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Study on Introduction of CO2 Free Energy to Japan with Liquid Hydrogen
Jul 2015
Publication
In Japan both CO2 (Carbon dioxide) emission reduction and energy security are the very important social issues after Fukushima Daiichi accident. On the other hand FCV (Fuel Cell Vehicle) using hydrogen will be on the market in 2015. Introducing large mass hydrogen energy is being expected as expanding hydrogen applications or solution to energy issues of Japan. And then the Japanese government announced the road map for introducing hydrogen energy supply chain in this June2014. Under these circumstances imported CO2 free hydrogen will be one of the solutions for energy security and CO2 reduction if the hydrogen price is affordable. To achieve this Kawasaki Heavy Industries Ltd. (KHI) performed a feasibility study on CO2-free hydrogen energy supply chain from Australian brown coal linked with CCS (Carbon dioxide Capture and Storage) to Japan. In the study hydrogen production systems utilizing brown coal gasification and LH2 (liquid hydrogen) systems as storing and transporting hydrogen are examined. This paper shows the possibility of realizing the CO2 free hydrogen supply chain the cost breakdown of imported hydrogen cost its cost competitiveness with conventional fossil and LH2 systems as key technologies of the hydrogen energy chain.
Fire Spread Scenarios Involving Hydrogen Vehicles
Sep 2021
Publication
Fire spread between vehicles provides a potential risk in parking areas with many vehicles. Several reported very large fires caused the loss of a great number of vehicles. These fires seem to be in contradiction to the European design rules for car parks assuming only a very limited number of vehicles may be on fire at the same time. The fire spread in a car park environment is dependent on many factors of both the vehicles and the structure e.g. the latter has an impact on the rate of fire spread due to reradiation of the vehicles heat release. Therefore a CFD model is established to develop a tool to assess vehicles and better understand fire scenarios in different structures. Further the model enables testing of building design to prevent and mitigate such fires scenarios involving hydrogen vehicles. In this study a real layout of a car park is modelled to investigate the effects of hydrogen emergency releases that have used different TPRD diameters. The results provide insight into the behaviour of hydrogen cars and the release pattern of the TPRD's as well as the temperature development of the concrete ceiling and concrete beams above the cars. It shows that the TPRD diameter has a little effect on the TPRD activation time of the no.1 vehicle when the amount of H2 in the tank is the same. For the surface temperature of the ceiling and beam the peak temperature for a 1mm diameter TPRD release is found highest.
Greenhouse Gas Emissions of Conventional and Alternative Vehicles: Predictions Based on Energy Policy Analysis in South Korea
Mar 2020
Publication
This paper compares the well-to-wheel (WTW) greenhouse gas (GHG) emissions of representative vehicle types–internal combustion engine vehicle (ICEV) hybrid electric vehicle (HEV) plug-in hybrid electric vehicle (PHEV) battery electric vehicle (BEV) and fuel cell electric vehicle (FCEV)–in the future (2030) based on a WTW analysis for the present (2017) and an analysis of various energy policies that could affect future emissions. South Korea was selected as the target region because it has detailed energy policies related to alternative vehicles. The WTW analysis for the present was performed based on three sets of subordinate analyses: (1) life cycle analyses of eight base fuels; (2) life cycle analyses of electricity and hydrogen; and (3) analyses of the fuel economies of seven vehicle types. From the WTW analysis for the present the national average WTW GHG emissions of ICEV-gasoline ICEV-diesel ICEV-liquefied petroleum gas HEV PHEV BEV and FCEV were calculated as 225 233 201 159 133 109 and 55 g-CO2-eq./km respectively. For calculating the WTW GHG emissions in the future two policies regarding electricity production and three policies regarding hydrogen production were analysed. Three cases with varying the degrees of improvements in fuel economies were considered. Six future scenarios were constructed and each scenario represented the case in which each energy policy is enacted. In the reference scenario for compact car the WTW GHG emissions of ICEVs-gasoline HEV PHEV BEV-200 mile FCEV were analysed as 161 110 97 86 and 91 g-CO2-eq./km respectively. The differences between ICEV/HEV and BEV were predicted to decrease in the future mainly due to larger improvements of ICEV/HEV in fuel economies compared to that of BEV. The future life cycle GHG emissions of electricity and hydrogen were calculated according to energy policy. Both two policies regarding power generation were confirmed to increase the benefits of utilizing BEVs but current energy policy regarding hydrogen production were confirmed to decrease the benefits of utilizing FCEVs. Based on the comprehensive results of this study a framework was proposed to evaluate the impacts of an energy policy regarding electricity and hydrogen production on the benefits of using BEVs and FCEVs compared to using HEVs and ICEVs. This framework can also be utilized in other countries when they assess and establish their energy policies.
Optimal Day-ahead Dispatch of an Alkaline Electrolyser System Concerning Thermal–electric Properties and State-transitional Dynamics
Oct 2021
Publication
Green hydrogen is viewed as a promising energy carrier for sustainable development goals. However it has suffered from high costs hindering its implementation. For a stakeholder who considers both renewable energy and electrolysis units it is important to exploit the flexibility of such portfolios to maximize system operational revenues. To this end an electrolyser model that can characterize its dynamic behavior is required in both electric and thermal aspects. In this paper we develop a comprehensive alkaline electrolyser model that is capable of describing its hydrogen production properties temperature variations and state transitions (among production stand-by and off states). This model is further used to study the optimal dispatch of an electrolyser based on a real-world hybrid wind/electrolyser system. The results show the model can effectively capture the coupling between thermal–electric dynamics and on–off performance of an electrolyser. The flexible operation strategy based on this model is proven to significantly increase daily revenues under different spot price conditions for electricity. Comparing the model with the ones derived from conventional modeling methods reveals this model offers more operating details and highlights several operational features such as the preference for working at partial load conditions although at the expense of more computing resources. It is suggested to use this model in studies related to energy integration operation planning and control scheme development in which the multi-domain dynamic properties of electrolysers in electricity/gas/heat need to be properly characterized. A sensitivity analysis on key parameters of such electrolyser system is also introduced to connect the daily operation with long-term planning.
Combustion Characterization in a Diffusive Gas Turbine Burner for Hydrogen-Compliant Applications
Jun 2022
Publication
The target of net-zero emissions set by the 2015 Paris Agreement has strongly commissioned the energy production sector to promote decarbonization renewable sources exploitation and systems efficiency. In this framework the utilization of hydrogen as a long-term energy carrier has great potential. This paper is concerned with the combustion characterization in a non-premixed gas turbine burner originally designed for natural gas when it is fed with NG-H2 blends featuring hydrogen content from 0 to 50% in volume. The final aim is to retrofit a 40 MW gas turbine. Starting from the operational data of the engine a CFD model of the steady-state combustion process has been developed with reference to the base load NG conditions by reducing the fuel mass-flow rate by up to 17% to target the baseline turbine inlet temperature. When the fuel is blended with hydrogen for a given temperature at turbine inlet an increase in the peak temperature up to 800 K is obtained if no countermeasures are taken. Furthermore the flame results are more intense and closer to the injector in the case of hydrogen blending. The results of this work hint at the necessity of carefully analyzing the possible NOx compensation strategies as well as the increased thermal stresses on the injector.
