Iraq
Optimum Blending Hydrogen Ratio in Spray Combustion to Reduce Emissions of Nitrogen Oxides
Sep 2025
Publication
This study examined the effects of adding hydrogen to flammable liquid fuel droplets on emissions. It was found that an optimal mixing ratio with hydrogen can reduce the amount of NO in the reaction zone which is the area where the primary combustion reactions occur. N-pentane is burnt in air enriched with different amounts of hydrogen and the effects of the amount of hydrogen in the air on the combustion and emission parameters are investigated numerically. The combustion is modelled with the PDF/mixture fraction and standard twoequation turbulence models and thermal NO models are used for this modelling. The determination of the optimum H2 blending ratio is evaluated after the estimation results. It is evident that the addition of H2 led to an increase in spray flame temperatures. As a result the addition of H2 increases the combustion performance of n-pentane. The emissions evaluation results show that a blending ratio of 20% H2 reduces CO emissions at the combustion’s reaction zone and also results in a decrease in the mixture fraction. There is an increase in NO emissions due to the increase in spray flame temperatures. Combustion under air conditions containing 20% H2 by volume resulted in the highest temperature levels reaching 2130 K while the reduced NO levels decreased to approximately 11.3%. The thermal NO model when combined with the combustion model provides a sufficient level of agreement with the experimental data.
Comparative Analysis of Solar Cells and Hydrogen Fuels: A Mini Review
Jul 2024
Publication
The aim of this mini-review is to compare the effectiveness and potential of solar cells and hydrogen fuel technologies in clean energy generation. Key aspects such as efficiency scalability environmental footprint and technological maturity are examined. Solar cells are analyzed for their ability to convert sunlight into electricity efficiently and their potential for widespread deployment with minimal environmental impact. Hydrogen fuel technologies are assessed based on their efficiency in hydrogen production scalability and overall environmental footprint from production to end use. The review identifies significant challenges including high costs infrastructure needs and policy requirements as well as opportunities for innovation and market growth. The findings provide insights to guide decision-making towards a sustainable energy future.
Review on Ammonia as a Potential Fuel: From Synthesis to Economics
Feb 2021
Publication
Ammonia a molecule that is gaining more interest as a fueling vector has been considered as a candidate to power transport produce energy and support heating applications for decades. However the particular characteristics of the molecule always made it a chemical with low if any benefit once compared to conventional fossil fuels. Still the current need to decarbonize our economy makes the search of new methods crucial to use chemicals such as ammonia that can be produced and employed without incurring in the emission of carbon oxides. Therefore current efforts in this field are leading scientists industries and governments to seriously invest efforts in the development of holistic solutions capable of making ammonia a viable fuel for the transition toward a clean future. On that basis this review has approached the subject gathering inputs from scientists actively working on the topic. The review starts from the importance of ammonia as an energy vector moving through all of the steps in the production distribution utilization safety legal considerations and economic aspects of the use of such a molecule to support the future energy mix. Fundamentals of combustion and practical cases for the recovery of energy of ammonia are also addressed thus providing a complete view of what potentially could become a vector of crucial importance to the mitigation of carbon emissions. Different from other works this review seeks to provide a holistic perspective of ammonia as a chemical that presents benefits and constraints for storing energy from sustainable sources. State-of-the-art knowledge provided by academics actively engaged with the topic at various fronts also enables a clear vision of the progress in each of the branches of ammonia as an energy carrier. Further the fundamental boundaries of the use of the molecule are expanded to real technical issues for all potential technologies capable of using it for energy purposes legal barriers that will be faced to achieve its deployment safety and environmental considerations that impose a critical aspect for acceptance and wellbeing and economic implications for the use of ammonia across all aspects approached for the production and implementation of this chemical as a fueling source. Herein this work sets the principles research practicalities and future views of a transition toward a future where ammonia will be a major energy player.
