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Hydrogen Jet Fire from a Thermally Activated Pressure Relief Device (TPRD) from Onboard Storage in a Naturally Ventilated Covered Car Park
Aug 2021
Publication
Hydrogen jet fires from a thermally activated pressure relief device (TPRD) on onboard storage are considered for a vehicle in a naturally ventilated covered car park. Computational Fluid Dynamics was used to predict behaviour of ignited releases from a 70 MPa tank into a naturally ventilated covered car park. Releases through TPRD diameters 3.34 2 and 0.5 mm were studied to understand effect on hazard distances from the vehicle. A vertical release and downward releases at 0° 30° and 45° for TPRD diameters 2 and 0.5 mm were considered accounting for tank blowdown. direction of a downward release was found to significantly contribute to decrease of temperature in a hot cloud under the ceiling. Whilst the ceiling is reached by a jet exceeding 300 °C for a release through a TPRD of 2 mm for inclinations of either 0° 30° or 45° an ignited release through a TPRD of 0.5 mm and angle of 45° did not produce a cloud with a temperature above 300 °C at the ceiling during blowdown. The research findings specifically regarding the extent of the cloud of hot gasses have implications for the design of mechanical ventilation systems.
Pathway to Net Zero Emissions
Oct 2021
Publication
A feasible path to limit planetary warming to 1.5°C requires certain countries and sectors to go below net zero and to do so well before the middle of the century according to new analysis from the authors of the Energy Transition Outlook. DNV’s pathway to net zero says North America and Europe must be carbon neutral by 2042 whereas Indian Subcontinent is set to be a net emitter by 2050 Net zero report says carbon capture storage and use is required as energy production will not be carbon neutral by 2050 Aim to halve emissions by 2030 is out of reach but massive early action is needed if we are to have any chance of reaching a 1.5°C future DNV’s new report “Pathway to Net Zero Emissions” describes a feasible way to limit global warming to 1.5°C Policy makers are set to meet in Glasgow for the COP 26 summit with an eye on achieving zero emissions by 2050. For this to happen North America and Europe must be carbon neutral by 2042 and then carbon negative thereafter according to DNV’s pathway to net zero. The pathway also finds that Greater China must reduce emissions by 98% from 2019 levels by 2050. There are regions that cannot realistically transition completely away from fossil fuels in the same timeframe such as the Indian Subcontinent which will reduce emissions by 64%. Pathway to Net Zero Emissions also lays out the pace at which different industry sectors need to decarbonize. The so-called hard-to-abate sectors will take longer to decarbonize and even if sectors like maritime (-90% CO2 emissions in 2050) and iron and steel production (-82%) scale up the introduction of greener technologies they will still be net emitters by 2050.
Role of the Sulphur Source in the Solvothermal Synthesis of Ag-CdS Photocatalysts: Effects on the Structure and Photoactivity for Hydrogen Production
Dec 2020
Publication
The aim of this work is to study the influence of the sulphur source (elemental sulphur thiourea and L-cysteine) in the solvothermal synthesis of Ag-CdS over its growth structuration and state of Ag and how these changes influence on its photoactivity. The differences in the generation rate of the S2− from the sulphur sources during the solvothermal synthesis determine the nucleation and growth pathways of CdS affecting to the silver state and its incorporation into the CdS lattice. The hydrogen production on Ag-CdS photocatalysts decreases according the sequence: thiourea > elemental sulphur >> L-cysteine. The changes in the photoactivity of Ag-CdS samples are analysed in terms of the differences in the insertion of Ag+ into the CdS lattice the formation of composites between CdS and Ag2S and the formation of CdS crystalline domains with strong confinement effect derived from the different sulphur source used in the solvothermal synthesis
Energy Optimization of a Sulfur-Iodine Thermochemical Nuclear Hydrogen Production Cycle
Dec 2021
Publication
The use of nuclear reactors is a large studied possible solution for thermochemical water splitting cycles. Nevertheless there are several problems that have to be solved. One of them is to increase the efficiency of the cycles. Hence in this paper a thermal energy optimization of a SulfureIodine nuclear hydrogen production cycle was performed by means a heuristic method with the aim of minimizing the energy targets of the heat exchanger network at different minimum temperature differences. With this method four different heat exchanger networks are proposed. A reduction of the energy requirements for cooling ranges between 58.9-59.8% and 52.6-53.3% heating compared to the reference design with no heat exchanger network. With this reduction the thermal efficiency of the cycle increased in about 10% in average compared to the reference efficiency. This improves the use of thermal energy of the cycle.
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.
Precooling Temperature Relaxation Technology in Hydrogen Refueling for Fuel-Cell Vehicles
Aug 2021
Publication
The dissemination of fuel-cell vehicles requires cost reduction of hydrogen refueling stations. The temperature of the supplied hydrogen has currently been cooled to approximately 40 C. This has led to larger equipment and increased electric power consumption. This study achieves a relaxation of the precooling temperature to the 20 C level while maintaining the refueling time. (1) Adoption of an MC formula that can flexibly change the refueling rate according to the precooling temperature. (2) Measurement of thermal capacity of refueling system parts and re-evaluation. Selection from multiple refueling control maps according to the dispenser design (Mathison et al. 2015). (3) Calculation of the effective thermal capacity and reselection of the map in real time when the line is cooled from refueling of the previous vehicle (Mathison and Handa 2015). (4) Addition of maps in which the minimum assumed pressures are 10 and 15 MPa. The new method is named MC Multi Map
Analysis of the Hydrogen Induced Cracking by Means of the Small Punch Test: Effect of the Specimen Geometry and the Hydrogen Pre-Charge Mode
Nov 2018
Publication
This paper presents a simplified procedure to analyse the Hydrogen Induced Cracking (HIC) of structural steels by means of the Small Punch Test (SPT). Two types of notched specimens were used: one with through-thickness lateral notch and another with surface longitudinal notch. The results for conventional specimens were compared with those for hydrogen pre-charged specimens. For this purpose two different methods to introduce hydrogen in the specimens were used: cathodic/electrochemical pre-charging and pressurized gaseous hydrogen pre-charging. The results obtained with both methods are also discussed.
Studies of the Impact of Hydrogen on the Stability of Gaseous Mixtures of THT
Dec 2020
Publication
One of the most important requirements concerning the quality of natural gases guaranteeing their safe use involves providing the proper level of their odorization. This allows for the detection of uncontrolled leakages of gases from gas networks installations and devices. The concentration of an odorant should be adjusted in such a manner that the gas odor in a mixture with air would be noticeable by users (gas receivers). A permanent odor of gas is guaranteed by the stability of the odorant molecule and its resistance to changes in the composition of odorized gases. The article presents the results of experimental research on the impact of a hydrogen additive on the stability of tetrahydrothiophene (THT) mixtures in methane and in natural gas with a hydrogen additive. The objective of the work was to determine the readiness of measurement infrastructures routinely used in monitoring the process of odorizing natural gas for potential changes in its composition. One of the elements of this infrastructure includes the reference mixtures of THT used to verify the correctness of the readings of measurement devices. The performed experimental tests address possible changes in the composition of gases supplied via a distribution network resulting from the introduction of hydrogen. The lack of interaction between hydrogen and THT has been verified indirectly by assessing the stability of its mixtures with methane and natural gas containing hydrogen. The results of the presented tests permitted the identification of potential hazards for the safe use of gas from a distribution network resulting from changes in its composition caused by the addition of hydrogen.
A Statistical Assessment of Blending Hydrogen into Gas Networks
Aug 2021
Publication
The deployment of low-carbon hydrogen in gas grids comes with strategic benefits in terms of energy system integration and decarbonization. However hydrogen thermophysical properties substantially differ from natural gas and pose concerns of technical and regulatory nature. The present study investigates the blending of hydrogen into distribution gas networks focusing on the steady-state fluid dynamic response of the grids and gas quality compliance issues at increasing hydrogen admixture levels. Two blending strategies are analyzed the first of which involves the supply of NG–H2 blends at the city gate while the latter addresses the injection of pure hydrogen in internal grid locations. In contrast with traditional case-specific analyses results are derived from simulations executed over a large number (i.e. one thousand) of synthetic models of gas networks. The responses of the grids are therefore analyzed in a statistical fashion. The results highlight that lower probabilities of violating fluid dynamic and quality restrictions are obtained when hydrogen injection occurs close to or in correspondence with the system city gate. When pure hydrogen is injected in internal grid locations even very low volumes (1% vol of the total) may determine gas quality violations while fluid dynamic issues arise only in rare cases of significant hydrogen injection volumes (30% vol of the total).
Exergy and Exergoeconomic Analysis of Hydrogen and Power Cogeneration Using an HTR Plant
Mar 2021
Publication
This paper proposes using sodium-cooled fast reactor technologies for use in hydrogen vapor methane (SMR) modification. Using three independent energy rings in the Russian BN-600 fast reactor steam is generated in one of the steam-generating cycles with a pressure of 13.1 MPa and a temperature of 505 °C. The reactor's second energy cycles can increase the gas-steam mixture's temperature to the required amount for efficient correction. The 620 ton/hr 540 °C steam generated in this cycle is sufficient to supply a high-temperature synthesis current source (700 °C) which raises the steam-gas mixture's temperature in the reactor. The proposed technology provides a high rate of hydrogen production (approximately 144.5 ton/hr of standard H2) also up to 25% of the original natural gas in line with existing SMR technology for preparing and heating steam and gas mixtures will be saved. Also exergy analysis results show that the plant's efficiency reaches 78.5% using HTR heat for combined hydrogen and power generation.
Construction of Natural Gas Energy-measuring System in China: A Discussion
Feb 2022
Publication
During the 13th Five-Year Plan China's natural gas industry developed rapidly and a diversified supply and marketing pattern was formed including domestic conventional gas unconventional gas (shale gas tight sandstone gas coalbed methane etc.) coal-based synthetic natural gas imported LNG and imported pipeline gas. The gross calorific value of gas sources ranged from 34 MJ/m3 to 43 MJ/m3 and the maximum difference of calorific value between different gas sources exceeded 20%. On May 24th 2019 the National Development and Reform Commission and other three ministries/commissions jointly issued the Supervision Regulation on the Fair Access of Oil and Gas Pipeline Network Facilities and required that a natural gas energy measuring and pricing system shall be established within 24 months from the implementation date of this Regulation. In order to speed up the construction of China's natural gas energy measuring system this paper summarizes domestic achievements in the construction of natural gas energy measuring system from the aspects of value traceability and energy measurement standard and analyzes natural gas flowrate measurement technology calorific value determination technology value traceability localization intelligentization and application technology of key energy measurement equipment natural gas pipeline network energy balancing technology based on big data analysis multi-source quality tracking and monitoring technology and energy measurement standard system the need of new energy detection and measurement technology and put forward strategy for the development of natural gas measuring in China. And the following research results are obtained. First China's natural gas energy measuring system can basically meet the requirements of implementing natural gas energy measurement but it still falls behind the international leading level in terms of calibration and application of high-level flowmeter (such as 0.5 class) high-accuracy gas reference material level of calorific value reference equipment and measurement standard system and needs to be further improved. Second it is necessary for China to speed up the research and application of the localization and intelligentization technologies of key energy measurement equipment. Third natural gas pipeline network shall be equipped with measurement check method energy balancing system based on big data analysis and multi-source quality tracking and monitoring system so that the energy transmission loss index of natural gas pipeline network can be superior to the international leading level (0.10%). Fourth to realize the large-scale application of hydrogen energy and bio-energy and the mixed transportation of hydrogen bio-methane and natural gas it is necessary to carry out research on new technology and standardization of hydrogen/bio-methane blended natural gas detection and measurement.
Fundamentals and Principles of Solid-State Electrochemical Sensors for High Temperature Gas Detection
Dec 2021
Publication
The rapid development of science technology and engineering in the 21st century has offered a remarkable rise in our living standards. However at the same time serious environmental issues have emerged such as acid rain and the greenhouse effect which are associated with the ever-increasing need for energy consumption 85% of which comes from fossil fuels combustion. From this combustion process except for energy the main greenhouse gases-carbon dioxide and steam-are produced. Moreover during industrial processes many hazardous gases are emitted. For this reason gas-detecting devices such as electrochemical gas sensors able to analyze the composition of a target atmosphere in real time are important for further improving our living quality. Such devices can help address environmental issues and inform us about the presence of dangerous gases. Furthermore as non-renewable energy sources run out there is a need for energy saving. By analyzing the composition of combustion emissions of automobiles or industries combustion processes can be optimized. This review deals with electrochemical gas sensors based on solid oxide electrolytes which are employed for the detection of hazardous gasses at high temperatures and aggressive environments. The fundamentals the principle of operation and the configuration of potentiometric amperometric combined (amperometric-potentiometric) and mixed-potential gas sensors are presented. Moreover the results of previous studies on carbon oxides (COx) nitrogen oxides (NOx) hydrogen (H2 ) oxygen (O2 ) ammonia (NH3 ) and humidity (steam) electrochemical sensors are reported and discussed. Emphasis is given to sensors based on oxygen ion and proton-conducting electrolytes.
Stress Corrosion Cracking of Gas Pipeline Steels of Different Strength
Jul 2016
Publication
With the development of the natural gas industry gas transmission pipelines have been developed rapidly in terms of safety economy and efficiency. Our recent studies have shown that an important factor of main pipelines serviceability loss under their long-term service is the in-bulk metal degradation of the pipe wall. This leads to the loss of the initial mechanical properties primarily resistance to brittle fracture which were set in engineering calculations at the pipeline design stage. At the same time stress corrosion cracking has been identified as one of the predominant failures in pipeline steels in humid environments which causes rupture of high-pressure gas transmission pipes as well as serious economic losses and disasters.
