Publications

This paper reviews previous research by the author in the field of hydrogen effects on progressively cold-drawn pearlitic steels in terms of hydrogen degradation (HD) hydrogen embrittlement (HE) or at the micro-level hydrogen-assisted micro-damage (HAMD) thus affecting their microstructural integrity and compromising the (macro-)structural integrity of civil engineering structures such as prestressed concrete bridges. It is seen that hydrogen effects in pearlitic microstructure (either oriented or not) are produced at the finest micro-level by plastic tearing in the form in general of hydrogen damage topography (HDT) with different appearances depending of the cold drawing degree evolving from the so-called tearing topography surface (TTS) in hot-rolled (not cold-drawn at all) or slightly cold-drawn pearlitic steels to a sort of enlarged and oriented TTS (EOTTS) in heavily drawn steels (the pronounced enlargement and marked orientation being along the wire axis or cold drawing direction). Whereas the pure TTS mode (null or low degree of cold drawing) resembles the Michelangello stone sculpture texture (MSST) the EOTTS mode does the same in relation to the Donatello wooden sculpture texture (DWST).

Concerns about greenhouse gases as well as the price and security of oil supply have acted as a spur to sustainable automobile development. The hydrogen fuel cells electric vehicle (HFCEV) is generally recognised by leading automobile manufacturers and scientists as one of the optimum technologies for long-term future low carbon vehicle. In a typical HFCEV power train a DC–DC converter is required to balance the voltage difference between the fuel cells (FCs) stack and batteries. However research shows that a considerable amount of energy generated by the hydrogen FCs stack is deplete during this conversion process as heat. This experiment aims to improve the power train efficiency by eliminating the DC–DC converter by finding the best combination of FC stack and batteries matching the size and capacity of the electrical components.

This analysis was conducted in support of the U.S. Department of Energy's H2@Scale initiative and this report examines the resources required to meet demand for an additional 10 million metric tonnes (MMT) of hydrogen in 2040. The technical potential of hydrogen production from fossil nuclear and renewable energy resources is presented. Updated maps describe the geographical distribution of hydrogen production potential from renewable energy resources. The results conclude that the technical resource availability of domestic energy resources is sufficient to meet an additional 10 MMT of hydrogen demand in 2040 without placing significant pressure on existing resources. While this level of hydrogen demand could result in a significant increase in renewable energy consumption in particular the technical potential of each resource is estimated to be sufficient to meet the demand. Future research to enable the large-scale integration of hydrogen in the U.S. energy and other sectors will include analyzing the geographic distribution of resources in relation to hydrogen demand for a variety of applications. Additional techno-economic analysis is also needed to understand the economic potential of hydrogen in other industries beyond transportation; such analysis is currently being undertaken by a multi-lab project initiated by DOE in 2016. Finally information from techno-economic analyses should be used to continually update and inform R&D targets for energy production hydrogen production and hydrogen utilization technologies.

This report fulfils Deliverable Five for Research Project 2.1-01 of the Future Fuels CRC. The aims of this project Crystallising lessons learned from major infrastructure upgrades are to provide a report on lessons learned from earlier infrastructure upgrades and fuel transitions and identify tools that can be used to develop consistent messaging around the proposed transition to hydrogen and/or other low-carbon fuels. In both the report and the toolkit there are recommendations on how to apply lessons learned and shape messaging throughout the value chain based on prior infrastructure upgrades.



This report presents three Australian case studies that that are relevant to the development of future fuels: the transition from town gas to natural gas the use of ethanol and LPG as motor fuels and the development of coal seam gas resources. Drawing on published information each case study provides an account of the issues that arose during the upgrade or transition and of the approaches through which industry and government stakeholders managed these issues. From these accounts lessons are identified that can guide stakeholder engagement in future infrastructure upgrades and fuel transitions. The findings from the case studies and academic literature have been used to develop an accompanying draft toolkit for use by FFCRC stakeholders.



The report also distils applicable lessons and frameworks from academic literature about stakeholder analysis megaprojects and the social acceptance of industries and technologies. This report is meant to be used in conjunction with a companion toolkit that provides a framework for making coordinated decisions across the fuel value chain.



You can read the full report on the Future Fuels CRC website here

All vehicular high-pressure hydrogen tanks are equipped with thermally-activated pressure relief devices (TPRDs) required by Global Technical Regulation. This safety device significantly reduces the risk of tank catastrophic rupture by venting the hydrogen pressure outside. However the released flammable hydrogen raises additional safety problems. Japan Automobile Research Institute has demonstrated that in the vehicle fire event once the TPRD opens the hydrogen fires will engulf the whole vehicle making it difficult for the drivers and passenger to evacuate from the vehicle. This paper designs a new safety system to solve the evacuation problem. The safety system includes a rotatable pressure relief device with a motor a sensory system that consists of infrared sensors ultrasonic radar and temperature sensors a central control unit and an alarm device. The new design of the pressure relief device allows the system actively adjusting the release direction towards void open space outside the vehicle to minimize the risks of hydrogen fires. The infrared sensors located at the roof of the vehicles collect info inside the vehicle and the ultrasonic radar detect the region outside the vehicle. Temperature sensors tell when to trigger the alarm and set the motor in standby mode and the central control unit determines where to rotate based on the info from the infrared sensors and ultrasonic radars. A control strategy is also proposed to operate the safety system in an appropriate way. The cost-benefit analysis show that the new safety system can significantly reduce the risks of intended hydrogen releases from onboard pressure relief devices with total cost increases by less than 1% of the vehicle cost making it a good cost-effective engineering solution.