Hydrogen Energy Systems: Technologies, Trends, and Future Prospects
May 2024
Publication
This review critically examines hydrogen energy systems highlighting their capacity to transform the global energy framework and mitigate climate change. Hydrogen showcases a high energy density of 120 MJ/kg providing a robust alternative to fossil fuels. Adoption at scale could decrease global CO2 emissions by up to 830 million tonnes annually. Despite its potential the expansion of hydrogen technology is curtailed by the inefficiency of current electrolysis methods and high production costs. Presently electrolysis efficiencies range between 60 % and 80 % with hydrogen production costs around $5 per kilogram. Strategic advancements are necessary to reduce these costs below $2 per kilogram and push efficiencies above 80 %. Additionally hydrogen storage poses its own challenges requiring conditions of up to 700 bar or temperatures below −253 °C. These storage conditions necessitate the development of advanced materials and infrastructure improvements. The findings of this study emphasize the need for comprehensive strategic planning and interdisciplinary efforts to maximize hydrogen's role as a sustainable energy source. Enhancing the economic viability and market integration of hydrogen will depend critically on overcoming these technological and infrastructural challenges supported by robust regulatory frameworks. This comprehensive approach will ensure that hydrogen energy can significantly contribute to a sustainable and low-carbon future.
Assessment of Wettability and Rock-fluid Interfacial Tension of Caprock: Implications for Hydrogen and Carbon Dioxide Geo-storage
Mar 2022
Publication
Underground hydrogen (H2) storage (UHS) and carbon dioxide (CO2) geo-storage (CGS) are prominent methods of meeting global energy needs and enabling a low-carbon global economy. The pore-scale distribution reservoir-scale storage capacity and containment security of H2 and CO2 are significantly influenced by interfacial properties including the equilibrium contact angle (θE) and solid-liquid and solid-gas interfacial tensions (γSL and γSG). However due to the technical constraints of experimentally determining these parameters they are often calculated based on advancing and receding contact angle values. There is a scarcity of θE γSL and γSG data particularly related to the hydrogen structural sealing potential of caprock which is unavailable in the literature. Young's equation and Neumann's equation of state were combined in this study to theoretically compute these three parameters (θE γSL and γSG) at reservoir conditions for the H2 and CO2 geo-storage potential. Pure mica organic-aged mica and alumina nano-aged mica substrates were investigated to explore the conditions for rock wetting phenomena and the sealing potential of caprock. The results reveal that θE increases while γSG decreases with increasing pressure organic acid concentration and alkyl chain length. However γSG decreases with increasing temperatures for H2 gas and vice versa for CO2. In addition θE and γSL decrease whereas γSG increases with increasing alumina nanofluid concentration from 0.05 to 0.25 wt%. Conversely θE and γSL increase whereas γSG decreases with increasing alumina nanofluid concentration from 0.25 to 0.75 wt%. The hydrogen wettability of mica (a proxy of caprock) was generally less than the CO2 wettability of mica at similar physio-thermal conditions. The interfacial data reported in this study are crucial for predicting caprock wettability alterations and the resulting structural sealing capacity for UHS and CGS.
Transitioning to Sustainable Economic Resilience through Renewable Energy and Green Hydrogen: The Case of Iraq
Sep 2024
Publication
The study investigates the potential of transitioning Iraq a nation significantly dependent on fossil fuels toward a green hydrogen-based energy system as a pathway to achieving sustainable economic resilience. As of 2022 Iraqi energy supply is over 90% reliant on hydrocarbons which also account for 95% of the country foreign exchange earnings. The global energy landscape is rapidly shifting towards cleaner alternatives and the volatility of oil prices has made it imperative for the country to diversify its energy sources. Green hydrogen produced through water electrolysis powered by renewable energy sources such as solar and wind offers a promising alternative given country vast renewable energy potential. The analysis indicates that with strategic investments in green hydrogen infrastructure the country could reduce its hydrocarbon dependency by 30% by the year 2030. This transition could not only address pressing environmental challenges but also contribute to the economic stability of the country. However the shift to green hydrogen is not without significant challenges including water scarcity technological limitations and the necessity for a robust regulatory framework. The findings underscore the importance of international partnerships and supportive policies in facilitating this energy transition. Adopting renewable energy and green hydrogen technologies the country has the potential to become a leader in sustainable energy within the region. This shift would not only drive economic growth and energy security but also contribute to global efforts towards environmental sustainability positioning country favorably in a future low-carbon economy.
