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Hydrogen Diffusion and Its Effect on Hydrogen Embrittlement in DP Steels with Different Martensite Content
Dec 2020
Publication
The hydrogen diffusion behavior and hydrogen embrittlement susceptibility of dual phase (DP) steels with different martensite content were investigated using the slow strain-rate tensile test and hydrogen permeation measurement. Results showed that a logarithmic relationship was established between the hydrogen embrittlement index (IHE) and the effective hydrogen diffusion coefficient (Deff). When the martensite content is low ferrite/ martensite interface behaves as the main trap that captures the hydrogen atoms. Also when the Deff decreases IHE increases with increasing martensite content. However when the martensite content reaches approximately 68.3% the martensite grains start to form a continuous network Deff reaches a plateau and IHE continues to increase. This is mainly related to the reduction of carbon content in martensite and the length of ferrite/martensite interface which promotes the diffusion of hydrogen atoms in martensite and the aggregation of hydrogen atoms at the ferrite/martensite interface. Finally a model describing the mechanism of microstructure-driven hydrogen diffusion with different martensite distribution was established.
The Role of the Argon and Helium Bath Gases on the Detonation Structure of H2/)2 Mixture
Sep 2021
Publication
Recent modeling efforts of non-equilibrium effects in detonations have suggested that hydrogen-based detonations may be affected by vibrational non-equilibrium of the hydrogen and oxygen molecules effects which could explain discrepancies of cell sizes measured experimentally and calculated without relaxation effects. The present study addresses the role of vibrational relaxation in 2H2/O2 detonations by considering two-bath gases argon and helium. These two gases have the same thermodynamic and kinetic effects when relaxation is neglected. However due to the bath gases differences in molecular weight and reduced mass differences which affect the molecular collisions relaxation rates can be changed by approximately 50-70%. Experiments were performed in a narrow channel in mixtures of 2H2/O2/7Ar and 2H2/O2/7He to evaluate the role of the bath gas on detonation cellular structures. The experiments showed differences in velocity deficits and cell sizes for experimental conditions keeping the induction zone length constant in each of the mixtures. These differences were negligible in sensitive mixtures but increased with the increase in velocity deficits while the cell sizes approaching the channel dimensions. Near the limits differences of cell size in two mixtures approached a factor of 2. These differences were however reconciled by accounting for the viscous losses to the tube walls evaluated using a modified version of Mirels' laminar boundary layer theory and generalized Chapman-Jouguet theory for eigenvalue detonations. The experiments suggest that there is an influence of relaxation effects on the cellular structure of detonations which is more sensitive to wall boundary conditions. However the previous works showed that the impact of vibrational non-equilibrium in a mixture of H2/Air is more visible due to the effects of N2 in the air slowest to relax. Previous discrepancies suggested to be indicative of relaxation effects should be reevaluated by the inclusion of wall loss effects.
Assessment of Hydrogen Flame Length Full Bore Pipeline Rupture
Sep 2021
Publication
The study aims at the development of a safety engineering methodology for the assessment of flame length after full-bore rupture of hydrogen pipeline. The methodology is validated using experimental data on hydrogen jet flame from full-bore pipeline rupture by Acton et al. (2010). The experimental pressure dynamics in the hydrogen pipeline system is simulated using previously developed adiabatic and “isothermal” blowdown models. The hydrogen release area is taken as equal similar to the experiment to doubled pipeline cross-section as hydrogen was coming out from both sides of the ruptured pipe. The agreement with the experimental pressure decay in the piping system was achieved using discharge coefficient CD=0.26 and CD=0.21 for adiabatic and “isothermal” blowdown model respectively that indicates significant friction and minor pressure losses. The hydrogen flame length was calculated using the dimensionless correlation by Molkov and Saffers (2013). The correlation relies on the density of hydrogen in the choked flow at the pipe exit. The maximum experimental flame length between 92 m and 111 m was recorded at 6 s after the pipe rupture under the ground. The calculated by the dimensionless correlation flame length is 110 m and 120 m for the “isothermal” and adiabatic blowdown model respectively. This is an acceptable accuracy for such a large-scale experiment. It is concluded that the methodology can be applied as an engineering tool to assess flame length resulting from ruptured hydrogen pipelines.
Improved Engine Performance and Significantly Reduced Greenhouse Gas Emissions by Fumigating Hydrogen in a Diesel Engine
Oct 2022
Publication
A thermodynamic model was developed for combustion performance and emissions with a reference diesel fuel a 10 vol% methanol blend with 90 vol% diesel a 10 vol% ethanol with 90 vol% diesel and a 4% hydrogen fumigating in the inlet port along with diesel direct injection. The diesel and two alcohol blends (10% methanol–90% diesel and 10% ethanol–90% diesel) was directly injected into the cylinder while hydrogen was fumigated at the inlet port. The model was developed by commercial GT-Suite software. Besides engine performance exergy and energy rates were estimated for the four fuels. Among the four fuels/fuel blends hydrogen fuel (4% fumigated hydrogen) shows the best performance in terms of exergy energy rates specific fuel consumption power and greenhouse gas emissions. Regarding greenhouse gases carbon dioxide was only considered in this investigation as it contributes to a significant detrimental effect on environmental pollution.
Centralized and Decentralized Electrolysis-based Hydrogen Supply Systems for Road Transportation - A Modeling Study of Current and Future Costs
Oct 2022
Publication
This work compares the costs of three electrolysis-based hydrogen supply systems for heavy road transportation: a decentralized off-grid system for hydrogen production from wind and solar power (Dec-Sa); a decentralized system connected to the electricity grid (Dec-Gc); and a centralized grid-connected electrolyzer with hydrogen transported to refueling stations (Cen-Gc). A cost-minimizing optimization model was developed in which the hydrogen production is designed to meet the demand at refueling stations at the lowest total cost for two timeframes: one with current electricity prices and one with estimated future prices. The results show that: For most of the studied geographical regions Dec-Gc gives the lowest costs of hydrogen delivery (2.2e3.3V/kgH2) while Dec-Sa entails higher hydrogen production costs (2.5e6.7V/kgH2). In addition the centralized system (Cen-Gc) involves lower costs for production and storage than the grid-connected decentralized system (Dec-Gc) although the additional costs for hydrogen transport increase the total cost (3.5e4.8V/kgH2).
Techno-economic Viability of Islanded Green Ammonia as a Carbon-free Energy Vector and as a Substitute for Conventional Production
Jul 2020
Publication
Decarbonising ammonia production is an environmental imperative given that it independently accounts for 1.8% of global carbon dioxide emissions and supports the feeding of over 48% of the global population. The recent decline of production costs and its potential as an energy vector warrant investigation of whether green ammonia production is commercially competitive. Considering 534 locations in 70 countries and designing and operating the islanded production process to minimise the levelised cost of ammonia (LCOA) at each we show the range of achievable LCOA the cost of process flexibility the components of LCOA and therein the scope of LCOA reduction achievable at present and in 2030. These results are benchmarked against ammonia spot prices cost per GJ of refined fuels and the LCOE of alternative energy storage methods. Currently a LCOA of $473 t1 is achievable at the best locations the required process flexibility increases the achievable LCOA by 56%; the electrolyser CAPEX and operation are the most significant costs. By 2030 $310 t1 is predicted to be achievable with multiple locations below $350 t1 . At $25.4 GJ11 ) that do not have the benefit of being carbon-free.