Herein the hydrogen embrittlement of a heat-affected zone (HAZ) was examined using slow strain rate tension in situ hydrogen charging. The influence of hydrogen on the crack path of the HAZ sample surfaces was determined using electron back scatter diffraction analysis. The hydrogen embrittlement susceptibility of the base metal and the HAZ samples increased with increasing current density. The HAZ samples have lower resistance to hydrogen embrittlement than the base metal samples in the same current density. Brittle circumferential cracks located at the HAZ sample surfaces were perpendicular to the loading direction and the crack propagation path indicated that five or more cracks may join together to form a longer crack. The fracture morphologies were found to be a mixture of intergranular and transgranular fractures. Hydrogen blisters were observed on the HAZ sample surfaces after conducting tensile tests at a current density of 40 mA/cm2 leading to a fracture in the elastic deformation stage.

The paper presents a sustainable electric powertrain for a transit city bus featuring an electrochemical battery-free power unit consisting of a hydrogen fuel cell stack and a kinetic energy storage system based on high-speed flywheels. A rare-earth free high-efficiency motor technology is adopted to pursue a more sustainable vehicle architecture by limiting the use of critical raw materials. A suitable dynamic energetic model of the full vehicle powertrain has been developed to investigate the feasibility of the traction system and the related energy management control strategy. The model includes losses characterisation as a function of the load of the main components of the powertrain by using experimental tests and literature data. The performance of the proposed solution is evaluated by simulating a vehicle mission on an urban path in real traffic conditions. Considerations about the effectiveness of the traction system are discussed.

A promising option for storing large-scale quantities of green gases (e.g. hydrogen) is in subsurface rock salt caverns. The mechanical performance of salt caverns utilized for long-term subsurface energy storage plays a signifcant role in long-term stability and serviceability. However rock salt undergoes non-linear creep deformation due to long-term loading caused by subsurface storage. Salt caverns have complex geometries and the geological domain surrounding salt caverns has a vast amount of material heterogeneity. To safely store gases in caverns a thorough analysis of the geological domain becomes crucial. To date few studies have attempted to analyze the infuence of geometrical and material heterogeneity on the state of stress in salt caverns subjected to long-term loading. In this work we present a rigorous and systematic modeling study to quantify the impact of heterogeneity on the deformation of salt caverns and quantify the state of stress around the caverns. A 2D fnite element simulator was developed to consistently account for the non-linear creep deformation and also to model tertiary creep. The computational scheme was benchmarked with the already existing experimental study. The impact of cyclic loading on the cavern was studied considering maximum and minimum pressure that depends on lithostatic pressure. The infuence of geometric heterogeneity such as irregularly-shaped caverns and material heterogeneity which involves diferent elastic and creep properties of the diferent materials in the geological domain is rigorously studied and quantifed. Moreover multi-cavern simulations are conducted to investigate the infuence of a cavern on the adjacent caverns. An elaborate sensitivity analysis of parameters involved with creep and damage constitutive laws is performed to understand the infuence of creep and damage on deformation and stress evolution around the salt cavern confgurations.

Hydrogen compression is a key part of the green hydrogen supply chain but mechanical compressors are prone to failure and add system complexity and cost. High-pressure water electrolysis can alleviate this problem through electrochemical compression of the gas internally in the electrolyzer and thereby eliminating the need for an external hydrogen compressor. In this work a detailed techno-economic assessment of high-pressure proton exchange membrane-based water electrolysis (PEMEL) systems was carried out. Electrolyzers operating at 80 200 350 and 700 bar were compared to state-of-the-art systems operating at 30 bar in combination with a mechanical compressor. The results show that it is possible to achieve economically viable solutions with high-pressure PEMEL-systems operating up to 200 bar. These pressure levels fit well with the requirements in existing and future industrial applications such as e-fuel production (30–120 bar) injection of hydrogen into natural gas grids (70 bar) hydrogen gas storage (≥200 bar) and ammonia production (200–300 bar). A sensitivity analysis also showed that if the cost of electricity is sufficiently low (

Palladium (Pd) membranes are a promising enabling technology for power generation and hydrogen production with CO2 capture. SINTEF has developed and patented a flexible technology to produce Pd-alloy membranes that significantly improves flux and thereby reduces material costs. Reinertsen AS and SINTEF aim to demonstrate the Pd membrane technology for H2 separation on a side stream of the Statoil Methanol Plant at Tjeldbergodden Norway. In the present article we present the upscaling of the membrane manufacturing process together with the membrane module and skid design and construction.

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.

In super duplex stainless steels (SDSSs) both austenite and ferrite are susceptible to hydrogen embrittlement however there is a lack of understanding into the effect of hydrogen in each phase. In this study in neutron diffraction was applied on hydrogen-charged (H-charged) samples to investigate the hydrogen embrittlement behaviour in super duplex stainless steels. The result reveals that austenite maintains good plasticity during tensile testing whilst a loss of it is realised in ferrite. Fractography analysis reveals the diffusion of hydrogen induced a brittle-to-ductile transition from the sample surface towards the centre; hydrogen embrittlement vanishes as the specimen’s centre is approached while it is demonstrated to disappear first in austenite but not in ferrite. This transition can be predicted by applying a physics-based hydrogen embrittlement model which incorporates the effects of hydrogen concentration hydrogen diffusivity residual stress loading state and temperature. The present work demonstrates the dissimilar susceptibility of austenite and ferrite to hydrogen embrittlement providing a tool to describe it.

Hydrogen sourced from energy recovery processes and conversion of waste materials is a method of providing both a clean fuel and a sustainable waste management alternative to landfill and incineration. The question is whether waste-to–hydrogen can become part of the zero-carbon future energy mix and serve as one of the cleaner hydrogen sources which is economically viable and environmentally friendly. This work critically assessed the potential of waste as a source of hydrogen production via various thermochemical (gasification and pyrolysis) and biochemical (fermentation and photolysis) processes. Research has shown hydrogen production yields of 33.6 mol/kg and hydrogen concentrations of 82% from mixed waste feedstock gasification. Biochemical methods such as fermentation can produce hydrogen up to 418.6 mL/g. Factors including feedstock quality process requirements and technology availability were reviewed to guide technology selection and system design. Current technology status and bottlenecks were discussed to shape future development priorities. These bottlenecks include expensive production and operation processes heterogeneous feedstock low process efficiencies inadequate management and logistics and lack of policy support. Improvements to hydrogen yields and production rates are related to feedstock processing and advanced energy efficiency processes such as torrefaction of feedstock which has shown thermal efficiency of gasification up to 4 MJ/kg. This will affect the economic feasibility and concerns around required improvements to bring the costs down to allow waste to viewed as a serious competitor for hydrogen production. Recommendations were also made for financially competitive waste-to-hydrogen development to be part of a combined solution for future energy needs.