Towards Computer-Aided Graphene Covered TiO2-Cu(CuxOy) Composite Design for the Purpose of Photoinduced Hydrogen Evolution
May 2021
Publication
In search a hydrogen source we synthesized TiO2-Cu-graphene composite photocatalyst for hydrogen evolution. The catalyst is a new and unique material as it consists of copper-decorated TiO2 particles covered tightly in graphene and obtained in a fluidized bed reactor. Both reduction of copper from Cu(CH3COO) at the surface of TiO2 particles and covering of TiO2-Cu in graphene thin layer by Chemical Vapour Deposition (CVD) were performed subsequently in the flow reactor by manipulating the gas composition. Obtained photocatalysts were tested in regard to hydrogen generation from photo-induced water conversion with methanol as sacrificial agent. The hydrogen generation rate for the most active sample reached 2296.27 µmol H2 h−1 gcat−1. Combining experimental and computational approaches enabled to define the optimum combination of the synthesis parameters resulting in the highest photocatalytic activity for water splitting for green hydrogen production. The results indicate that the major factor affecting hydrogen production is temperature of the TiO2-Cu-graphene composite synthesis which in turn is inversely correlated to photoactivity.
Analysis of Trends and Emerging Technologies in Water Electrolysis Research Based on a Computational Method: A Comparison with Fuel Cell Research
Feb 2018
Publication
Water electrolysis for hydrogen production has received increasing attention especially for accumulating renewable energy. Here we comprehensively reviewed all water electrolysis research areas through computational analysis using a citation network to objectively detect emerging technologies and provide interdisciplinary data for forecasting trends. The results show that all research areas increase their publication counts per year and the following two areas are particularly increasing in terms of number of publications: “microbial electrolysis” and “catalysts in an alkaline water electrolyzer (AWE) and in a polymer electrolyte membrane water electrolyzer (PEME).”. Other research areas such as AWE and PEME systems solid oxide electrolysis and the whole renewable energy system have recently received several review papers although papers that focus on specific technologies and are cited frequently have not been published within the citation network. This indicates that these areas receive attention but there are no novel technologies that are the center of the citation network. Emerging technologies detected within these research areas are presented in this review. Furthermore a comparison with fuel cell research is conducted because water electrolysis is the reverse reaction to fuel cells and similar technologies are employed in both areas. Technologies that are not transferred between fuel cells and water electrolysis are introduced and future water electrolysis trends are discussed.
HyDeploy2 : Trial Management
May 2021
Publication
The trial management philosophy of the Winlaton trial within HyDeploy2 has been developed to enable the overall objectives of the project to be achieved; the safe demonstration of operating a Gas Distribution Network (GDN) on a blend of natural gas and hydrogen. The approach taken to develop the management philosophy of the Winlaton trial has been to continue the trial management strategies deployed for the Keele trial under HyDeploy albeit with site specific modifications where necessary. This document provides an overview of the management and governance processes associated with the trial itself.<br/>Click on the supplement tab to view the other documents from this report
Alkaline Water Electrolysis Powered by Renewable Energy: A Review
Feb 2020
Publication
Alkaline water electrolysis is a key technology for large-scale hydrogen production powered by renewable energy. As conventional electrolyzers are designed for operation at fixed process conditions the implementation of fluctuating and highly intermittent renewable energy is challenging. This contribution shows the recent state of system descriptions for alkaline water electrolysis and renewable energies such as solar and wind power. Each component of a hydrogen energy system needs to be optimized to increase the operation time and system efficiency. Only in this way can hydrogen produced by electrolysis processes be competitive with the conventional path based on fossil energy sources. Conventional alkaline water electrolyzers show a limited part-load range due to an increased gas impurity at low power availability. As explosive mixtures of hydrogen and oxygen must be prevented a safety shutdown is performed when reaching specific gas contamination. Furthermore the cell voltage should be optimized to maintain a high efficiency. While photovoltaic panels can be directly coupled to alkaline water electrolyzers wind turbines require suitable converters with additional losses. By combining alkaline water electrolysis with hydrogen storage tanks and fuel cells power grid stabilization can be performed. As a consequence the conventional spinning reserve can be reduced which additionally lowers the carbon dioxide emissions.
Hydrogen Embrittlement Mechanism in Fatigue Behavior of Austenitic and Martensitic Stainless Steels
May 2018
Publication
In the present study the influence of hydrogen on the fatigue behavior of the high strength martensitic stainless steel X3CrNiMo13-4 and the metastable austenitic stainless steels X2Crni19-11 with various nickel contents was examined in the low and high cycle fatigue regime. The focus of the investigations were the changes in the mechanisms of short crack propagation. Experiments in laboratory air with uncharged and precharged specimen and uncharged specimen in pressurized hydrogen were carried out. The aim of the ongoing investigation was to determine and quantitatively describe the predominant processes of hydrogen embrittlement and their influence on the short fatigue crack morphology and crack growth rate. In addition simulations were carried out on the short fatigue crack growth in order to develop a detailed insight into the hydrogen embrittlement mechanisms relevant for cyclic loading conditions. It was found that a lower nickel content and a higher martensite content of the samples led to a higher susceptibility to hydrogen embrittlement. In addition crack propagation and crack path could be simulated well with the simulation model.
Blue Hydrogen
Apr 2021
Publication
The urgency of reaching net-zero emissions requires a rapid acceleration in the deployment of all emissions reducing technologies. Near-zero emissions hydrogen (clean hydrogen) has the potential to make a significant contribution to emissions reduction in the power generation transportation and industrial sectors.
As part of the Circular Carbon Economy: Keystone to Global Sustainability series with the Center on Global Energy Policy at Columbia University SIPA this report explores the potential contribution of blue hydrogen to climate mitigation.
The report looks at:
As part of the Circular Carbon Economy: Keystone to Global Sustainability series with the Center on Global Energy Policy at Columbia University SIPA this report explores the potential contribution of blue hydrogen to climate mitigation.
The report looks at:
- Cost drivers for renewable hydrogen and hydrogen produced with fossil fuels and CCS;
- Resource requirements and cost reduction opportunities for clean hydrogen; and
- Policy recommendations to drive investment in clean hydrogen production.
- Blue hydrogen is well placed to kickstart the rapid increase in the utilisation of clean hydrogen for climate mitigation purposes but requires strong and sustained policy to incentivise investment at the rate necessary to meet global climate goals.