Impact of Polymers on Magnesium-Based Hydrogen Storage Systems
Jun 2022
Publication
In the present scenario much importance has been provided to hydrogen energy systems (HES) in the energy sector because of their clean and green behavior during utilization. The developments of novel techniques and materials have focused on overcoming the practical difficulties in the HES (production storage and utilization). Comparatively considerable attention needs to be provided in the hydrogen storage systems (HSS) because of physical-based storage (compressed gas cold/cryo compressed and liquid) issues such as low gravimetric/volumetric density storage conditions/parameters and safety. In material-based HSS a high amount of hydrogen can be effectively stored in materials via physical or chemical bonds. In different hydride materials Mg-based hydrides (Mg–H) showed considerable benefits such as low density hydrogen uptake and reversibility. However the inferior sorption kinetics and severe oxidation/contamination at exposure to air limit its benefits. There are numerous kinds of efforts like the inclusion of catalysts that have been made for Mg–H to alter the thermodynamic-related issues. Still those efforts do not overcome the oxidation/contamination-related issues. The developments of Mg–H encapsulated by gas-selective polymers can effectively and positively influence hydrogen sorption kinetics and prevent the Mg–H from contaminating (air and moisture). In this review the impact of different polymers (carboxymethyl cellulose polystyrene polyimide polypyrrole polyvinylpyrrolidone polyvinylidene fluoride polymethylpentene and poly(methyl methacrylate)) with Mg–H systems has been systematically reviewed. In polymer-encapsulated Mg–H the polymers act as a barrier for the reaction between Mg–H and O2/H2O selectively allowing the H2 gas and preventing the aggregation of hydride nanoparticles. Thus the H2 uptake amount and sorption kinetics improved considerably in Mg–H.
Next Steps for the Gas Grid- Future Gas Series Part 1
Sep 2014
Publication
Policy Connect Carbon Connect and sector and Parliamentary experts have collaborated to present options for the gas grid to play a useful role in the UK’s transition to a low carbon energy system through the widespread use of low carbon gas. The report calls on Government to support the transition to a more flexible gas grid that uses various forms of gas including low carbon gases such as hydrogen and biomethane.
Hydrogen–Natural Gas Blending in Distribution Systems—An Energy, Economic, and Environmental Assessment
Aug 2022
Publication
Taking into account the international policies in the field of environmental protection in the world in general and in the European Union in particular the reduction of greenhouse gas (GHG) emissions and primarily of carbon dioxide has become one of the most important objectives. This can be obtained through various renewable energy sources and non-polluting technologies such as the mixing of hydrogen and natural gas. Combining hydrogen with natural gas is an emerging trend in the energy industry and represents one of the most important changes in the efforts to achieve extensive decarbonisation. The importance of this article consists of carrying out a techno-economic study based on the simulation of annual consumptions regarding the construction and use of production capacities for hydrogen to be used in mixtures with natural gas in various percentages in the distribution network of an important operator in Romania. In order to obtain relevant results natural gas was treated as a mixture of real gases with a known composition as defined in the chromatographic bulletin. The survey presents a case study for the injection of 5% 10% and 20% hydrogen in the natural gas distribution system of Bucharest the largest city in Romania. In addition to conducting this techno-economic study the implications for final consumers of this technical solution in reducing greenhouse gas emissions—mainly those of carbon dioxide from combustion—are also presented.
Going Global: An Update on Hydrogen Valleys and their Role in the New Hydrogen Economy
Sep 2022
Publication
Hydrogen is a key cornerstone of the green transformation of the global economy and a major lever to diversify energy supplies and accelerate the clean energy transition. Hydrogen will be essential to replace natural gas coal and oil in hard-to-decarbonise sectors in industry mobility and energy. Hydrogen Valleys will become an important cornerstone in producing importing transporting and using clean hydrogen in Europe.
A Techno-economic Analysis of Ammonia-fuelled Powertrain Systems for Rail Freight
Apr 2023
Publication
All diesel-only trains in the UK will be removed from services by 2040. High volumetric density rapid refuelling ability and sophisticated experience in infrastructure and logistics make ammonia a perfect hydrogen carrying fuel for rail freight which urgently requires an economically viable solution. This study conducted a novel techno-economic study of ammonia-fuelled fuel cell powertrains to be compared with current diesel engine-based system and emerging direct hydrogen-fuelled fuel cell system. The results demonstrate that hydrogen-fuelled Proton Exchange Membrane Fuel Cells (PEMFCs) and ammonia-fuelled PEMFCs (using an ammonia cracker) are more cost-effective in terms of Levelized Cost of Electricity. The ammonia fuel storage requires 61.5-75 % less space compared to the hydrogen storage. Although the ammonia-fuelled Solid Oxide Fuel Cells (SOFCs) powertrain has the highest electricity generation efficiency (56%) the overall cost requires a major reduction by 70% before it could be considered as an economically viable solution.
Effect of TPRD Diameter and Direction of Release on Hydrogen Dispersion in Underground Parking
Sep 2021
Publication
Unignited hydrogen release in underground parking could be considered inherently safer if the safety strategy to avoid the formation of the flammable hydrogen-air mixture under a ceiling is followed. This strategy excludes destructive deflagrative combustion and associated pressure and thermal effects in the case of ignition. This paper aims at understanding the effects of the thermally activated pressure relieve device (TPRD) diameter and direction of release on the build-up of hydrogen flammable concentration under the ceiling in the presence of mechanical ventilation required for underground parking. The study employs the similarity law for hydrogen jet concentration decay in a free under-expanded jet to find the lower limit of TPRD diameter that excludes the formation of a flammable mixture under the ceiling during upward release. This approach is conservative and does not include the effect of mechanical ventilation providing flow velocity around a few meters per second which is significantly below velocities in hydrogen momentum-dominated under-expanded jets. Hydrogen releases downwards under a vehicle at different angles and with different air velocities due to mechanical ventilation were investigated using computational fluid dynamics (CFD). The joint effect of TPRD diameter release direction and mechanical ventilation is studied. TPRD diameters for the release of hydrogen upwards and downwards preventing the creation of flammable hydrogen-air mixture under the parking ceiling are defined for different ceiling heights and locations of TPRD above the floor. Recommendations to the design of TPRD devices to underpin the safe introduction of hydrogen fuelled vehicles in currently existing underground parking and infrastructure are formulated."
Beyond Traditional Energy Sector Coupling: Conserving and Efficient Use of Local Resources
Jun 2022
Publication
Decentralisation and sector coupling are becoming increasingly crucial for the decarbonisation of the energy system. Resources such as waste and water have high energy recovery potential and are required as inputs for various conversion technologies; however waste and water have not yet been considered in sector coupling approaches but only in separate examinations. In this work an open-source sector coupling optimisation model considering all of these resources and their utilisation is developed and applied in a test-bed in an Israeli city. Our investigations include an impact assessment of energy recovery and resource utilisation in the transition to a hydrogen economy with regard to the inclusion of greywater and consideration of emissions. Additionally sensitivity analyses are performed in order to assess the complexity level of energy recovery. The results demonstrate that waste and water energy recovery can provide high contributions to energy generation. Furthermore greywater use can be vital to cover the water demands in scarcity periods thus saving potable water and enabling the use of technology. Regarding the transition to hydrogen technologies resource energy recovery and management have an even higher effect than in the original setup. However without appropriate resource management a reduction in emissions cannot be achieved. Furthermore the sensitivity analyses indicate the existence of complex relationships between energy recovery technologies and other energy system operations.