Effects of hydrogen on slow-strain-rate tensile (SSRT) and fatigue-life properties of 17-4PH H1150 martensitic stainless steel having an ultimate tensile strength of ~1GPa were investigated. Smooth and circumferentially-notched axisymmetric specimens were used for the SSRT and fatigue-life tests respectively. The fatigue-life tests were done to investigate the hydrogen effect on fatigue crack growth (FCG) properties. The specimens tested in air at ambient temperature were precharged by exposure to hydrogen gas at pressures of 35 and 100 MPa at 270°C for 200 h. The SSRT properties of the H-charged specimens were degraded by hydrogen showing a relative reduction in area (RRA) of 0.31 accompanied by mixed fracture surfaces composed of quasi-cleavage (QC) and intergranular cracking (IG). The fatigue-life tests conducted under wide test frequencies ranging from 10-3 Hz to 10 Hz revealed three distinct characteristics in low- and high-cycle regimes and at the fatigue limit. The fatigue limit was not degraded by hydrogen. In the high-cycle regime the hydrogen caused FCG acceleration with an upper bound ratio of 30 accompanied by QC surfaces. In the low-cycle regime the hydrogen caused FCG acceleration with a ratio of ~100 accompanied by QC and IG. The ordinary models such as process competition and superposition models hardly predicted the H-assisted FCG acceleration; therefore an interaction model successfully reproducing the experimental FCG acceleration was newly introduced.

Lamination-like defects in pipeline steels can be of both metallurgical and operational origin. In pipelines transporting hydrocarbon usually such defects are not a big challenge since they do not propagate under operating conditions. Nonetheless in presence of a corrosion phenomenon and sour gas (H2S) it is possible to observe blisters and cracks which may propagate in the steel. The observed damage mechanisms is Hydrogen Embrittlement and in spite of a huge amount of study and publications available it is quite difficult for a pipeline owner to get practical data (crack propagation rate for instance) allowing a reliable estimate of the fitness for service of a pipeline. Taking advantage of a pipeline spool containing internal defects that was in service for more than 10 years and recently removed a comprehensive study is underway to obtain a complete assessment of the pipeline future integrity. The program is comprehensive of study and comparison of ILI reports of the pipeline to determine the optimum interval between inspections assessment of inspection results via an accurate nondestructive (UT) and destructive examination of the removed section to verify ILI results lab tests program on specimens from the removed spool at operating conditions (75-80 bar and 30°-36° C) in presence of a small quantity of water H2S (5%) and CO2 (7%) in order to assess defect propagation and to obtain an estimate of crack growth rate and test in field of available methods to monitor the presence of Hydrogen and/or the growth of defects in in-service pipelines. This quite ambitious program is also expected to be able of offering a small contribution toward a better understanding of HE mechanisms and the engineering application of such complex often mainly academic studies.

This report identifies and assesses a range of high-level deployment options for industrial carbon capture usage and storage (CCUS) technology located in non-clustered ‘dispersed’ sites that are isolated from potential carbon dioxide transport infrastructure in the UK.

It provides:

• an identification of the challenges and barriers to CCUS deployment specifically at these dispersed sites
• an appraisal of the range of high-level options for CCUS deployment and the risks associated with each challenge
• an assessment of the most promising options based on their cost risk and emission reduction potential
• BEIS commissioned Element Energy to produce the report.

In the field of energy storage recently investigated nanocomposites show promise in terms of high hydrogen uptake and release with enhancement in the reaction kinetics. Among several carbonaceous nanovariants like carbon nanotubes (CNTs) fullerenes and graphitic nanofibers reveal reversible hydrogen sorption characteristics at 77 K due to their van der Waals interaction. The spillover mechanism combining Pd nanoparticles on the host metal-organic framework (MOF) show room temperature uptake of hydrogen. Metal or complex hydrides either in the nanocomposite form and its subset nanocatalyst dispersed alloy phases illustrate the concept of nanoengineering and nanoconfinement of particles with tailor-made properties for reversible hydrogen storage. Another class of materials comprising polymeric nanostructures such as conducting polyaniline and their functionalized nanocomposites are versatile hydrogen storage materials because of their unique size high specific surface-area pore-volume and bulk properties. The salient features of nanocomposite materials for reversible hydrogen storage are reviewed and discussed.

There is uncertainty over how heating might practically be decarbonised in the future. This briefing provides some clarity about the possible pathways forward focusing on the next 5-10 years.<br/>Meeting the UK government’s net zero emissions goal for 2050 will only be possible by complete decarbonisation of the building stock (both existing and new).  There is uncertainty over the extent to which heating might practically be decarbonised in the future and what the optimal technologies may be. This paper provides some clarity about the pathways forward focusing on the next 5-10 years.

Fuel cell electric vehicles convert chemical energy of hydrogen into electricity to power their motor. Since cars are used for transport only during a small part of the time energy stored in the on-board hydrogen tanks of fuel cell vehicles can be used to provide power when cars are parked. In this paper we present a community microgrid with photovoltaic systems wind turbines and fuel cell electric vehicles that are used to provide vehicle-to-grid power when renewable power generation is scarce. Excess renewable power generation is used to produce hydrogen which is stored in a refilling station. A central control system is designed to operate the system in such a way that the operational costs are minimized. To this end a hybrid model for the system is derived in which both the characteristics of the fuel cell vehicles and their traveling schedules are considered. The operational costs of the system are formulated considering the presence of uncertainty in the prediction of the load and renewable energy generation. A robust minmax model predictive control scheme is developed and finally a case study illustrates the performance of the designed system.