In the present work the low-carbon pipeline steels with different strength levels from the point of view of their susceptibility to stress corrosion cracking in the as-received state and after in-laboratory accelerated degradation under environmental conditions similar to those of an acidic soil were investigated. The main objectives of this study were to determine whether the development of higher strength materials led to greater susceptibility to stress corrosion cracking and whether degraded pipeline steels became more susceptible to stress corrosion cracking than in the as-received state. The procedure of accelerated degradation of pipeline steels was developed and introduced in laboratory under the combined action of axial loading and hydrogen charging. It proved to be reliable and useful to performed laboratory simulation of in-service degradation of pipeline steels with different strength. The in-laboratory degraded 17H1S and X60 pipeline steels tested in the NS4 solution saturated with CO2 under open circuit potential revealed the susceptibility to stress corrosion cracking reflected in the degradation of mechanical properties and at the same time the degraded X60 steel showed higher resistance to stress corrosion cracking than the degraded 17H1S steel. Fractographic observation confirmed the pipeline steels hydrogen embrittlement caused by the permeated hydrogen.
In the present work the low-carbon pipeline steels with different strength levels from the point of view of their susceptibility to stress corrosion cracking in the as-received state and after in-laboratory accelerated degradation under environmental conditions similar to those of an acidic soil were investigated. The main objectives of this study were to determine whether the development of higher strength materials led to greater susceptibility to stress corrosion cracking and whether degraded pipeline steels became more susceptible to stress corrosion cracking than in the as-received state. The procedure of accelerated degradation of pipeline steels was developed and introduced in laboratory under the combined action of axial loading and hydrogen charging. It proved to be reliable and useful to performed laboratory simulation of in-service degradation of pipeline steels with different strength. The in-laboratory degraded 17H1S and X60 pipeline steels tested in the NS4 solution saturated with CO2 under open circuit potential revealed the susceptibility to stress corrosion cracking reflected in the degradation of mechanical properties and at the same time the degraded X60 steel showed higher resistance to stress corrosion cracking than the degraded 17H1S steel. Fractographic observation confirmed the pipeline steels hydrogen embrittlement caused by the permeated hydrogen.
Inefficient Investments as a Key to Narrowing Regional Economic Imbalances
Feb 2022
Publication
Policy led decisions aiming at decarbonizing the economy may well exacerbate existing regional economic imbalances. These effects are seldomly recognised in spatially aggregated top-down and techno-economic decarbonization strategies. Here we present a spatial economic framework that quantifies the gross value added associated with low carbon hydrogen investments while accounting for region-specific factors such as the industrial specialization of regions their relative size and their economic interdependencies. In our case study which uses low carbon hydrogen produced via autothermal reforming combined with carbon capture and storage to decarbonize the energy intensive industries in Europe and in the UK we demonstrate that interregional economic interdependencies drive the overall economic benefits of the decarbonization. Policies intended to concurrently transition to net zero and address existing regional imbalances as in the case of the UK Industrial Decarbonization Challenge should take these local factors into account.
Electrified Hydrogen Production from Methane for PEM Fuel Cells Feeding: A Review
May 2022
Publication
The greatest challenge of our times is to identify low cost and environmentally friendly alternative energy sources to fossil fuels. From this point of view the decarbonization of industrial chemical processes is fundamental and the use of hydrogen as an energy vector usable by fuel cells is strategic. It is possible to tackle the decarbonization of industrial chemical processes with the electrification of systems. The purpose of this review is to provide an overview of the latest research on the electrification of endothermic industrial chemical processes aimed at the production of H2 from methane and its use for energy production through proton exchange membrane fuel cells (PEMFC). In particular two main electrification methods are examined microwave heating (MW) and resistive heating (Joule) aimed at transferring heat directly on the surface of the catalyst. For cases the catalyst formulation and reactor configuration were analyzed and compared. The key aspects of the use of H2 through PEM were also analyzed highlighting the most used catalysts and their performance. With the information contained in this review we want to give scientists and researchers the opportunity to compare both in terms of reactor and energy efficiency the different solutions proposed for the electrification of chemical processes available in the recent literature. In particular through this review it is possible to identify the solutions that allow a possible scale-up of the electrified chemical process imagining a distributed production of hydrogen and its consequent use with PEMs. As for PEMs in the review it is possible to find interesting alternative solutions to platinum with the PGM (Platinum Group Metal) free-based catalysts proposing the use of Fe or Co for PEM application.
The Future of Gas in Decarbonising European Energy Markets – The Need for a New Approach
Sep 2017
Publication
The European gas industry has argued that gas can be a bridging fuel in the transition to decarbonised energy markets because of the advantages of switching from coal to gas and the role of gas in backing up intermittent renewable power generation. While this remains a logical approach for some countries in others it has proved either not relevant or generally unsuccessful in gaining acceptance with either policymakers or the environmental community. Policy decisions will be taken in the next 5-10 years which will irreversibly impact the future of gas in the period 2030-50. A paradigm shift in commercial time horizons and gas value chain cooperation will be necessary for the industry to embrace decarbonisation technologies (such as carbon capture and storage) which will eventually be necessary if gas is to prolong its future in European energy markets. To ensure a post-2030 future in European energy balances the gas community will be obliged to adopt a new message: `Gas can Decarbonise’ (and remain competitive with other low/zero carbon energy supplies). It will need to back up this message with a strategy which will lead to the decarbonisation of methane starting no later than 2030. Failure to do so will be to accept a future of decline albeit on a scale of decades and to risk that by the time the community engages with decarbonisation non-methane policy options will have been adopted which will make that decline irreversible.
The Influence of Hydrogen Sulfide Contaminations on Hydrogen Production in Chemical Looping Processes
Aug 2021
Publication
Chemical looping with iron-based oxygen carriers enables the production of hydrogen from various fossil and biogenic primary energy sources. In applications with real producer gases such as biogas or gasified biomass hydrogen sulfide represents one of the most challenging contaminants. The impact of H2S on the reactivity of a Fe2O3/Al2O3 oxygen carrier material in chemical looping hydrogen production was investigated in the present work. First potential sulfur deactivation mechanisms are discussed in detail on the basis of thermodynamic data. Afterwards an experimental study in a fixed-bed reactor system gave experimental evidence on the fate of sulfur in chemical looping hydrogen systems. The chemisorption of hydrogen sulfide (H2S) was identified as the main cause for the accumulative adsorption of H2S in the reduction phase and was confirmed by ex-situ ICP-EOS analysis. In the subsequent steam oxidation step significant quantities of H2S were released resulting in an undesirable contamination of the hydrogen product gas. The reason was found as weakened sulfur bonds through increasing reactor temperatures caused by the exothermic oxidation reactions. In additional air oxidation steps no further contaminants as sulfur dioxide were identified. A profound interpretation was achieved through the fulfillment of the overall sulfur mass balance within a mean deviation of 3.7%. Quantitative investigations showed that the hydrogen consumption decreased by 12% throughout the reduction phase in the event of 100 ppm H2S in the feed gas
The Role of Synthetic Fuels for a Carbon Neutral Economy
Apr 2017
Publication
Fossil fuels depletion and increasing environmental impacts arising from their use call for seeking growing supplies from renewable and nuclear primary energy sources. However it is necessary to simultaneously attend to both the electrical power needs and the specificities of the transport and industrial sector requirements. A major question posed by the shift away from traditional fossil fuels towards renewable energy sources lies in matching the power demand with the daily and seasonal oscillation and the intermittency of these natural energy fluxes. Huge energy storage requirements become necessary or otherwise the decline of the power factor of both the renewable and conventional generation would mean loss of resources. On the other hand liquid and gaseous fuels for which there is vast storage and distribution capacity available appear essential to supply the transport sector for a very long time ahead besides their domestic and industrial roles. Within this context the present assessment suggests that proven technologies and sound tested principles are available to develop an integrated energy system relying on synthetic fuels. These would incorporate carbon capture and utilization in a closed carbon cycle progressively relying mostly on solar and/or nuclear primary sources providing both electric power and gaseous/liquid hydrocarbon fuels having ample storage capacity and able to timely satisfy all forms of energy demand. The principles and means are already available to develop a carbon-neutral synthetic fuel economy.
UK Hydrogen Economy: Debate Pack
Dec 2020
Publication
A Westminster Hall debate on the UK hydrogen economy has been scheduled for Thursday 17 December 2020 at 3.00pm. The debate will be led by Alexander Stafford MP. This House of Commons Library debate pack provides background information and press and parliamentary coverage of the issues.<br/><br/>The Government has legally binding targets under the Climate Change Act 2008 to reach ‘net zero’ carbon emissions by 2050. Background information is available from the Library webpage on Climate Change: an overview.<br/><br/>In order to meet the net zero target the use of fossil fuels (without abatement such as carbon capture usage and storage) across the economy will need to be almost entirely phased out by 2050. Hydrogen gas is regarded as an energy option to help decarbonisation especially in relation to applications that may be more challenging to decarbonise. These applications include heating transport (including heavy goods shipping and aviation) and some industrial processes.<br/><br/>The Government has legally binding targets under the Climate Change Act 2008 to reach ‘net zero’ carbon emissions by 2050. Background information is available from the Library webpage on Climate Change: an overview.<br/><br/>In order to meet the net zero target the use of fossil fuels (without abatement such as carbon capture usage and storage) across the economy will need to be almost entirely phased out by 2050. Hydrogen gas is regarded as an energy option to help decarbonisation especially in relation to applications that may be more challenging to decarbonise. These applications include heating transport (including heavy goods shipping and aviation) and some industrial processes.
Electrification Opportunities in the Medium- and Heavy-Duty Vehicle Segment in Canada
Jun 2021
Publication
The medium- and heavy-duty (MD/HD) vehicle sector is a large emitter of greenhouse gases. It will require drastic emissions reductions to realize a net-zero carbon future. This study conducts fourteen short feasibility investigations in the Canadian context to evaluate the merits of battery electric or hydrogen fuel cell alternatives to conventional city buses inter-city buses school buses courier vehicles (step vans) refuse trucks long-haul trucks and construction vehicles. These “clean transportation alternatives” were evaluated for practicality economics and emission reductions in comparison to their conventional counterparts. Conclusions were drawn on which use cases would be best suited for accelerating the transformation of the MD/HD sector.
Oxford Energy Podcast – Hydrogen in Europe
Apr 2021
Publication
The EU and a number of its member states have now published hydrogen strategies and Europe continues to lead the way in the decarbonisation of its gas sector. In this latest OIES Energy Podcast James Henderson talks with Martin Lambert and Simon Schulte about their latest paper entitled “Contrasting European Hydrogen Pathways” which examines the plans in six major EU countries. They discuss the outlook for various forms of hydrogen supply contrasting the potential for green hydrogen from renewable energy with the outlook for blue hydrogen using steam-reforming of methane as well as hydrogen generated from surplus nuclear energy. They also examine the potential sources of demand considering existing use of hydrogen in industrial processes as well as the potential for hydrogen to displace hydrocarbons in the steel and cement industries. Finally the podcast also looks at the potential for imports of hydrogen and its distribution within Europe while also considering some key milestones that can provide indicators of how the region’s hydrogen plans are playing out.
The podcast can be found on their website
The podcast can be found on their website
Offshore Wind and Hydrogen: Solving the Integration Challenge
Sep 2020
Publication
The combination of offshore wind and green hydrogen provides major opportunities for job creation economic growth and regional regeneration as well as attracting inward investment alongside delivering the emission reductions needed to achieve climate neutrality. In order to get to Net Zero emissions in 2050 the UK is likely to need a minimum of 75GW of offshore wind (OSW) and modelling of the energy system indicates that hydrogen will play a major role in integrating the high levels of OSW on the electricity grid.<br/><br/>Some of the key findings from report are listed below:<br/><br/>The UK has vast resources of offshore wind with the potential for over 600GW in UK waters and potentially up to 1000GW. This is well above the he figure of 75-100GW likely to be needed for UK electricity generation by 2050.<br/>The universities in the UK provide the underpinning science and engineering for electrolysers fuel cells and hydrogen and are home to world-leading capability in these areas.<br/>In order to achieve cost reduction and growing a significant manufacturing and export industry it will be crucial to develop green hydrogen in the next 5 years<br/>By 2050 green hydrogen can be cheaper than blue hydrogen. With accelerated deployment green hydrogen costs can be competitive with blue hydrogen by the eary 2030s.<br/>The combination of additional OSW deployment and electrolyser manufacture alone could generate over 120000 new jobs. These are are expected to be based mainly in manufacturing OSW-related activity shipping and mobility<br/>By 2050 it is estimated that the cumulative gross value added (GVA) from supply of electrolysers and additional OSW farm could be up to £320bn where the majority will come from exports of electrolysers to overseas markets.<br/>The report also calls for immediate government intervention and a new national strategy to support the creation of supply and demand in the new industry.<br/><br/>This study was jointly supported by the Offshore Wind Industry Council (OWIC) and ORE Catapult.
The NederDrone: A Hybrid Lift, Hybrid Energy Hydrogen UAV
Mar 2021
Publication
Many Unmanned Air Vehicle (UAV) applications require vertical take-off and landing and very long-range capabilities. Fixed-wing aircraft need long runways to land and electric energy is still a bottleneck for helicopters which are not range efficient. In this paper we introduce the NederDrone a hybrid lift hybrid energy hydrogen-powered UAV that can perform vertical take-off and landings using its 12 propellers while flying efficiently in forward flight thanks to its fixed wings. The energy is supplied from a combination of hydrogen-driven Polymer Electrolyte Membrane fuel-cells for endurance and lithium batteries for high-power situations. The hydrogen is stored in a pressurized cylinder around which the UAV is optimized. This work analyses the selection of the concept the implemented safety elements the electronics and flight control and shows flight data including a 3h38 flight at sea while starting and landing from a small moving ship.