Optimized Configuration of Diesel Engine-Fuel Cell-Battery Hybrid Power Systems in a Platform Supply Vessel to Reduce CO2 Emissions
Mar 2022
Publication
The main objective of this paper is to select the optimal configuration of a ship’s power system considering the use of fuel cells and batteries that would achieve the lowest CO2 emissions also taking into consideration the number of battery cycles. The ship analyzed in this work is a Platform Supply Vessel (PSV) used to support oil and gas offshore platforms transporting goods equipment and personnel. The proposed scheme considers the ship’s retrofitting. The ship’s original main generators are maintained and the fuel cell and batteries are installed as complementary sources. Moreover a sensitivity analysis is pursued on the ship’s demand curve. The simulations used to calculate the CO2 emissions for each of the new hybrid configurations were developed using HOMER software. The proposed solutions are auxiliary generators three types of batteries and a protonexchange membrane fuel cell (PEMFC) with different sizes of hydrogen tanks. The PEMFC and batteries were sized as containerized solutions and the sizing of the auxiliary engines was based on previous works. Each configuration consists of a combination of these solutions. The selection of the best configuration is one contribution of this paper. The new configurations are classified according to the reduction of CO2 emitted in comparison to the original system. For different demand levels the results indicate that the configuration classification may vary. Another valuable contribution of this work is the sizing of the battery and hydrogen storage systems. They were installed in 20 ft containers since the installation of batteries fuel cells and hydrogen tanks in containers is widely used for ship retrofit. As a result the most significant reduction of CO2 emissions is 10.69%. This is achieved when the configuration includes main generators auxiliary generators a 3119 kW lithium nickel manganese cobalt (LNMC) battery a 250 kW PEMFC and 581 kg of stored hydrogen.
Comparative Risk Assessment of a Hydrogen Refueling Station Using Gaseous Hydrogen and Formic Acid as the Hydrogen Carrier
Mar 2023
Publication
To realize a hydrogen economy many studies are being conducted regarding the development and analysis of hydrogen carriers. Recently formic acid has been receiving attention as a potential hydrogen carrier due to its high volumetric energy density and relatively safe characteristics. However hydrogen refueling systems using formic acid are very different from conventional hydrogen refueling stations and quantitative risks assessments need to be conducted to verify their safe usage. In this study a comparative safety analysis of a formic acid hydrogen refueling station (FAHRS) and a gaseous hydrogen refueling station (GHRS) was conducted. Since there is no FAHRS under operation a process simulation model was developed and integrated with quantitative risk assessment techniques to perform safety analysis. Results of the analysis show that the FAHRS poses less risk than the GHRS where the vapor cloud explosion occurring in the buffer tank is of greatest consequence. A GHRS poses a greater risk than an FAHRS due to the high pressure required to store hydrogen in the tube trailer. The mild operating conditions required for storage and dehydrogenation of formic acid contribute to the low risk values of an FAHRS. For risk scenarios exceeding the risk limit risk mitigation measures were applied to design a safe process for GHRS. The results show that the installation of active safety systems for the GHRS allow the system to operate within acceptable safety regions.
Pore-scale Study of Microbial Hydrogen Consumption and Wettability Alteration During Underground Hydrogen Storage
Feb 2023
Publication
Hydrogen can be a renewable energy carrier and is suggested to store renewable energy and mitigate carbon dioxide emissions. Subsurface storage of hydrogen in salt caverns deep saline formations and depleted oil/gas reservoirs would help to overcome imbalances between supply and demand of renewable energy. Hydrogen however is one of the most important electron donors for many subsurface microbial processes including methanogenesis sulfate reduction and acetogenesis. These processes cause hydrogen loss and changes of reservoir properties during geological hydrogen storage operations. Here we report the results of a typical halophilic sulfate-reducing bacterium growing in a microfluidic pore network saturated with hydrogen gas at 35 bar and 37°C. Test duration is 9 days. We observed a significant loss of H2 from microbial consumption after 2 days following injection into a microfluidic device. The consumption rate decreased over time as the microbial activity declined in the pore network. The consumption rate is influenced profoundly by the surface area of H2 bubbles and microbial activity. Microbial growth in the silicon pore network was observed to change the surface wettability from a water-wet to a neutral-wet state. Due to the coupling effect of H2 consumption by microbes and wettability alteration the number of disconnected H2 bubbles in the pore network increased sharply over time. These results may have significant implications for hydrogen recovery and gas injectivity. First pore-scale experimental results reveal the impacts of subsurface microbial growth on H2 in storage which are useful to estimate rapidly the risk of microbial growth during subsurface H2 storage. Second microvisual experiments provide critical observations of bubble-liquid interfacial area and reaction rate that are essential to the modeling that is needed to make long-term predictions. Third results help us to improve the selection criteria for future storage sites.
Roadmap to Achieving Sustainable Development via Green Hydrogen
Jan 2023
Publication
The conversion to renewable energy can be achieved when cities and communities start to depend on sustainable resources capable of providing for the basic needs of the community along with a reduction in the daily problems and issues that people face. These issues such as poverty hunger sanitation and economic difficulties are highlighted in the Sustainable Development Goals (SDGs) which aim to limit and eradicate these problems along with other environmental obstacles including climate change and Greenhouse Gases (GHGs). These SDGs containing 17 goals target each sector and provide propositions to solve such devastating problems. Hydrogen contributes to the targets of these sustainable developments since through its implementation in different industries the levels of GHG will drop and thus contribute to the climate change which Earth is facing. Further through the usage of such resources many job opportunities will also be developed thus enhancing the economy and lifting the status of society. This paper classifies the four different types of hydrogen and outlines the differences between them. The paper then emphasizes the importance of green hydrogen use within the shipping industry transportation and infrastructure along with economic and social development through job opportunities. Furthermore this paper provides case studies tackling green hydrogen status in the United Kingdom United States of America and European Union as well as Africa United Arab of Emirates and Asia. Finally challenges and recommendations concerning the green hydrogen industry are addressed. This paper aims to relate the use of green hydrogen to the direct and indirect goals of SDG.
Adapting Maintenance Facilities for Hydrogen
Sep 2021
Publication
Transit planners and managers need to be armed with the best information on how to make the transition towards zero emission transit fleets. Although zero emission transit is becoming increasingly necessary many transit operators are unsure of how to make the transition and how to replace their existing infrastructure especially when it comes to on site bus maintenance facilities. Upgrading vehicle maintenance facilities to safely accommodate hydrogen can be a deciding factor in whether an operator chooses to adopt this fuel for its fleet. This paper reviews best practices in hydrogen bus maintenance facilities for transit agencies. It includes safety and infrastructure factors transit managers must consider when transitioning to servicing and maintaining fuel cell electric buses. Although local requirements and regulations vary this paper will help the reader gain insights on what needs to be considered in transitioning a workshop. As with any fuel hydrogen must be treated with respect and care. Today’s hydrogen fuel cell technologies are mature in their safety features. Fuel cell electric buses are designed and built for safety and the protocols for safe storage maintenance and refuelling are well developed and understood.
