Publications
Hydrogen Impacts on Downstream Installation and Appliances
Nov 2019
Publication
The report analyses the technical impacts to end-users of natural gas in Australian distribution networks when up to 10% hydrogen (by volume) is mixed with natural gas.
The full report can be found at this link.
The full report can be found at this link.
Impact of Hydrogen Admixture on Combustion Processes – Part II: Practice
Dec 2020
Publication
The Fuel Cells & Hydrogen Joint Undertaking (FCH JU) project ""Testing Hydrogen admixture for Gas Appliances"" aka THyGA is proud to release the second deliverable about the impact of hydrogen admixture on combustion processes. This time the report explores the expected impact of H2NG on a range of appliance designs installed in the EU.
After the deliverable D2.2 dedicated to the theorical estimation of the impact of H2 admixture THyGA reviews results from the litterature to evaluate available knowledge on CO and NOx formation overheating flame temperature flashback H2 leakage operational implications and efficiency of appliances supplied with H2NG blends. Learn more and read deliverable D2.3.
Climate change is one of today’s most pressing global challenges. Since the emission of greenhouse gases is often closely related to the use and supply of energy the goal to avoid emissions requires a fundamental restructuring of the energy system including all parts of the technology chains from production to end-use. Natural gas is today one of the most important primary energy sources in Europe with utilization ranging from power generation and industry to appliances in the residential and commercial sector as well as mobility. As natural gas is a fossil fuel gas utilization is thus responsible for significant emissions of carbon dioxide (CO2) a greenhouse gas.
This is part two. Part one of this project can be found at this link
After the deliverable D2.2 dedicated to the theorical estimation of the impact of H2 admixture THyGA reviews results from the litterature to evaluate available knowledge on CO and NOx formation overheating flame temperature flashback H2 leakage operational implications and efficiency of appliances supplied with H2NG blends. Learn more and read deliverable D2.3.
Climate change is one of today’s most pressing global challenges. Since the emission of greenhouse gases is often closely related to the use and supply of energy the goal to avoid emissions requires a fundamental restructuring of the energy system including all parts of the technology chains from production to end-use. Natural gas is today one of the most important primary energy sources in Europe with utilization ranging from power generation and industry to appliances in the residential and commercial sector as well as mobility. As natural gas is a fossil fuel gas utilization is thus responsible for significant emissions of carbon dioxide (CO2) a greenhouse gas.
This is part two. Part one of this project can be found at this link
Formation Criterion of Hydrogen-Induced Cracking in Steel Based on Fracture Mechanics
Nov 2018
Publication
A new criterion for hydrogen-induced cracking (HIC) that includes both the embrittlement effect and the loading effect of hydrogen was obtained theoretically. The surface cohesive energy and plastic deformation energy are reduced by hydrogen atoms at the interface; thus the fracture toughness is reduced according to fracture mechanics theory. Both the pressure effect and the embrittlement effect mitigate the critical condition required for crack instability extension. During the crack instability expansion the hydrogen in the material can be divided into two categories: hydrogen atoms surrounding the crack and hydrogen molecules in the crack cavity. The loading effect of hydrogen was verified by experiments and the characterization methods for the stress intensity factor under hydrogen pressure in a linear elastic model and an elastoplastic model were analyzed using the finite-element simulation method. The hydrogen pressure due to the aggregation of hydrogen molecules inside the crack cavity regularly contributed to the stress intensity factor. The embrittlement of hydrogen was verified by electrolytic charging hydrogen experiments. According to the change in the atomic distribution during crack propagation in a molecular dynamics simulation the transition from ductile to brittle fracture and the reduction in the fracture toughness were due to the formation of crack tip dislocation regions suppressed by hydrogen. The HIC formation mechanism is both the driving force of crack propagation due to the hydrogen gas pressure and the resisting force reduced by hydrogen atoms.
Hy4Heat Hydrogen Colourant Report
May 2021
Publication
As part of Work Package 2 (WP2) of the Hy4Heat programme DNV produced a substantive report regarding colourant within a potential hydrogen gas network within the UK. Considering the advances within the hydrogen industry over the past year this covering document provides an update to the results as presented by DNV based on current industry progress and research.
The Hydrogen Colourant report was a study to determine if there is a requirement for adding a colourant to hydrogen to ensure that safe burning and user acceptance is achieved and to investigate the optimum solution if a colourant is required. The recommendation is that adding colourant to a future hydrogen gas network for use within buildings is not necessary if engineering measures are put in place to enable safe appliance operation."
- Advancements have been made in the understanding of key topics:
- Flame visibility and supervision
- Health and safety of colourant additives
- Production of Nitrogen Oxides (NOx)
- Likelihood of ignition from domestic electrical installations
- Nature of gas escapes
The Hydrogen Colourant report was a study to determine if there is a requirement for adding a colourant to hydrogen to ensure that safe burning and user acceptance is achieved and to investigate the optimum solution if a colourant is required. The recommendation is that adding colourant to a future hydrogen gas network for use within buildings is not necessary if engineering measures are put in place to enable safe appliance operation."
How Hydrogen Can Help Decarbonise the Maritime Sector
Jun 2021
Publication
Hydrogen Europe is the organisation representing the interests of the European hydrogen industry. It fully adheres to the European Union’s target of climate neutrality by 2050 and supports the European Commission’s objectives to develop and integrate more renewable energy sources into the European energy mix.<br/><br/>In December 2015 in Paris a global climate agreement was reached at the UN Climate Change Conference (COP 21). The Paris Agreement is seen as a historic and landmark instrument in climate action. However the agreement is lacking emphasis on international maritime transport and the role that this sector will need to play in contributing to the decarbonisation of the global economy and in striving for a clean planet for all.<br/><br/>Hydrogen hydrogen-based fuels (such as ammonia) and hydrogen technologies offer tremendous potential for the maritime sector<br/>and if properly harnessed can significantly contribute to the decarbonisation and also mitigate the air pollution of the worldwide fleet. Hydrogen Europe will be the catalyst in this process the decarbonisation and also mitigate the air pollution of the worldwide fleet. Hydrogen Europe will be the catalyst in this process.<br/><br/>The pathway towards hydrogen and hydrogenbased fuels for the maritime sector does not come without technological and commercial challenges let alone regulatory barriers.
Investigation on System for Renewable Electricity Storage in Small Scale Integrating Photovoltaics, Batteries, and Hydrogen Generator
Nov 2020
Publication
In this article the solution based on hydrogen generation to increase the flexibility of energy storage systems is proposed. Operating characteristics of a hydrogen generator with integrated electrical energy storage and a photovoltaic installation were determined. The key role of the electricity storage in the proposed system was to maintain the highest operating efficiency related to the nominal parameters of the hydrogen generator. The hydrogen generators achieved the highest energy efficiency for the nominal operating point at the highest power output. Lead-acid batteries were used to ensure the optimal operating conditions for the hydrogen generator supplied with renewable energy throughout the day. The proposed system reduces significantly the hydrogen generator nominal power and devices in system operate in such a way to improve their efficiency and durability. The relations between individual components and their constraints were determined. The proposed solution is fully in-line with previously investigated technologies for improving grid stability and can help incorporate renewable energy sources to increase the sustainability of the energy sector and green hydrogen production.