The locally occurring mechanisms of hydrogen embrittlement significantly influence the fatigue behaviour of a material which was shown in previous research on two different AISI 300-series austenitic stainless steels with different austenite stabilities. In this preliminary work an enhanced fatigue crack growth as well as changes in crack initiation sites and morphology caused by hydrogen were observed. To further analyze the results obtained in this previous research in the present work the local cyclic deformation behaviour of the material volume was analyzed by using cyclic indentation testing. Moreover these results were correlated to the local dislocation structures obtained with transmission electron microscopy (TEM) in the vicinity of fatigue cracks. The cyclic indentation tests show a decreased cyclic hardening potential as well as an increased dislocation mobility for the conditions precharged with hydrogen which correlates to the TEM analysis revealing courser dislocation cells in the vicinity of the fatigue crack tip. Consequently the presented results indicate that the hydrogen enhanced localized plasticity (HELP) mechanism leads to accelerated crack growth and change in crack morphology for the materials investigated. In summary the cyclic indentation tests show a high potential for an analysis of the effects of hydrogen on the local cyclic deformation behaviour.

Solar-driven electrolysis of water to generate hydrogen is emerging as a viable strategy to decarbonize the global energy economy. However this direction is more expensive than traditional fossil fuel generation of hydrogen and effective pathways to lower this cost need to be identified. Here we report a Monte Carlo approach to explore a wide range of input assumptions to identify key cost drivers targets and localized conditions necessary for competitive stand-alone dedicated PV powered hydrogen electrolysis. We determine the levelized cost of hydrogen (LCOH) considering historical weather data for specific locations to model our PV system and optimize its size compared to the electrolyzer. This analysis and its methods show the potential for green hydrogen production using off-grid PV shows the merits of remote systems in areas of high solar resource and provides cost and performance targets for electrolyzer technologies.

This paper presents the results of a demonstration project including building-integrated photovoltaic (BIPV) solar panels a residential building and a hydrogen fuel cell electric vehicle (FCEV) for combined mobility and power generation aiming to achieve a net zero-energy residential building target. The experiment was conducted as part of the Car as Power Plant project at The Green Village in the Netherlands. The main objective was to assess the end-user’s potential of implementing FCEVs in vehicle-to-grid operation (FCEV2G) to act as a local energy source. FCEV2G field test performance with a Hyundai ix35 FCEV are presented. The car was adapted using a power output socket capable of delivering up to 10 kW direct current (DC) to the alternating current (AC) national grid when parked via an off-board (grid-tie) inverter. A Tank-To-AC-Grid efficiency (analogous to Tank- To-Wheel efficiency when driving) of 44% (measured on a Higher Heating Value basis) was obtained when the car was operating in vehicle-to-grid (V2G) mode at the maximum power output. By collecting and analysing real data on the FCEV power production in V2G mode and on BIPV production and household consumption two different operating modes for the FCEV offering balanced services to a residential microgrid were identified namely fixed power output and load following. Based on the data collected one-year simulations of a microgrid consisting of 10 all-electric dwellings and 5 cars with the different FCEV2G modes of operation were performed. Simulation results were evaluated on the factors of autonomy self-consumption of locally produced energy and net-energy consumption by implementing different energy indicators. The results show that utilizing an FCEV working in V2G mode can reduce the annual imported electricity from the grid by approximately 71% over one year and aiding the buildings in the microgrid to achieve a net zero-energy building target. Furthermore the simulation results show that utilizing the FCEV2G setup in both modes analysed could be economically beneficial for the end-user if hydrogen prices at the pump fall below 8.24 €/kg.

Pathways leading to a carbon neutral future for the German energy system have to deal with the expected phase-out of coal-fired power generation in addition to the shutdown of nuclear power plants and the rapid ramp-up of photovoltaics and wind power generation. An analysis of the expected impact on electricity market security of supply and system stability must consider the European context because of the strong coupling—both from an economic and a system operation point of view—through the cross-border power exchange of Germany with its neighbors. This analysis complemented by options to improve the existing development plans is the purpose of this paper. We propose a multilevel energy system modeling including electricity market network congestion management and system stability to identify challenges for the years 2023 and 2035. Out of the results we would like to highlight the positive role of innovative combined heat and power (CHP) solutions securing power and heat supply the importance of a network congestion management utilizing flexibility from sector coupling and the essential network extension plans. Network congestion and reduced security margins will become the new normal. We conclude that future energy systems require expanded flexibilities in combination with forward planning of operation.

Global demand for data and data access has spurred the rapid growth of the data center industry. To meet demands data centers must provide uninterrupted service even during the loss of primary power. Service providers seeking ways to eliminate their carbon footprint are increasingly looking to clean and sustainable energy solutions such as hydrogen technologies as alternatives to traditional backup generators. In this viewpoint a survey of the current state of data centers and hydrogen-based technologies is provided along with a discussion of the hydrogen storage and infrastructure requirements needed for large-scale backup power applications at data centers.

Delft University of Technology under its ‘‘Green Village” programme has an initiative to build a power plant (car parking lot) based on the fuel cells used in vehicles for motive power. It is a trigeneration system capable of producing electricity heat and hydrogen. It comprises three main zones: a hydrogen production zone a parking zone and a pump station zone. This study focuses mainly on the hydrogen production zone which assesses four different system designs in two different operation modes of the facility: Car as Power Plant (CaPP) mode corresponding to the open period of the facility which uses fuel cell electric vehicles (FCEVs) as energy and water producers while parked; and Pump mode corresponding to the closed period which compresses the hydrogen and pumps to the vehicle’s fuel tank. These system designs differ by the reforming technology: the existing catalytic reformer (CR) and a solid oxide fuel cell operating as reformer (SOFCR); and the option of integrating a carbon capture and storage (CCS). Results reveal that the SOFCR unit significantly reduces the exergy destruction resulting in an improvement of efficiency over 20% in SOFCR-based system designs compared to CR-based system designs in both operation modes. It also mitigates the reduction in system efficiency by integration of a CCS unit achieving a value of 2% whereas in CR-based systems is 7–8%. The SOFCR-based system running in Pump mode achieves a trigeneration efficiency of 60%.