The Role of Hydrogen in the Corrosion and Cracking of Steels - A Review
Oct 2021
Publication
In many processes of steel industrial including steel manufacture storage and service hydrogen could be absorbed into metallic materials and the absorbed hydrogen seriously impaired its corrosion resistance. This paper provides a comprehensive review on the effects of hydrogen on passive film anodic dissolution pitting corrosion and stress corrosion cracking and based on the review the mechanism by which hydrogen promotes corrosion of steel and subsequently leads to cracking has been discussed. It is envisaged that hydrogen harms the stability of the passive film and as a result escalates anode’s activation of steel eventually leading to pitting and stress corrosion cracking.
Development of a Hydrogen Valley for Exploitation of Green Hydrogen in Central Italy
Oct 2022
Publication
Green hydrogen exploitation plays a crucial role in achieving carbon neutrality by 2050. Hydrogen in fact provides a number of key benefits for the energy system due to its integrability with other clean technologies for energy production and consumption. This paper is aimed at presenting the project of recovery of an abandoned industrial area located in central Italy by developing a site for the production of green hydrogen. To this aim the analysis of the territorial and industrial context of the area allowed us to design the project phases and to define the sizing criteria of the hydrogen production plant. The results of a preliminary cost–benefit analysis show that a huge initial investment is required and that in the short term the project is sustainable only with a very large public grant. On the other hand in the long term the project is sustainable and the benefits significantly overcome the costs.
Roadmap Towards Zero Emissions, BEVs and FCEVs
Oct 2021
Publication
A “combined world” of fuel cell electric vehicles (FCEVs) and battery electric vehicles (BEVs) will create a greener transportation sector faster and cheaper than one of the solutions alone. Hydrogen Council with analytical support from McKinsey and Company published a report that highlights the complementary roles of FCEVs and BEVs in a decarbonised transportation sector.
The analysis found that each solution has comparable systemic efficiencies and similar CO2 life cycle intensity. From the vehicle user perspective FCEVs and BEVs will provide the flexibility and convenience to meet their specific context of use and geographic location. Additionally the costs of two supporting infrastructure for FCEVs and BEVs is cheaper than one infrastructure network primarily due to the reduced peak loads and avoidance of costly upgrades on the electricity grid. The report’s messages were developed in dialogue with the Observatory Group which consisted of representatives of government agencies and academia as well as associations and companies active in sectors like regenerative electricity generation electricity grid equipment manufacturing electric vehicle charging fleet management.
The paper can be found on their website.
The analysis found that each solution has comparable systemic efficiencies and similar CO2 life cycle intensity. From the vehicle user perspective FCEVs and BEVs will provide the flexibility and convenience to meet their specific context of use and geographic location. Additionally the costs of two supporting infrastructure for FCEVs and BEVs is cheaper than one infrastructure network primarily due to the reduced peak loads and avoidance of costly upgrades on the electricity grid. The report’s messages were developed in dialogue with the Observatory Group which consisted of representatives of government agencies and academia as well as associations and companies active in sectors like regenerative electricity generation electricity grid equipment manufacturing electric vehicle charging fleet management.
The paper can be found on their website.
ASSET Study on Geolocation of Hydrogen Production in the EU
Oct 2021
Publication
The modelling underpinning the scenarios for the EU long-term strategy did not include hydrogen trade. The assumption was that each Member State (MS) supplies its own needs for hydrogen and synthetic fuels. The goal of this study is to develop a model to undertake optimal geolocation of hydrogen production between MS including the possibility to trade hydrogen and therefore use the RES potential more optimally and decrease energy system costs at EU level. Specifically the new model helps to identify the geo-location of: 1. Renewable energy production (PV wind biomass hydro) 2. Location of RES and hydrogen production facilities 3. Storage infrastructure also for natural gas and storage technologies i.e. batteries pumping etc. 4. Infrastructure by road and pipeline
Everything About Hydrogen Podcast: Hydrogen Review of 2022
Oct 2022
Publication
In order to wrap Season 3 of EAH appropriately we are honored to have our most popular EAH guest back with us Alicia Eastman President and Co-Founder of Intercontinental Energy is here to help us review the big hydrogen happenings of 2022 and preview some of the most important predictions and expectations for the sector coming for 2023.
The podcast can be found on their website.
The podcast can be found on their website.
Modelling and Evaluation of PEM Hydrogen Technologies for Frequency Ancillary Services in Future Multi-energy Sustainable Power Systems
Mar 2019
Publication
This paper examines the prospect of PEM (Proton Exchange Membrane) electrolyzers and fuel cells to partake in European electrical ancillary services markets. First the current framework of ancillary services is reviewed and discussed emphasizing the ongoing European harmonization plans for future frequency balancing markets. Next the technical characteristics of PEM hydrogen technologies and their potential uses within the electrical power system are discussed to evaluate their adequacy to the requirements of ancillary services markets. Last a case study based on a realistic representation of the transmission grid in the north of the Netherlands for the year 2030 is presented. The main goal of this case study is to ascertain the effectiveness of PEM electrolyzers and fuel cells for the provision of primary frequency reserves. Dynamic generic models suitable for grid simulations are developed for both technologies including the required controllers to enable participation in ancillary services markets. The obtained results show that PEM hydrogen technologies can improve the frequency response when compared to the procurement with synchronous generators of the same reserve value. Moreover the fast dynamics of PEM electrolyzers and fuel cells can help mitigate the negative effects attributed to the reduction of inertia in the system.
Strategies for the Adoption of Hydrogen-Based Energy Storage Systems: An Exploratory Study in Australia
Aug 2022
Publication
A significant contribution to the reduction of carbon emissions will be enabled through the transition from a centralised fossil fuel system to a decentralised renewable electricity system. However due to the intermittent nature of renewable energy storage is required to provide a suitable response to dynamic loads and manage the excess generated electricity with utilisation during periods of low generation. This paper investigates the use of stationary hydrogen-based energy storage systems for microgrids and distributed energy resource systems. An exploratory study was conducted in Australia based on a mixed methodology. Ten Australian industry experts were interviewed to determine use cases for hydrogen-based energy storage systems’ requirements barriers methods and recommendations. This study suggests that the current cost of the electrolyser fuel cell and storage medium and the current low round-trip efficiency are the main elements inhibiting hydrogen-based energy storage systems. Limited industry and practical experience are barriers to the implementation of hydrogen storage systems. Government support could help scale hydrogen-based energy storage systems among early adopters and enablers. Furthermore collaboration and knowledge sharing could reduce risks allowing the involvement of more stakeholders. Competition and innovation could ultimately reduce the costs increasing the uptake of hydrogen storage systems.