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
Solar Thermochemical Hydrogen Production in the USA
Jul 2021
Publication
Hydrogen produced from renewable energy has the potential to decarbonize parts of the transport sector and many other industries. For a sustainable replacement of fossil energy carriers both the environmental and economic performance of its production are important. Here the solar thermochemical hydrogen pathway is characterized with a techno-economic and life-cycle analysis. Assuming a further increase of conversion efficiency and a reduction of investment costs it is found that hydrogen can be produced in the United States of America at costs of 2.1–3.2 EUR/kg (2.4–3.6 USD/kg) at specific greenhouse gas emissions of 1.4 kg CO2-eq/kg. A geographical potential analysis shows that a maximum of 8.4 × 1011 kg per year can be produced which corresponds to about twelve times the current global and about 80 times the current US hydrogen production. The best locations are found in the Southwest of the US which have a high solar irradiation and short distances to the sea which is beneficial for access to desalinated water. Unlike for petrochemical products the transport of hydrogen could potentially present an obstacle in terms of cost and emissions under unfavorable circumstances. Given a large-scale deployment low-cost transport seems however feasible.
Understanding Corrosion Morphology of Duplex Stainless Steel Wire in Chloride Electrolyte
Jul 2021
Publication
The corrosion morphology in grade 2205 duplex stainless steel wire was studied to understand the nature of pitting and the causes of the ferrite phase’s selective corrosion in acidic (pH 3) NaCl solutions at 60 °C. It is shown that the corrosion mechanism is always pitting which either manifests lacy cover perforation or densely arrayed selective cavities developing selectively on the ferrite phase. Pits with a lacy metal cover form in concentrated chloride solutions whereas the ferrite phase’s selective corrosion develops in diluted electrolytes showing dependency on the chloride-ion concentration. The pit perforation is probabilistic and occurs on both austenite and ferrite grains. The lacy metal covers collapse in concentrated solutions but remain intact in diluted electrolytes. The collapse of the lacy metal cover happens due to hydrogen embrittlement. Pit evolution is deterministic and occurs selectively in the ferrite phase in light chloride solutions.
The Dawn of Hydrogen - Fuel of the Future
Aug 2021
Publication
This is a time of enormous change for the gas industry as the UK and the world at large attempts to meet the challenges of decarbonisation in the face of climate change. Hydrogen is expected to play a vital role in achieving the government’s commitment of eliminating the UK’s contribution to climate change by 2050 with the industry creating up to 8000 jobs by 2030 and potentially unlocking up to 100000 jobs by the middle of the century. But despite the UK government’s huge ambitions hydrogen is just one piece of the puzzle and it will be necessary to seek solutions that bring the whole energy system together – including not just heat for buildings but hard-to decarbonise areas such as manufacturing road transport aviation and shipping. Here we bring you just a taste of some of the amazing work taking place across the energy sector to understand this fuel more clearly to comprehend its strengths and limitations and to integrate it into our current energy infrastructure. We hope you enjoy this special publication.
Analysis of Stress Corrosion Cracking in X80 Pipeline Steel: An Approach from the Theory of Critical Distances
Dec 2018
Publication
This paper presents an analysis of Stress Corrosion Cracking (SCC) based on the Theory of Critical Distances (TCD). The research is based on an experimental program composed of fracture specimens with notch radius varying from 0 mm (crack-like defect) up to 1 mm and tensile specimens. A pipeline steel was used in this work (X80). It has been analysed in one hydrogen embrittlement situation. The study has been completed with Finite Elements Simulation analysis. The capacity of the TCD to analyse SCC processes has been proven.
Assessment of Full Life-cycle Air Emissions of Alternative Shipping Fuels
Oct 2017
Publication
There is a need for alternative fuels in the shipping sector for two main motivations: to deliver a reduction in local pollutants and comply with existing regulation; and to mitigate climate change and cut greenhouse gas emissions. However any alternative fuel must meet a range of criteria to become a viable option. Key among them is the requirement that it can deliver emissions reductions over its full life-cycle. For a set of fuels comprising both conventional and alternative fuels together with associated production pathways this paper presents a life-cycle assessment with respect to six emissions species: local pollutants sulphur oxides nitrogen oxides and particulate matter; and greenhouse gases carbon dioxide methane and nitrous oxide. While the analysis demonstrates that no widely available fuel exists currently to deliver on both motivations some alternative fuel options have the potential if key barriers can be overcome. Hydrogen or other synthetic fuels rely on decarbonisation of both energy input to production and other feedstock materials to deliver reductions in greenhouse gas emissions. Similarly bio-derived fuels can be an abatement option but only if it can be ensured that land-use change whilst growing biomass does not impact wider potential savings and the sector is able to compete sufficiently for their use. These examples show that crucial barriers are located upstream in the respective fuel life-cycle and that the way to overcome them may reside beyond the scope of the shipping sector alone.
A Fracture Analysis of Ti-10Mo-8V-1Fe-3.5Al Alloy Screws during Assembly
Oct 2016
Publication
Titanium screws have properties that make them ideal for applications that require both a high strength-to-weight ratio and corrosion resistance such as fastener applications for aviation and aerospace. The fracture behavior of Ti-10Mo-8V-1Fe-3.5Al (TB3) alloy screws during assembly was explored. Besides visual examination other experimental techniques used for the investigation are as follows: (1) fracture characteristics and damage morphology via scanning electron microscopy (SEM); (2) chemical constituents via energy dispersive spectroscopy (EDS) and hydrogen concentration testing; (3) metallographic observation; (4) stress durability embrittlement testing; and (5) torsion simulation testing. Results show that the fracture mode of the screws is brittle. There is no obvious relation to hydrogen-induced brittle. The main reason for the fracture of titanium alloy screws is internal defects around which oxygen content is high increasing brittleness. The internal defects of screws result from grain boundary cracking caused by hot forging.
FPGA-Based Implementation of an Optimization Algorithm to Maximize the Productivity of a Microbial Electrolysis Cell
Jun 2021
Publication
In this work the design of the hardware architecture to implement an algorithm for optimizing the Hydrogen Productivity Rate (HPR) in a Microbial Electrolysis Cell (MEC) is presented. The HPR in the MEC is maximized by the golden section search algorithm in conjunction with a super-twisting controller. The development of the digital architecture in the implementation step of the optimization algorithm was developed in the Very High Description Language (VHDL) and synthesized in a Field Programmable Gate Array (FPGA). Numerical simulations demonstrated the feasibility of the proposed optimization strategy embedded in an FPGA Cyclone II. Results showed that only.
Zero-Emission Pathway for the Global Chemical and Petrochemical Sector
Jun 2021
Publication
The chemical and petrochemical sector relies on fossil fuels and feedstocks and is a major source of carbon dioxide (CO2 ) emissions. The techno-economic potential of 20 decarbonisation options is assessed. While previous analyses focus on the production processes this analysis covers the full product life cycle CO2 emissions. The analysis elaborates the carbon accounting complexity that results from the non-energy use of fossil fuels and highlights the importance of strategies that consider the carbon stored in synthetic organic products—an aspect that warrants more attention in long-term energy scenarios and strategies. Average mitigation costs in the sector would amount to 64 United States dollars (USD) per tonne of CO2 for full decarbonisation in 2050. The rapidly declining renewables cost is one main cause for this low-cost estimate. Renewable energy supply solutions in combination with electrification account for 40% of total emissions reductions. Annual biomass use grows to 1.3 gigatonnes; green hydrogen electrolyser capacity grows to 2435 gigawatts and recycling rates increase six-fold while product demand is reduced by a third compared to the reference case. CO2 capture storage and use equals 30% of the total decarbonisation effort (1.49 gigatonnes per year) where about one-third of the captured CO2 is of biogenic origin. Circular economy concepts including recycling account for 16% while energy efficiency accounts for 12% of the decarbonisation needed. Achieving full decarbonisation in this sector will increase energy and feedstock costs by more than 35%. The analysis shows the importance of renewables-based solutions accounting for more than half of the total emissions reduction potential which was higher than previous estimates.
Business Energy and Industrial Strategy Committee Inquiry into Decarbonising Heat in Homes
Dec 2020
Publication
The Hydrogen Taskforce welcomes the opportunity to submit evidence to the Business Energy and Industrial Strategy Committee’s inquiry into decarbonising heat in homes. It is the Taskforce’s view that:
In March 2020 the Taskforce has defined a set of policy recommendations for Government which are designed to ensure that hydrogen can scale to meet the future demands of a net zero energy system: • Development of a cross departmental UK Hydrogen Strategy within UK Government;• Commit £1bn of capex funding over the next spending review period to hydrogen production storage and distribution projects;• Develop a financial support scheme for the production of hydrogen in blending industry power and transport.• Amend Gas Safety Management Regulations (GSMR) to enable hydrogen blending and take the next steps towards 100% hydrogen heating through supporting public trials and mandating 100% hydrogen-ready boilers by 2025; and• Commit to the support of 100 Hydrogen Refuelling Stations (HRS) by 2025 to support the rollout of hydrogen transport.
You can download the whole document from the Hydrogen Taskforce website here
- Decarbonising heat is one of the biggest challenges that the UK faces in meeting Net Zero and several solutions will be required;
- Hydrogen can play a valuable role in reducing the cost of decarbonising heat. Its high energy density enables it to be stored cost effectively at scale providing system resilience;
- Hydrogen heating can be implemented at minimal disruption to the consumer;
- The UK holds world-class advantages in hydrogen production distribution and application; and
- Other economies are moving ahead in the development of this sector and the UK must respond.
In March 2020 the Taskforce has defined a set of policy recommendations for Government which are designed to ensure that hydrogen can scale to meet the future demands of a net zero energy system: • Development of a cross departmental UK Hydrogen Strategy within UK Government;• Commit £1bn of capex funding over the next spending review period to hydrogen production storage and distribution projects;• Develop a financial support scheme for the production of hydrogen in blending industry power and transport.• Amend Gas Safety Management Regulations (GSMR) to enable hydrogen blending and take the next steps towards 100% hydrogen heating through supporting public trials and mandating 100% hydrogen-ready boilers by 2025; and• Commit to the support of 100 Hydrogen Refuelling Stations (HRS) by 2025 to support the rollout of hydrogen transport.
You can download the whole document from the Hydrogen Taskforce website here
Pathways toward a Decarbonized Future—Impact on Security of Supply and System Stability in a Sustainable German Energy System
Jan 2021
Publication
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.
Controllable H2 Generation by Formic Acid Decomposition on a Novel Pd/Templated Carbon Catalyst
Nov 2020
Publication
A novel Pd/templated carbon catalyst (Pd/TC) was developed characterized and tested in the dehydrogenation of formic acid (FA) under mild conditions with the possibility to control the H2 generation rate in the absence or presence of HCOONa (SF) by adjusting the Pd:FA and/or FA:SF ratios. The characterization results of the templated carbon obtained by the chemical vapor deposition of acetylene on NaY zeolite revealed different structural and morphological properties compared to other C-based supports. Therefore it was expected to induce a different catalytic behavior for the Pd/TC catalyst. Indeed the TC-supported Pd catalyst exhibited superior activity in the decomposition of FA even at room temperature with turnover frequencies (TOFs) of up to 143.7 and 218.8 h−1 at 60 °C. The H2 generation rate increased with an increasing temperature while the H2 yield increased with a decreasing FA concentration. Constant generation of gaseous flow (H2 + CO2) was achieved for 11 days by the complete dehydrogenation of FA at room temperature using a 2 M FA solution and Pd:FA = 1:2100. The presence of SF in the reaction medium significantly enhanced the H2 generation rate (535 h−1 for FA:SF = 3:1 and 60 °C).
Hollow Cobalt Sulfide Nanocapsules for Electrocatalytic Selective Transfer Hydrogenation of Cinnamaldehyde with Water
Feb 2021
Publication
Designing nanostructured electrocatalysts for selective transfer hydrogenation of α β-unsaturated aldehydes with water as the hydrogen source is highly desirable. Here a facile self-templating strategy is designed for the synthesis of CoS2 and CoS2-x nanocapsules (NCs) as efficient cathodes for selective transfer hydrogenation of cinnamaldehyde a model α β-unsaturated aldehyde. The hollow porous structures of NCs are rich in active sites and improve mass transfer resulting in high turnover frequency. The specific adsorption of the styryl block on pristine CoS2 NCs is conducive to the selective formation of half-hydrogenated hydrocinnamaldehyde with 91.7% selectivity and the preferential adsorption of the C = O group induced by sulfur vacancies on defective CoS2-x NCs leads to the full-hydrogenated hydrocinnamyl alcohol with 92.1% selectivity. A cross-coupling of carbon and hydrogen radicals may be involved in this electrochemical hydrogenation reaction. Furthermore this selective hydrogenation method is also effective for other α β-unsaturated aldehydes illustrating the universality of the method.
Optimal Hydrogen Production in a Wind-dominated Zero-emission Energy System
May 2021
Publication
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.
Engineering a Sustainable Gas Future
Nov 2021
Publication
The Institution of Gas Engineers & Managers (IGEM) is the UK’s Professional Engineering Institution supporting individuals and businesses working in the global gas industry. IGEM was founded in 1863 with the purpose of advancing the science and relevant knowledge of gas engineering for the benefit of the public.
As a not-for-profit independent organisation IGEM acts as a trusted source of technical information guidance and services for the gas sector. In today’s net zero context IGEM is focused on engineering a sustainable gas future – we do this by:
This document outlines the current UK gas policy landscape our stance and what contribution we are making as an organisation.