Solid-State Hydrogen Storage Systems and the Relevance of a Gender Perspective
Sep 2021
Publication
This paper aims at addressing the exploitation of solid-state carriers for hydrogen storage with attention paid both to the technical aspects through a wide review of the available integrated systems and to the social aspects through a preliminary overview of the connected impacts from a gender perspective. As for the technical perspective carriers to be used for solid-state hydrogen storage for various applications can be classified into two classes: metal and complex hydrides. Related crystal structures and corresponding hydrogen sorption properties are reviewed and discussed. Fundamentals of thermodynamics of hydrogen sorption evidence the key role of the enthalpy of reaction which determines the operating conditions (i.e. temperatures and pressures). In addition it rules the heat to be removed from the tank during hydrogen absorption and to be delivered to the tank during hydrogen desorption. Suitable values for the enthalpy of hydrogen sorption reaction for operating conditions close to ambient (i.e. room temperature and 1–10 bar of hydrogen) are close to 30 kJ·molH2 −1 . The kinetics of the hydrogen sorption reaction is strongly related to the microstructure and to the morphology (i.e. loose powder or pellets) of the carriers. Usually the kinetics of the hydrogen sorption reaction is rather fast and the thermal management of the tank is the rate-determining step of the processes. As for the social perspective the paper arguments that as it occurs with the exploitation of other renewable innovative technologies a wide consideration of the social factors connected to these processes is needed to reach a twofold objective: To assess the extent to which a specific innovation might produce positive or negative impacts in the recipient socioeconomic system and from a sociotechnical perspective to explore the potential role of the social components and dynamics in fostering the diffusion of the innovation itself. Within the social domain attention has been paid to address the underexplored relationship between the gender perspective and the enhancement of hydrogen-related energy storage systems. This relationship is taken into account both in terms of the role of women in triggering the exploitation of hydrogen-based storage playing as experimenter and promoter and in terms of the intertwined impact of this innovation in their current conditions at work and in daily life.
CFD Modeling and Consequence Analysis of an Accidental Hydrogen Release in a Large Scale Facility
Sep 2013
Publication
In this study the consequences of an accidental release of hydrogen within large scale (>15000 m3) facilities were modelled. To model the hydrogen release an LES Navier–Stokes CFD solver called fireFoam was used to calculate the dispersion and mixing of hydrogen within a large scale facility. The performance of the CFD modelling technique was evaluated through a validation study using experimental results from a 1/6 scale hydrogen release from the literature and a grid sensitivity study. Using the model a parametric study was performed varying release rates and enclosure sizes and examining the concentrations that develop. The hydrogen dispersion results were then used to calculate the corresponding pressure loads from hydrogen-air deflagrations in the facility.
A Hydrogen Fuelled LH2 Tanker Ship Design
May 2021
Publication
This study provides a detailed philosophical view and evaluation of a viable design for a large liquid hydrogen tanker fuelled by liquid hydrogen. Established methods for determining tank sizing ship stability and ship characteristics were used to evaluate the preliminary design and performance of the liquefied hydrogen tanker named ‘JAMILA’ designed specifically to transport liquid hydrogen. JAMILA is designed around four large liquid hydrogen tanks with a total capacity of ∼280000 m3 and uses the boil-off gas for propulsion for the loaded leg of the journey. The ship is 370 m long 75 m wide and draws 10.012 m at full load. It has a fully loaded displacement tonnage of 232000 tonnes to carry 20000 tonnes of hydrogen. Its propulsion system contains a combined-cycle gas turbine of approximately 50 MW. The volume of the hydrogen cargo pressurised to 0.5 MPa primarily determines the size and displacement of the ship.
A Review of Hydrogen Direct Injection for Internal Combustion Engines: Towards Carbon-Free Combustion
Nov 2018
Publication
A paradigm shift towards the utilization of carbon-neutral and low emission fuels is necessary in the internal combustion engine industry to fulfil the carbon emission goals and future legislation requirements in many countries. Hydrogen as an energy carrier and main fuel is a promising option due to its carbon-free content wide flammability limits and fast flame speeds. For spark-ignited internal combustion engines utilizing hydrogen direct injection has been proven to achieve high engine power output and efficiency with low emissions. This review provides an overview of the current development and understanding of hydrogen use in internal combustion engines that are usually spark ignited under various engine operation modes and strategies. This paper then proceeds to outline the gaps in current knowledge along with better potential strategies and technologies that could be adopted for hydrogen direct injection in the context of compression-ignition engine applications—topics that have not yet been extensively explored to date with hydrogen but have shown advantages with compressed natural gas.
Performance Study on Methanol Steam Reforming Rib Micro-Reactor with Waste Heat Recovery
Mar 2020
Publication
Automobile exhaust heat recovery is considered to be an effective means to enhance fuel utilization. The catalytic production of hydrogen by methanol steam reforming is an attractive option for onboard mobile applications due to its many advantages. However the reformers of conventional packed bed type suffer from axial temperature gradients and cold spots resulting from severe limitations of mass and heat transfer. These disadvantages limit reformers to a low efficiency of catalyst utilization. A novel rib microreactor was designed for the hydrogen production from methanol steam reforming heated by automobile exhaust and the effect of inlet exhaust and methanol steam on reactor performance was numerically analyzed in detail with computational fluid dynamics. The results showed that the best operating parameters were the counter flow water-to-alcohol (W/A) of 1.3 exhaust inlet velocity of 1.1 m/s and exhaust inlet temperature of 773 K when the inlet velocity and inlet temperature of the reactant were 0.1 m/s and 493 K respectively. At this condition a methanol conversion of 99.4% and thermal efficiency of 28% were achieved together with a hydrogen content of 69.6%.
Thermodynamic Evaluation of Bi-directional Solid Oxide Cell Systems Including Year-round Cumulative Exergy Analysis
Jun 2018
Publication
Bi-directional solid oxide cell systems (Bi-SOC) are being increasingly considered as an electrical energy storage method and consequently as a means to boost the penetration of renewable energy (RE) and to improve the grid flexibility by power-to-gas electrochemical conversion. A major advantage of these systems is that the same SOC stack operates as both energy storage device (SOEC) and energy producing device (SOFC) based on the energy demand and production. SOEC and SOFC systems are now well-optimised as individual systems; this work studies the effect of using the bi-directionality of the SOC at a system level. Since the system performance is highly dependent on the cell-stack operating conditions this study improves the stack parameters for both operation modes. Moreover the year-round cumulative exergy method (CE) is introduced in the solid oxide cell (SOC) context for estimating the system exergy efficiencies. This method is an attempt to obtain more insightful exergy assessments since it takes into account the operational hours of the SOC system in both modes. The CE method therefore helps to predict more accurately the most efficient configuration and operating parameters based on the power production and consumption curves in a year. Variation of operating conditions configurations and SOC parameters show a variation of Bi-SOC system year-round cumulative exergy efficiency from 33% to 73%. The obtained thermodynamic performance shows that the Bi-SOC when feasible can prove to be a highly efficient flexible power plant as well as an energy storage system.
Review of Release Behavior of Hydrogen & Natural Gas Blends from Pipelines
Aug 2021
Publication
Hydrogen can be used to reduce carbon emissions by blending into other gaseous energy carriers such as natural gas. However hydrogen blending into natural gas has important implications for safety which need to be evaluated. Hydrogen has different physical properties than natural gas and these properties affect safety evaluations concerning a leak of the blended gas. The intent of this report is to begin to investigate the safety implications of blending hydrogen into the natural gas infrastructure with respect to a leak event from a pipeline. A literature review was conducted to identify existing data that will better inform future hazard and risk assessments for hydrogen/natural gas blends. Metrics with safety implications such as heat flux and dispersion behavior may be affected by the overall blend ratio of the mixture. Of the literature reviewed there was no directly observed separation of the hydrogen from the natural gas or methane blend. No literature was identified that experimentally examined unconfined releases such as concentration fields or concentration at specific distances. Computational efforts have predicted concentration fields by modified versions of existing engineering models but the validation of these models is limited by the unavailability of literature data. There are multiple literature sources that measured flame lengths and heat flux values which are both relevant metrics to risk and hazard assessments. These data can be more directly compared to the outputs of existing engineering models for validation.