The More the Merrier? Actors and Ideas in the Evolution of Germany Hydrogen Policy Discourse
Feb 2023
Publication
Hydrogen has set high hopes for decarbonization due to its flexibility and ability to decarbonize sectors of the economy where direct electrification appears unviable. Broad hydrogen policies have therefore started to emerge. Nevertheless it is still a rather niche technology not integrated or adopted at scale and not regulated through particular policy provisions. The involved stakeholders are thus still rushing to set the agenda over the issue. All this plays out publicly and shapes the public discourse. This paper explores how the composition of stakeholders their positions and the overall discourse structure have developed and accompanied the political agenda-setting in the early public debate on hydrogen in Germany. We use discourse network analysis of media where stakeholders' claims-making is documented and their positions can be tracked over time. The public discourse on hydrogen in Germany shows the expected evolution of statements in connection with the two milestones chosen for the analyses the initiation of the Gas 2030 Dialogue and the publication of the National Hydrogen Strategy. Interestingly the discourse was comparatively feeble in the immediate aftermath of the respective milestones but intensified in a consolidation phase around half a year later. Sequencing the discourse and contextualizing its content relative to political societal and economic conditions in a diachronic way is essential because it helps to avoid misinterpreting the development of stakeholders' standpoints as conflict-driven rather than mere repositioning. Thus we observed no discourse “polarization” even though potentially polarizing issues were already present in the debate.
Design of Fuel Cell Systems for Aviation: Representative Mission Profiles and Sensitivity Analyses
Apr 2019
Publication
The global transition to a clean and sustainable energy infrastructure does not stop at aviation. The European Commission defined a set of environmental goals for the “Flight Path 2050”: 75% CO2 reduction 90% NOx reduction and 65% perceived noise reduction. Hydrogen as an energy carrier fulfills these needs while it would also offer a tenable and flexible solution for intermittent large-scale energy storage for renewable energy networks. If hydrogen is used as an energy carrier there is no better device than a fuel cell to convert its stored chemical energy. In order to design fuel cell systems for passenger aircraft it is necessary to specify the requirements that the system has to fulfill. In this paper a statistical approach to analyze these requirements is presented which accounts for variations in the flight mission profile. Starting from a subset of flight data within the desired class (e.g. mid-range inter-European flights) a stochastic model of the random mission profile is inferred. This model allows for subsequent predictions under uncertainty as part of the aircraft design process. By using Monte Carlo-based sampling of flight mission profiles the range of necessary component sizes as well as optimal degrees of hybridization with a battery is explored and design options are evaluated. Furthermore Monte Carlo-based sensitivity analysis of performance parameters explores the potential of future technological developments. Results suggest that the improvement of the specific power of the fuel cell is the deciding factor for lowering the energy system mass. The specific energy of the battery has a low influence but acts in conjunction with the specific power of the fuel cell.
Hydrogen for the De-carbonization of the Resources and Energy Intensive Industries (REIIs)
Aug 2022
Publication
This study deals with the use of hydrogen for the de-carbonization of the Resources and Energy Intensive Industries (REIIs) and gives a specific insight of the situation of the steel-making industry. The growing use of hydrogen in our economy is synonym for an equal increase in electricity consumption. This results from the fact that the current most promising technologies of H2 production is water electrolysis. For this purpose the EU hydrogen strategy foresees a progressive ramp up of H2 production capacities. But bottlenecks (especially regarding energy needed for electrolysers) may occur. Capacities should reach 40 GW (around 10 Mt/y) by the end of 2030. The steel-making industry relies heavily on H2 to decarbonise its process (through direct iron ore reduction). Our study analyses the conditions under which this new process will be able to compete with both European and offshore existing carbonised assets (i.e. blast furnaces). It emphasises the need for integrated and consistent policies from carbon prices to the carbon border adjustment mechanism through carbon contracts for differences but also highlightsthat a better regulation of electricity prices should not be neglected.
Techno Environmental Assessment of Flettner Rotor as Assistance Propulsion System for LH2 Tanker Ship Fuelled by Hydrogen
Nov 2022
Publication
This study presents a novel design and development of a 280000 m3 liquefied hydrogen tanker ship by implementing a set of 6 Flettner rotors as an assistance propulsion system in conjunction with a combined-cycle gas turbine fuelled by hydrogen as a prime mover. The study includes assessment of the technical and environmental aspects of the developed design. Furthermore an established method was applied to simulate the LH2 tanker in different voyages and conditions to investigate the benefits of harnessing wind energy to assist combined-cycle gas turbine in terms of performance and emission reduction based on engine behaviour for different voyages under loaded and unloaded normal as well as 6 % degraded engine and varying ambient conditions. The results indicate that implementing a set of 6 Flettner rotors for the LH2 tanker ship has the potential to positively impact the performance and lead to environmental benefits. A maximum contribution power of around 1.8 MW was achieved in the winter season owing to high wind speed and favourable wind direction. This power could save approximately 3.6 % of the combined-cycle gas turbine total output power (50 MW) and cause a 3.5 % reduction in NOx emissions.
Thermochemical Recuperation to Enable Efficient Ammonia-Diesel Dual-Fuel Combustion in a Compression Ignition Engine
Nov 2021
Publication
A thermochemical recuperation (TCR) reactor was developed and experimentally evaluated with the objective to improve dual-fuel diesel–ammonia compression ignition engines. The novel system simultaneously decomposed ammonia into a hydrogen-containing mixture to allow high diesel fuel replacement ratios and oxidized unburned ammonia emissions in the exhaust overcoming two key shortcomings of ammonia combustion in engines from the previous literature. In the experimental work a multi-cylinder compression ignition engine was operated in dual-fuel mode using intake-fumigated ammonia and hydrogen mixtures as the secondary fuel. A full-scale catalytic TCR reactor was constructed and generated the fuel used in the engine experiments. The results show that up to 55% of the total fuel energy was provided by ammonia on a lower heating value basis. Overall engine brake thermal efficiency increased for modes with a high exhaust temperature where ammonia decomposition conversion in the TCR reactor was high but decreased for all other modes due to poor combustion efficiency. Hydrocarbon and soot emissions were shown to increase with the replacement ratio for all modes due to lower combustion temperatures and in-cylinder oxidation processes in the late part of heat release. Engine-out oxides of nitrogen (NOx) emissions decreased with increasing diesel replacement levels for all engine modes. A higher concentration of unburned ammonia was measured in the exhaust with increasing replacement ratios. This unburned ammonia predominantly oxidized to NOx species over the oxidation catalyst used within the TCR reactor. Ammonia substitution thus increased post-TCR reactor ammonia and NOx emissions in this work. The results show however that engine-out NH3 -to-NOx ratios were suitable for passive selective catalytic reduction thus demonstrating that both ammonia and NOx from the engine could be readily converted to N2 if the appropriate catalyst were used in the TCR reactor.