As a not-for-profit independent organisation IGEM acts as a trusted source of technical information guidance and services for the gas sector. In today’s net zero context IGEM is focused on engineering a sustainable gas future – we do this by:
- Helping our members achieve and uphold the highest standards of professional competence to ensure the safety of the public
- Supporting our members in achieving their career goals by providing high quality products services and personal and professional development opportunities
- Acting as the voice of the gas industry when working with stakeholders to develop and improve gas policy.
This document outlines the current UK gas policy landscape our stance and what contribution we are making as an organisation.
Testing Programme for Hydrogen Tolerance Tests of Domestic and Commercial Natural Gas Appliances
Jan 2021
Publication
The THyGA project (‘Testing Hydrogen admixture for Gas Applications’) focusses on technical aspects and the regulatory framework concerning the potential operation of domestic and commercial end-user appliances with hydrogen / natural gas blends.<br/>The core of the project is a broad experimental campaign with the aim to conduct up to 100 hydrogen tolerance tests. In addition the technical status quo and present knowledge about hydrogen impact on domestic and commercial appliances are assessed and potential future developments of rules and standards are discussed. Also mitigation strategies for coping with high levels of hydrogen admixture will be developed. By this broad approach the project aims at investigating which levels of hydrogen blending impact the various appliance technologies and to which extent in order to identify the regime in which a safe efficient and low-polluting operation is possible.<br/>The series of public reports by the THyGA project starts with several publications from work package 2 which sets the basis for the upcoming results and discussion of the experimental campaign as well as mitigation and standardisation topics.<br/>This report D2.5 completes the series of public reports from work package 2. It explains the steps of development of the test programme for gas-fired appliance tests with hydrogen admixture and especially describes the exchange between the THyGA partners and the external stakeholders.<br/>The report also explains the process of acquisition of appliances to test and method of selecting appliances.
Impacts of Variation Management on Cost-optimal Investments in Wind Power and Solar Photovoltaics
Dec 2019
Publication
This work investigates the impacts of variation management on the cost-optimal electricity system compositions in four regions with different pre-requisites for wind and solar generation. Five variation management strategies involving electric boilers batteries hydrogen storage low-cost biomass and demand-side management are integrated into a regional investment model that is designed to account for variability. The variation management strategies are considered one at a time as well as combined in four different system contexts. By investigating how the variation management strategies interact with each other as well as with different electricity generation technologies in a large number of cases this work support policy-makers in identifying variation management portfolios relevant to their context. It is found that electric boilers demand-side management and hydrogen storage increase the cost-optimal variable renewable electricity (VRE) investments if the VRE share is sufficiently large to reduce its marginal system value. However low-cost biomass and hydrogen storage are found to increase cost-optimal investments in wind power in systems with a low initial wind power share. In systems with low solar PV share variation management reduce the cost-optimal solar PV investments. In two of the regions investigated a combination of variation management strategies results in a stronger increase in VRE capacity than the sum of the single variation management efforts.
NanoSIMS Analysis of Hydrogen and Deuterium in Metallic Alloys: Artefacts and Best Practice
Apr 2021
Publication
Hydrogen embrittlement can cause catastrophic failure of high strength alloys yet determining localised hydrogen in the microstructure is analytically challenging. NanoSIMS is one of the few techniques that can map hydrogen and deuterium in metal samples at microstructurally relevant length scales. Therefore it is essential to understand the artefacts and determine the optimum methodology for its reliable detection. An experimental methodology/protocol for NanoSIMS analysis of deuterium (as a proxy for hydrogen) has been established uncovering unreported artefacts and a new approach is presented to minimise these artefacts in mapping hydrogen and deuterium in alloys. This method was used to map deuterium distributions in electrochemically charged austenitic stainless steel and precipitation hardened nickel-based alloys. Residual deuterium contamination was detected in the analysis chamber as a result of deuterium outgassing from the samples and the impact of this deuterium contamination was assessed by a series of NanoSIMS experiments. A new analysis protocol was developed that involves mapping deuterium in the passive oxide layer thus mitigating beam damage effects that may prevent the detection of localised deuterium signals when the surface is highly deuterated.
Recent Advances in Seawater Electrolysis
Jan 2022
Publication
Hydrogen energy as a clean and renewable energy has attracted much attention in recent years. Water electrolysis via the hydrogen evolution reaction at the cathode coupled with the oxygen evolution reaction at the anode is a promising method to produce hydrogen. Given the shortage of freshwater resources on the planet the direct use of seawater as an electrolyte for hydrogen production has become a hot research topic. Direct use of seawater as the electrolyte for water electrolysis can reduce the cost of hydrogen production due to the great abundance and wide availability. In recent years various high-efficiency electrocatalysts have made great progress in seawater splitting and have shown great potential. This review introduces the mechanisms and challenges of seawater splitting and summarizes the recent progress of various electrocatalysts used for hydrogen and oxygen evolution reaction in seawater electrolysis in recent years. Finally the challenges and future opportunities of seawater electrolysis for hydrogen and oxygen production are presented.
Decarbonization in Shipping Industry: A Review of Research, Technology Development, and Innovation Proposals
Apr 2021
Publication
This review paper examines the possible pathways and possible technologies available that will help the shipping sector achieve the International Maritime Organization’s (IMO) deep decarbonization targets by 2050. There has been increased interest from important stakeholders regarding deep decarbonization evidenced by market surveys conducted by Shell and Deloitte. However deep decarbonization will require financial incentives and policies at an international and regional level given the maritime sector’s ~3% contribution to green house gas (GHG) emissions. The review paper based on research articles and grey literature discusses technoeconomic problems and/or benefits for technologies that will help the shipping sector achieve the IMO’s targets. The review presents a discussion on the recent literature regarding alternative fuels (nuclear hydrogen ammonia methanol) renewable energy sources (biofuels wind solar) the maturity of technologies (fuel cells internal combustion engines) as well as technical and operational strategies to reduce fuel consumption for new and existing ships (slow steaming cleaning and coating waste heat recovery hull and propeller design). The IMO’s 2050 targets will be achieved via radical technology shift together with the aid of social pressure financial incentives regulatory and legislative reforms at the local regional and international level.
Hydrogen-based Integrated Energy and Mobility System for a Real-life Office Environment
Mar 2020
Publication
The current focus on the massive CO2 reduction highlights the need for the rapid development of technology for the production storage transportation and distribution of renewable energy. In addition to electricity we need other forms of energy carriers that are more suitable for energy storage and transportation. Hydrogen is one of the main candidates for this purpose since it can be produced from solar or wind energy and then stored; once needed it can be converted back to electricity using fuel cells. Another important aspect of future energy systems is sector coupling where different sectors e.g. mobility and energy work together to provide better services. In such an integrated system electric vehicles – both battery and hydrogen-based fuel cell – can provide when parked electricity services such as backup power and balancing; when driving they produce no emissions. In this paper we present the concept design and energy management of such an integrated energy and mobility system in a real-life environment at the Shell Technology Centre in Amsterdam. Our results show that storage using hydrogen and salt caverns is much cheaper than using large battery storage systems. We also show that the integration of electric vehicles into the electricity network is technically and economically feasible and that they can provide a flexible energy buffer. Ultimately the results of this study show that using both electricity and hydrogen as energy carriers can create a more flexible reliable and cheaper energy system at an office building.
A Preliminary Energy Analysis of a Commercial CHP Fueled with H2NG Blends Chemically Supercharged by Renewable Hydrogen and Oxygen
Dec 2016
Publication
Currently Power-to-Gas technologies are considered viable solutions to face the onset problems associated with renewable capacity firming. Indeed carbon-free hydrogen production converting renewable electricity excess and its injection into natural gas pipelines is considered a short- to medium-term solution. In this way the so-called H2NG blends can be fired within internal combustion engines and micro gas turbines operating in CHP mode offering better environmental-energy performances in machines. As regards the distributed energy generation scenario the local H2 production by means of electrolysis for methane enrichment will be more cost-effective if the oxygen is fruitfully used instead of venting it out like a by-product as usually occurs. This study focuses on the usefulness of using that oxygen to enrich the air-fuel mixture of an internal combustion engine for micro-CHP applications once it has been fuelled with H2NG blends. Thus the main aim of this paper is to provide a set of values for benchmarking in which H2NG blends ranging in 0%-15% vol. burn within an ICE in partial oxy-fuel conditions. In particular a preliminary energy analysis was carried out based on experimental data reporting the engine operating parameters gains and losses in both electrical and heat recovery efficiency. The oxygen content in the air varies up to 22% vol. A Volkswagen Blue Tender CHP commercial version (19.8 kWel. of rated electrical power output) was considered as the reference machine and its energy characterization was reported when it operated under those unconventional conditions.
Hydrogen-Based Energy Storage Systems for Large-Scale Data Center Applications
Nov 2021
Publication
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.
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.
Alberta Hydrogen Roadmap
Nov 2021
Publication
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.
Hydrogen Mobility Europe (H2ME): Vehicle and Hydrogen Refuelling Station Deployment Results
May 2018
Publication
Hydrogen Mobility Europe (H2ME 2015–2022) is the largest European Fuel Cells and Hydrogen Joint Undertaking (EU FCH JU)-funded hydrogen light vehicle and infrastructure demonstration. Up until April 2017 the 40 Daimler passenger car fuel cell electric vehicles (FCEVs) and 62 Symbio Fuel Cell-Range Extended Electric Vans (FC-REEV)-vans deployed by the project drove 625300 km and consumed a total of 7900 kg of hydrogen with no safety incidents. During its first year of operation (to April 2017) the NEL Hydrogen Fueling HRS (hydrogen refuelling station) in Kolding Denmark dispensed 900 kg of hydrogen and demonstrated excellent reliability (98.2% availability) with no safety incidents. The average hydrogen refuelling time for passenger cars is comparable to that for conventional vehicles (2–3 min).
Fire Safety of Hydrogen-Fuelled Vehicles- System-Level Bonfire Test
Sep 2005
Publication
The European Community requires a vehicle-level bonfire test for vehicles using plastic fuel tanks for conventional fuels (ECE R-34 Annex 5). A similar test could be applied to hydrogen-fuelled vehicles. It would test a realistic vehicle with its complete fuel and safety systems. An advantage of such a test is that the same test could be applied independent of the hydrogen storage technology (compressed gas liquid or hydride). There are currently standards for bonfire testing of a bare Compressed Natural Gas (CNG) tank and its Pressure Relief Device (PRD). This standard is FMVSS 304 in the U.S. and ISO 15869-1 in Europe. Japan has a similar standard. It requires that a bare tank and its associated PRD be subjected to a propane flame for 20 minutes. The tank must either survive or safely vent its contents. No modern composite wound tank is expected to survive for 20 minutes – so this is not a tank test but really a PRD test. The test procedure requires the PRD to be shielded from direct impingement of the flames – but the shield is not well specified. If it shields the PRD too well the PRD will not activate and the tank will burst. This paper describes the results of a CNG and a hydrogen tank burst from such tests. The mechanical energy released is enormous. It is simply unacceptable to allow the tank to burst – the PRD and venting system must work. Organizations in the U.S Europe and Japan are in the process of modifying the CNG tank bonfire test for compressed hydrogen storage. A bare tank with a single PRD is not a good simulation of a hydrogen fuel system installed in an actual vehicle. There will usually be multiple tanks plumbed together at either the tank pressure or at the intermediate pressure (after the pressure regulator). There may be more than one PRD. The tank may be shielded (from debris) or insulated to protect it from an underbody pool fire. Also the heat transfer from the simulated pool fire (propane flame) will be very different when mounted in a vehicle versus the bare tank test. A vehicle-level pool fire test will alleviate these problems. It is therefore recommended that the bare tank test be replaced by or augmented with a vehicle-level bonfire test similar to ECE R-34 Annex 5.
Enhanced Hydrogen Generation from Hydrolysis of MgLi Doped with Expanded Graphite
Apr 2021
Publication
Hydrolysis of Mg-based materials is considered as a potential means of safe and convenient real-time control of H2 release enabling efficient loading discharge and utilization of hydrogen in portable electronic devices. At present work the hydrogen generation properties of MgLi-graphite composites were evaluated for the first time. The MgLi-graphite composites with different doping amounts of expanded graphite (abbreviated as EG hereinafter) were synthesized through ball milling and the hydrogen behaviors of the composites were investigated in chloride solutions. Among the above doping systems the 10 wt% EG-doped MgLi exhibited the best hydrogen performance in MgCl2 solutions. In particular the 22 h-milled MgLi-10 wt% EG composites possessed both desirable hydrogen conversion and rapid reaction kinetics delivering a hydrogen yield of 966 mL H2 g−1 within merely 2 min and a maximum hydrogen generation rate of 1147 mL H2 min−1 g−1 as opposed to the sluggish kinetics in the EG-free composites. Moreover the EG-doped MgLi showed superior air-stable ability even under a 75 RH% ambient atmosphere. For example the 22 h-milled MgLi-10 wt% EG composites held a fuel conversion of 89% after air exposure for 72 h rendering it an advantage for Mg-based materials to safely store and transfer in practical applications. The similar favorable hydrogen performance of MgLi-EG composites in (simulate) seawater may shed light on future development of hydrogen generation technologies.