The paper can be downloaded on their website
The paper can be downloaded on their website
Everything About Hydrogen Podcast: The year-end Round Up! 2020 in Review
Dec 2020
Publication
2020 has been a year for the history books! Some good most of it not so good; but 2020 has been a boom year for the future of hydrogen technologies. Patrick Chris and Andrew do their level best on this episode to talk about all the stories and the highlights of 2020 in under 50 minutes. Have a listen and let us know if we missed anything in our penultimate episode of 2020!
The podcast can be found on their website
The podcast can be found on their website
Hy4Heat Domestic Hydrogen Purge Procedures - Work Package 4
Jun 2021
Publication
The aim of this project was to review the current purge standards for UK domestic installations in particular IGEM/UP/1B and carry out experiments to assess the validity of those standards for use in hydrogen in order to understand and recommend safe purge practices for hydrogen in a domestic environment.
This report provides the results and conclusions relating to the relative safety of purging domestic installations to hydrogen compared to Natural Gas and the implications of releasing any purged gas
into an enclosed volume representing a small room.
The two high-level findings from this work are:
The risks with hydrogen are associated with a wide range of flammability with methane the risks are smaller and mainly in lower concentrations of gas in air. Because of this it is particularly important to ensure hydrogen pipes are appropriately purged.
This report provides the results and conclusions relating to the relative safety of purging domestic installations to hydrogen compared to Natural Gas and the implications of releasing any purged gas
into an enclosed volume representing a small room.
The two high-level findings from this work are:
- changeover to hydrogen will result in an increased risk of flammability inside the installation pipework
- changeover to hydrogen will result in a reduced risk of a build-up of flammable gas in any room where purging occurs.
The risks with hydrogen are associated with a wide range of flammability with methane the risks are smaller and mainly in lower concentrations of gas in air. Because of this it is particularly important to ensure hydrogen pipes are appropriately purged.
Potential Role of Natural Gas Infrastructure in China to Supply Low-carbon Gases During 2020–2050
Oct 2021
Publication
As natural gas (NG) demand increases in China the question arises how the NG infrastructure fit into a low greenhouse gas (GHG) emissions future towards 2050. Herein the potential role of the NG infrastructure in supplying low-carbon gases during 2020–2050 for China at a provincial resolution was analyzed for different scenarios. In total four low-carbon gases were considered in this study: biomethane bio-synthetic methane hydrogen and low-carbon synthetic methane. The results show that the total potential of low-carbon gas production can increase from 1.21 EJ to 5.25 EJ during 2020–2050 which can replace 20%–67% of the imported gas. In particular Yunnan and Inner Mongolia contribute 17% of China’s low-carbon gas production. As the deployment of NG infrastructure can be very different three scenarios replacing imported pipeline NG were found to reduce the expansion of gas infrastructure by 35%–42% while the three scenarios replacing LNG imports were found to increase infrastructure expansion by 31%–53% as compared to the base case. The cumulative avoided GHG emissions for the 6 analyzed scenarios were 6.0–8.3 Gt CO2. The GHG avoidance costs were highly influenced by the NG price. This study shows that the NG infrastructure has the potential to supply low-carbon gases in China thereby significantly reducing GHG emissions and increasing both China’s short- and long-term gas supply independence.
Comparative Analysis of Energy and Exergy Performance of Hydrogen Production Methods
Nov 2020
Publication
The study of the viability of hydrogen production as a sustainable energy source is a current challenge to satisfy the great world energy demand. There are several techniques to produce hydrogen either mature or under development. The election of the hydrogen production method will have a high impact on practical sustainability of the hydrogen economy. An important profile for the viability of a process is the calculation of energy and exergy efficiencies as well as their overall integration into the circular economy. To carry out theoretical energy and exergy analyses we have estimated proposed hydrogen production using different software (DWSIM and MATLAB) and reference conditions. The analysis consolidates methane reforming or auto-thermal reforming as the viable technologies at the present state of the art with reasonable energy and exergy efficiencies but pending on the impact of environmental constraints as CO2 emission countermeasures. However natural gas or electrolysis show very promising results and should be advanced in their technological and maturity scaling. Electrolysis shows a very good exergy efficiency due to the fact that electricity itself is a high exergy source. Pyrolysis exergy loses are mostly in the form of solid carbon material which has a very high integration potential into the hydrogen economy.
The Future of Clean Hydrogen in the United States: Views from Industry, Market Innovators, and Investors
Sep 2021
Publication
This report The Future of Clean Hydrogen in the United States: Views from Industry Market Innovators and Investors sheds light on the rapidly evolving hydrogen market based on 72 exploratory interviews with organizations across the current and emerging hydrogen value chain. This report is part of a series From Kilograms to Gigatons: Pathways for Hydrogen Market Formation in the United States which will build on this study to evaluate policy opportunities for further hydrogen development in the United States. The goal of the interviews was to provide a snapshot of the clean hydrogen investment environment and better understand organizations’ market outlook investment rationale and areas of interest. This interview approach was supported by traditional research methods to contextualize and enrich the qualitative findings. This report should be understood as input to a more extensive EFI analysis of hydrogen market formation in the United States; the directions that companies are pursuing in hydrogen production transport and storage and end use at this early stage of value chain development will inform subsequent analysis in important ways.
Scientific Assessment in Support of the Materials Roadmap enabling Low Carbon Energy Technologies Hydrogen and Fuel Cells
Apr 2014
Publication
A group experts from European research organisations and industry have assessed the state of the art and future needs for materials' R&D for hydrogen and fuel cell technologies. The work was performed as input to the European Commission's roadmapping exercise on materials for the European Strategic Energy Technology Plan. The report summarises the results including key targets identified for medium term (2020/2030) and long term (2050) timescales.
Evaluation of Stability and Catalytic Activity of Ni Catalysts for Hydrogen Production by Biomass Gasification in Supercritical Water
Mar 2019
Publication
Supercritical water gasification is a promising technology for wet biomass utilization. In this paper Ni and other metal catalysts were synthesized by wet impregnation. The stability and catalytic activities of Ni catalysts were evaluated. Firstly catalytic activities of Ni Fe Cu catalysts supported on MgO were tested using wheat straw as raw material in a batch reactor at 723 K and water density of 0.07 cm3/g. Experimental results showed that the order of metal catalyst activity for hydrogen generation was Ni/MgO > Fe/MgO > Cu/MgO. Secondly the influence of different supports on Ni catalysts performance was investigated. The results showed that the order of the Ni catalysts’ activity with different supports was Ni/MgO > Ni/ZnO > Ni/Al2O3 > Ni/ZrO2. Finally the effects of Ni loading and the amount of Ni catalyst addition on hydrogen production and the stability of Ni/MgO catalyst were studied. It was found that serious deactivation of Ni catalyst in the process of supercritical water gasification took place. Even if carbon deposited on the catalyst surface was removed by high temperature calcination and the catalyst was reduced with hydrogen the activity of used catalyst was only partially restored.