Towards Global Cleaner Energy and Hydrogen Production: A Review and Application ORC Integrality with Multigeneration Systems
Apr 2022
Publication
The current evidential effect of carbon emissions has become a societal challenge and the need to transition to cleaner energy sources/technologies has attracted wide research attention. Technologies that utilize low-grade heat like the organic Rankine cycle (ORC) and Kalina cycle have been proposed as viable approaches for fossil reduction/carbon mitigation. The development of renewable energy-based multigeneration systems is another alternative solution to this global challenge. Hence it is important to monitor the development of multigeneration energy systems based on low-grade heat. In this study a review of the ORC’s application in multigeneration systems is presented to highlight the recent development in ORC integrality/application. Beyond this a new ORC-CPVT (concentrated photovoltaic/thermal) integrated multigeneration system is also modeled and analyzed using the thermodynamics approach. Since most CPVT systems integrate hot water production in the thermal stem the proposed multigeneration system is designed to utilize part of the thermal energy to generate electricity and hydrogen. Although the CPVT system can achieve high energetic and exergetic efficiencies while producing thermal energy and electricity these efficiencies are 47.9% and 37.88% respectively for the CPVT-ORC multigeneration configuration. However it is noteworthy that the electricity generation from the CPVT-ORC configuration in this study is increased by 16%. In addition the hot water cooling effect and hydrogen generated from the multigeneration system are 0.4363 L/s 161 kW and 1.515 L/s respectively. The environmental analysis of the system also shows that the carbon emissions reduction potential is enormous.
Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project
Dec 2011
Publication
This report summarizes the work conducted under U.S. Department of Energy (DOE) under contract DE-FC36-04GO14285 by Mercedes-Benz & Research Development North America (MBRDNA) Chrysler Daimler Mercedes Benz USA (MBUSA) BP DTE Energy and NextEnergy to validate fuel cell technologies for infrastructure transportation as well as assess technology and commercial readiness for the market. The Mercedes Team together with its partners tested the technology by operating and fuelling hydrogen fuel cell vehicles under real world conditions in varying climate terrain and driving conditions. Vehicle and infrastructure data was collected to monitor the progress toward the hydrogen vehicle and infrastructure performance targets of $2.00 to 3.00/gge hydrogen production cost and 2000-hour fuel cell durability. Finally to prepare the public for a hydrogen economy outreach activities were designed to promote awareness and acceptance of hydrogen technology. DTE BP and NextEnergy established hydrogen filling stations using multiple technologies for on-site hydrogen generation storage and dispensing. DTE established a hydrogen station in Southfield Michigan while NextEnergy and BP worked together to construct one hydrogen station in Detroit. BP constructed another fueling station in Burbank California and provided a full-time hydrogen trailer at San Francisco California and a hydrogen station located at Los Angeles International Airportmore.
Prospecting Stress Formed by Hydrogen or Isotope Diffused in Palladium Alloy Cathode
Oct 2018
Publication
The objective of this project is to take into account the mechanical constraints formed by diffusion of hydrogen or tritium in watertight palladium alloy cathode. To know the origin of these it was necessary to discriminating the damaging effects encountered. Effectively hydrogen and isotope induce deformation embrittlement stress corrosion cracking and cathodic corrosion in different regions of cathode. Palladium can be alloyed with silver or yttrium to favourably increase diffusion and reduce these constraints. Effects of electrochemical factors temperature cathode structure adsorbed transient complex of palladium and porous material support are given to estimate and to limit possible damage.
Hydrogen to Support Electricity Systems
Jan 2020
Publication
The Department of Environment Land Water and Planning (DELWP) engaged GHD Advisory and ACIL Allen to assess the roles opportunities and challenges that hydrogen might play in the future to support Australia’s power systems and to determine whether the relevant electricity system regulatory frameworks are compatible with both enabling an industrial-scale1 hydrogen production capability and the use of hydrogen for power generation.
You can read the full report on the website of the Australian Government at this link
You can read the full report on the website of the Australian Government at this link
The Microstructure Study of the Hydrogenated Titanium Specimens Tested at High Temperature Creep for Long-term Tensile Strength
Feb 2020
Publication
Experimental tests of flat titanium samples at a temperature of 450 °C stretched with a constant force up to destruction were carried out. Titanium samples were hydrogenated in the Moscow Aviation Institute laboratory to a hydrogen content of 0.1 % 0.3 % and 0.6 % by weight of the specimen and then tested in the laboratory of Lomonosov Moscow State University. From the experiments the time to failure the localization time of the deformations and the stress distribution along the longitudinal coordinate of the sample over time were obtained. A metallographic study was conducted and the phase composition was investigated in Moscow Aviation Institute. The effect of hydrogen on long-term strength mechanical characteristics and phase composition has been elucidated.
A Techno-Economic Analysis of Solar Hydrogen Production by Electrolysis in the North of Chile and the Case of Exportation from Atacama Desert to Japan
Aug 2020
Publication
H2 production from solar electricity in the region of the Atacama Desert – Chile – has been identified as strategical for global hydrogen exportation. In this study the full supply chain of solar hydrogen has been investigated for 2018 and projected to scenarios for 2025-2030. Multi-year hourly electrical profiles data have been used from real operating PV plants and simulated Concentrated Solar Power “CSP” plants with Thermal Energy Storage “TES” as well as commercial electricity Power Purchase Agreement “PPA” prices reported in the Chilean electricity market were considered. The Levelized Cost of Hydrogen “LCOH” of each production pathway is calculated by a case-sensitive techno-economic MATLAB/Simulink model for utility scale (multi-MW) alkaline and PEM electrolyser technologies. Successively different distribution storage and transportation configurations are evaluated based on the 2025 Japanese case study according to the declared H2 demand. Transport in the form of liquefied hydrogen (LH2) and via ammonia (NH3) carrier is compared from the port of Antofagasta CL to the port of Osaka JP.