Case Studies of Energy Storage with Fuel Cells and Batteries for Stationary and Mobile Applications
Mar 2017
Publication
In this paper hydrogen coupled with fuel cells and lithium-ion batteries are considered as alternative energy storage methods. Their application on a stationary system (i.e. energy storage for a family house) and a mobile system (i.e. an unmanned aerial vehicle) will be investigated. The stationary systems designed for off-grid applications were sized for photovoltaic energy production in the area of Turin Italy to provide daily energy of 10.25 kWh. The mobile systems to be used for high crane inspection were sized to have a flying range of 120 min one being equipped with a Li-ion battery and the other with a proton-exchange membrane fuel cell. The systems were compared from an economical point of view and a life cycle assessment was performed to identify the main contributors to the environmental impact. From a commercial point of view the fuel cell and the electrolyzer being niche products result in being more expensive with respect to the Li-ion batteries. On the other hand the life cycle assessment (LCA) results show the lower burdens of both technologies.
Ammonia, Methane and Hydrogen for Gas Turbines
Aug 2015
Publication
Ammonia has been identified as a sustainable fuel for transport and power applications. Similar to hydrogen ammonia is a synthetic product that can be obtained either from fossil fuels biomass or other renewable sources. Since the 1960’s considerable research has taken place to develop systems capable of burning the material in gas turbines. However it is not until recently that interest in ammonia has regained some momentum in the energy agenda as it is a carbon free carrier and offers an energy density higher than compressed hydrogen. . Therefore this work examines combustion stability and emissions from gaseous ammonia blended with methane or hydrogen in gas turbines. Experiments were carried out in a High Pressure Combustion Rig under atmospheric conditions employing a bespoke generic swirl burner. OH* Chemiluminescense was used for all trials to determine reactivity of the radical. Emissions were measured and correlated to equilibrium calculations using GASEQ. Results show that efficient combustion can be achieved with high power but at very narrow equivalence ratios using both hydrogen and methane blends. Moreover low concentrations of OH radicals are observed at high hydrogen content probably as a consequence of the high NH2 production.
Critical Parameters Controlling Wettability in Hydrogen Underground Storage - An Analytical Study
Sep 2022
Publication
Hypothesis.<br/>The large-scale implementation of hydrogen economy requires immense storage spaces to facilitate the periodic storage/production cycles. Extensive modelling of hydrogen transport in porous media is required to comprehend the hydrogen-induced complexities prior to storage to avoid energy loss. Wettability of hydrogen-brine-rock systems influence flow properties (e.g. capillary pressure and relative permeability curves) and the residual saturations which are all essential for subsurface hydrogen systems.<br/>Model.<br/>This study aims to understand which parameters critically control the contact angle for hydrogen-brine-rock systems using the surface force analysis following the DLVO theory and sensitivity analysis. Furthermore the effect of roughness is studied using the Cassie-Baxter model.<br/>Findings.<br/>Our results reveal no considerable difference between H2 and other gases such as N2. Besides the inclusion of roughness highly affects the observed apparent contact angles and even lead to water-repelling features. It was observed that contact angle does not vary significantly with variations of surface charge and density at high salinity which is representative for reservoir conditions. Based on the analysis it is speculated that the influence of roughness on contact angle becomes significant at low water saturation (i.e. high capillary pressure).
Recent Advances in Alkaline Exchange Membrane Water Electrolysis and Electrode Manufacturing
Oct 2021
Publication
Water electrolysis to obtain hydrogen in combination with intermittent renewable energy resources is an emerging sustainable alternative to fossil fuels. Among the available electrolyzer technologies anion exchange membrane water electrolysis (AEMWE) has been paid much attention because of its advantageous behavior compared to other more traditional approaches such as solid oxide electrolyzer cells and alkaline or proton exchange membrane water electrolyzers. Recently very promising results have been obtained in the AEMWE technology. This review paper is focused on recent advances in membrane electrode assembly components paying particular attention to the preparation methods for catalyst coated on gas diffusion layers which has not been previously reported in the literature for this type of electrolyzers. The most successful methodologies utilized for the preparation of catalysts including co-precipitation electrodeposition sol–gel hydrothermal chemical vapor deposition atomic layer deposition ion beam sputtering and magnetron sputtering deposition techniques have been detailed. Besides a description of these procedures in this review we also present a critical appraisal of the efficiency of the water electrolysis carried out with cells fitted with electrodes prepared with these procedures. Based on this analysis a critical comparison of cell performance is carried out and future prospects and expected developments of the AEMWE are discussed.
Potential of Producing Green Hydrogen in Jordan
Nov 2022
Publication
Green hydrogen is becoming an increasingly important energy supply source worldwide. The great potential for the use of hydrogen as a sustainable energy source makes it an attractive energy carrier. In this paper we discuss the potential of producing green hydrogen in Jordan. Aqaba located in the south of Jordan was selected to study the potential for producing green hydrogen due to its proximity to a water source (i.e. the Red Sea). Two models were created for two electrolyzer types using MATLAB. The investigated electrolyzers were alkaline water (ALK) and polymeric electrolyte membrane (PEM) electrolyzers. The first model was used to compare the required capacity of the PV solar system using ALK and PEM from 2022 to 2025 depending on the learning curves for the development of these technologies. In addition this model was used to predict the total investment costs for the investigated electrolyzers. Then a techno-economic model was constructed to predict the feasibility of using this technology by comparing the use of a PV system and grid electricity as sources for the production of hydrogen. The net present value (NPV) and levelized cost of hydrogen (LCOH) were used as indicators for both models. The environmental effect according to the reduction of CO2 emissions was also taken into account. The annual production of hydrogen was 70.956 million kg. The rate of hydrogen production was 19.3 kg/s and 1783 kg/s for ALK and PEM electrolyzers respectively. The LCOH was 4.42 USD/kg and 3.13 USD/kg when applying electricity from the grid and generated by the PV system respectively. The payback period to cover the capital cost of the PV system was 11 years of the project life with a NPV of USD 441.95 million. Moreover CO2 emissions can be reduced by 3042 tons/year by using the PV as a generation source instead of fossil fuels to generate electricity. The annual savings with respect to the reduction of CO2 emissions was USD 120135.
The Potential of Zero-carbon Bunker Fuels in Developing Countries
Apr 2015
Publication
To meet the climate targets set forth in the International Maritime Organization’s Initial GHG Strategy the maritime transport sector needs to abandon the use of fossil-based bunker fuels and turn toward zero-carbon alternatives which emit zero or at most very low greenhouse gas (GHG) emissions throughout their lifecycles. This report “The Potential of Zero-Carbon Bunker Fuels in Developing Countries” examines a range of zero-carbon bunker fuel options that are considered to be major contributors to shipping’s decarbonized future: biofuels hydrogen and ammonia and synthetic carbon-based fuels. The comparison shows that green ammonia and green hydrogen strike the most advantageous balance of favorable features due to their lifecycle GHG emissions broader environmental factors scalability economics and technical and safety implications. Furthermore the report finds that many countries including developing countries are very well positioned to become future suppliers of zero-carbon bunker fuels—namely ammonia and hydrogen. By embracing their potential these countries would be able to tap into an estimated $1+ trillion future fuel market while modernizing their own domestic energy and industrial infrastructure. However strategic policy interventions are needed to unlock these potentials.