Thermal Management System Architecture for Hydrogen-Powered Propulsion Technologies: Practices, Thematic Clusters, System Architectures, Future Challenges, and Opportunities
Jan 2022
Publication
The thermal management system architectures proposed for hydrogen-powered propulsion technologies are critically reviewed and assessed. The objectives of this paper are to determine the system-level shortcomings and to recognise the remaining challenges and research questions that need to be sorted out in order to enable this disruptive technology to be utilised by propulsion system manufacturers. Initially a scientometrics based co-word analysis is conducted to identify the milestones for the literature review as well as to illustrate the connections between relevant ideas by considering the patterns of co-occurrence of words. Then a historical review of the proposed embodiments and concepts dating back to 1995 is followed. Next feasible thermal management system architectures are classified into three distinct classes and its components are discussed. These architectures are further extended and adapted for the application of hydrogen-powered fuel cells in aviation. This climaxes with the assessment of the available evidence to verify the reasons why no hydrogen-powered propulsion thermal management system architecture has yet been approved for commercial production. Finally the remaining research challenges are identified through a systematic examination of the critical areas in thermal management systems for application to hydrogen-powered air vehicles’ engine cooling. The proposed solutions are discussed from weight cost complexity and impact points of view by a system-level assessment of the critical areas in the field.
A Novel Remaining Useful Life Prediction Method for Hydrogen Fuel Cells Based on the Gated Recurrent Unit Neural Network
Jan 2022
Publication
The remaining useful life (RUL) prediction for hydrogen fuel cells is an important part of its prognostics and health management (PHM). Artificial neural networks (ANNs) are proven to be very effective in RUL prediction as they do not need to understand the failure mechanisms behind hydrogen fuel cells. A novel RUL prediction method for hydrogen fuel cells based on the gated recurrent unit ANN is proposed in this paper. Firstly the data were preprocessed to remove outliers and noises. Secondly the performance of different neural networks is compared including the back propagation neural network (BPNN) the long short-term memory (LSTM) network and the gated recurrent unit (GRU) network. According to our proposed method based on GRU the root mean square error was 0.0026 the mean absolute percentage error was 0.0038 and the coefficient of determination was 0.9891 for the data from the challenge datasets provided by FCLAB Research Federation when the prediction starting point was 650 h. Compared with the other RUL prediction methods based on the BPNN and the LSTM our prediction method is better in both prediction accuracy and convergence rate.
New Combustion Modelling Approach for Methane-Hydrogen Fueled Engines Using Machine Learning and Engine Virtualization
Oct 2021
Publication
The achievement of a carbon-free emissions economy is one of the main goals to reduce climate change and its negative effects. Scientists and technological improvements have followed this trend improving efficiency and reducing carbon and other compounds that foment climate change. Since the main contributor of these emissions is transportation detaching this sector from fossil fuels is a necessary step towards an environmentally friendly future. Therefore an evaluation of alternative fuels will be needed to find a suitable replacement for traditional fossil-based fuels. In this scenario hydrogen appears as a possible solution. However the existence of the drawbacks associated with the application of H2 -ICE redirects the solution to dual-fuel strategies which consist of mixing different fuels to reduce negative aspects of their separate use while enhancing the benefits. In this work a new combustion modelling approach based on machine learning (ML) modeling is proposed for predicting the burning rate of different mixtures of methane (CH4 ) and hydrogen (H2). Laminar flame speed calculations have been performed to train the ML model finding a faster way to obtain good results in comparison with actual models applied to SI engines in the virtual engine model framework.
Building Efficiency- Reducing Energy Demand in the Commercial Sector
Dec 2013
Publication
The report was formally launched on 2nd December in Parliament at a panel debate chaired by Lord Whitty and Oliver Colvile and featured representatives from Government and Industry. The report outlines the case for investment by businesses in the energy efficiency of their buildings and operations and highlights how this could help neutralise the threat to profitability posed by increasing energy bills energy price volatility and an increasing reliance on electricity in the commercial sector. The report highlights that business in the UK have the opportunity to not only reduce energy bills but increase their competitiveness and improve worker productivity through better designed buildings.
Optimising Air Quality Co-benefits in a Hydrogen Economy: A Case for Hydrogen-specific Standards for NOx Emissions
Jun 2021
Publication
A global transition to hydrogen fuel offers major opportunities to decarbonise a range of different energyintensive sectors from large-scale electricity generation through to heating in homes. Hydrogen can be deployed as an energy source in two distinct ways in electrochemical fuel cells and via combustion. Combustion seems likely to be a major pathway given that it requires only incremental technological change. The use of hydrogen is not however without side-effects and the widely claimed benefit that only water is released as a by-product is only accurate when it is used in fuel cells. The burning of hydrogen can lead to the thermal formation of nitrogen oxides (NOx – the sum of NO + NO2) via a mechanism that also applies to the combustion of fossil fuels. NO2 is a key air pollutant that is harmful in its own right and is a precursor to other pollutants of concern such as fine particulate matter and ozone. Minimising NOx as a by-product from hydrogen boilers and engines is possible through control of combustion conditions but this can lead to reduced power output and performance. After-treatment and removal of NOx is possible but this increases cost and complexity in appliances. Combustion applications therefore require optimisation and potentially lower hydrogen-specific emissions standards if the greatest air quality benefits are to derive from a growth in hydrogen use
Porosity and Thickness Effect of Pd–Cu–Si Metallic Glasses on Electrocatalytic Hydrogen Production and Storage
Aug 2021
Publication
This contribution places emphasis on tuning pore architecture and film thickness of mesoporous Pd–Cu–Si thin films sputtered on Si/SiO2 substrates for enhanced electrocatalytic and hydrogen sorption/desorption activity and their comparison with the state-of-the-art thin film electrocatalysts. Small Tafel slope of 43 mV dec–1 for 1250 nm thick coatings with 2 µm diameter pores with 4.2 µm interspacing (H2) electrocatalyst with comparable hydrogen overpotentials to the literature suggests its use for standard fuel cells. The largest hydrogen sorption has been attained for the 250 nm thick electrocatalyst on 5 µm pore diameter and 12 µm interspacing (2189 µC cm–2 per CV cycle) making it possible for rapid storage systems. Moreover the charge transfer resistance described by an equivalent circuit model has an excellent correlation with Tafel slopes. Along with its very low Tafel slope of 42 mV dec–1 10 nm thick H2 pore design electrocatalyst has the highest capacitive response of ∼0.001 S sn cm–2 and is promising to be used as a nano-charger and hydrogen sensor.