The Role of Natural Gas and its Infrastructure in Mitigating Greenhouse Gas Emissions, Improving Regional Air Quality, and Renewable Resource Integration
Nov 2017
Publication
The pursuit of future energy systems that can meet electricity demands while supporting the attainment of societal environment goals including mitigating climate change and reducing pollution in the air has led to questions regarding the viability of continued use of natural gas. Natural gas use particularly for electricity generation has increased in recent years due to enhanced resource availability from non-traditional reserves and pressure to reduce greenhouse gasses (GHG) from higher-emitting sources including coal generation. While lower than coal emissions current natural gas power generation strategies primarily utilize combustion with higher emissions of GHG and criteria pollutants than other low-carbon generation options including renewable resources. Furthermore emissions from life cycle stages of natural gas production and distribution can have additional detrimental GHG and air quality (AQ) impacts. On the other hand natural gas power generation can play an important role in supporting renewable resource integration by (1) providing essential load balancing services and (2) supporting the use of gaseous renewable fuels through the existing infrastructure of the natural gas system. Additionally advanced technologies and strategies including fuel cells and combined cooling heating and power (CCHP) systems can facilitate natural gas generation with low emissions and high efficiencies. Thus the role of natural gas generation in the context of GHG mitigation and AQ improvement is complex and multi-faceted requiring consideration of more than simple quantification of total or net emissions. If appropriately constructed and managed natural gas generation could support and advance sustainable and renewable energy. In this paper a review of the literature regarding emissions from natural gas with a focus on power generation is conducted and discussed in the context of GHG and AQ impacts. In addition a pathway forward is proposed for natural gas generation and infrastructure to maximize environmental benefits and support renewable resources in the attainment of emission reductions.
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.
Indicative Analysis of Blending Hydrogen in Gas Networks
May 2020
Publication
Frontier Economics has been engaged by the Commonwealth Department of the Environment and Energy (now Industry Science Energy and Resources) (the Department) to undertake an indicative analysis of the economics of blending hydrogen in Australian natural gas distribution networks. Our analysis is limited to a specific gas distribution network servicing urban areas of Melbourne.
We have investigated the economics of blending hydrogen in a natural gas distribution network by examining a number of energy supply options including options that involve blending hydrogen. While we consider that these cases we have examined are useful for understanding the economics of hydrogen blending at low rates in Victoria and for understanding the factors that are likely to drive the economics of blending at higher rates or in other regions it cannot be assumed that the results we find for the cases we investigate will necessarily apply in other regions or for blending at other rates. This report should be read as an assessment of the specific cases we have investigated and our findings cannot necessarily be extended to other cases (such as other locations or other rates of blending)"
The full report can be found via the website of the Australian government at this link
We have investigated the economics of blending hydrogen in a natural gas distribution network by examining a number of energy supply options including options that involve blending hydrogen. While we consider that these cases we have examined are useful for understanding the economics of hydrogen blending at low rates in Victoria and for understanding the factors that are likely to drive the economics of blending at higher rates or in other regions it cannot be assumed that the results we find for the cases we investigate will necessarily apply in other regions or for blending at other rates. This report should be read as an assessment of the specific cases we have investigated and our findings cannot necessarily be extended to other cases (such as other locations or other rates of blending)"
The full report can be found via the website of the Australian government at this link
Towards the Hydrogen Economy—A Review of the Parameters That Influence the Efficiency of Alkaline Water Electrolyzers
May 2021
Publication
Environmental issues make the quest for better and cleaner energy sources a priority. Worldwide researchers and companies are continuously working on this matter taking one of two approaches: either finding new energy sources or improving the efficiency of existing ones. Hydrogen is a well-known energy carrier due to its high energy content but a somewhat elusive one for being a gas with low molecular weight. This review examines the current electrolysis processes for obtaining hydrogen with an emphasis on alkaline water electrolysis. This process is far from being new but research shows that there is still plenty of room for improvement. The efficiency of an electrolyzer mainly relates to the overpotential and resistances in the cell. This work shows that the path to better electrolyzer efficiency is through the optimization of the cell components and operating conditions. Following a brief introduction to the thermodynamics and kinetics of water electrolysis the most recent developments on several parameters (e.g. electrocatalysts electrolyte composition separator interelectrode distance) are highlighted.
Evaluation of Corrosion, Mechanical Properties and Hydrogen Embrittlement of Casing Pipe Steels with Different Microstructure
Dec 2021
Publication
In the research the corrosion and mechanical properties as well as susceptibility to hydrogen embrittlement of two casing pipe steels were investigated in order to assess their serviceability in corrosive and hydrogenating environments under operation in oil and gas wells. Two carbon steels with different microstructures were tested: the medium carbon steel (MCS) with bainitic microstructure and the medium-high carbon steel (MHCS) with ferrite–pearlite microstructure. The results showed that the corrosion resistance of the MHCS in CO2-containing acid chloride solution simulating formation water was significantly lower than that of the MCS which was associated with microstructure features. The higher strength MCS with the dispersed microstructure was less susceptible to hydrogen embrittlement under preliminary electrolytic hydrogenation than the lower strength MHCS with the coarse-grained microstructure. To estimate the embrittlement of steels the method of the FEM load simulation of the specimens with cracks was used. The constitutive relations of the true stress–strain of the tested steels were defined. The stress and strain dependences in the crack tip were calculated. It was found that the MHCS was characterized by the lower plasticity on the stage of the neck formation of the specimen and the lower fracture toughness than the other one. The obtained results demonstrating the limitations of the usage of casing pipes made of the MHCS with the coarse-grained ferrite/pearlite microstructure in corrosive and hydrogenating environments were discussed.
Risk Assessment Method Combining Independent Protection Layers (IPL) of Layer of Protection Analysis (LOPA) and RISKCURVES Software: Case Study of Hydrogen Refueling Stations in Urban Areas
Jul 2021
Publication
The commercialization of eco-friendly hydrogen vehicles has elicited attempts to expand hydrogen refueling stations in urban areas; however safety measures to reduce the risk of jet fires have not been established. The RISKCURVES software was used to evaluate the individual and societal risks of hydrogen refueling stations in urban areas and the F–N (Frequency–Number of fatalities) curve was used to compare whether the safety measures satisfied international standards. From the results of the analysis it was found that there is a risk of explosion in the expansion of hydrogen refueling stations in urban areas and safety measures should be considered. To lower the risk of hydrogen refueling stations this study applied the passive and active independent protection layers (IPLs) of LOPA (Layer of Protection Analysis) and confirmed that these measures significantly reduced societal risk as well as individual risk and met international standards. In particular such measures could effectively reduce the impact of jet fire in dispensers and tube trailers that had a high risk. Measures employing both IPL types were efficient in meeting international standard criteria; however passive IPLs were found to have a greater risk reduction effect than active IPLs. The combination of RISKCURVES and LOPA is an appropriate risk assessment method that can reduce work time and mitigate risks through protective measures compared to existing risk assessment methods. This method can be applied to risk assessment and risk mitigation not only for hydrogen facilities but also for hazardous materials with high fire or explosion risk.
Interaction of Hydrogen Infrastructures with other Sector Coupling Options Towards a Zero-emission Energy System in Germany
Aug 2021
Publication
The flexible coupling of sectors in the energy system for example via battery electric vehicles electric heating or electric fuel production can contribute significantly to the integration of variable renewable electricity generation. For the implementation of the energy system transformation however there are numerous options for the design of sector coupling each of which is accompanied by different infrastructure requirements. This paper presents the extension of the REMix energy system modelling framework to include the gas sector and its application for investigating the cost-optimal design of sector coupling in Germany's energy system. Considering an integrated optimisation of all relevant technologies in their capacities and hourly use a path to a climate-neutral system in 2050 is analysed. We show that the different options for flexible sector coupling are all needed and perform different functions. Even though flexible electrolytic production of hydrogen takes on a very dominant role in 2050 it does not displace other technologies. Hydrogen also plays a central role in the seasonal balancing of generation and demand. Thus large-scale underground storage is part of the optimal system in addition to a hydrogen transport network. These results provide valuable guidance for the implementation of the energy system transformation in Germany.
Thermodynamic Analysis of Hydrogen Production via Chemical Looping Steam Methane Reforming Coupled with In Situ CO2 Capture
Dec 2014
Publication
A detailed thermodynamic analysis of the sorption enhanced chemical looping reforming of methane (SE-CL-SMR) using CaO and NiO as CO2 sorbent and oxygen transfer material (OTM) respectively was conducted. Conventional reforming (SMR) and sorption enhanced reforming (SE-SMR) were also investigated for comparison reasons. The results of the thermodynamic analysis show that there are significant advantages of both sorption enhanced processes compared to conventional reforming. The presence of CaO leads to higher methane conversion and hydrogen purity at low temperatures. Addition of the OTM in the SECL-SMR process concept minimizes the thermal requirements and results in superior performance compared to SE-SMR and SMR in a two-reactor concept with use of pure oxygen as oxidant/sweep gas.
Recent Advances in Carbon Dioxide Conversion: A Circular Bioeconomy Perspective
Jun 2021
Publication
Managing the concentration of atmospheric CO2 requires a multifaceted engineering strategy which remains a highly challenging task. Reducing atmospheric CO2 (CO2R) by converting it to value-added chemicals in a carbon neutral footprint manner must be the ultimate goal. The latest progress in CO2R through either abiotic (artificial catalysts) or biotic (natural enzymes) processes is reviewed herein. Abiotic CO2R can be conducted in the aqueous phase that usually leads to the formation of a mixture of CO formic acid and hydrogen. By contrast a wide spectrum of hydrocarbon species is often observed by abiotic CO2R in the gaseous phase. On the other hand biotic CO2R is often conducted in the aqueous phase and a wide spectrum of value-added chemicals are obtained. Key to the success of the abiotic process is understanding the surface chemistry of catalysts which significantly governs the reactivity and selectivity of CO2R. However in biotic CO2R operation conditions and reactor design are crucial to reaching a neutral carbon footprint. Future research needs to look toward neutral or even negative carbon footprint CO2R processes. Having a deep insight into the scientific and technological aspect of both abiotic and biotic CO2R would advance in designing efficient catalysts and microalgae farming systems. Integrating the abiotic and biotic CO2R such as microbial fuel cells further diversifies the spectrum of CO2R.
Integration of a Dark Fermentation Effluent in a Microalgal-based Biorefinery for the Production of High-added Value Omega-3 Fatty Acids
Mar 2019
Publication
Dark fermentation is an anaerobic digestion process of biowaste used to produce hydrogen- for generation of energy- that however releases high amounts of polluting volatile fatty acids such as acetic acid in the environment. In order for this biohydrogen production process to become more competitive the volatile fatty acids stream can be utilized through conversion to high added-value metabolites such as omega-3 fatty acids. The docosahexaenoic acid is one of the two most known omega-3 fatty acids and has been found to be necessary for a healthy brain and proper cardiovascular function. The main source is currently fish which obtain the fatty acid from the primary producers microalgae through the food chain. Crypthecodinium cohnii a heterotrophic marine microalga is known for accumulating high amounts of docosahexaenoic acid while offering the advantage of assimilating various carbon sources such as glucose ethanol glycerol and acetic acid. The purpose of this work was to examine the ability of a C. cohnii strain to grow on different volatile fatty acids as well as on a pre-treated dark fermentation effluent and accumulate omega-3. The strain was found to grow well on relatively high concentrations of acetic butyric or propionic acid as main carbon source in a fed-batch pH-auxostat. Most importantly C. cohnii totally depleted the organic acid content of an ultra-filtrated dark fermentation effluent after 60 h of fed-batch cultivation therefore offering a bioprocess not only able to mitigate environmental pollutants but also to provide a solution for a sustainable energy production process. The accumulated docosahexaenoic acid content was as high as 29.8% (w/w) of total fatty acids.
Critical Morphological Phenomena During Ultra-lean Hydrogen-air Combustion in Closed Horizontal Hele-Shaw Cell
Sep 2021
Publication
Free quasi-two-dimensional outward propagation of the ultra-lean hydrogen-air flames was studied in a horizontal closed flat channel in order to minimize the influences of gravity and natural convection. Experiments were carried out with a sequential change of initial hydrogen concentration in the premixed gaseous hydrogen-air mixtures in the range from 3 to 12 vol. % H2 under normal pressure and temperature conditions. Two types of critical (in term of concentration threshold behavior) morphological phenomena were observed - formation of a pre-flame kernel and primary bifurcation of the pre-flame kernel and the higher order (secondary tertiary etc.) bifurcations of the individual locally spherical and restricted in space flame fronts. For the given initial ambient conditions (channel thickness initial gas mixture pressure and temperature) variation of initial mixture stoichiometry results in a few substantial changes in overall flame shape. These changes were recorded at the specific concentration limits which delineate three characteristic macroscopic morphological forms (morphotypes) of the ultra-lean hydrogen-air flame's ""trails"" - ""ray-like"" ""dendritic"" and ""quasi-uniform"". Transitions between the revealed basic flame morphotypes took place in different ways. The ""pre-flame kernel-to- rays"" and ""rays-to-dendrites"" transitions were abrupt and resembled the first order transitions in physics. -to-quasi-uniform morphology"" were significantly blurred and can be regarded as analogue to the second order transitions.
Current Research and Development Activities on Fission Products and Hydrogen Risk after the Accident at Fukushima Daiiichi Nuclear Power Station
Jan 2015
Publication
After the Fukushima Daiichi nuclear power plant (NPP) accident new regulatory requirements were enforced in July 2013 and a backfit was required for all existing nuclear power plants. It is required to take measures to prevent severe accidents and mitigate their radiological consequences. The Regulatory Standard and Research Department Secretariat of Nuclear Regulation Authority (S/NRA/R) has been conducting numerical studies and experimental studies on relevant severe accident phenomena and countermeasures. This article highlights fission product (FP) release and hydrogen risk as two major areas. Relevant activities in the S/NRA/R are briefly introduced as follows: 1. For FP release: Identifying the source terms and leak mechanisms is a key issue from the viewpoint of understanding the progression of accident phenomena and planning effective countermeasures that take into account vulnerabilities of containment under severe accident conditions. To resolve these issues the activities focus on wet well venting pool scrubbing iodine chemistry (in-vessel and ex-vessel) containment failure mode and treatment of radioactive liquid effluent. 2. For hydrogen risk: because of three incidents of hydrogen explosion in reactor buildings a comprehensive reinforcement of the hydrogen risk management has been a high priority topic. Therefore the activities in evaluation methods focus on hydrogen generation hydrogen distribution and hydrogen combustion.