Evaluation of Decarbonization Technologies for ASEAN Countries via an Integrated Assessment Tool
May 2022
Publication
A new assessment tool for evaluating decarbonization technologies that considers each technology’s sustainability security affordability readiness and impact for a specific country is proposed. This tool is applied to a set of decarbonization technologies for the power transport and industry sectors for the ten Southeast Asian countries that constitute ASEAN. This results in a list of the most promising decarbonization technologies as well as the remaining issues that need more research and development. This study reveals several common themes for ASEAN’s decarbonization. First carbon capture and storage (CCS) is a key technology for large-scale CO2 emission. Second for countries that rely heavily on coal for power generation switching to gas can halve their CO2 emission in the power sector and should be given high priority. Third hydropower and bioenergy both have high potential for the majority of ASEAN countries if their sustainability issues can be resolved satisfactorily. Fourth replacing conventional vehicles by electric vehicles is the overarching theme in the road transport sector but will result in increased demand for electricity. In the medium to long term the use of hydrogen for marine fuel and biofuels for aviation fuel are preferred solutions for the marine and aviation transport sectors. Fifth for the industry sector installing CCS in industrial plants should be given priority but replacing fossil fuels by blue hydrogen for high-temperature heating is the preferred long-term solution.
Editorial—Special Issue “Catalysis for Energy Production”
Jun 2021
Publication
The rapid increase in anthropogenic greenhouse gas concentrations in the last several decades means that the effects of climate change are fast becoming the familiar horsemen of a planetary apocalypse. Catalysis one of the pillars of the chemical and petrochemical industries will play a critical role in the effort to reduce the flow of greenhouse gases into the atmosphere. This Special Issue is timely as it provides a collection of high-quality manuscripts in a diverse range of topics which include the production of green hydrogen via water electrolysis the steam reforming of ethanol propane or glycerol the dry reforming of methane and the autothermal reforming of diesel surrogate fuel. The topic of the transformation of biomass waste to chemicals is also well represented as is the tackling of CO2 emissions via novel utilization technologies. The Editors are grateful to all authors for their valuable contributions and confident that this Special Issue will prove valuable to scholars university professors and students alike.
Regulatory Mapping for Future Fuels
May 2020
Publication
Australia’s gas infrastructure is currently subject to regulations that were designed for a natural-gas only network system. Future Fuels CRC has released a full report and database of regulations to share exactly how Australia’s current gas regulations can be modernised to enable hydrogen biomethane and other potential future fuels.
This research thoroughly assessed Australia’s current regulatory framework to identify the regulations that will require modernisation to facilitate the use of future fuels within Australia’s energy networks and align them with the goals of Australia’s National Hydrogen Strategy. This study builds on the initial work completed as part of Australia’s National Hydrogen Strategy and creates a comprehensive regulatory map of relevant legislation across the natural gas production and supply chain which may be impacted by the addition of future fuels such as hydrogen and biomethane.
The research was delivered by RMIT University of Sydney and GPA Engineering supported by our industry and government participants APA APGA ATCO AusNet Services ENA Energy Safe Victoria Jemena and the South Australian Government.
The study’s report summarises the key issues and the direction of possible solutions. The study also created a database that holds details of legislation by state and territory as well as Commonwealth legislation and applicable Australian standards. The database is designed to be readily updated as these regulations continue to evolve.
The Australian energy industry and regulators benefit from this study by ensuring that any regulatory changes required for future fuels are identified early so that appropriate regulatory changes can be initiated and delivered. These changes will enable the many highly-regulated pilot projects happening across Australia to expand and develop under a modernised and effective regulatory environment.
You can find the full report on the Future Fuels CRC website here
This research thoroughly assessed Australia’s current regulatory framework to identify the regulations that will require modernisation to facilitate the use of future fuels within Australia’s energy networks and align them with the goals of Australia’s National Hydrogen Strategy. This study builds on the initial work completed as part of Australia’s National Hydrogen Strategy and creates a comprehensive regulatory map of relevant legislation across the natural gas production and supply chain which may be impacted by the addition of future fuels such as hydrogen and biomethane.
The research was delivered by RMIT University of Sydney and GPA Engineering supported by our industry and government participants APA APGA ATCO AusNet Services ENA Energy Safe Victoria Jemena and the South Australian Government.
The study’s report summarises the key issues and the direction of possible solutions. The study also created a database that holds details of legislation by state and territory as well as Commonwealth legislation and applicable Australian standards. The database is designed to be readily updated as these regulations continue to evolve.
The Australian energy industry and regulators benefit from this study by ensuring that any regulatory changes required for future fuels are identified early so that appropriate regulatory changes can be initiated and delivered. These changes will enable the many highly-regulated pilot projects happening across Australia to expand and develop under a modernised and effective regulatory environment.
You can find the full report on the Future Fuels CRC website here
Metastable Metal Hydrides for Hydrogen Storage
Oct 2012
Publication
The possibility of using hydrogen as a reliable energy carrier for both stationary and mobile applications has gained renewed interest in recent years due to improvements in high temperature fuel cells and a reduction in hydrogen production costs. However a number of challenges remain and new media are needed that are capable of safely storing hydrogen with high gravimetric and volumetric densities. Metal hydrides and complex metal hydrides offer some hope of overcoming these challenges; however many of the high capacity “reversible” hydrides exhibit a large endothermic decomposition enthalpy making it difficult to release the hydrogen at low temperatures. On the other hand the metastable hydrides are characterized by a low reaction enthalpy and a decomposition reaction that is thermodynamically favorable under ambient conditions. The rapid low temperature hydrogen evolution rates that can be achieved with these materials offer much promise for mobile PEM fuel cell applications. However a critical challenge exists to develop new methods to regenerate these hydrides directly from the reactants and hydrogen gas. This spotlight paper presents an overview of some of the metastable metal hydrides for hydrogen storage and a few new approaches being investigated to address the key challenges associated with these materials.
The Role of CCS in Meeting Climate Policy Targets
Oct 2017
Publication
Carbon capture and storage (CCS) refers to a set of technologies that may offer the potential for large-scale removal of CO2 emissions from a range of processes – potentially including the generation of electricity and heat industrial processes and the production of hydrogen and synthetic fuels. CCS has both proponents and opponents. Like other emerging low carbon technologies CCS is not without risks or uncertainties and there are various challenges that would need to be overcome if it were to be widely deployed. Policy makers’ decisions as to whether to pursue CCS should be based on a judgement as to whether the risks and uncertainties associated with attempting to deploy CCS outweigh the risks of not having it available as part of a portfolio of mitigation options in future years.
The full report can be found on the Global CSS Institute website at this link
The full report can be found on the Global CSS Institute website at this link
Biogas: Pathways to 2030
Mar 2021
Publication
Humans directly or indirectly generate over 105 billion tonnes of organic wastes globally each year all of which release harmful methane and other greenhouse gas emissions directly into the atmosphere as they decompose. These organic wastes include food waste sewage and garden wastes food and drink processing wastes and farm and agricultural wastes. Today only 2% of these are treated and recycled.