Fundamentals, Materials, and Machine Learning of Polymer Electrolyte Membrane Fuel Cell Technology
Jun 2020
Publication
Polymer electrolyte membrane (PEM) fuel cells are electrochemical devices that directly convert the chemical energy stored in fuel into electrical energy with a practical conversion efficiency as high as 65%. In the past years significant progress has been made in PEM fuel cell commercialization. By 2019 there were over 19000 fuel cell electric vehicles (FCEV) and 340 hydrogen refueling stations (HRF) in the U.S. (~8000 and 44 respectively) Japan (~3600 and 112 respectively) South Korea (~5000 and 34 respectively) Europe (~2500 and 140 respectively) and China (~110 and 12 respectively). Japan South Korea and China plan to build approximately 3000 HRF stations by 2030. In 2019 Hyundai Nexo and Toyota Mirai accounted for approximately 63% and 32% of the total sales with a driving range of 380 and 312 miles and a mile per gallon (MPGe) of 65 and 67 respectively. Fundamentals of PEM fuel cells play a crucial role in the technological advancement to improve fuel cell performance/durability and reduce cost. Several key aspects for fuel cell design operational control and material development such as durability electrocatalyst materials water and thermal management dynamic operation and cold start are briefly explained in this work. Machine learning and artificial intelligence (AI) have received increasing attention in material/energy development. This review also discusses their applications and potential in the development of fundamental knowledge and correlations material selection and improvement cell design and optimization system control power management and monitoring of operation health for PEM fuel cells along with main physics in PEM fuel cells for physics-informed machine learning. The objective of this review is three fold: (1) to present the most recent status of PEM fuel cell applications in the portable stationary and transportation sectors; (2) to describe the important fundamentals for the further advancement of fuel cell technology in terms of design and control optimization cost reduction and durability improvement; and (3) to explain machine learning physics-informed deep learning and AI methods and describe their significant potentials in PEM fuel cell research and development (R&D).
Evaluation of Zero-Energy Building and Use of Renewable Energy in Renovated Buildings: A Case Study in Japan
Apr 2022
Publication
Following the Paris Agreement in 2015 the worldwide focus on global warming countermeasures has intensified. The Japanese government has declared its aim at achieving carbon neutrality by 2050. The concept of zero-energy buildings (ZEBs) is based on measures to reduce energy consumption in buildings the prospects of which are gradually increasing. This study investigated the annual primary energy consumption; as well as evaluated renewed and renovated buildings that had a solar power generation system and utilized solar and geothermal heat. It further examines the prospects of hydrogen production from on-site surplus electricity and the use of hydrogen fuel cells. A considerable difference was observed between the actual energy consumption (213 MJ/m2 ) and the energy consumption estimated using an energy simulation program (386 MJ/m2 ). Considerable savings of energy were achieved when evaluated based on the actual annual primary energy consumption of a building. The building attained a near net zero-energy consumption considering the power generated from the photovoltaic system. The study showed potential energy savings in the building by producing hydrogen using surplus electricity from on-site power generation and introducing hydrogen fuel cells. It is projected that a building’s energy consumption will be lowered by employing the electricity generated by the hydrogen fuel cell for standby power water heating and regenerating heat from the desiccant system.
Thermodynamic Analysis of Solid Oxide Electrolyzer Integration with Engine Waste Heat Recovery for Hydrogen Production
Jul 2021
Publication
Water electrolysis based on solid oxide electrolysis cell (SOEC) exhibits high conversion efficiency due to part of energy demand can be derived from thermal energy. Therefore it can be integrated with other sources of thermal energy to reduce the consumption of electrical energy. In this paper a diesel engine is integrated with the SOEC stacks for heat recovery steam generator (HRSG). The thermal energy from the engine exhaust gas used to heat the inlet H2O of the SOEC is carried out as the integration case. A SOEC plant using electricity as the thermal heat input is selected as the base case. Thermodynamic analysis of the benchmark and integration scheme reveals that an electrical efficiency of 73.12% and 85.17% can be achieved respectively. The diesel to power efficiency can be increased to 70% when the exhaust gas is completely utilized by the SOEC system. The impacts of some key parameters including current density and operating temperature on system performance have also been conducted and found that the system has optimized parameters of current density and operating temperature to achieve better performance.
Hydrogen vs. Batteries: Comparative Safety Assessments for a High-Speed Passenger Ferry
Mar 2022
Publication
Batteries and hydrogen constitute two of the most promising solutions for decarbonising international shipping. This paper presents the comparison between a battery and a proton-exchange membrane hydrogen fuel cell version of a high-speed catamaran ferry with a main focus on safety. The systems required for each version are properly sized and fitted according to the applicable rules and their impact on the overall design is discussed. Hazards for both designs were identified; frequency and consequence indexes for them were input qualitatively following Novel Technology Qualification and SOLAS Alternative Designs and Arrangements while certain risk control options were proposed in order to reduce the risks of the most concerned accidental events. The highest ranked risks were analysed by quantitative risk assessments in PyroSim software. The gas dispersion analysis performed for the hydrogen version indicated that it is crucial for the leakage in the fuel cell room to be stopped within 1 s after being detected to prevent the formation of explosive masses under full pipe rupture of 33 mm diameter even with 120 air changes per hour. For the battery version the smoke/fire simulation in the battery room indicated that the firefighting system could achieve a 30% reduction in fire duration with firedoors closed and ventilation shut compared to the scenario without a firefighting system.
Opportunities for Low-carbon Generation and Storage Technologies to Decarbonise the Future Power System
Feb 2023
Publication
Alternatives to cope with the challenges of high shares of renewable electricity in power systems have been addressed from different approaches such as energy storage and low-carbon technologies. However no model has previously considered integrating these technologies under stability requirements and different climate conditions. In this study we include this approach to analyse the role of new technologies to decarbonise the power system. The Spanish power system is modelled to provide insights for future applications in other regions. After including storage and low-carbon technologies (currently available and under development) batteries and hydrogen fuel cells have low penetration and the derived emission reduction is negligible in all scenarios. Compressed air storage would have a limited role in the short term but its performance improves in the long term. Flexible generation technologies based on hydrogen turbines and long-duration storage would allow the greatest decarbonisation providing stability and covering up to 11–14 % of demand in the short and long term. The hydrogen storage requirement is equivalent to 18 days of average demand (well below the theoretical storage potential in the region). When these solutions are considered decarbonising the electricity system (achieving Paris targets) is possible without a significant increase in system costs (< € 114/MWh).
Boosting the H2 Production Efficiency via Photocatalytic Organic Reforming: The Role of Additional Hole Scavenging System
Nov 2021
Publication
The simultaneous photocatalytic H2 evolution with environmental remediation over semiconducting metal oxides is a fascinating process for sustainable fuel production. However most of the previously reported photocatalytic reforming showed nonstoichiometric amounts of the evolved H2 when organic substrates were used. To explain the reasons for this phenomenon a careful analysis of the products and intermediates in gas and aqueous phases upon the photocatalytic hydrogen evolution from oxalic acid using Pt/TiO2 was performed. A quadrupole mass spectrometer (QMS) was used for the continuous flow monitoring of the evolved gases while high performance ion chromatography (HPIC) isotopic labeling and electron paramagnetic resonance (EPR) were employed to understand the reactions in the solution. The entire consumption of oxalic acid led to a ~30% lower H2 amount than theoretically expected. Due to the contribution of the photoKolbe reaction mechanism a tiny amount of formic acid was produced then disappeared shortly after the complete consumption of oxalic acid. Nevertheless a much lower concentration of formic acid was generated compared to the nonstoichiometric difference between the formed H2 and the consumed oxalic acid. Isotopic labeling measurements showed that the evolved H2 HD and/or D2 matched those of the solvent; however using D2O decreased the reaction rate. Interestingly the presence of KI as an additional hole scavenger with oxalic acid had a considerable impact on the reaction mechanism and thus the hydrogen yield as indicated by the QMS and the EPR measurements. The added KI promoted H2 evolution to reach the theoretically predictable amount and inhibited the formation of intermediates without affecting the oxalic acid degradation rate. The proposed mechanism by which KI boosts the photocatalytic performance is of great importance in enhancing the overall energy efficiency for hydrogen production via photocatalytic organic reforming.