Differentiating Gas Leaks from Normal Appliance Use
Jun 2021
Publication
DNV has carried out an investigation into potential uses for smart gas meter data as part of Phase 1 of the Modernising Energy Data Applications competition as funded by UK Research & Innovation. In particular a series of calculations have been carried out to investigate the possibility of differentiating accidental gas leaks from normal appliance use in domestic properties. This is primarily with the aim of preventing explosions but the detection of leaks also has environmental and financial benefits.
Three gases have been considered in this study:
An examination of detailed historical incident information suggests that the explosions that lead to fatalities or significant damage to houses are typically of the type that would be more likely to be detected and prevented. It is estimated that between 25% and 75% of the more severe explosions could be prevented depending on which potential improvements are implemented.
Based on the conservative estimates of explosion prevention a cost benefit analysis suggests that it is justifiable to spend between around £1 and £10 per meter installed to implement the proposed technology. This is based purely on lives saved and does not take account of other benefits.
Three gases have been considered in this study:
- A representative UK natural gas composition.
- A blend of 80% natural gas and 20% hydrogen.
- Pure hydrogen.
- Small holes of up to 1 mm rarely reach flammable gas/air concentrations for any gas except under the most unfavourable conditions such as small volumes combined with low ventilation rates. These releases would likely be detected within 6 to 12 hours.
- Medium holes between 1 mm and 6 mm give outflow rates equivalent to a moderate to high level of gas use by appliances. The ability to detect these leaks is highly dependent on the hole size the time at which the leak begins and the normal gas use profile in the building. The larger leaks in this category would be detected within 30 to 60 minutes while the smaller leaks could take several hours to be clearly differentiated from appliance use. This is quick enough to prevent some explosions.
- Large holes of over 6 mm give leak rates greater than any gas use by appliances. These releases rapidly reach a flammable gas/air mixture in most cases but would typically be detected within the first 30-minute meter output period. Again some explosions could be prevented in this timescale.
An examination of detailed historical incident information suggests that the explosions that lead to fatalities or significant damage to houses are typically of the type that would be more likely to be detected and prevented. It is estimated that between 25% and 75% of the more severe explosions could be prevented depending on which potential improvements are implemented.
Based on the conservative estimates of explosion prevention a cost benefit analysis suggests that it is justifiable to spend between around £1 and £10 per meter installed to implement the proposed technology. This is based purely on lives saved and does not take account of other benefits.
The Maritime Sector and Its Problematic Decarbonization: A Systematic Review of the Contribution of Alternative Fuels
May 2022
Publication
The present study seeks to select the most important articles and reviews from the Web of Science database that approached alternative fuels towards the decarbonization of the maritime sector. Through a systematic review methodology a combination of keywords and manual refining found a contribution of 103 works worldwide the European continent accounting for 57% of all publications. Twenty-two types of fuels were cited by the authors liquefied natural gas (LNG) hydrogen and biodiesel contributing to 49% of the mentions. Greenhouse gases sulfur oxide nitrogen oxide and particulate matter reductions are some of the main advantages of cleaner sources if used by the vessels. Nevertheless there is a lack of practical research on new standards engine performance cost and regulations from the academy to direct more stakeholders towards low carbon intensity in the shipping sector.
Safety Standard for Hydrogen and Hydrogen Systems Guidelines for Hydrogen System Design, Materials Selection, Operations, Storage and Transportation
Jan 1997
Publication
The NASA Safety Standard which establishes a uniform process for hydrogen system design materials selection operation storage and transportation is presented. The guidelines include suggestions for safely storing handling and using hydrogen in gaseous (GH2) liquid (LH2) or slush (SLH2) form whether used as a propellant or non-propellant. The handbook contains 9 chapters detailing properties and hazards facility design design of components materials compatibility detection and transportation. Chapter 10 serves as a reference and the appendices contained therein include: assessment examples; scaling laws explosions blast effects and fragmentation; codes standards and NASA directives; and relief devices along with a list of tables and figures abbreviations a glossary and an index for ease of use. The intent of the handbook is to provide enough information that it can be used alone but at the same time reference data sources that can provide much more detail if required.
Hydrogen Storage Behavior of TiFe Alloy Activated by Different Methods
Feb 2021
Publication
TiFe activation for hydrogen uptake was conducted through different methods and ball milling with ethanol proved to be the most effective one. TiFe alloy after activation could absorb 1.2 wt% hydrogen at room temperature with absorption and desorption plateaus of 0.5 MPa and 0.2 MPa respectively. Investigation on microstructure and chemical state of TiFe sample after milled with ethanol suggested that the well spread metallic Ti and Fe elements helped hydrogen uptake and release. The activation of TiFe alloy by milling with ethanol was achieved at ambient conditions with ease successfully and possibly can be used for large scale production
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.
Raw Biomass Electroreforming Coupled to Green Hydrogen Generation
Mar 2021
Publication
Despite the tremendous progress of coupling organic electrooxidation with hydrogen generation in a hybrid electrolysis electroreforming of raw biomass coupled to green hydrogen generation has not been reported yet due to the rigid polymeric structures of raw biomass. Herein we electrooxidize the most abundant natural amino biopolymer chitin to acetate with over 90% yield in hybrid electrolysis. The overall energy consumption of electrolysis can be reduced by 15% due to the thermodynamically and kinetically more favorable chitin oxidation over water oxidation. In obvious contrast to small organics as the anodic reactant the abundance of chitin endows the new oxidation reaction excellent scalability. A solar-driven electroreforming of chitin and chitin-containing shrimp shell waste is coupled to safe green hydrogen production thanks to the liquid anodic product and suppression of oxygen evolution. Our work thus demonstrates a scalable and safe process for resource upcycling and green hydrogen production for a sustainable energy future.
Emerging, Hydrogen-driven Electrochemical Water Purification
Jan 2022
Publication
Energy-efficient technologies for the remediation of water and generation of drinking water is a key towards sustainable technologies. Electrochemical desalination technologies are promising alternatives towards established methods such as reverse osmosis or ultrafiltration. In the last few years hydrogen-driven electrochemical water purification has emerged. This review article explores the concept of desalination fuel cells and capacitive-Faradaic fuel cells for ion separation.
A Review on the Properties of Iron Aluminide Intermetallics
Jan 2016
Publication
Iron aluminides have been among the most studied intermetallics since the 1930s when their excellent oxidation resistance was first noticed. Their low cost of production low density high strength-to-weight ratios good wear resistance ease of fabrication and resistance to high temperature oxidation and sulfurization make them very attractive as a substitute for routine stainless steel in industrial applications. Furthermore iron aluminides allow for the conservation of less accessible and expensive elements such as nickel and molybdenum. These advantages have led to the consideration of many applications such as brake disks for windmills and trucks filtration systems in refineries and fossil power plants transfer rolls for hot-rolled steel strips and ethylene crackers and air deflectors for burning high-sulfur coal. A wide application for iron aluminides in industry strictly depends on the fundamental understanding of the influence of (i) alloy composition; (ii) microstructure; and (iii) number (type) of defects on the thermo-mechanical properties. Additionally environmental degradation of the alloys consisting of hydrogen embrittlement anodic or cathodic dissolution localized corrosion and oxidation resistance in different environments should be well known. Recently some progress in the development of new micro- and nano-mechanical testing methods in addition to the fabrication techniques of micro- and nano-scaled samples has enabled scientists to resolve more clearly the effects of alloying elements environmental items and crystal structure on the deformation behavior of alloys. In this paper we will review the extensive work which has been done during the last decades to address each of the points mentioned above.
Methane Emissions from Natural Gas and LNG Imports: An Increasingly Urgent Issue for the Future of Gas in Europe
Nov 2020
Publication
Pressure is mounting on the natural gas and LNG community to reduce methane emissions and this is most urgent in EU countries following the adoption of much tougher greenhouse gas reduction targets of 2030 and the publication of the European Commission’s Methane Strategy. With rapidly declining indigenous EU production and therefore rising import dependence there are increasing calls for emissions from imported pipeline gas and LNG to be quantified and based on actual measurements as opposed to standard emission factors. The Methane Strategy promises to be a significant milestone in that process. Companies which are supplying (or intending to supply) natural gas to the EU – the largest global import market for pipeline gas and a very significant market for LNG – would be well advised to pay close attention to how the regulation of methane emissions is unfolding and to make an immediate and positive response. Failure to do so could accelerate the demise of natural gas in European energy balances faster than would otherwise have been the case and shorten the time available for transition to decarbonised gases – specifically hydrogen – using existing natural gas infrastructure.<br/>This EU initiative will (and arguably already has) attracted attention from non-EU governments and companies involved in global gas and LNG trade. We have already seen deliveries of `carbon neutral’ LNG cargos to Asia as well as a long-term LNG contract in which the greenhouse gas content of cargos will be measured reported and verified (MRV) according to an agreed methodology. Natural gas and LNG exports if based on these standards or those set out in the EU Methane Strategy may be able to command premium prices from buyers eager to demonstrate their own GHG reduction credentials to governments customers and civil society.
Heat to Hydrogen by RED—Reviewing Membranes and Salts for the RED Heat Engine Concept
Dec 2021
Publication
The Reverse electrodialysis heat engine (REDHE) combines a reverse electrodialysis stack for power generation with a thermal regeneration unit to restore the concentration difference of the salt solutions. Current approaches for converting low-temperature waste heat to electricity with REDHE have not yielded conversion efficiencies and profits that would allow for the industrialization of the technology. This review explores the concept of Heat-to-Hydrogen with REDHEs and maps crucial developments toward industrialization. We discuss current advances in membrane development that are vital for the breakthrough of the RED Heat Engine. In addition the choice of salt is a crucial factor that has not received enough attention in the field. Based on ion properties relevant for both the transport through IEMs and the feasibility for regeneration we pinpoint the most promising salts for use in REDHE which we find to be KNO3 LiNO3 LiBr and LiCl. To further validate these results and compare the system performance with different salts there is a demand for a comprehensive thermodynamic model of the REDHE that considers all its units. Guided by such a model experimental studies can be designed to utilize the most favorable process conditions (e.g. salt solutions).
Control of Electrons’ Spin Eliminates Hydrogen Peroxide Formation During Water Splitting
Jul 2017
Publication
The production of hydrogen through water splitting in a photoelectrochemical cell suffers from an overpotential that limits the efficiencies. In addition hydrogen-peroxide formation is identified as a competing process affecting the oxidative stability of photoelectrodes. We impose spin-selectivity by coating the anode with chiral organic semiconductors from helically aggregated dyes as sensitizers; Zn-porphyrins and triarylamines. Hydrogen peroxide formation is dramatically suppressed while the overall current through the cell correlating with the water splitting process is enhanced. Evidence for a strong spin-selection in the chiral semiconductors is presented by magnetic conducting (mc-)AFM measurements in which chiral and achiral Zn-porphyrins are compared. These findings contribute to our understanding of the underlying mechanism of spin selectivity in multiple electron-transfer reactions and pave the way toward better chiral dye-sensitized photoelectrochemical cells.
H2 Green Hydrogen Discussion Paper: Victorian Hydrogen Investment Program
Nov 2019
Publication
This discussion paper is for stakeholders who would like to shape the development of Victoria’s emerging green hydrogen sector identifying competitive advantages and priority focus areas for industry and the Victorian Government.<br/>The Victorian Government is using this paper to focus on the economic growth and sector development opportunities emerging for a Victorian hydrogen industry powered by renewable energy also known as ‘green’ hydrogen. In addition this paper seeks input from all stakeholders on how where and when the Victorian Government can act to establish a thriving green hydrogen economy.<br/>Although green hydrogen is the only type of hydrogen production within the scope of this discussion paper the development of the VHIP aligns with the policies projects and initiatives which support these other forms of hydrogen production. The VHIP is considering the broad policy landscape and actively coordinating with related hydrogen programs policies and strategies under development including the Council of Australian Governments (COAG) Energy Council’s National Hydrogen Strategy to ensure a complementary approach. In Victoria there are several programs and strategies in development and underway that have linkages with hydrogen and the VHIP.
Life Cycle Assessment of Fuel Cell Vehicles Considering the Detailed Vehicle Components: Comparison and Scenario Analysis in China Based on Different Hydrogen Production Schemes
Aug 2019
Publication
Numerous studies concerning the life cycle assessment of fuel cell vehicles (FCVs) have been conducted. However little attention has been paid to the life cycle assessment of an FCV from the perspective of the detailed vehicle components. This work conducts the life cycle assessment of Toyota Mirai with all major components considered in a Chinese context. Both the vehicle cycle and the fuel cycle are included. Both comprehensive resources and energy consumption and comprehensive environmental emissions of the life cycles are investigated. Potential environmental impacts are further explored based on CML 2001 method. Then different hydrogen production schemes are compared to obtain the most favorable solution. To explore the potential of the electrolysis the scenario analysis of the power structure is conducted. The results show that the most mineral resources are consumed in the raw material acquisition stage the most fossil energy is consumed in the use stage and global warming potential (GWP) value is fairly high in all life cycle stages of Toyota Mirai using electrolyzed hydrogen. For hydrogen production schemes the scenario analysis indicates that simply by optimizing the power structure the environmental impact of the electrolysis remains higher than other schemes. When using the electricity from hydropower or wind power the best choice will be the electrolysis.