By simply managing these important bioresources more effectively we can cut global Greenhouse Gas (GHG) emissions by 10% by 2030. This report maps out how the global biogas industry can enable countries to deliver a 10% reduction in global GHG emissions by 2030. The pathways put humanity back on track to deliver by 2030 on the ambitions of both the Paris Agreement and UN Sustainable Development Goals (SDGs).
The report and the executive summary can be downloaded at this link
By simply managing these important bioresources more effectively we can cut global Greenhouse Gas (GHG) emissions by 10% by 2030. This report maps out how the global biogas industry can enable countries to deliver a 10% reduction in global GHG emissions by 2030. The pathways put humanity back on track to deliver by 2030 on the ambitions of both the Paris Agreement and UN Sustainable Development Goals (SDGs).
The report and the executive summary can be downloaded at this link
Effect of Cementite on the Hydrogen Diffusion/Trap Characteristics of 2.25Cr-1Mo-0.25V Steel with and without Annealing
May 2018
Publication
Hydrogen embrittlement (HE) is a critical issue that affects the reliability of hydrogenation reactors. The hydrogen diffusivity/trap characteristics of 2.25Cr-1Mo-0.25V steel are important parameters mainly used to study the HE mechanism of steel alloys. In this work the hydrogen diffusivity/trap characteristics of heat-treated (annealed) and untreated 2.25Cr-1Mo-0.25V steel were studied using an electrochemical permeation method. The microstructures of both 2.25Cr-1Mo-0.25V steels were investigated by metallurgical microscopy. The effect of cementite on the hydrogen diffusivity/trap mechanisms was studied using thermodynamics-based and Lennard–Jones potential theories. The results revealed that the cementite located at the grain boundaries and at the interfaces of lath ferrite served as a kind of hydrogen trap (i.e. an irreversible hydrogen trap). In addition hydrogen was transported from ferrite to cementite via up-hill diffusion thereby supporting the hypothesis of cementite acting as a hydrogen trap.
Hydrogen Assisted Macrodelamination in Gas Lateral Pipe
Jul 2016
Publication
Hydrogen assisted macrodelamination in the pipe elbows of 40-year exploited lateral pipelines located behind the compressor station was studied. The crack on the external surface of the pipe elbow was revealed. Macrodelamination was occurred in the steel being influenced by the joined action of working loads and hydrogen absorbed by metal during long-term operation. The causes of the material degradation were investigated by non-destructive testing using ultrasound thickness meter observing microstructure hydrostatic pressure testing and mechanical properties testing of pipe steel.<br/>Intensive degradation of steel primarily essential reduction of plasticity was revealed. The degradation degree of the pipe elbow steel was higher than of the straight pipe steel regardless of a section was tensioned or compressed. Basing on the tensile tests carried out on cylindrical smooth and notched specimens from the pipe elbow steel it was established that the plasticity of the damaged steel could be measured correctly only on the specimens with a circular notch due to concentration of deformation in the cross section location only. The limitations in using elongation and reduction in area for characterisation of plasticity of the pipe steel with extensive delamination were defined. The diagnostic features of macrodelamination namely an abnormal thickness meter readings and a sharp decrease in hardness and plasticity of the pipe elbow steel were established.
Physicochemical Properties of Proton-conducting SmNiO3 Epitaxial Films
Mar 2019
Publication
Proton conducting SmNiO3 (SNO) thin films were grown on (001) LaAlO3 substrates for systematically investigating the proton transport properties. X-ray Diffraction and Atomic Force Microscopy studies reveal that the as-grown SNO thin films have good single crystallinity and smooth surface morphology. The electrical conductivity measurements in air indicate a peak at 473 K in the temperature dependence of the resistance of the SNO films probably due to oxygen loss on heating. A Metal-Insulator-Transition occurs at 373 K for the films after annealing at 873 K in air. In a hydrogen atmosphere (3% H2/97% N2) an anomalous peak in the resistance is found at 685 K on the first heating cycle. Electrochemical Impedance Spectroscopy studies as a function of temperature indicate that the SNO films have a high ionic conductivity (0.030 S/cm at 773 K) in a hydrogen atmosphere. The activation energy for proton conductivity was determined to be 0.23 eV at 473–773 K and 0.37 eV at 773–973 K respectively. These findings demonstrate that SNO thin films have good proton conductivity and are good candidate electrolytes for low temperature proton-conducting Solid Oxide Fuel Cells.
Thermodynamic Analysis of a Regenerative Brayton Cycle Using H2, CH4 and H2/CH4 Blends as Fuel
Feb 2022
Publication
Considering a simple regenerative Brayton cycle the impact of using different fuel blends containing a variable volumetric percentage of hydrogen in methane was analysed. Due to the potential of hydrogen combustion in gas turbines to reduce the overall CO2 emissions and the dependency on natural gas further research is needed to understand the impact on the overall thermodynamic cycle. For that purpose a qualitative thermodynamic analysis was carried out to assess the exergetic and energetic efficiencies of the cycle as well as the irreversibilities associated to a subsystem. A single step reaction was considered in the hypothesis of complete combustion of a generic H2/CH4 mixture where the volumetric H2 percentage was represented by fH2 which was varied from 0 to 1 defining the amount of hydrogen in the fuel mixture. Energy and entropy balances were solved through the Engineering Equation Solver (EES) code. Results showed that global exergetic and energetic efficiencies increased by 5% and 2% respectively varying fH2 from 0 to 1. Higher hydrogen percentages resulted in lower exergy destruction in the chamber despite the higher air-excess levels. It was also observed that higher values of fH2 led to lower fuel mass flow rates in the chamber showing that hydrogen can still be competitive even though its cost per unit mass is twice that of natural gas.
Electrochemical and Stress Corrosion Mechanism of Submarine Pipeline in Simulated Seawater in Presence of Different Alternating Current Densities
Jun 2018
Publication
In this study electrochemical measurements immersion tests and slow strain rate tensile (SSRT) tests were applied to investigate the electrochemical and stress corrosion cracking (SCC) behavior of X70 steel in simulated seawater with the interference of different alternating current (AC) densities. The results indicate that AC significantly strengthens the cathodic reaction especially the oxygen reduction reaction. Simultaneously hydrogen evolution reaction occurs when the limiting diffusion current density of oxygen reaches and thus icorr sharply increases with the increase in AC density. Additionally when AC is imposed the X70 steel exhibits higher SCC susceptibility in the simulated seawater and the susceptibility increases with the increasing AC density. The SCC mechanism is controlled by both anodic dissolution (AD) and hydrogen embrittlement (HE) with the interference of AC.