Optimal Energy Management in a Standalone Microgrid, with Photovoltaic Generation, Short-Term Storage, and Hydrogen Production
Mar 2020
Publication
This paper addresses the energy management of a standalone renewable energy system. The system is configured as a microgrid including photovoltaic generation a lead-acid battery as a short term energy storage system hydrogen production and several loads. In this microgrid an energy management strategy has been incorporated that pursues several objectives. On the one hand it aims to minimize the amount of energy cycled in the battery in order to reduce the associated losses and battery size. On the other hand it seeks to take advantage of the long-term surplus energy producing hydrogen and extracting it from the system to be used in a fuel cell hybrid electric vehicle. A crucial factor in this approach is to accommodate the energy consumption to the energy demand and to achieve this a model predictive control (MPC) scheme is proposed. In this context proper models for solar estimation hydrogen production and battery energy storage will be presented. Moreover the controller is capable of advancing or delaying the deferrable loads from its prescheduled time. As a result a stable and efficient supply with a relatively small battery is obtained. Finally the proposed control scheme has been validated on a real case scenario.
Energy Storage Systems: A Review
Jul 2022
Publication
The world is rapidly adopting renewable energy alternatives at a remarkable rate to address the ever-increasing environmental crisis of CO2 emissions. Renewable Energy Systems (RES) offers enormous potential to decarbonize the environment because they produce no greenhouse gases or other polluting emissions. However the RES relies on natural resources for energy generation such as sunlight wind water geothermal which are generally unpredictable and reliant on weather season and year. To account for these intermittencies renewable energy can be stored using various techniques and then used in a consistent and controlled manner as needed. Several researchers from around the world have made substantial contributions over the last century to developing novel methods of energy storage that are efficient enough to meet increasing energy demand and technological break-throughs. This review attempts to provide a critical review of the advancements in the Energy Storage System (ESS) from 1850–2022 including its evolution classification operating principles and comparison
Study of Heat Loss Mechanism in Argon-circulated Hydrogen Engine Combustion Chamber Wall Surface Conditions
Jul 2022
Publication
Hydrogen fuel in internal combustion engine gives a very big advantage to the transportation sector especially in solving the greenhouse emission problem. However there are only few research discovered the ability of argon as a working gas in hydrogen combustion in internal combustion engine. The high temperature rises from the argon compression tend to result in heat loss problem. This research aims to study the heat loss mechanism on wall surface condition in the combustion chamber. Experiments were conducted to study the effects of different heat flux sensor locations and the effect of ignition delay on heat flux. Local heat flux measurement was collected and images were observed using high speed shadowgraph images. The ignition delay that occurred near the combustion wall will result in larger heat loss throughout the combustion process. Higher ambient pressure results in a bigger amount of heat flux value. Other fundamental characteristics were obtained and discussed which may help in contributing the local heat loss data of an argon-circulated hydrogen engine in future engine operation.
Impacts of Greenhouse Gas Neutrality Strategies on Gas Infrastructure and Costs: Implications from Case Studies Based on French and German GHG-neutral Scenarios
Sep 2022
Publication
The European Union’s target to reach greenhouse gas neutrality by 2050 calls for a sharp decrease in the consumption of natural gas. This study assesses impacts of greenhouse gas neutrality on the gas system taking France and Germany as two case studies which illustrate a wide range of potential developments within the European Union. Based on a review of French and German GHG-neutral scenarios it explores impacts on gas infrastructure and estimates the changes in end-user methane price considering a business-as-usual and an optimised infrastructure pathway. Our results show that gas supply and demand radically change by mid-century across various scenarios. Moreover the analysis suggests that deep transformations of the gas infrastructure are required and that according to the existing pricing mechanisms the end-user price of methane will increase driven by the switch to low-carbon gases and intensified by infrastructure costs.
Hydrogen-powered Aviation: A Fact-based Study of Hydrogen Technology, Economics, and Climate Impact by 2050
Jul 2020
Publication
This report assesses the potential of hydrogen (H2) propulsion to reduce aviation’s climate impact. To reduce climate impact the industry will have to introduce further levers such as radically new technology significantly scale sustainable aviation fuels (SAF) such as synthetic fuel (synfuel) temporarily rely on offsets in large quantities or rely on a combination thereof. H2 propulsion is one such technology and this report assesses its potential in aviation. Developed with input from leading companies and research institutes it projects the technological development of H2 combustion and fuel cell-powered propulsion evaluates their technical and economic feasibility compares them to synfuel and considers implications on aircraft design airport infrastructure and fuel supply chains.
Numerical Study of Combustion and Emission Characteristics for Hydrogen Mixed Fuel in the Methane-Fueled Gas Turbine Combustor
Jan 2023
Publication
The aeroderivative gas turbine is widely used as it demonstrates many advantages. Adding hydrogen to natural gas fuels can improve the performance of combustion. Following this the effects of hydrogen enrichment on combustion characteristics were analyzed in an aeroderivative gas turbine combustor using CFD simulations. The numerical model was validated with experimental results. The conditions of the constant mass flow rate and the constant energy input were studied. The results indicate that adding hydrogen reduced the fuel residues significantly (fuel mass at the combustion chamber outlet was reduced up to 60.9%). In addition the discharge of C2H2 and other pollutants was reduced. Increasing the volume fraction of hydrogen in the fuel also reduced CO emissions at the constant energy input while increasing CO emissions at the constant fuel mass flow rate. An excess in the volume fraction of added hydrogen changed the combustion mode in the combustion chamber resulting in fuel-rich combustion (at constant mass flow rate) and diffusion combustion (at constant input power). Hydrogen addition increased the pattern factor and NOx emissions at the outlet of the combustion chamber.
Going Offshore or Not: Where to Generate Hydrogen in Future Integrated Energy Systems?
Jan 2023
Publication
Hydrogen can be key in the energy system transition. We investigate the role of offshore hydrogen generation in a future integrated energy system. By performing energy system optimisation in a model application of the Northern-central European energy system and the North Sea offshore grid towards 2050 we find that offshore hydrogen generation may likely only play a limited role and that offshore wind energy has higher value when sent to shore in the form of electricity. Forcing all hydrogen generation offshore would lead to increased energy system costs. Under the assumed scenario conditions which result in deep decarbonisation of the energy system towards 2050 hydrogen generation – both onshore and offshore – follows solar PV generation patterns. Combined with hydrogen storage this is the most cost-effective solution to satisfy future hydrogen demand. Overall we find that the role of future offshore hydrogen generation should not simply be derived from minimising costs for the offshore sub-system but by also considering the economic value that such generation would create for the whole integrated energy system. We find as a no-regret option to enable and promote the integration of offshore wind in onshore energy markets via electrical connections.