The Influence of Gas Fuel Enrichment with Hydrogen on the Combustion Characteristics of Combustors: A Review
Oct 2024
Publication
Hydrogen is a promising fuel because it has good capabilities to operate gas turbines. Due to its ignition speed which exceeds the ignition of traditional fuel it achieves a higher thermal efficiency while the resulting emissions are low. So it was used as a clean and sustainable energy source. This paper reviews the most important research that was concerned with studying the characteristics of hydrogen combustion within incinerators and power generation equipment where hydrogen was used as a fuel mixed with traditional fuel in the combustion chambers of gas turbines. It also includes an evaluation of the combustion processes and flame formation resulting from the enrichment of gaseous fuels with hydrogen and partial oxidation. A large amount of theoretical and experimental work in this field has been reviewed. This review summarizes the predictive and experimental results of various research interests in the field of hydrogen combustion and also production.
A Review of Green Hydrogen Production Based on Solar Energy; Techniques and Methods
Feb 2023
Publication
The study examines the methods for producing hydrogen using solar energy as a catalyst. The two commonly recognised categories of processes are direct and indirect. Due to the indirect processes low efficiency excessive heat dissipation and dearth of readily available heat-resistant materials they are ranked lower than the direct procedures despite the direct procedures superior thermal performance. Electrolysis bio photosynthesis and thermoelectric photodegradation are a few examples of indirect approaches. It appears that indirect approaches have certain advantages. The heterogeneous photocatalytic process minimises the quantity of emissions released into the environment; thermochemical reactions stand out for having low energy requirements due to the high temperatures generated; and electrolysis is efficient while having very little pollution created. Electrolysis has the highest exergy and energy efficiency when compared to other methods of creating hydrogen according to the evaluation.
Towards Decarbonizing Gas: A Generic Optimal Gas Flow Model with Linepack Constraints for Assessing the Feasibility of Hydrogen Blending in Existing Gas Networks
Aug 2025
Publication
Hydrogen blending into natural gas networks is a promising pathway to decarbonize the gas sector but requires bespoke fluid-dynamic models to accurately capture the properties of hydrogen and assess its feasibility. This paper introduces a generalizable optimal transient gas flow model for transporting homogeneous natural gashydrogen mixtures in large-scale networks. Designed for preliminary planning the model assesses whether a network can operate under a given hydrogen blending ratio without violating existing constraints such as pressure limits pipeline and compressor capacity. A distinguishing feature of the model is a multi-day linepack management strategy that engenders realistic linepack profiles by precluding mathematically feasible but operationally unrealistic solutions thereby accurately reflecting the flexibility of the gas system. The model is demonstrated on Western Australia’s 7560 km transmission network using real system topology and demand data from several representative days in 2022. Findings reveal that the system can accommodate up to 20 % mol hydrogen potentially decarbonizing 7.80 % of gas demand.
Exploring the Potential of Ammonia as a Fuel: Advances in Combustion Understanding and Large-scale Furnace Applications
Sep 2025
Publication
From an environmental standpoint carbon-free energy carriers such as ammonia and hydrogen are essential for future energy systems. However their hightemperature chemical behavior remains insufficiently understood posing challenges for the development and optimization of advanced combustion technologies. Ammonia in particular is globally available and cost-effective especially for energy-intensive industries. The addition of ammonia or hydrogen to methane significantly reduces the accuracy of existing predictive models. Therefore validated and detailed data are urgently needed to enable reliable design and performance predictions. This review highlights the compatibility of ammonia with existing combustion infrastructure facilitating a smoother transition to more sustainable heating methods without the need for entirely new systems. Applications in high-temperature heating processes such as metal processing ceramics and glass production and power generation are of particular interest. This review focuses on the systematic assessment of alternative fuel mixtures comprising ammonia and hydrogen as well as natural gas with particular consideration of existing safety-related parameters and combustion characteristics. Fundamental quantities such as the laminar burning velocity are discussed in the context of their relevance for fuel mixtures and their scalability toward turbulent flame propagation which is of critical importance for industrial burner and reactor design. The influence of fuel composition on ignition limits is examined as these are essential parameters for safety margin definitions and operational boundary conditions. Furthermore flame stability in mixed-fuel systems is addressed to evaluate the practical feasibility and robustness of combustion under varying process conditions. A detailed overview of current diagnostic and analysis methods follows encompassing both pollutant measurement techniques and the detection of key radical species. These diagnostics form the experimental basis for reaction kinetics modeling and mechanism validation. Given the importance of emission formation in combustion systems a dedicated subsection summarizes major emission trends even though a comprehensive treatment would exceed the scope of this review. Thermal radiation effects which are highly relevant for heat transfer and system efficiency in large-scale applications are then reviewed. In parallel current developments in numerical simulation approaches for industrial-scale combustion systems are presented including aspects of model accuracy boundary conditions and computational efficiency. The review also incorporates insights from materials engineering particularly regarding high-temperature material performance corrosion resistance and compatibility with combustion products. Based on these interdisciplinary findings operational strategies for high-temperature furnaces are outlined and selected industrial reference systems are briefly presented. This integrated approach aims to support the design optimization and safe operation of next-generation combustion technologies utilizing carbon-free or low-carbon fuels.