Origin of the Catalytic Activity at Graphite Electrodes in Vanadium Flow Batteries
Jun 2021
Publication
For many electrochemical devices that use carbon-based materials such as electrolyzers supercapacitors and batteries oxygen functional groups (OFGs) are considered essential to facilitate electron transfer. Researchers implement surface-active OFGs to improve the electrocatalytic properties of graphite felt electrodes in vanadium flow batteries. Herein we show that graphitic defects and not OFGs are responsible for lowering the activation energy barrier and thus enhance the charge transfer properties. This is proven by a thermal deoxygenation procedure in which specific OFGs are removed before electrochemical cycling. The electronic and microstructural changes associated with deoxygenation are studied by quasi in situ X-ray photoelectron and Raman spectroscopy. The removal of oxygen groups at basal and edge planes improves the activity by introducing new active edge sites and carbon vacancies. OFGs hinder the charge transfer at the graphite–electrolyte interface. This is further proven by modifying the sp2 plane of graphite felt electrodes with oxygen-containing pyrene derivatives. The electrochemical evolution of OFGs and graphitic defects are studied during polarization and long-term cycling conditions. The hypothesis of increased activity caused by OFGs was refuted and hydrogenated graphitic edge sites were identified as the true reason for this increase.
Australian and Global Hydrogen Demand Growth Scenario Analysis
Nov 2019
Publication
Deloitte was commissioned by the National Hydrogen Taskforce established by the COAG Energy Council to undertake an Australian and Global Growth Scenario Analysis. Deloitte analysed the current global hydrogen industry its development and growth potential and how Australia can position itself to best capitalise on the newly forming industry.
To conceptualise the possibilities for Australia Deloitte created scenarios to model the realm of possibilities for Australia out to 2050 focusing on identifying the scope and distribution of economic and environmental costs and benefits from Australian hydrogen industry development. This work will aid in analysing the opportunities and challenges to hydrogen industry development in Australia and the actions needed to overcome barriers to industry growth manage risks and best drive industry development.
The full report is available on the Deloitte website at this link
To conceptualise the possibilities for Australia Deloitte created scenarios to model the realm of possibilities for Australia out to 2050 focusing on identifying the scope and distribution of economic and environmental costs and benefits from Australian hydrogen industry development. This work will aid in analysing the opportunities and challenges to hydrogen industry development in Australia and the actions needed to overcome barriers to industry growth manage risks and best drive industry development.
The full report is available on the Deloitte website at this link
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.
Study on Flake Formation Behavior and Its Influence Factors in Cr5 Steel
Apr 2018
Publication
A flake is a crack that is induced by trapped hydrogen within steel. To study its formation mechanism previous studies mostly focused on the formation process and magnitude of hydrogen pressure in hydrogen traps such as cavities and cracks. However according to recent studies the hydrogen leads to the decline of the mechanical properties of steel which is known as hydrogen embrittlement is another reason for flake formation. In addition the phenomenon of stress induced hydrogen uphill diffusion should not be neglected. All of the three behaviors are at work simultaneously. In order to further explore the formation mechanism of flakes in steel the process of flake initiation and growth were studied with the following three coupling factors: trap hydrogen pressure hydrogen embrittlement and stress induced hydrogen re-distribution. The analysis model was established using the finite element method and a crack whose radius is 0.5 mm was set in its center. The cohesive method and Bilinear Traction Separate Law (BTSL) were used to address the coupling effect. The results show that trap hydrogen pressure is the main driving force for flake formation. After the high hydrogen pressure was generated around the trap a stress field formed. In addition the trap is the center of stress concentration. Then hydrogen is concentrated in a distribution around this trap and most of the steel mechanical properties are reduced. The trap size is a key factor for defining the critical hydrogen content for flake formation and propagation. However when the trap size exceeds the specified value the critical hydrogen content does not change any more. As for the crack whose radius is 0.5 mm the critical hydrogen content of Cr5VMo steel is 2.2 ppm which is much closer to the maximum safe hydrogen concentration of 2.0 ppm used in China. The work presented in this article increases our understanding of flake formation and propagation mechanisms in steel.
Reliability of Liquid Organic Hydrogen Carrier-based Energy Storage in a Mobility Applications
Jan 2020
Publication
Liquid organic hydrogen carriers (LOHC) are a technology that allows storing hy-drogen in a safe and dense manner by reversible chemical conversion. They consti-tute a very promising option for energy storage transport and release combined withelectric power generation by fuel cells in large-scale applications like trains. In orderto establish trains running on LOHC it is mandatory to ensure the reliability of thesystem. This study evaluates various system configurations concerning reliabilityand resilience. The fault tree analysis method has been used to quantify the prob-ability of failure. The S-P matrix was applied to assess the different failure modes incontext of severity as well as their probability. The MTTF of the system can be morethan doubled by introducing single redundancy for the fuel cell and the reactor whilemore than two redundant components diminish the positive effect on reliability dueto higher complexity. It is estimated that the systems full functionality is available formore than 97% of its operating time.
Experimental and Numerical Study of Low Temperature Methane Steam Reforming for Hydrogen Production
Dec 2017
Publication
Low temperature methane steam reforming for hydrogen production using experimental developed Ni/Al2O3 catalysts is studied both experimentally and numerically. The catalytic activity measurements were performed at a temperature range of 500–700 ◦C with steam to carbon ratio (S/C) of 2 and 3 under atmospheric pressure conditions. A mathematical analysis to evaluate the reaction feasibility at all different conditions that have been applied by using chemical equilibrium with applications (CEA) software and in addition a mathematical model focused on the kinetics and the thermodynamics of the reforming reaction is introduced and applied using a commercial finite element analysis software (COMSOL Multiphysics 5.0). The experimental results were employed to validate the extracted simulation data based on the yields of the produced H2 CO2 and CO at different temperatures. A maximum hydrogen yield of 2.7 mol/mol-CH4 is achieved at 700 ◦C and S/C of 2 and 3. The stability of the 10%Ni/Al2O3 catalyst shows that the catalyst is prone to deactivation as supported by Thermogravimetric Analysis TGA results.
The Deltah Lab, a New Multidisciplinary European Facility to Support the H2 Distribution & Storage Economy
Apr 2021
Publication
The target for European decarburization encourages the use of renewable energy sources and H2 is considered the link in the global energy system transformation. So research studies are numerous but only few facilities can test materials and components for H2 storage. This work offers a brief review of H2 storage methods and presents the preliminary results obtained in a new facility. Slow strain rate and fatigue life tests were performed in H2 at 80 MPa on specimens and a tank of AISI 4145 respectively. Besides the storage capacity at 30 MPa of a solid-state system they were evaluated on kg scale by adsorption test. The results have shown the H2 influence on mechanical properties of the steel. The adsorption test showed a gain of 26% at 12 MPa in H2 storage with respect to the empty condition. All samples have been characterized by complementary techniques in order to connect the H2 effect with material properties.