Numerical Investigation of Thermal Hazards from Under-expanded Hydrogen Jet Fires using a New Scheme for the Angular Discretization of the Radiative Intensity
Sep 2021
Publication
In the context of a numerical investigation of thermal hazards from two under-expanded hydrogen jet fires results from a newly-developed thermal radiation module of the ADREA-HF computational fluid dynamics (CFD) code were validated against two physical experiments. The first experiment was a vertical under-expanded hydrogen jet fire at 170 bar with the objective of the numerical investigation being to capture the spatial distribution of the radial radiative heat flux at a given time instant. In the second case a horizontal under-expanded hydrogen jet fire at 340 bar was considered. Here the objective was to capture the temporal evolution of the radial radiative heat flux at selected fixed points in space. The numerical study employs the eddy dissipation model for combustion and the finite volume method (FVM) for the calculation of the radiative intensity. The FVM was implemented using a novel angular discretization scheme. By dividing the unit sphere into an arbitrary number of exactly equal angular control volumes this new scheme allows for more flexibility and efficiency. A demonstration of numerical convergence as a function the number of both spatial and angular control volumes was performed.
Development and Mechanistic Studies of Ternary Nanocomposites for Hydrogen Production from Water Splitting to Yield Sustainable/Green Energy and Environmental Remediation
Mar 2022
Publication
Photocatalysts lead vitally to water purifications and decarbonise environment each by wastewater treatment and hydrogen (H2 ) production as a renewable energy source from waterphotolysis. This work deals with the photocatalytic degradation of ciprofloxacin (CIP) and H2 production by novel silver-nanoparticle (AgNPs) based ternary-nanocomposites of thiolated reducegraphene oxide graphitic carbon nitride (AgNPs-S-rGO2%@g-C3N4 ) material. Herein the optimised balanced ratio of thiolated reduce-graphene oxide in prepared ternary-nanocomposites played matchlessly to enhance activity by increasing the charge carriers’ movements via slowing down charge-recombination ratios. Reduced graphene oxide (rGO) >2 wt.% or < 10 nm. Therefore AgNPs-S-rGO2%@g-C3N4 has 3772.5 µmolg−1 h −1 H2 production which is 6.43-fold higher than g-C3N4 having cyclic stability of 96% even after four consecutive cycles. The proposed mechanism for AgNPs-S-rGO2%@g-C3N4 revealed that the photo-excited electrons in the conduction-band of g-C3N4 react with the adhered water moieties to generate H2 .
Everything About Hydrogen Podcast: Hydrogen in the E-Mobility Sector
Oct 2021
Publication
Quantron AG was created in 2019 as a high-tech spin-off of the well-known Haller GmbH & Co. KG with the vision of paving the way for e-mobility in inner-city and regional passenger and cargo transportation. Quantron AG combines innovative ability and expertise in e-vans e-trucks and e-buses with the long-standing knowledge and experience of Haller GmbH & Co. KG in the commercial vehicle sector. The company's approach to e-Mobility is defined by its commitment to leveraging the most effective zero-emission vehicle technology for the use case which means Quantron is building both hydrogen fuel cell electric vehicles (FCEVs) and battery electric vehicles (BEVs) for its clients.
The podcast can be found on the website
The podcast can be found on the website
Everything About Hydrogen Podcast: Supplying the Building Blocks of an Energy Revolution
Apr 2021
Publication
On this episode of Everything About Hydrogen the team is joined by Sam French Business Development Director at JM who spent some time speaking with us about the transition from grey hydrogen to low-carbon generation technologies and what steps the UK - and countries all over the world - to use hydrogen as part of the pathway to a sustainable energy future.
The podcast can be found on their website
The podcast can be found on their website
Effect of Carbon Concentration and Carbon Bonding Type on the Melting Characteristics of Hydrogen-reduced Iron Ore Pellets
Oct 2022
Publication
Decarbonization of the steel industry is one of the pathways towards a fossil-fuel-free environment. The steel industry is one of the top contributors to greenhouse gas emissions. Most of these emissions are directly linked to the use of a fossil-fuelbased reductant. Replacing the fossil-based reductant with green H2 enables the transition towards a fossil-free steel industry. The carbon-free iron produced will cause the refining and steelmaking operations to have a starting point far from today’s operations. In addition to carbon being an alloying element in steel production carbon addition controls the melting characteristics of the reduced iron. In the present study the effect of carbon content and form (cementite/graphite) in hydrogen-reduced iron ore pellets on their melting characteristics was examined by means of a differential thermal analyser and optical dilatometer. Carburized samples with a carbon content < 2 wt % did not show any initial melting at the eutectic temperature. At and above 2 wt % the carburized samples showed an initial melting at the eutectic temperature irrespective of the carbon content. However the absorbed heat varies with varied carbon content. The carbon form does not affect the initial melting temperature but it affects the melting progression. Carburized samples melt homogenously while melting of iron-graphite mixtures occurs locally at the interface between iron and carbon particles and when the time is not long enough melting might not occur to any significant extent. Therefore at any given carbon content > 2 wt % the molten fraction is higher in the case of carburized samples which is indicated by the amount of absorbed melting heat.
A Novel Optimal Power Control for a City Transit Hybrid Bus Equipped with a Partitioned Hydrogen Fuel Cell Stack
May 2020
Publication
The development of more sustainable and zero-emissions collective transport solutions could play a very important measure in the near future within smart city policies. This paper tries to give a contribution to this aim proposing a novel approach to fuel cell vehicle design and operation. Traditional difficulties experienced in fuel cell transient operation are in fact normally solved in conventional vehicle prototypes through the hybridization of the propulsion system and with the complete fulfillment of transients in road energy demand through a high-capacity onboard energy storage device. This makes it normally necessary to use Li-ion battery solutions accepting their restrictions in terms of weight costs energy losses limited lifetime and environmental constraints. The proposed solution instead introduces a partitioning of the hydrogen fuel cell (FC) and novel optimal power control strategy with the aim of limiting the capacity of the energy storage still avoiding FC transient operation. The limited capacity of the resulting energy storage systems which instead has to answer higher power requests makes it possible to consider the utilization of a high-speed flywheel energy storage system (FESS) in place of high energy density Li-ion batteries. The proposed control strategy was validated by vehicle simulations based on a modular and parametric model; input data were acquired experimentally on an operating electric bus in real traffic conditions over an urban bus line. Simulation results highlight that the proposed control strategy makes it possible to obtain an overall power output for the FC stacks which better follows road power demands and a relevant downsizing of the FESS device.
RANS Simulation of Hydrogen Flame Propagation in an Acceleration Tube: Examination of k-ω SST Model Parameters
Sep 2021
Publication
Due to practical computational resource limits current simulations of premixed turbulent combustion experiments are often performed using simplified turbulence treatment. From all available RANS models k-ε and k-ω SST are the most widely used. k-ω SST model is generally expected to be more accurate in bounded geometries since it corresponds to k-ε model further from the walls but switches to more appropriate k-ω model near the walls. However k-ε is still widely used and in some instances is shown to provide better results. In this paper we perform RANS simulations of premixed hydrogen flame propagation in an acceleration tube using k-ε and k-ω SST models. Accuracy of the models is assessed by comparing obtained results with the experiment. In order to better understand differences between k-ε and k-ω-SST results parameters of main k-ω-SST model features are examined. The distribution of the blending functions values and corresponding zones of are analysed in relation to flame position and resulting observed propagation velocity. We show that in the simulated case biggest difference between k-ω-SST and k-ε model results can be attributed to turbulent eddy viscosity limiting by shear strain rate in the k-ω-SST model.