Hydrogen is one of the main candidates in replacing fossil fuels in the forthcoming years. However hydrogen technologies must deal with safety aspects due to the specific substance properties. This study aims to provide an overview on the loss of integrity (LOI) of hydrogen equipment which may lead to serious consequences such as fires and explosions. Substantial information regarding the hydrogen lifecycle its properties and safety related aspects has gathered. Furthermore focus has placed on the phenomena responsible for the LOI (e.g. hydrogen embrittlement) and material selection for hydrogen services. Moreover a systematic review on the hydrogen LOI topic has conducted to identify and connect the most relevant and active research group within the topic. In conclusion a significant dearth of knowledge in material behaviour of hydrogen technologies has highlighted. It is thought that is possible to bridge this gap by strengthening the collaborations between scientists from different research fields.

Alberta is preparing for a lower emission future. The Hydrogen Roadmap is a key part of that future and Alberta's Recovery Plan. The roadmap is our path to building a provincial hydrogen economy and accessing global markets. It contains several policy actions that will be introduced in the coming months and years and it provides support to the sector as technology and markets develop.<br/>Alberta is already the largest hydrogen producer in Canada. We have all the resources expertise and technology needed to quickly become a global supplier of clean low-cost hydrogen. With a worldwide market estimated to be worth over $2.5 trillion a year by 2050 hydrogen can be the next great energy export that fuels jobs investment and economic opportunity across our province.

Extreme halophiles offer the advantage to save on the costs of sterilization and water for biohydrogen production from lignocellulosic waste after the pretreatment process with their ability to withstand extreme salt concentrations. This study identifies the dominant hydrogen-producing genera and species among the acclimatized extremely halotolerant microbial communities taken from two salt-damaged soil locations in Khon Kaen and one location from the salt evaporation pond in Samut Sakhon Thailand. The microbial communities’ V3–V4 regions of 16srRNA were analyzed using high-throughput amplicon sequencing. A total of 345 operational taxonomic units were obtained and the high-throughput sequencing confirmed that Firmicutes was the dominant phyla of the three communities. Halanaerobium fermentans and Halanaerobacter lacunarum were the dominant hydrogen-producing species of the communities. Spatial proximity was not found to be a determining factor for similarities between these extremely halophilic microbial communities. Through the study of the microbial communities strategies can be developed to increase biohydrogen molar yield.

Direct CO₂ hydrogenation to hydrocarbons is a promising method of reducing CO2 emissions along with producing value-added products. However reactor design and performance have remained a challenging issue because of low olefin efficiency and high water production as a by-product. Accordingly a one-dimensional non-isothermal mathematical model is proposed to predict the membrane reactor performance and statistical analysis is used to assess the effects of important variables such as temperatures of reactor (Tr:A) shell (Ts:B) and tube (Tt:C) as well as sweep ratio (θ:D) and pressure ratio (φ:E) and their interactions on the products yields. In addition the optimized operating conditions are also obtained to achieve maximum olefin yields. Results reveal that interacting effects comprising AB (TrTs) AC (TrTt) AE (Trφ) BC (TsTt) CE (Ttφ) CD (Ttθ) and DE (θφ) play important roles on the product yields. It is concluded that higher temperatures at low sweep and pressure ratios can maximize the yields of olefins while simultaneously the yields of paraffins are minimized. In this regard optimized values for Tr Ts Tt θ and φ are determined as 325 °C 306.96 °C 325 °C 1 and 1 respectively.

The role of hydrogen in future energy systems is widely acknowledged: from fuel for difficult-to-decarbonize applications to feedstock for chemicals synthesis to energy storage for high penetration of undispatchable renewable electricity. While several literature studies investigate such energy systems the details of how electrolysers and renewable technologies optimally behave and interact remain an open question. With this work we study the interplay between (i) renewable electricity generation through wind and solar (ii) electricity storage in batteries (iii) electricity storage via Power-to-H2 and (iv) hydrogen commodity demand. We do so by designing a cost-optimal zero-emission energy system and use the Netherlands as a case study in a mixed integer linear model with hourly resolution for a time horizon of one year. To account for the significant role of wind we also provide an elaborate approach to model broad portfolios of wind turbines. The results show that if electrolyzers can operate flexibly batteries and power-to-H2-to-power are complementary with the latter using renewable power peaks and the former using lower renewable power outputs. If the operating modes of the power-to-H2-to-power system are limited - artificially or technically - the competitive advantage over batteries decreases. The preference of electrolyzers for power peaks also leads to an increase in renewable energy utilization for increased levels of operation flexibility highlighting the importance of capturing this feature both from a technical and a modeling perspective. When adding a commodity hydrogen demand the amount of hydrogen converted to electricity decreases hence decreasing its role as electricity storage medium.

The need for energy and water security on islands has led to an increase in the use of wind power. However the intermittent nature of wind generation means it needs to be coupled with a storage system. Motivated by this two different models of surplus energy storage systems are investigated in this paper. In both models renewable wind energy is provided by a wind farm. In the first model a pumped hydro storage system (PHS) is used for surplus energy storage while in the second scenario a hybrid pumped hydrogen storage system (HPHS) is applied consisting of a PHS and a hydrogen storage system. The goal of this study is to compare the single and the hybrid storage system to fulfill the energy requirements of the island’s electricity load and desalination demands for domestic and irrigation water. The cost of energy (COE) is 0.287 EUR/kWh for PHS and 0.360 EUR/kWh for HPHS while the loss of load probability (LOLP) is 22.65% for PHS and 19.47% for HPHS. Sensitivity analysis shows that wind speed is the key parameter that most affects COE cost of water (COW) and LOLP indices while temperature affects the results the least.