Heat Pump Manufacturing Supply Chain Research Project Report
Dec 2020
Publication
The Department for Business Energy and Industrial Strategy (BEIS) commissioned a study to research the capacity of the manufacturing supply chain to meet expected future demand for heat pumps. This report contains analysis of the existing supply chain including component parts and also assesses the risks to and opportunities for growth in domestic heat pump manufacture and export.<br/><br/>Alongside a literature review the findings in this report were supported by interviews with organisations involved in the manufacture of heat pumps and an online workshop held with a range of businesses throughout the supply chain.
Failure Analysis of Cooling Duct of Top Engine Cowl Panel of Fighter Aircraft
Jun 2019
Publication
Present work describes the failure analysis of cooling duct of a fighter aircraft. The analyzed chemical composition of cooling duct indicates that it is manufactured from Al-based alloy (AA 3003 or its equivalent). Microstructure of cooling duct displays the presence of two phases namely matrix and insoluble particles. The hardness values at different locations within damaged area of cooling duct reflect nearly same and consistent. The fracture surface of the cooling duct exhibits transgranular features and cracks with little branching. The analyzed hydrogen content in cooling duct is significantly higher (∼ 12 ppm) than the specified one (< 1 ppm). However the alloy used to fabricate cooling duct is not susceptible to typical hydrogen embrittlement. This shows hydrogen pick up during operation. The presence of cracks with branching does reflect features of hydrogen embrittlement. In addition striations indicative of fatigue features are also observed. It thus appears that the cooling duct has failed due to pick up of large amount of hydrogen as well as vibrational fatigue.
Fractographic Features of Long Term Operated Gas Pipeline Steels Fracture Under Impact Loading
Jan 2020
Publication
Pipelines during their service life subjected to operational degradation i.e. their mechanical characteristics worsened with time. Pronounced texture of pipe steels associated with their manufacturing process revealed itself in an essential difference in impact toughness determined for specimens cut in mutually perpendicular directions with respect to the pipe axis. Higher KCV values for longitudinal specimens as compared with transverse ones were explained by the difference in a length of perlite grain strips separated by ferrite grains in specimens of different orientation. A role of hydrogen absorbed my metal during its operation in steel degradation was discussed.<br/>The main fractographic peculiarity for the operated steels comparing to the steels in the initial state is the appearance of delamination on the fracture surfaces which are oriented in the rolling direction. Correlation was found for the tested steels between fractographic sings of their embrittlement due to operational degradation and their loss of brittle fracture resistance. It is concluded that a decrease of impact toughness caused by long term operation of pipeline steels is definitely concerned with the amount of delamination on the fracture surfaces.
Integration of Hydrogen into Multi-Energy Systems Optimisation
Apr 2020
Publication
Hydrogen presents an attractive option to decarbonise the present energy system. Hydrogen can extend the usage of the existing gas infrastructure with low-cost energy storability and flexibility. Excess electricity generated by renewables can be converted into hydrogen. In this paper a novel multi-energy systems optimisation model was proposed to maximise investment and operating synergy in the electricity heating and transport sectors considering the integration of a hydrogen system to minimise the overall costs. The model considers two hydrogen production processes: (i) gas-to-gas (G2G) with carbon capture and storage (CCS) and (ii) power-to-gas (P2G). The proposed model was applied in a future Great Britain (GB) system. Through a comparison with the system without hydrogen the results showed that the G2G process could reduce £3.9 bn/year and that the P2G process could bring £2.1 bn/year in cost-savings under a 30 Mt carbon target. The results also demonstrate the system implications of the two hydrogen production processes on the investment and operation of other energy sectors. The G2G process can reduce the total power generation capacity from 71 GW to 53 GW and the P2G process can promote the integration of wind power from 83 GW to 130 GW under a 30 Mt carbon target. The results also demonstrate the changes in the heating strategies driven by the different hydrogen production processes.
Molybdenum Carbide Microcrystals: Efficient and Stable Catalyst for Photocatalytic H2 Evolution From Water in The Presence Of Dye Sensitizer
Sep 2016
Publication
Rod-like molybdenum carbide (Mo2C) microcrystals were obtained from the pyrolysis of Mo-containing organic-inorganic hybrid composite. We investigated the photocatalytic H2 evolution activity of Mo2C by constructing a Mo2C-dye sensitizer photocatalyst system. A high quantum efficiency of 29.7% was obtained at 480 nm. Moreover Mo2C catalyst can be easily recycled by simple filtration.
Combustion Characteristics of Premixed Hydrogen/Air in an Undulate Microchannel
Jan 2022
Publication
This work reports a numerical investigation of microcombustion in an undulate microchannel using premixed hydrogen and air to understand the effect of the burner design on the flame in order to obtain stability of the flame. The simulations were performed for a fixed equivalence ratio and a hyperbolic temperature profile imposed at the microchannel walls in order to mimic the heat external losses occurred in experimental setups. Due to the complexity of the flow dynamics combined with the combustion behavior the present study focuses on understanding the effect of the fuel inlet rate on the flame characteristics keeping other parameters constant. The results presented stable flame structure regardless of the inlet velocity for this type of design meaning that a significant reduction in the heat flux losses through the walls occurred allowing the design of new simpler systems. The increase in inlet velocity increased the flame extension with the flame being stretched along the microchannel. For higher velocities flame separation was observed with two detected different combustion zones and the temperature profiles along the burner centerline presented a non-monotonic decrease due to the dynamics of the vortices observed in the convex regions of the undulated geometry walls. The geometry effects on the flame structure flow field thermal evolution and species distribution for different inlet velocities are reported and discussed.
Investigation of Certain Mechanical and Magnetic Properties of a Stressed Low-carbon steel after corrosion in NaCl-water solution
Jun 2020
Publication
Atomic hydrogen produced by corrosion of a low-carbon steel in NaCl – Water solution may markedly affect its certain tensile mechanical and magnetic properties in a complex and peculiar manner. This influence was investigated by employing the intrinsic micromagnetic emission (ME)-response as well as tensile mechanical response of this ferromagnetic material and also by introduction a relevant measurement parameter of specific micromagnetic emission response. In this fashion it was shown that an increase in the hydrogen accumulation with corrosion time leads to an associated increase in the pervasive and embrittling influence expressed by a marked loss in ductility of the material. It was also shown that the competitive interplay of cumulative hydrogen applied stress and plastic strain-induced microstructural damage was related to a specific ME-response parameter by which an increased magnetic hardening tendency of material with corrosion time was established. In general embrittlement and magnetic hardening are parallel products of stress- assisted hydrogen accumulation where magnetic hardening process seems to be in a time processing advance of embrittlement one. The above findings allow to estimate that the magnetic properties are more susceptible to hydrogen effects than the mechanical ones.