The Hydrogen Color Spectrum: Techno-Economic Analysis of the Available Technologies for Hydrogen Production
Feb 2023
Publication
Hydrogen has become the most promising energy carrier for the future. The spotlight is now on green hydrogen produced with water electrolysis powered exclusively by renewable energy sources. However several other technologies and sources are available or under development to satisfy the current and future hydrogen demand. In fact hydrogen production involves different resources and energy loads depending on the production method used. Therefore the industry has tried to set a classification code for this energy carrier. This is done by using colors that reflect the hydrogen production method the resources consumed to produce the required energy and the number of emissions generated during the process. Depending on the reviewed literature some colors have slightly different definitions thus making the classifications imprecise. Therefore this techno-economic analysis clarifies the meaning of each hydrogen color by systematically reviewing their production methods consumed energy sources and generated emissions. Then an economic assessment compares the costs of the various hydrogen colors and examines the most feasible ones and their potential evolution. The scientific community and industry’s clear understanding of the advantages and drawbacks of each element of the hydrogen color spectrum is an essential step toward reaching a sustainable hydrogen economy
Numerical Modeling of Energy Systems Based on Micro Gas Turbine: A Review
Jan 2022
Publication
In the context of the great research pulse on clean energy transition distributed energy systems have a key role especially in the case of integration of both renewable and traditional energy sources. The stable interest in small-scale gas turbines can further increase owing to their flexibility in both operation and fuel supply. Since their not-excellent electrical efficiency research activities on micro gas turbine (MGT) are focused on the performance improvements that are achievable in several ways like modifying the Brayton cycle integrating two or more plants using cleaner fuels. Hence during the last decades the growing interest in MGT-based energy systems encouraged the development of many numerical approaches aimed to provide a reliable and effective prediction of the energy systems’ behavior. Indeed numerical modeling can help to individuate potentialities and issues of each enhanced layout or hybrid energy system and this review aims to discuss the various layout solutions proposed by researchers with particular attention to recent publications highlighting the adopted modeling approaches and methods.
Using Multicriteria Decision Making to Evaluate the Risk of Hydrogen Energy Storage and Transportation in Cities
Jan 2023
Publication
Hydrogen is an environmentally friendly source of renewable energy. Energy generation from hydrogen has not yet been widely commercialized due to issues related to risk management in its storage and transportation. In this paper the authors propose a hybrid multiple-criteria decision-making (MCDM)-based method to manage the risks involved in the storage and transportation of hydrogen (RSTH). First we identified the key points of the RSTH by examining the relevant literature and soliciting the opinions of experts and used this to build a prototype of its decision structure. Second we developed a hybrid MCDM approach called the D-ANP that combined the decision-making trial and evaluation laboratory (DEMENTEL) with the analytic network process (ANP) to obtain the weight of each point of risk. Third we used fuzzy evaluation to assess the level of the RSTH for Beijing China where energy generation using hydrogen is rapidly advancing. The results showed that the skills of the personnel constituted the most important risk-related factor and environmental volatility and the effectiveness of feedback were root factors. These three factors had an important impact on other factors influencing the risk of energy generation from hydrogen. Training and technical assistance can be used to mitigate the risks arising due to differences in the skills of personnel. An appropriate logistics network and segmented transportation for energy derived from hydrogen should be implemented to reduce environmental volatility and integrated supply chain management can help make the relevant feedback more effective.
Thermodynamics, Energy Dissipation, and Figures of Merit of Energy Storage Systems—A Critical Review
Sep 2021
Publication
The path to the mitigation of global climate change and global carbon dioxide emissions avoidance leads to the large-scale substitution of fossil fuels for the generation of electricity with renewable energy sources. The transition to renewables necessitates the development of large-scale energy storage systems that will satisfy the hourly demand of the consumers. This paper offers an overview of the energy storage systems that are available to assist with the transition to renewable energy. The systems are classified as mechanical (PHS CAES flywheels springs) electromagnetic (capacitors electric and magnetic fields) electrochemical (batteries including flow batteries) hydrogen and thermal energy storage systems. Emphasis is placed on the magnitude of energy storage each system is able to achieve the thermodynamic characteristics the particular applications the systems are suitable for the pertinent figures of merit and the energy dissipation during the charging and discharging of the systems.
The Direct Reduction of Iron Ore with Hydrogen
Aug 2022
Publication
The steel industry represents about 7% of the world’s anthropogenic CO2 emissions due to the high use of fossil fuels. The CO2 -lean direct reduction of iron ore with hydrogen is considered to offer a high potential to reduce CO2 emissions and this direct reduction of Fe2O3 powder is investigated in this research. The H2 reduction reaction kinetics and fluidization characteristics of fine and cohesive Fe2O3 particles were examined in a vibrated fluidized bed reactor. A smooth bubbling fluidization was achieved. An increase in external force due to vibration slightly increased the pressure drop. The minimum fluidization velocity was nearly independent of the operating temperature. The yield of the direct H2 -driven reduction was examined and found to exceed 90% with a maximum of 98% under the vibration of ~47 Hz with an amplitude of 0.6 mm and operating temperatures close to 500 ◦C. Towards the future of direct steel ore reduction cheap and “green” hydrogen sources need to be developed. H2 can be formed through various techniques with the catalytic decomposition of NH3 (and CH4 ) methanol and ethanol offering an important potential towards production cost yield and environmental CO2 emission reductions.
Future Energy Scenarios 2021
Jul 2022
Publication
Our Future Energy Scenarios (FES) draw on hundreds of experts’ views to model four credible energy pathways for Britain over coming decades. Matthew Wright our head of strategy and regulation outlines what the 2021 outlook means for consumers society and the energy system itself.<br/>This year’s Future Energy Scenarios insight reveals a glimpse of a Britain that is powered with net zero carbon emissions.<br/>Our analysis shows that our country can achieve its legally-binding carbon reduction targets: in three out of four scenarios in the analysis the country reaches net zero carbon emissions by 2050 with Leading the Way – our most ambitious scenario – achieving it in 2047 and becoming net negative by 2050.
Environmental-economic Sustainability of Hydrogen and Ammonia Fuels for Short Sea Shipping Operations
Jan 2024
Publication
Alternative fuels of low or zero carbon content can decarbonise the shipping operations. This study aims at assessing the lifetime environmental-economic sustainability of ammonia and hydrogen as alternatives to diesel fuel for short sea shipping cargo vessels. A model is employed to calculate key performance indicators representing the lifetime financial sustainability and environmental footprint of the case ship using a realistic operating profile and considering several scenarios with different diesel substitution rates. Scenarios meeting the carbon emissions reduction targets set by the International Maritime Organisation (IMO) for 2030 are identified whereas policy measures for their implementation including the emissions taxation are discussed. The derived results demonstrate that the future implementation of carbon emissions taxation in the ranges of 136–965 €/t for hydrogen and 356–2647 €/t for ammonia can support these fuels financial sustainability in shipping. This study provides insights for adopting zero-carbon fuels and as such impacts the de-risking of shipping decarbonisation.
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