The hydrogen economy will play a key role in future energy systems. Several thermal and catalytic methods for hydrogen production have been presented. In this review methane thermocatalytic and thermal decomposition into hydrogen gas and solid carbon are considered. These processes known as the thermal decomposition of methane (TDM) and thermocatalytic decomposition (TCD) of methane respectively appear to have the greatest potential for hydrogen production. In particular the focus is on the different types and properties of carbons formed during the decomposition processes. The applications for carbons are also investigated.

The potential benefits are examined of the “Power-to-Gas” (P2G) scheme to utilize excess wind power capacity by generating hydrogen (or potentially methane) for use in the natural gas distribution grid. A parametric analysis is used to determine the feasibility and size of systems producing hydrogen that would be injected into the natural gas grid. Specifically wind farms located in southwestern Ontario Canada are considered. Infrastructure requirements wind farm size pipeline capacity geographical dispersion hydrogen production rate capital and operating costs are used as performance measures. The model takes into account the potential production rate of hydrogen and the rate that it can be injected into the local gas grid. “Straw man” systems are examined centered on a wind farm size of 100 MW integrating a 16-MW capacity electrolysis system typically producing 4700 kg of hydrogen per day.

This paper covers the hydrogen technologies regarding the role of hydrogen as an energy carrier and the possibilities of its production and use. It is initially presented the modalities and the efficiency of the current technologies of obtaining hydrogen detailing its obtaining by the electrolysis of the water the electrochemical efficiency and the specific consumption of electricity as well as the thermodynamics of the electrochemical processes. The following paragraph addresses hydrogen conversion possibilities. This paragraph details the thermodynamic analysis of the fuel cell the external characteristic of the fuel cell and the types of fuel cell. The last paragraph addresses the possibilities of using the fuel cells for electrical vehicles and cogeneration systems for buildings.In this context the traditional transport and distribution grid will have to adapt to the new realities as they will need to actively participate in the internal energy market by the transformation of the traditional electricity grid in energy flow from unidirectional to bidirectional through the production of hydrogen offering the same facilities as the gas grid.

The presented research focuses on an optimization design of a catalyst distribution inside a small-scale methane/steam reforming reactor. A genetic algorithm was used for the multiobjective optimization which included the search for an optimum of methane conversion rate and a minimum of the difference between highest and lowest temperatures in the reactor. For the sake of computational time the maximal number of the segment with different catalyst densities was set to be thirty in this study. During the entire optimization process every part of the reactor could be filled either with a catalyst material or non-catalytic metallic foam. In both cases the porosity and pore size was also specified. The impact of the porosity and pore size on the active reaction surface and permeability was incorporated using graph theory and three-dimensional digital material representation. Calculations start with the generation of a random set of possible reactors each with a different catalyst distribution. The algorithm calls reforming simulation over each of the reactors and after obtaining concentration and temperature fields the algorithms calculated fitness function. The properties of the best reactors are combined to generate a new population of solutions. The procedure is repeated and after meeting the coverage criteria the optimal catalyst distribution was proposed. The paper is summarized with the optimal catalyst distribution for the given size and working conditions of the system.

Waterborne transport contributes to around 14% of the overall greenhouse gas emissions of transport in the European Union and it is among the most efficient modes of transport. Nonetheless considering the aim of making the European Union carbon-neutral by 2050 and the fundamental role of waterborne transport within the European economy effort is needed to reduce its environmental impact. This paper provides an assessment of research and innovation measures aiming at decreasing waterborne transport’s CO2 emissions by assessing European projects based on the European Commission’s Transport Research and Innovation Monitoring and Information System (TRIMIS). Additionally it provides an outlook of the evolution of scientific publications and intellectual property activity in the area. The review of project findings suggests that there is no single measure which can be considered as a problem solver in the area of the reduction of waterborne CO2 emissions and only the combination of different innovations should enable reaching this goal. The highlighted potential innovations include further development of lightweight composite materials innovative hull repair methods wind assisted propulsion engine efficiency waste heat electrification hydrogen and alternative fuels. The assessment shows prevalence of funding allocated to technological measures; however non-technological ones like improved vessel navigation and allocation systems also show a great potential for the reduction of CO2 emissions and reduction of negative environmental impacts of waterborne transport.

The strength against fracture nucleation from an interface free-edge of silicon-nitride (SiN)/copper (Cu) micro-components is evaluated. A special technique that combines a nano-indenter specimen holder and an environmental transmission electron microscope (E-TEM) is employed. The critical load at the onset of fracture nucleation from a wedge-shaped free-edge (opening angle: 90°) is measured both in a vacuum and in a hydrogen (H₂) environment and the critical stress distribution is evaluated by the finite element method (FEM). It is found that the fracture nucleation is dominated by the near-edge elastic singular stress field that extends about a few tens of nanometers from the edge. The fracture nucleation strength expressed in terms of the stress intensity factor (K) is found to be eminently reduced in a H2 environment.

Unintended releases can occur during the production storage transportation and filling of liquid hydrogen which may cause devastating consequences. In the present work liquid hydrogen leak is modeled in ANSYS Fluent with the numerical model validated using the liquid hydrogen spill test data. A three-layer artificial neural network (ANN) model is built in which the wind speed ground temperature leakage time and leakage rate are taken as the inputs the horizontal diffusion distance and vertical diffusion distance of combustible gas as the outputs of the ANN. The representative sample data derived from the detailed calculation results of the numerical model are selected via the orthogonal experiment method to train and verify the back propagation (BP) neural network. Comparing the calculation results of the formula fitting with the sample data the results show that the established ANN model can quickly and accurately predict the horizontal and vertical diffusion distance of flammable vapor cloud relatively. The influences of four parameters on the horizontal hazard distance as well as vertical hazard height are predicted and analyzed in the case of continuous overflow of liquid hydrogen using the ANN model.