Comparison of Conventional vs. Modular Hydrogen Refuelling Stations and On-Site Production vs. Delivery
Mar 2017
Publication
To meet the needs of public and private stakeholders involved in the development construction and operation of hydrogen fuelling stations needed to support the widespread roll-out of hydrogen fuel cell electric vehicles this work presents publicly available station templates and analyses. These ‘Reference Stations’ help reduce the cost and speed the deployment of hydrogen stations by providing a common baseline with which to start a design enable quick assessment of potential sites for a hydrogen station identify contributors to poor economics and suggest areas of research. This work presents layouts bills of materials piping and instrumentation diagrams and detailed analyses of five new station designs. In the near term delivered hydrogen results in a lower cost of hydrogen compared to on-site production via steam methane reforming or electrolysis although the on-site production methods have other advantages. Modular station concepts including on-site production can reduce lot sizes from conventional assemble-on-site stations.
Electrolyzer Modeling and Real-time Control for Optimized Production of Hydrogen Gas
Oct 2020
Publication
We present a method that operates an electrolyzer to meet the demand of a hydrogen refueling station in a cost-effective manner by solving a model-based optimal control problem. To formulate the underlying problem we first conduct an experimental characterization of a Siemens SILYZER 100 polymer electrolyte membrane electrolyzer with 100 kW of rated power. We run experiments to determine the electrolyzer’s conversion efficiency and thermal dynamics as well as the overload-limiting algorithm used in the electrolyzer. The resulting detailed nonlinear models are used to design a real-time optimal controller which is then implemented on the actual system. Each minute the controller solves a deterministic receding-horizon problem which seeks to minimize the cost of satisfying a given hydrogen demand while using a storage tank to take advantage of time-varying electricity prices and photovoltaic inflow. We illustrate in simulation the significant cost reduction achieved by our method compared to others in the literature and then validate our method by demonstrating it in real-time operation on the actual system.
Decarbonisation of Heat in Great Britain
Oct 2021
Publication
This study was conducted for a group of 15 clients in the public and private sectors interested in potential pathways for decarbonising residential heating and the impact of these pathways on the energy system. The ambition for all new heating installations to be low carbon from 2035 is essential to meeting the net zero target in 2050 and our study found that electricity demand for home heating is set to quadruple by 2050 as part of the shift away from gas-fired boilers.
The key findings from the study include:
The key findings from the study include:
- Phasing out natural gas boiler installations by 2035 is crucial for eliminating CO2 from home heating; delaying to 2040 could leave us with ¼ of today’s home heat emissions in 2050
- Achieving deployment of 600k heat pumps per year by 2028 will require policy intervention both to lower costs and to inform and protect consumers Almost £40bn could be saved in cumulative system costs by 2050 through adoption of more efficient and flexible electric heating technologies like networked heat pumps and storage
- Electricity demand from heating could quadruple by 2050 to over 100TWh per year almost a third of Great Britain’s current total annual electricity demand Using hydrogen for a share of heating could lower peak power demand although producing most of this hydrogen from electrolysis would raise overall power demand.
Overview of Power Electronic Converter Topologies Enabling Large-Scale Hydrogen Production via Water Electrolysis
Feb 2022
Publication
Renewable power-to-hydrogen (P2H) technology is one of the most promising solutions for fulfilling the increasing global demand for hydrogen and to buffer large-scale fluctuating renewable energies. The high-power high-current ac/dc converter plays a crucial role in P2H facilities transforming medium-voltage (MV) ac power to a large dc current to supply hydrogen electrolyzers. This work introduces the general requirements and overviews several power converter topologies for P2H systems. The performances of different topologies are evaluated and compared from multiple perspectives. Moreover the future trend of eliminating the line frequency transformer (LFT) is discussed. This work can provide guidance for future designing and implementing of power-electronics-based P2H systems.
Effect of Corrosion-induced Hydrogen Embrittlement and its Degradation Impact on Tensile Properties and Fracture Toughness of (Al-Cu-Mg) 2024 Alloy
Jul 2016
Publication
In the present work the effect of artificial ageing of AA2024-T3 on the tensile mechanical properties and fracture toughness degradation due to corrosion exposure will be investigated. Tensile and fracture toughness specimens were artificially aged to tempers that correspond to Under-Ageing (UA) Peak-Ageing (PA) and Over-Ageing (OA) conditions and then were subsequently exposed to exfoliation corrosion environment. The corrosion exposure time was selected to be the least possible according to the experimental work of Alexopoulos et al. (2016) so as to avoid the formation of large surface pits trying to simulate the hydrogen embrittlement degradation only. The mechanical test results show that minimum corrosion-induced decrease in elongation at fracture was achieved for the peak-ageing condition while maximum was noticed at the under-ageing and over-ageing conditions. Yield stress decrease due to corrosion is less sensitive to tempering; fracture toughness decrease was sensitive to ageing heat treatment thus proving that the S΄ particles play a significant role on the corrosion-induced degradation.
Recent Progress in Hydrogen Storage
Nov 2008
Publication
The ever-increasing demand for energy coupled with dwindling fossil fuel resources make the establishment of a clean and sustainable energy system a compelling need. Hydrogen-based energy systems offer potential solutions. Although in the long-term the ultimate technological challenge is large-scale hydrogen production from renewable sources the pressing issue is how to store hydrogen efficiently on board hydrogen fuel-cell vehicles.
Thoughts on the Prospects of Renewable Hydrogen
Oct 2020
Publication
In the last two years or so there has been increasing interest in hydrogen as an energy source in Australia and around the world. Notably this is not the first time that hydrogen has caught our collective interest. Most recently the 2000s saw a substantial investment in hydrogen research development and demonstration around the world. Prior to that the oil crises of the 1970s also stimulated significant investment in hydrogen and earlier still the literature on hydrogen was not lacking. And yet the hydrogen economy is still an idea only.<br/>So what if anything might be different this time?<br/>This is an important question that we all need to ask and for which the author can only give two potential answers. First our need to make dramatic reductions in greenhouse gas (GHG) emissions has become more pressing since these previous waves of interest. Second renewable energy is considerably more affordable now than it was before and it has consistently outperformed expectations in terms of cost reductions by even its strongest supporters.<br/>While this dramatic and ongoing reduction in the cost of renewables is very promising our need to achieve substantial GHG emission reductions is the crucial challenge. Moreover meeting this challenge needs to be achieved with as little adverse social and economic impact as possible.<br/>When considering what role hydrogen might play we should first think carefully about the massive scale and complexity of our global energy system and the typical prices of the major energy commodities. This provides insights into what opportunities hydrogen may have. Considering a temperate country with a small population like Australia we see that domestic natural gas and transport fuel markets are comparable to and even larger than the electricity market on an energy basis.