Which way to Net Zero? A Comparative Analysis of Seven UK 2050 Decarbonisation Pathways
Dec 2021
Publication
Since the UK’s Net Zero greenhouse gas emissions target was set in 2019 organisations across the energy systems community have released pathways on how we might get there – which end-use technologies are deployed across each sector of demand how our fossil fuel-based energy supply would be transferred to low carbon vectors and to what extent society must change the way it demands energy services. This paper presents a comparative analysis between seven published Net Zero pathways for the UK energy system collected from Energy Systems Catapult National Grid ESO Centre for Alternative Technology and the Climate Change Committee. The key findings reported are that (i) pathways that rely on less stringent behavioural changes require more ambitious technology development (and vice versa); (ii) electricity generation will increase by 51-160% to facilitate large-scale fuel-switching in heating and transport the vast majority of which is likely to be generated from variable renewable sources; (iii) hydrogen is an important energy vector in meeting Net Zero for all pathways providing 100-591 TWh annually by 2050 though the growth in demand is heavily dependent on the extent to which it is used in supplying heating and transport demand. This paper also presents a re-visited analysis of the potential renewable electricity generation resource in the UK. It was found that the resource for renewable electricity generation outstrips the UK’s projected 2050 electricity demand by a factor 12-20 depending on the pathway. As made clear in all seven pathways large-scale deployment of flexibility and storage is required to match this abundant resource to our energy demand.
A Comprehensive Comparison of State-of-the-art Manufacturing Methods for Fuel Cell Bipolar Plates Including Anticipated Future Industry Trends
Nov 2020
Publication
This article explains and evaluates contemporary methods for manufacturing bipolar plates (BPPs) for lowtemperature polymer electrolyte membrane fuel cells (LT-PEMFC) and highlights the potential of new improved approaches. BPPs are an essential component of fuel cells responsible for distributing reaction gases to facilitate efficient conversion of gaseous electrochemical energy to electricity. BPPs must balance technical properties such as electrical and thermal conductivities structural strength and corrosion resistance. Graphitic and metallic materials can meet the required specifications with each material offering distinct advantages and disadvantages. Each materials’ performance is complimented by a comparison of its manufacturability including: the material costs production rates and required capital investment. These results are contextualised with respect to the target applications to identify the challenges and advantages of manufacturing methods of choice for BPPs. This analysis shows that the optimal choice of BPP manufacturing method depends entirely on the needs of the target application in particular the relative importance of manufacturing rate cost and the expected operational life of the bipolar plate to the fuel cell designer.
Enhanced Hydrogen Storage Properties of Mg by the Synergistic Effect of Grain Refinement and NiTiO 3 Nanoparticles
May 2021
Publication
As a promising hydrogen storage material the practical application of magnesium is obstructed by the stable thermodynamics and sluggish kinetics. In this paper three kinds of NiTiO3 catalysts with different mole ratio of Ni to Ti were successfully synthesized and doped into nanocrystalline Mg to improve its hydrogen storage properties. Experimental results indicated that all the Mg-NiTiO3 composites showed prominent hydrogen storage performance. Especially the Mg-NiTiO3/TiO2 composite could take up hydrogen at room temperature and the apparent activation energy for hydrogen absorption was dramatically decreased from 69.8 ± 1.2 (nanocrystalline Mg) kJ/mol to 34.2 ± 0.2 kJ/mol. In addition the hydrogenated sample began to release hydrogen at about 193.2 °C and eventually desorbed 6.6 wt% H2. The desorption enthalpy of the hydrogenated Mg-NiTiO3 -C was estimated to be 78.6 ± 0.8 kJ/mol 5.3 kJ/mol lower compared to 83.9 ± 0.7 kJ/mol of nanocrystalline Mg. Besides the sample revealed splendid cyclic stability during 20 cycles. No obvious recession occurred in the absorption and desorption kinetics and only 0.3 wt% hydrogen capacity degradation was observed. Further structural analysis demonstrates that nanosizing and catalyst doping led to a synergistic effect on the enhanced hydrogen storage performance of Mg-NiTiO3 -C composite which might serve as a reference for future design of highly effective hydrogen storage materials.
Hydrogen Fuel Cell Road Vehicles: State of the Art and Perspectives
Nov 2020
Publication
Driven by a small number of niche markets and several decades of application research fuel cell systems (FCS) are gradually reaching maturity to the point where many players are questioning the interest and intensity of its deployment in the transport sector in general. This article aims to shed light on this debate from the road transport perspective. It focuses on the description of the fuel cell vehicle (FCV) in order to understand its assets limitations and current paths of progress. These vehicles are basically hybrid systems combining a fuel cell and a lithium-ion battery and different architectures are emerging among manufacturers who adopt very different levels of hybridization. The main opportunity of Fuel Cell Vehicles is clearly their design versatility based on the decoupling of the choice of the number of Fuel Cell modules and hydrogen tanks. This enables manufacturers to meet various specifications using standard products. Upcoming developments will be in line with the crucial advantage of Fuel Cell Vehicles: intensive use in terms of driving range and load capacity. Over the next few decades long-distance heavy-duty vehicles and fleets of taxis or delivery vehicles will develop based on range extender or mild hybrid architectures and enable the hydrogen sector to mature the technology from niche markets to a large-scale market.
Powering a climate-neutral economy: An EU Strategy for Energy System Integration
Jul 2020
Publication
To become climate-neutral by 2050 Europe needs to transform its energy system which accounts for 75% of the EU's greenhouse gas emissions. The EU strategies for energy system integration and hydrogen adopted today will pave the way towards a more efficient and interconnected energy sector driven by the twin goals of a cleaner planet and a stronger economy.<br/><br/>The two strategies present a new clean energy investment agenda in line with the Commission's Next Generation EU recovery package and the European Green Deal. The planned investments have the potential to stimulate the economic recovery from the coronavirus crisis. They create European jobs and boost our leadership and competitiveness in strategic industries which are crucial to Europe's resilience.
Hydrogen Fuel Cell Aircraft for the Nordic Market
Mar 2024
Publication
A model for a fuel cell propelled 50 PAX hydrogen aircraft is developed. In terms of year 2045 Nordic air travel demand this aircraft is expected to cover 97% of travel distances and 58% of daily passenger volume. Using an ATR 42 as a baseline cryogenic tanks and fuel cell stacks are sized and propulsion system masses updated. Fuselage and wing resizing are required which increases mass and wetted area. Sizing methods for the multi-stack fuel cell and the cryogenic tanks are implemented. The dynamic aircraft model is updated with models for hydrogen consumption and tank pressure control. For the Multi-layer insulation (MLI) tank a trade study is performed. A ventilation pressure of 1.76 bar and 15 MLI layers are found to be optimal for the design mission. A return-without-refuel mission is explored where for a 10-hour ground hold 38.4% of the design range is retained out of the theoretically achievable 50%.
Hydrogen Production Possibility using Mongolian Renewable Energy
Jan 2019
Publication
There is widespread popular support for using renewable energy particularly solar and wind energy which provide electricity without giving rise to any carbon dioxide emissions. Harnessing these for electricity depends on the cost and efficiency of the technology which is constantly improving thus reducing costs per peak kilowatt and per kWh. Utilizing solar and wind-generated electricity in a stand-alone system requires corresponding battery or other storage capacity. The possibility of large-scale use of hydrogen in the future as a transport fuel increases the potential for both renewables and base-load electricity supply.
Critical Review of Models for H2-permeation Through Polymers with Focus on the Differential Pressure Method
May 2021
Publication
To reduce loss of hydrogen in storage vessels with high energy-to-weight-ratio new materials especially polymers have to be developed as barrier materials. Very established methods for characterization of barrier materials with permeation measurements are the time-lag and flow rate method along with the differential pressure method which resembles the nature of hydrogen vessel systems very well. Long measurement durations are necessary to gain suitable measurement data for these evaluation methods and often restrictive conditions have to be fulfilled. For these reasons common models for hydrogen permeation through single-layer and multi-layer membranes as well as models for hydrogen gas properties were collected and reviewed. Using current computer power together with these models can reduce measurement time for characterization of the barrier properties of materials while additional information about the quality of the measurement results is obtained.
Hydrogen Safety Prediction and Analysis of Hydrogen Refueling Station Leakage Accidents and Process Using Multi-Relevance Machine Learning
Oct 2021
Publication
Hydrogen energy vehicles are being increasingly widely used. To ensure the safety of hydrogenation stations research into the detection of hydrogen leaks is required. Offline analysis using data machine learning is achieved using Spark SQL and Spark MLlib technology. In this study to determine the safety status of a hydrogen refueling station we used multiple algorithm models to perform calculation and analysis: a multi-source data association prediction algorithm a random gradient descent algorithm a deep neural network optimization algorithm and other algorithm models. We successfully analyzed the data including the potential relationships internal relationships and operation laws between the data to detect the safety statuses of hydrogen refueling stations.
Green Hydrogen in the UK: Progress and Prospects
Apr 2022
Publication
Green hydrogen has been known in the UK since Robert Boyle described flammable air in 1671. This paper describes how green hydrogen has become a new priority for the UK in 2021 beginning to replace fossil hydrogen production exceeding 1 Mte in 2021 when the British Government started to inject significant funding into green hydrogen sources though much less than the USA Germany Japan and China. Recent progress in the UK was initiated in 2008 when the first UK green hydrogen station opened in Birmingham University refuelling 5 hydrogen fuel cell battery electric vehicles (HFCBEVs) for the 50 PhD chemical engineering students that arrived in 2009. Only 10 kg/day were required in contrast to the first large green ITM power station delivering almost 600 kg/day of green hydrogen that opened in the UK in Tyseley in July 2021. The first question asked in this paper is: ‘What do you mean Green?’. Then the Clean Air Zone (CAZ) in Birmingham is described with the key innovations defined. Progress in UK green hydrogen and fuel cell introduction is then recounted. The remarks of Elon Musk about this ‘Fool Cell; Mind bogglingly stupid’ technology are analysed to show that he is incorrect. The immediate deployment of green hydrogen stations around the UK has been planned. Another century may be needed to make green hydrogen dominant across the country yet we will be on the correct path once a profitable supply chain is established in 2022.
Bridging the Maritime-Hydrogen Cost-Gap: Real Options Analysis of Policy Alternatives
May 2022
Publication
Alternative and especially renewable marine fuels are needed to reduce the environmental and climate impacts of the shipping sector. This paper investigates the business case for hydrogen as an alternative fuel in a new-built vessel utilizing fuel cells and liquefied hydrogen. A real option approach is used to model the optimal time and costs for investment as well as the value of deferring an investment as a result of uncertainty. This model is then used to assess the impact of a carbon tax on a ship owner’s investment decision. A low carbon tax results in ship owners deferring investments which then slows the uptake of the technology. We recommend that policymakers set a high carbon tax at an early stage in order to help hydrogen compete with fossil fuels. A clear and timely policy design promotes further investments and accelerates the uptake of new technologies that can fulfill decarbonization targets.
Varying Load Distribution Impacts on the Operation of a Hydrogen Generator Plant
Oct 2021
Publication
This study advances several methods to evaluate the operation of a hydrogen generator plant. The model developed helps customize plants that contain multiple generators of varying powers using a decision module which determines the most efficient plant load distribution. Evaluation indices to assess individual devices within the plant are proposed and system flexibility maximizes the amount of renewable energy stored. Three case studies examined the variable load distribution of an electrolysis system connected to a 40 MW wind farm for energy storage purposes and incorporated a “night-valley” operational strategy. These methods facilitate the selection of the proper plant configuration and provide estimates for individual device effectiveness within the system.
Membrane-Based Electrolysis for Hydrogen Production: A Review
Oct 2021
Publication
Hydrogen is a zero-carbon footprint energy source with high energy density that could be the basis of future energy systems. Membrane-based water electrolysis is one means by which to produce high-purity and sustainable hydrogen. It is important that the scientific community focus on developing electrolytic hydrogen systems which match available energy sources. In this review various types of water splitting technologies and membrane selection for electrolyzers are discussed. We highlight the basic principles recent studies and achievements in membrane-based electrolysis for hydrogen production. Previously the NafionTM membrane was the gold standard for PEM electrolyzers but today cheaper and more effective membranes are favored. In this paper CuCl–HCl electrolysis and its operating parameters are summarized. Additionally a summary is presented of hydrogen production by water splitting including a discussion of the advantages disadvantages and efficiencies of the relevant technologies. Nonetheless the development of cost-effective and efficient hydrogen production technologies requires a significant amount of study especially in terms of optimizing the operation parameters affecting the hydrogen output. Therefore herein we address the challenges prospects and future trends in this field of research and make critical suggestions regarding the implementation of comprehensive membrane-based electrolytic systems.
Thermoacoustic Instability Considerations for High Hydrogen Combustion in Lean Premixed Gas Turbine Combustors: A Review
Jan 2021
Publication
Hydrogen is receiving increasing attention as a versatile energy vector to help accelerate the transition to a decarbonised energy future. Gas turbines will continue to play a critical role in providing grid stability and resilience in future low-carbon power systems; however it is recognised that this role is contingent upon achieving increased thermal efficiencies and the ability to operate on carbon-neutral fuels such as hydrogen. An important consideration in the development of gas turbine combustors capable of operating with pure hydrogen or hydrogen-enriched natural gas are the significant changes in thermoacoustic instability characteristics associated with burning these fuels. This article provides a review of the effects of burning hydrogen on combustion dynamics with focus on swirl-stabilised lean-premixed combustors. Experimental and numerical evidence suggests hydrogen can have either a stabilising or destabilising impact on the dynamic state of a combustor through its influence particularly on flame structure and flame position. Other operational considerations such as the effect of elevated pressure and piloting on combustion dynamics as well as recent developments in micromix burner technology for 100% hydrogen combustion have also been discussed. The insights provided in this review will aid the development of instability mitigation strategies for high hydrogen combustion.
