possible combustion chamber design for operation with hydrogen fuel. The last section reveals how many parameters can be focused on analyzing the hydrogen’s combustion process. The authors conclude that intake manifold injection and a Heron-like combustion chamber design with a special spark plug with an ignition system would be an appropriate solution.

The decarbonization of hard-to-abate industries is crucial for keeping global warming to below 2◦C. Green or renewable hydrogen synthesized through water electrolysis has emerged as a sustainable alternative for fossil fuels in energy-intensive sectors such as aluminum cement chemicals steel and transportation. However the scalability of green hydrogen production faces challenges including infrastructure gaps energy losses excessive power consumption and high costs throughout the value chain. Therefore this study analyzes the challenges within the green hydrogen value chain focusing on the development of nascent technologies. Presenting a comprehensive synthesis of contemporary knowledge this study assesses the potential impacts of green hydrogen on hard-to-abate sectors emphasizing the expansion of clean energy infrastructure. Through an exploration of emerging renewable hydrogen technologies the study investigates aspects such as economic feasibility sustainability assessments and the achievement of carbon neutrality. Additionally considerations extend to the potential for large-scale renewable electricity storage and the realization of net-zero goals. The findings of this study suggest that emerging technologies have the potential to significantly increase green hydrogen production offering affordable solutions for decarbonization. The study affirms that global-scale green hydrogen production could satisfy up to 24% of global energy needs by 2050 resulting in the abatement of 60 gigatons of greenhouse gas (GHG) emissions - equivalent to 6% of total cumulative CO2 emission reductions. To comprehensively evaluate the impact of the hydrogen economy on ecosystem decarbonization this article analyzes the feasibility of three business models that emphasize choices for green hydrogen production and delivery. Finally the study proposes potential directions for future research on hydrogen valleys aiming to foster interconnected hydrogen ecosystems.

Metal hydride-based hydrogen storage (MHHS) has been used for several purposes including mobile and stationary applications. In general the overall MHHS performance for both applications depends on three main factors which are the appropriate selection of metal hydride material uses design configurations of the MHHS based on the heat exchanger and overall operating conditions. However there are different specific requirements for the two applications. The weight of the overall MHHS is the key requirement for mobile applications while hydrogen storage capacity is the key requirement for stationary applications. Based on these requirements several techniques have been recently used to enhance MHHS performance by mostly considering the faster hydrogen absorption/desorption reaction. Considering metal hydride (MH) materials their low thermal conductivity significantly impacts the hydrogen absorption/desorption reaction. For this purpose a comprehensive understanding of these three main factors and the hydrogen absorption/desorption reaction is critical and it should be up to date to obtain the suitable MHHS performance for all related applications. Therefore this article reviews the key techniques which have recently been applied for the enhancement of MHHS performance. In the review it is demonstrated that the design and layout of the heat exchanger greatly affect the performance of the internal heat exchanger. The initial temperature of the heat transfer fluid and hydrogen supply pressure are the main parameters to increase the hydrogen sorption rate and specific heating power. The higher supply pressure results in the improvement in specific heating power. For the metal hydride material selection under the consideration of mobile applications and stationary applications it is important to strike trade-offs between hydrogen storage capacity weight material cost and effective thermal conductivity.

Climate change necessitates the development of sustainable energy systems with hydrogen technologies playing a key role in this transition. Additive manufacturing (AM) offers a significant potential to enhance the efficiency of hydrogen energy components and reduce their costs through rapid prototyping design freedom and functional integration. This review provides the first comprehensive summary of the current state of research on the application of AM processes in the production storage and utilization of hydrogen. It highlights various AM processes such as powder bed fusion directed energy deposition fused filament fabrication and stereolithography for the advancement of hydrogen energy components. Current research trends include the material development multi-material AM hybrid processes and the integration of artificial intelligence and machine learning. At present the technologies presented are mainly at a development stage of TRL 4–5. The next major step towards industrialization is the demonstration of prototypes outside the laboratory.