Hydrogen-powered Aviation in Germany: A Macroeconomic Perspective and Methodological Approach of Fuel Supply Chain Integration into an Economy-wide Dataset
Oct 2022
Publication
The hydrogen (H2) momentum affects the aviation sector. However a macroeconomic consideration is currently missing. To address this research gap the paper derives a methodology for evaluating macroeconomic effects of H2 in aviation and applies this approach to Germany. Three goals are addressed: (1) Construction of a German macroeconomic database. (2) Translation of H2 supply chains to the system of national accounts. (3) Implementation of H2-powered aviation into the macroeconomic data framework. The article presents an economy-wide database for analyzing H2-powered aviation. Subsequently the paper highlights three H2 supply pathways provides an exemplary techno-economic cost break-down for ten H2 components and translates them into the data framework. Eight relevant macroeconomic sectors for H2-powered aviation are identified and quantified. Overall the paper contributes on a suitable foundation to apply the macroeconomic dataset to and conduct macroeconomic analyses on H2-powered aviation. Finally the article highlights further research potential on job effects related to future H2 demand.
Hydrogen Refueling Stations and Carbon Emission Reduction of Coastal Expressways: A Deployment Model and Multi-Scenario Analysis
Jul 2022
Publication
Hydrogen is considered to the ultimate solution to achieve carbon emission reduction due to its wide sources and high calorific value as well as non-polluting renewable and storable advantages. This paper starts from the coastal areas uses offshore wind power hydrogen production as the hydrogen source and focuses on the combination of hydrogen supply chain network design and hydrogen expressway hydrogen refueling station layout optimization. It proposes a comprehensive mathematical model of hydrogen supply chain network based on cost analysis which determined the optimal size and location of hydrogen refueling stations on hydrogen expressways in coastal areas. Under the multi-scenario and multi-case optimization results the location of the hydrogen refueling station can effectively cover the road sections of each case and the unit hydrogen cost of the hydrogen supply chain network is between 11.8 and 15.0 USD/kgH2 . Meanwhile it was found that the transportation distance and the number of hydrogen sources play a decisive role on the cost of hydrogen in the supply chain network and the location of hydrogen sources have a decisive influence on the location of hydrogen refueling stations. In addition carbon emission reduction results of hydrogen supply chain network show that the carbon emission reduction per unit hydrogen production is 15.51 kgCO2/kgH2 at the production side. The CO2 emission can be reduced by 68.3 kgCO2/km and 6.35 kgCO2/kgH2 per unit mileage and per unit hydrogen demand at the application side respectively. The layout planning utilization of hydrogen energy expressway has a positive impact on energy saving and emission reduction.
A Recent Review of Primary Hydrogen Carriers, Hydrogen Production Methods, and Applications
Mar 2023
Publication
Hydrogen is a promising energy carrier especially for transportation owing to its unique physical and chemical properties. Moreover the combustion of hydrogen gas generates only pure water; thus its wide utilization can positively affect human society to achieve global net zero CO2 emissions by 2050. This review summarizes the characteristics of the primary hydrogen carriers such as water methane methanol ammonia and formic acid and their corresponding hydrogen production methods. Additionally state-of-the-art studies and hydrogen energy applications in recent years are also included in this review. In addition in the conclusion section we summarize the advantages and disadvantages of hydrogen carriers and hydrogen production techniques and suggest the challenging tasks for future research.
Cost Benefit Analysis for Green Hydrogen Production from Treated Effluent: The Case Study of Oman
Nov 2022
Publication
Recently the management of water and wastewater is gaining attention worldwide as a way of conserving the natural resources on the planet. The traditional wastewater treatment in Oman is such that the treated effluent produced is only reused for unfeasible purposes such as landscape irrigation cooling or disposed of in the sea. Introducing more progressive reuse applications can result in achieving a circular economy by considering treated effluent as a source of producing new products. Accordingly wastewater treatment plants can provide feedstock for green hydrogen production processes. The involvement of the wastewater industry in the green pathway of production scores major points in achieving decarbonization. In this paper the technical and economic feasibility of green hydrogen production in Oman was carried out using a new technique that would help explore the benefits of the treated effluent from wastewater treatment in Oman. The feasibility study was conducted using the Al Ansab sewage treatment plant in the governate of Muscat in Wilayat (region) Bousher. The results have shown that the revenue from Al Ansab STP in a conventional case is 7.02 million OMR/year while sustainable alternatives to produce hydrogen from the Proton Exchange Membrane (PEM) electrolyzer system for two cases with capacities of 1500 kg H2/day and 50000 kg H2/day would produce revenue of 8.30 million OMR/year and 49.73 million OMR/year respectively.
Impact of Hydrogen/Natural Gas Blends on Partially Premixed Combustion Equipment: NOx Emission and Operational Performance
Feb 2022
Publication
Several North American utilities are planning to blend hydrogen into gas grids as a short‐ term way of addressing the scalable demand for hydrogen and as a long‐term decarbonization strat‐ egy for ‘difficult‐to‐electrify’ end uses. This study documents the impact of 0–30% hydrogen blends by volume on the performance emissions and safety of unadjusted equipment in a simulated use environment focusing on prevalent partially premixed combustion designs. Following a thorough literature review the authors describe three sets of results: operating standard and “ultra‐low NOx” burners from common heating equipment in “simulators” with hydrogen/methane blends up to 30% by volume in situ testing of the same heating equipment and field sampling of a wider range of equipment with 0–10% hydrogen/natural gas blends at a utility‐owned training facility. The equipment was successfully operated with up to 30% hydrogen‐blended fuels with limited visual changes to flames and key trends emerged: (a) a decrease in the input rate from 0 to 30% H2 up to 11% often in excess of the Wobbe Index‐based predictions; (b) NOx and CO emissions are flat or decline (air‐free or energy‐adjusted basis) with increasing hydrogen blending; and (c) a minor de‐ crease (1.2%) or increase (0.9%) in efficiency from 0 to 30% hydrogen blends for standard versus ultra‐low NOx‐type water heaters respectively.
Hydrogen Production from Sea Wave for Alternative Energy Vehicles for Public Transport in Trapani (Italy)
Oct 2016
Publication
The coupling of renewable energy and hydrogen technologies represents in the mid-term a very interesting way to match the tasks of increasing the reliable exploitation of wind and sea wave energy and introducing clean technologies in the transportation sector. This paper presents two different feasibility studies: the first proposes two plants based on wind and sea wave resource for the production storage and distribution of hydrogen for public transportation facilities in the West Sicily; the second applies the same approach to Pantelleria (a smaller island) including also some indications about solar resource. In both cases all buses will be equipped with fuel-cells. A first economic analysis is presented together with the assessment of the avoidable greenhouse gas emissions during the operation phase. The scenarios addressed permit to correlate the demand of urban transport to renewable resources present in the territories and to the modern technologies available for the production of hydrogen from renewable energies. The study focuses on the possibility of tapping the renewable energy potential (wind and sea wave) for the hydrogen production by electrolysis. The use of hydrogen would significantly reduce emissions of particulate matter and greenhouse gases in urban districts under analysis. The procedures applied in the present article as well as the main equations used are the result of previous applications made in different technical fields that show a good replicability.
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