On 26 June the World Energy Council held a webinar presenting the results of its latest Innovation Insights Brief on hydrogen engaging three key experts on the topic:



Nigel Brandon Dean of the Faculty of Engineering Imperial College London



Craig Knight Director of Industrial Solutions Horizon Fuel Cell Technology



Dan Sadler H21 Project Manager for Equinor



During the webinar the experts answered a series of policy technical and safety questions from the audience. The webinar started with a poll to get a sense of which sectors attendees saw hydrogen playing a key role in 2040 - 77% chose industrial processes 54% mobility and 31% power generation. The questions ranged from the opportunities and limitations of blending hydrogen with natural gas to safety concerns surrounding hydrogen.



KEY HIGHLIGHTS:

How much hydrogen can be blended with natural gas depends on the rules and regulation of each country. The general consensus is that blending 10% by volume of hydrogen presents no safety concerns or specific difficulties. This would provide an opportunity to develop low hydrogen markets. Nevertheless blending should not be the end destination. It is not sufficient to meet carbon abatement targets.



Low carbon ammonia has a role to play in the new hydrogen economy. It is a proven and understood technology which is easier to move around the world and could be used directly as ammonia or cracked back into hydrogen.



One of the main focus today should be to replace grey hydrogen with green hydrogen in existing supply chains as there would be no efficiency losses in the process.



In China the push for hydrogen is transport-related. This is driven by air quality and energy independence concerns. In the next 10 years the full life cost of fuel cell electric vehicles (FCEVs) is expected to be lower than for internal combustion engines. This is due to the fact that FCEVs require less maintenance and that the residual value in the fuel cells is relatively high. At the end of life 95% of the platinum in fuel cells can be repurposed.



FCEVs should not be regarded as competing with battery electric vehicles they sit next to each other on product maps. FCEVs can benefit from the all of the advances in electric drive train systems and electric motors.



To close the webinar attendees were asked whether hydrogen was going through another hype cycle or if it was here to stay. 10% answered hype and 90% here to stay.

Dark fermentation is a promising method to produce hydrogen from lignocellulosic biomass. This study assessed the influence of temperature phosphate buffer concentration and substrate concentration on direct hydrogen production form cellulose using response surface methodology. Mixed bacterial culture was successfully enriched on cellulose and used as an inoculum for hydrogen production. The model indicated that the highest cumulative hydrogen production (CHP) of 2.14 L H₂/Lmedium could be obtained at 13.5 gcellulose/L 79.5 mM buffer and 32.6 °C. However hydrogen yield is then only 0.58 mol H₂/molhexose due to low substrate conversion efficiency (SCE). Simultaneous optimization of CHP and SCE with desirability function approach resulted in the H₂ yield of 2.71 ± 0.1 mol H2/molhexose and 93.8 ± 1.8% SCE at 3.35 gcellulose/L 69 mM buffer and 32.9 °C. Phosphate concentration above 80 mM decreased H₂ production but had positive effect on cellulose consumption. The bacterial community analysis showed that Ruminiclostridium papyrosolvens was responsible for cellulose hydrolysis. Lachnoclostridium sp. was positively correlated with ethanol production at high phosphate buffer concentration while Caproiciproducens sp. with caproate production at low buffer concentration. The obtained results opens the possibility of simultaneous hydrogen and caproate production from cellulosic substrates.

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.

Green hydrogen produced from wind solar or hydro power is a suitable electricity storage medium. Hydrogen is typically employed as mid- to long-term energy storage whereas batteries cover short-term energy storage. Green hydrogen can be produced by any available electrolyser technology [alkaline electrolysis cell (AEC) polymer electrolyte membrane (PEM) anion exchange membrane (AEM) solid oxide electrolysis cell (SOEC)] if the electrolysis is fed by renewable electricity. If the electrolysis operates under elevated pressure the simplest way to store the gaseous hydrogen is to feed it directly into an ordinary pressure vessel without any external compression. The most efficient way to generate electricity from hydrogen is by utilizing a fuel cell. PEM fuel cells seem to be the most favourable way to do so. To increase the capacity factor of fuel cells and electrolysers both functionalities can be integrated into one device by using the same stack. Within this article different reversible technologies as well as their advantages and readiness levels are presented and their potential limitations are also discussed.

The results of a techno-economic model of distributed wind-hydrogen systems (WHS) located at each existing wind farm on the island of Ireland are presented in this paper. Hydrogen is produced by water electrolysis from wind energy and backed up by grid electricity compressed before temporarily stored then transported to the nearest injection location on the natural gas network. The model employs a novel correlation-based approach to select an optimum electrolyser capacity that generates a minimum levelised cost of hydrogen production (LCOH) for each WHS. Three scenarios of electrolyser operation are studied: (1) curtailed wind (2) available wind and (3) full capacity operations. Additionally two sets of input parameters are used: (1) current and (2) future techno-economic parameters. Additionally two electricity prices are considered: (1) low and (2) high prices. A closest facility algorithm in a geographic information system (GIS) package identifies the shortest routes from each WHS to its nearest injection point. By using current parameters results show that small wind farms are not suitable to run electrolysers under available wind operation. They must be run at full capacity to achieve sufficiently low LCOH. At full capacity the future average LCOH is 6–8 €/kg with total hydrogen production capacity of 49 kilotonnes per year or equivalent to nearly 3% of Irish natural gas consumption. This potential will increase significantly due to the projected expansion of installed wind capacity in Ireland from 5 GW in 2020 to 10 GW in 2030

The current greatest challenge that all gas turbine manufactures and users have in front of them for the years to come is the energy transition while reducing CO2 footprint and to contrast climate change. To this aim the introduction of hydrogen as fuel gas (or its blend) is playing a very important role. The benefit from an environmental point of view is undisputed but the presence of hydrogen introduces a series of safety related aspects to be considered for the design of all systems of a gas turbine package. Most of the design standards developed and adopted in the past are based on conventional natural gas however physical properties of hydrogen require to analyze additional aspects or revise the current ones. In this context the design for safety is paramount as it is strongly impacted by the low energy ignition of hydrogen blend fuels. Baker Hughes has built its experience on several sites different Customers and applications currently installed. These gas turbines run with a variety of hydrogen blends with concentration as high as 100% hydrogen. Baker Hughes has achieved several milestones moving from design to experimental set up leveraging the internal infrastructures consolidating design assumptions. In this work the critical aspects such as material selection instrumentation electrical devices and components are discussed in the framework of package safety with the aim to evolve conventional design minimizing the impacts on package configurations.