The Role of Critical Minerals in Clean Energy Transitions
May 2021
Publication
Minerals are essential components in many of today’s rapidly growing clean energy technologies – from wind turbines and electricity networks to electric vehicles. Demand for these minerals will grow quickly as clean energy transitions gather pace. This new World Energy Outlook Special Report provides the most comprehensive analysis to date of the complex links between these minerals and the prospects for a secure rapid transformation of the energy sector.
Alongside a wealth of detail on mineral demand prospects under different technology and policy assumptions it examines whether today’s mineral investments can meet the needs of a swiftly changing energy sector. It considers the task ahead to promote responsible and sustainable development of mineral resources and offers vital insights for policy makers including six key IEA recommendations for a new comprehensive approach to mineral security."
Link to International Energy Agency website
Alongside a wealth of detail on mineral demand prospects under different technology and policy assumptions it examines whether today’s mineral investments can meet the needs of a swiftly changing energy sector. It considers the task ahead to promote responsible and sustainable development of mineral resources and offers vital insights for policy makers including six key IEA recommendations for a new comprehensive approach to mineral security."
Link to International Energy Agency website
Microalloyed Steels through History until 2018: Review of Chemical Composition, Processing and Hydrogen Service
May 2018
Publication
Microalloyed steels have evolved in terms of their chemical composition processing and metallurgical characteristics since the beginning of the 20th century in the function of fabrication costs and mechanical properties required to obtain high-performance materials needed to accommodate for the growing demands of gas and hydrocarbons transport. As a result of this microalloyed steels present a good combination of high strength and ductility obtained through the addition of microalloying elements thermomechanical processing and controlled cooling processes capable of producing complex microstructures that improve the mechanical properties of steels. These controlled microstructures can be severely affected and result in catastrophic failures due to the atomic hydrogen diffusion that occurs during the corrosion process of pipeline steel. Recently a martensite–bainite microstructure with acicular ferrite has been chosen as a viable candidate to be used in environments with the presence of hydrogen. The aim of this review is to summarize the main changes of chemical composition processing techniques and the evolution of the mechanical properties throughout recent history on the use of microalloying in high strength low alloy steels as well as the effects of hydrogen in newly created pipelines examining the causes behind the mechanisms of hydrogen embrittlement in these steels.
Catalyst Engineering for Electrochemical Energy Conversion from Water to Water: Water Electrolysis and the Hydrogen Fuel Cell
May 2020
Publication
In the context of the current serious problems related to energy demand and climate change substantial progress has been made in developing a sustainable energy system. Electrochemical hydrogen–water conversion is an ideal energy system that can produce fuels via sustainable fossil-free pathways. However the energy conversion efficiency of two functioning technologies in this energy system—namely water electrolysis and the fuel cell—still has great scope for improvement. This review analyzes the energy dissipation of water electrolysis and the fuel cell in the hydrogen–water energy system and discusses the key barriers in the hydrogen- and oxygen-involving reactions that occur on the catalyst surface. By means of the scaling relations between reactive intermediates and their apparent catalytic performance this article summarizes the frameworks of the catalytic activity trends providing insights into the design of highly active electrocatalysts for the involved reactions. A series of structural engineering methodologies (including nanoarchitecture facet engineering polymorph engineering amorphization defect engineering element doping interface engineering and alloying) and their applications based on catalytic performance are then introduced with an emphasis on the rational guidance from previous theoretical and experimental studies. The key scientific problems in the electrochemical hydrogen–water conversion system are outlined and future directions are proposed for developing advanced catalysts for technologies with high energy-conversion efficiency.
Towards a Large-Scale Hydrogen Industry for Australia
Oct 2020
Publication
As nations around the world seek to reduce carbon dioxide emissions in order to mitigate climate change risks there has been a resurgence of interest in the use of hydrogen as a zero-emissions energy carrier. Hydrogen can be produced from diverse feedstocks via a range of low-emissions pathways and has broad potential in the process of decarbonization across the energy transport and industrial sectors.<br/>With an abundance of both renewable and fossil fuel energy resources a comparatively low national energy demand and excellent existing regional resource trading links Australia is well positioned to pursue industrial-scale hydrogen production for both domestic and export purposes. In this paper we present an overview of the progress at the government industry and research levels currently undertaken to enable a large-scale hydrogen industry for Australia.
Study on Temper Embrittlement and Hydrogen Embrittlement of a Hydrogenation Reactor by Small Punch Test
Jun 2017
Publication
The study on temper embrittlement and hydrogen embrittlement of a test block from a 3Cr1Mo1/4V hydrogenation reactor after ten years of service was carried out by small punch test (SPT) at different temperatures. The SPT fracture energy Esp (derived from integrating the load-displacement curve) divided by the maximum load (Fm) of SPT was used to fit the Esp/Fm versus-temperature curve to determine the energy transition temperature (Tsp) which corresponded to the ductile-brittle transition temperature of the Charpy impact test. The results indicated that the ratio of Esp/Fm could better represent the energy of transition in SPT compared with Esp. The ductile-to-brittle transition temperature of the four different types of materials was measured using the hydrogen charging test by SPT. These four types of materials included the base metal and the weld metal in the as-received state and the base metal and the weld metal in the de-embrittled state. The results showed that there was a degree of temper embrittlement in the base metal and the weld metal after ten years of service at 390 °C. The specimens became slightly more brittle but this was not obvious after hydrogen charging. Because the toughness of the material of the hydrogenation reactor was very good the flat samples of SPT could not characterize the energy transition temperature within the liquid nitrogen temperature. Additionally there was no synergetic effect of temper embrittlement and hydrogen embrittlement found in 3Cr1Mo1/4V steel.
Towards Non-Mechanical Hybrid Hydrogen Compression for Decentralized Hydrogen Facilities
Jun 2020
Publication
The cost of the hydrogen value chain needs to be reduced to allow the widespread development of hydrogen applications. Mechanical compressors widely used for compressing hydrogen to date account for more than 50% of the CAPEX (capital expenditure) in a hydrogen refuelling station. Moreover mechanical compressors have several disadvantages such as the presence of many moving parts hydrogen embrittlement and high consumption of energy. Non-mechanical hydrogen compressors have proven to be a valid alternative to mechanical compressors. Among these electrochemical compressors allow isothermal and therefore highly efficient compression of hydrogen. On the other hand adsorption-desorption compressors allow hydrogen to be compressed through cooling/heating cycles using highly microporous materials as hydrogen adsorbents. A non-mechanical hybrid hydrogen compressor consisting of a first electrochemical stage followed by a second stage driven by adsorption-desorption of hydrogen on activated carbons allows hydrogen to be produced at 70 MPa a value currently required for the development of hydrogen automotive applications. This system has several advantages over mechanical compressors such as the absence of moving parts and high compactness. Its use in decentralized hydrogen facilities such as hydrogen refuelling stations can be considered
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