Harnessing Wind for Hydrogen: Comparative MCDM-GIS Assessment of Optimal Plant Locations
Jul 2025
Publication
This research aimed to perform an in-depth comparative analysis of MCDM methods utilizing ArcGIS Pro 3.0.2 to identify the most suitable sites for wind-powered hydrogen production plants in Erbil Governorate Iraq. VIKOR TOPSIS SAW and Weighted Overlay techniques were implemented and applied to evaluate various criteria. A comparative analysis determined that VIKOR had the highest consistency and robustness making it the most suitable approach for selecting a site for windpowered hydrogen facilities. Spatial analysis showed that the southern and southwestern regions of Erbil Governorate were the most favourable areas for hydrogen generation. Wind turbine technical feasibility assessments identified the E112/4500 and V126e3.45 turbine models as the most efficient for these regions with high annual hydrogen production. The spatial configuration including the optimal turbine spacing had a significant effect on the capacity and production potential. ArcPro integration with MCDM significantly enhanced spatial analysis providing high-resolution data processing and advanced visualization capabilities.
Flexible Economic Energy Management Including Environmental Indices in Heat and Electrical Microgrids Considering Heat Pump with Renewable and Storage Systems
Oct 2025
Publication
This study discusses energy management in thermal and electrical microgrids while taking heat pumps renewable sources thermal and hydrogen storages into account. The weighted total of the operating cost grid emissions level voltage and temperature deviation function and other factors makes up the objective function of the suggested method. The restrictions include the operationflexibility model of resources and storages micro-grid flexibility limits and optimum power flow equations. Point Estimation Method is used in this work to simulate load energy price and renewable phenomenon uncertainty. A fuzzy decision-making methodology is used to arrive at a compromise solution that satisfies network operators’ operational environmental and financial goals. The innovations of this paper include energy management of various smart microgrids simultaneous modeling of several indicators especially flexibility investigation of optimal performance of resources and storage devices and modeling of uncertainty considering low computational time and an accurate flexibility model. Numerical findings indicate that the fuzzy decision-making approach has the capability to reach a compromise point in which the objective functions approach their minimum values. The integration of the proposed uncertainty modeling with precise flexibility modeling results in a reduction in computational time when compared to stochastic optimization based on scenarios. For the compromise point and uncertainty modeling with PEM by efficiently managing resources and thermal and hydrogen storages scheme is capable of attaining high flexibility conditions. Compared to load flow studies the approach can enhance the operational environmental and economic conditions of smart microgrids by approximately 33–57% 68% and 33–68% respectively under these circumstances.
Integrated Renewable Energy Supply Architecture for Advancing Hydrogen Symbiosis and Eco Synergistic Smart Grid Interactions with Next Generation Combustion Technologies
Jul 2025
Publication
This study introduces the Smart Grid Hybrid Electrolysis-and-Combustion System (SGHE-CS) designed to seamlessly integrate hydrogen production storage and utilization within smart grid operations to maximize renewable energy use and maintain grid stability. The system achieves a hydrogen production efficiency of 98.5% indicating the effective conversion rate of electrical energy to hydrogen via PEM electrolysis. Combustion efficiency reaches 98.1% reflecting the proportion of hydrogen energy successfully converted into usable power through advanced staged combustion. Storage and transportation efficiency is 96.3% accounting for energy losses during hydrogen compression storage and delivery. Renewable integration efficiency is 97.3% representing the system’s capacity to utilize variable renewable energy inputs without curtailment. Operational versatility is 99.3% denoting the system’s ability to maintain high performance across load demands and grid conditions. Real-time monitoring and adaptive control strategies ensure reliability and resilience positioning SGHE-CS as a promising solution for sustainable low-carbon energy infrastructure.
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