Methanol can be obtained through CO₂ hydrogenation in a membrane reactor with higher yield or lower pressure than in a conventional packed bed reactor. In this study we explore a new kind of membrane with the potential suitability for such membrane reactors. Silicone–ceramic composite membranes are synthetized and characterized for their capability to selectively remove water from a mixture containing hydrogen CO₂ and water at temperatures typical for methanol synthesis. We show that this membrane can achieve selective permeation of water under such harsh conditions and thus is an alternative candidate for use in membrane reactors for processes where water is one of the products and the yield is limited by thermodynamic equilibrium.

Due to the increasing share of renewable energy sources in the electrical network the focus on decarbonization has extended into other energy sectors. The gas sector is of special interest because it can offer seasonal storage capacity and additional flexibility to the electricity sector. In this paper we present a new simulation method designed for hydrogen-enriched natural gas network simulation. It can handle different gas compositions and is thus able to accurately analyze the impact of hydrogen injections into natural gas pipelines. After describing the newly defined simulation method we demonstrate how the simulation tool can be used to analyze a hydrogen-enriched gas pipeline network. An exemplary co-simulation of coupled power and gas networks shows that hydrogen injections are severely constrained by the gas pipeline network highlighting the importance and necessity of considering different gas compositions in the simulation.

Residues and by-products from vegetables and fruit wholesale markets are suitable for recovery in the form of energy through anaerobic digestion allowing waste recovery and introducing them into the circular economy. This suitability is due to their composition structural characteristics and to the biogas generation process which is stable and without inhibition. However it has been observed that the proportion of methane and the level of degradation of the substrate is low. It is decided to study whether the effect of pretreatments on the substrate is beneficial. Freezing ultrafreezing and lyophilization pretreatments are studied. A characterization of the substrates has been performed the route of action of pretreatment determined and the digestion process studied to calculate the generation of biogas methane hydrogen and the proportions among these. Also a complete analysis of the process has been performed by processing the data with mathematical and statistical methods to obtain disintegration constants and levels of degradation. It has been observed that the three pretreatments have positive effects when increasing the solubility of the substrate increasing porosity and improving the accessibility of microorganisms to the substrate. Generation of gases are greatly increased reaching a methane enrichment of 59.751%. Freezing seems to be the best pretreatment as it increases the biodegradation level the speed of the process and the disintegration constant by 306%.

Recent modeling efforts of non-equilibrium effects in detonations have suggested that hydrogen-based detonations may be affected by vibrational non-equilibrium of the hydrogen and oxygen molecules effects which could explain discrepancies of cell sizes measured experimentally and calculated without relaxation effects. The present study addresses the role of vibrational relaxation in 2H2/O2 detonations by considering two-bath gases argon and helium. These two gases have the same thermodynamic and kinetic effects when relaxation is neglected. However due to the bath gases differences in molecular weight and reduced mass differences which affect the molecular collisions relaxation rates can be changed by approximately 50-70%. Experiments were performed in a narrow channel in mixtures of 2H2/O2/7Ar and 2H2/O2/7He to evaluate the role of the bath gas on detonation cellular structures. The experiments showed differences in velocity deficits and cell sizes for experimental conditions keeping the induction zone length constant in each of the mixtures. These differences were negligible in sensitive mixtures but increased with the increase in velocity deficits while the cell sizes approaching the channel dimensions. Near the limits differences of cell size in two mixtures approached a factor of 2. These differences were however reconciled by accounting for the viscous losses to the tube walls evaluated using a modified version of Mirels' laminar boundary layer theory and generalized Chapman-Jouguet theory for eigenvalue detonations. The experiments suggest that there is an influence of relaxation effects on the cellular structure of detonations which is more sensitive to wall boundary conditions. However the previous works showed that the impact of vibrational non-equilibrium in a mixture of H2/Air is more visible due to the effects of N2 in the air slowest to relax. Previous discrepancies suggested to be indicative of relaxation effects should be reevaluated by the inclusion of wall loss effects.

Steam methane reforming (SMR) process is regarded as a viable option to satisfy the growing demand for hydrogen mainly because of its capability for the mass production of hydrogen and the maturity of the technology. In this study an economically optimal process configuration of SMR is proposed by investigating six scenarios with different design and operating conditions including CO₂ emission permits and CO₂ capture and sale. Of the six scenarios the process configuration involving CO₂ capture and sale is the most economical with an H₂ production cost of $1.80/kg-H₂. A wide range of economic analyses is performed to identify the tradeoffs and cost drivers of the SMR process in the economically optimal scenario. Depending on the CO₂ selling price and the CO₂ capture cost the economic feasibility of the SMR-based H₂ production process can be further improved.

In recent years photocatalytic technology driven by solar energy has been extensively investigated to ease energy crisis and environmental pollution. Nevertheless efficiency and stability of photocatalysts are still unsatisfactory. To address these issues design of advanced photocatalysts is important. Cadmium sulphide (CdS) nanomaterials are one of the promising photocatalysts. Among them hollow-structured CdS featured with enhanced light absorption ability large surface area abundant active sites for redox reactions and reduced diffusion distance of photogenerated carriers reveals a broad application prospect. Herein main synthetic strategies and formation mechanism of hollow CdS photocatalysts are summarized. Besides we comprehensively discuss the current development of hollow-structured CdS nanomaterials in photocatalytic applications including H₂ production CO₂ reduction and pollutant degradation. Finally brief conclusions and perspectives on the challenges and future directions for hollow CdS photocatalysts are proposed.