Sizing Hydrogen Energy Storage in Consideration of Demand Response in Highly Renewable Generation Power Systems
May 2018
Publication
From an environment perspective the increased penetration of wind and solar generation in power systems is remarkable. However as the intermittent renewable generation briskly grows electrical grids are experiencing significant discrepancies between supply and demand as a result of limited system flexibility. This paper investigates the optimal sizing and control of the hydrogen energy storage system for increased utilization of renewable generation. Using a Finnish case study a mathematical model is presented to investigate the optimal storage capacity in a renewable power system. In addition the impact of demand response for domestic storage space heating in terms of the optimal sizing of energy storage is discussed. Finally sensitivity analyses are conducted to observe the impact of a small share of controllable baseload production as well as the oversizing of renewable generation in terms of required hydrogen storage size.
An Innovative Approach for Energy Transition in China? Chinese National Hydrogen Policies from 2001 to 2020
Jan 2023
Publication
To accelerate clean energy transition China has explored the potential of hydrogen as an energy carrier since 2001. Until 2020 49 national hydrogen policies were enacted. This paper explores the relevance of these policies to the development of the hydrogen industry and energy transition in China. We examine the reasons impacts and challenges of Chinese national hydrogen policies through the conceptual framework of Thomas Dye’s policy analysis method and the European Training Foundation’s policy analysis guide. This research provides an ex‐post analysis for previous policies and an ex‐ante analysis for future options. We argue that the energy supply revolution and energy technology revolution highlight the importance of hydrogen development in China. Particularly the pressure of the automobile industry transition leads to experimentation concerning the application of hydrogen in the transportation sector. This paper also reveals that hydro‐ gen policy development coincides with an increase in resource input and has positive spill over effects. Furthermore we note that two challenges have impeded progress: a lack of regulations for the industry threshold and holistic planning. To address these challenges the Chinese government can design a national hydrogen roadmap and work closely with other countries through the Belt and Road Initiative.
Hydrogen Recovery from Waste Gas Streams to Feed (High-Temperature PEM) Fuel Cells: Environmental Performance under a Life-Cycle Thinking Approach
Oct 2020
Publication
Fossil fuels are being progressively substituted by a cleaner and more environmentally friendly form of energy where hydrogen fuel cells stand out. However the implementation of a competitive hydrogen economy still presents several challenges related to economic costs required infrastructures and environmental performance. In this context the objective of this work is to determine the environmental performance of the recovery of hydrogen from industrial waste gas streams to feed high-temperature proton exchange membrane fuel cells for stationary applications. The life-cycle assessment (LCA) analyzed alternative scenarios with different process configurations considering as functional unit 1 kg of hydrogen produced 1 kWh of energy obtained and 1 kg of inlet flow. The results make the recovery of hydrogen from waste streams environmentally preferable over alternative processes like methane reforming or coal gasification. The production of the fuel cell device resulted in high contributions in the abiotic depletion potential and acidification potential mainly due to the presence of platinum metal in the anode and cathode. The design and operation conditions that defined a more favorable scenario are the availability of a pressurized waste gas stream the use of photovoltaic electricity and the implementation of an energy recovery system for the residual methane stream.
Hydrogen - A Sustainable Energy Carrier
Jan 2017
Publication
Hydrogen may play a key role in a future sustainable energy system as a carrier of renewable energy to replace hydrocarbons. This review describes the fundamental physical and chemical properties of hydrogen and basic theories of hydrogen sorption reactions followed by the emphasis on state-of-the-art of the hydrogen storage properties of selected interstitial metallic hydrides and magnesium hydride especially for stationary energy storage related utilizations. Finally new perspectives for utilization of metal hydrides in other applications will be reviewed.
Modeling of Fixed Bed Reactor for Coal Tar Hydrogenation via the Kinetic Lumping Approach
Nov 2018
Publication
Hydrogenation technology is an indispensable chemical upgrading process for converting the heavy feedstock into favorable lighter products. In this work a new kinetic model containing four hydrocarbon lumps (feedstock diesel gasoline cracking gas) was developed to describe the coal tar hydrogenation process the Levenberg–Marquardt’s optimization algorithm was used to determine the kinetic parameters by minimizing the sum of square errors between experimental and calculated data the predictions from model validation showed a good agreement with experimental values. Subsequently an adiabatic reactor model based on proposed lumped kinetic model was constructed to further investigate the performance of hydrogenation fixed-bed units the mass balance and energy balance within the phases in the reactor were taken into accounts in the form of ordinary differential equation. An application of the reactor model was performed for simulating the actual bench-scale plant of coal tar hydrogenation the simulated results on the products yields and temperatures distribution along with the reactor are shown to be good consistent with the experimental data.
Influence of Synthesis Gas Components on Hydrogen Storage Properties of Sodium Aluminium Hexahydride
Feb 2021
Publication
A systematic study of different ratios of CO CO2 N2 gas components on the hydrogen storage properties of the Na3AlH6 complex hydride with 4 mol% TiCl3 8 mol% aluminum and 8 mol% activated carbon is presented in this paper. The different concentrations of CO and CO2in H2 and CO CO2 N2 in H2 mixture were investigated. Both CO and CO2gas react with the complex hydride forming Al oxy-compounds NaOH and Na2CO3 that consequently cause serious decline in hydrogen storage capacity. These reactions lead to irreversible damage of complex hydride under the current experimental condition. Thus after 10 cycles with 0.1 vol % CO + 99.9 vol %H2 and 1 vol % CO + 99 vol %H2 the dehydrogenation storage capacity of the composite material decreased by 17.2% and 57.3% respectively. In the case of investigation of 10 cycles with 1 vol % CO2 + 99 vol % H2 gas mixture the capacity degradation was 53.5%. After 2 cycles with 10 vol % CO +90 vol % H2 full degradation was observed whereas after 6 cycles with 10 vol % CO2+ 90 vol % H2 degradation of 86.8% was measured. While testing with the gas mixture of 1.5 vol % CO + 10 vol % CO2+ 27 vol % H2 + 61.5 vol % N2 the degradation of 94% after 6 cycles was shown. According to these results it must be concluded that complex aluminum hydrides cannot be used for the absorption of hydrogen from syngas mixtures without thorough purification.
Electrical Double Layer Mechanism Analysis of PEM Water Electrolysis for Frequency Limitation of Pulsed Currents
Nov 2021
Publication
This paper proposes a method for improving hydrogen generation using pulse current in a proton exchange membrane-type electrolyzer (PEMEL). Traditional methods of electrolysis using direct current are known as the simplest approach to produce hydrogen. However it is highly dependent on environmental variables such as the temperature and catalyst used to enhance the rate of electrolysis. Therefore we propose electrolysis using a pulse current that can apply several dependent variables rather than environmental variables. The proposed method overcomes the difficulties in selecting the frequency of the pulse current by deriving factors affecting hydrogen generation while changing the concentration generated by the cell interface during the pulsed water-electrolysis process. The correlation between the electrolyzer load and the frequency characteristics was analyzed and the limit value of the applicable frequency of the pulse current was derived through electrical modeling. In addition the operating characteristics of PEMEL could be predicted and the PEMEL using the proposed pulse current was verified through experiments.
Hydrogen Embrittlement and Oxide Layer Effect in the Cathodically Charged Zircaloy-2
Apr 2020
Publication
Poland The present paper is aimed at determining the less investigated effects of hydrogen uptake on the microstructure and the mechanical behavior of the oxidized Zircaloy-2 alloy. The specimens were oxidized and charged with hydrogen. The different oxidation temperatures and cathodic current densities were applied. The scanning electron microscopy X-ray electron diffraction spectroscopy hydrogen absorption assessment tensile and nanoindentation tests were performed. At low oxidation temperatures an appearance of numerous hydrides and cracks and a slight change of mechanical properties were noticed. At high-temperature oxidation the oxide layer prevented the hydrogen deterioration of the alloy. For nonoxidized samples charged at different current density nanoindentation tests showed that both hardness and Young’s modulus revealed the minims at specific current value and the stepwise decrease in hardness during hydrogen desorption. The obtained results are explained by the barrier effect of the oxide layer against hydrogen uptake softening due to the interaction of hydrogen and dislocations nucleated by indentation test and hardening caused by the decomposition of hydrides. The last phenomena may appear together and result in hydrogen embrittlement in forms of simultaneous hydrogen-enhanced localized plasticity and delayed hydride cracking.
Assessment of Operational Degradation of Pipeline Steels
Jun 2021
Publication
This paper summarizes a series of the authors’ research in the field of assessing the operational degradation of oil and gas transit pipeline steels. Both mechanical and electrochemical properties of steels are deteriorated after operation as is their resistance to environmentally-assisted cracking. The characteristics of resistance to brittle fracture and stress corrosion cracking decrease most intensively which is associated with a development of in-bulk dissipated microdamages of the material. The most sensitive indicators of changes in the material’s state caused by degradation are impact toughness and fracture toughness by the J-integral method. The degradation degree of pipeline steels can also be evaluated nondestructively based on in-service changes in their polarization resistance and potential of the fracture surface. Attention is drawn to hydrogenation of a pipe wall from inside as a result of the electrochemical interaction of pipe metal with condensed moisture which facilitates operational degradation of steel due to the combined action of operating stresses and hydrogen. The development of microdamages along steel texture was evidenced metallographically as a trend to the selective etching of boundaries between adjacent bands of ferrite and pearlite and fractographically by revealing brittle fracture elements on the fracture surfaces namely delamination and cleavage indicating the sites of cohesion weakening between ferrite and pearlite bands. The state of the X52 steel in its initial state and after use for 30 years was assessed based on the numerical simulation method.
World Energy Issues Monitor 2020: Decoding New Signals of Change
Oct 2020
Publication
ISSUES MONITOR 2020: DECODING NEW SIGNALS OF CHANGE
The annual World Energy Issues Monitor provides unique insight into what energy policymakers CEOs and leading experts identify as Critical Uncertainties and Action Priorities. New this year the Issues Monitor also provides readers with the views of the individual customer detailing their perceptions of their role in the overall energy system. The Issues Monitor report includes a global issues map 58 country maps and six regional maps as well as perspectives from Future Energy Leaders (FEL) and energy innovators.
GLOBAL PERSPECTIVES
The 2020 global map incorporates all survey responses representing the views of over 3000 energy leaders from 104 countries. In this era of transition defined by decentralisation digitalisation and decarbonisation energy leaders must pay attention to many different signals of change and distinguish key issues from the noise. The Issues Monitor identifies shifting patterns of connected issues shaping energy transitions.
A NEW PULSE
The focus for the 2010s was about trying to automate and upgrade the energy system and set targets to move the energy transition forward. Digitalisation accelerated the transition of all sectors towards a more customer-centric environment. New policies and regulations were introduced to facilitate this transition and empower consumers. As a result the 2020s may very well be about realising those targets through a transition from activism to action.
TREND TRACKING: CCS
In comparing response from the Oil & Gas sector in 2015 with 2019 we found that almost half of respondents identified Carbon Capture & Storage (CCS) as a high impact issue in 2019 up from about a third in 2015. CCS is increasingly being viewed as an essential option for continued hydrocarbon use although governmental support is needed to enable scalability and cost effectiveness.
A DIFFERENCE IN OPINION: NUCLEAR
Opinions remain polarised but in many European countries nuclear power is increasingly recognised as a carbon-free energy source and potentially an integral part of the future energy mix. In December 2019 the European Commission set a target of net-zero carbon emissions by 2050. There is qualified support among energy leaders to include nuclear energy to help create a carbon neutral continent and enable a just energy transition.
The annual World Energy Issues Monitor provides unique insight into what energy policymakers CEOs and leading experts identify as Critical Uncertainties and Action Priorities. New this year the Issues Monitor also provides readers with the views of the individual customer detailing their perceptions of their role in the overall energy system. The Issues Monitor report includes a global issues map 58 country maps and six regional maps as well as perspectives from Future Energy Leaders (FEL) and energy innovators.
GLOBAL PERSPECTIVES
The 2020 global map incorporates all survey responses representing the views of over 3000 energy leaders from 104 countries. In this era of transition defined by decentralisation digitalisation and decarbonisation energy leaders must pay attention to many different signals of change and distinguish key issues from the noise. The Issues Monitor identifies shifting patterns of connected issues shaping energy transitions.
A NEW PULSE
The focus for the 2010s was about trying to automate and upgrade the energy system and set targets to move the energy transition forward. Digitalisation accelerated the transition of all sectors towards a more customer-centric environment. New policies and regulations were introduced to facilitate this transition and empower consumers. As a result the 2020s may very well be about realising those targets through a transition from activism to action.
TREND TRACKING: CCS
In comparing response from the Oil & Gas sector in 2015 with 2019 we found that almost half of respondents identified Carbon Capture & Storage (CCS) as a high impact issue in 2019 up from about a third in 2015. CCS is increasingly being viewed as an essential option for continued hydrocarbon use although governmental support is needed to enable scalability and cost effectiveness.
A DIFFERENCE IN OPINION: NUCLEAR
Opinions remain polarised but in many European countries nuclear power is increasingly recognised as a carbon-free energy source and potentially an integral part of the future energy mix. In December 2019 the European Commission set a target of net-zero carbon emissions by 2050. There is qualified support among energy leaders to include nuclear energy to help create a carbon neutral continent and enable a just energy transition.
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