United Kingdom
Performance and Failure Analysis of a Retrofitted Cessna Aircraft with a Fuel Cell Power System Fuelled with Liquid Hydrogen
Jan 2022
Publication
Proton-Exchange Membrane-Fuel Cells (PEM-FC) are regarded as one of the prime candidates to provide emissions-free electricity for propulsion systems of aircraft. Here a turbocharged Fuel Cell Power System (FCPS) powered with liquid H2 (LH2) is designed and modelled to provide a primary power source in retrofitted Cessna 208 Caravan aircraft. The proposed FCPS comprises multiple PEM-FCs assembled in stacks two single-stage turbochargers to mitigate the variation of the ambient pressure with altitude two preheaters two humidifiers and two combustors. Interlinked component sub-models are constructed in MATLAB and referenced to commercially available equipment. The FCPS model is used to simulate steady-state responses in a proposed 1.5 h (∼350 km) mission flight determining the overall efficiency of the FCPS at 43% and hydrogen consumption of ∼28 kg/h. The multi-stack FCPS is modelled applying parallel fluidic and electrical architectures analysing two power-sharing methods: equally distributed and daisy-chaining. The designed LH2-FCPS is then proposed as a power system to a retrofitted Cessna 208 Caravan and with this example analysed for the probability of failure occurrence. The results demonstrate that the proposed “dual redundant” FCPS can reach failure rates comparable to commercial jet engines with a rate below 1.6 failures per million hours.
Risk Perception of an Emergent Technology: The Case of Hydrogen Energy
Jan 2006
Publication
Although hydrogen has been used in industry for many years as a chemical commodity its use as a fuel or energy carrier is relatively new and expert knowledge about its associated risks is neither complete nor consensual. Public awareness of hydrogen energy and attitudes towards a future hydrogen economy are yet to be systematically investigated. This paper opens by discussing alternative conceptualisations of risk then focuses on issues surrounding the use of emerging technologies based on hydrogen energy. It summarises expert assessments of risks associated with hydrogen. It goes on to review debates about public perceptions of risk and in doing so makes comparisons with public perceptions of other emergent technologies—Carbon Capture and Storage (CCS) Genetically Modified Organisms and Food (GM) and Nanotechnology (NT)—for which there is considerable scientific uncertainty and relatively little public awareness. The paper finally examines arguments about public engagement and "upstream" consultation in the development of new technologies. It is argued that scientific and technological uncertainties are perceived in varying ways and different stakeholders and different publics focus on different aspects or types of risk. Attempting to move public consultation further "upstream" may not avoid this because the framing of risks and benefits is necessarily embedded in a cultural and ideological context and is subject to change as experience of the emergent technology unfolds.
Optimising Fuel Supply Chains within Planetary Boundaries: A Case Study of Hydrogen for Road Transport in the UK
Jul 2020
Publication
The world-wide sustainability implications of transport technologies remain unclear because their assessment often relies on metrics that are hard to interpret from a global perspective. To contribute to filling this gap here we apply the concept of planetary boundaries (PBs) i.e. a set of biophysical limits critical for operating the planet safely to address the optimal design of sustainable fuel supply chains (SCs) focusing on hydrogen for vehicle use. By incorporating PBs into a mixed-integer linear programming model (MILP) we identify SC configurations that satisfy a given transport demand while minimising the PBs transgression level i.e. while reducing the risk of surpassing the ecological capacity of the Earth. On applying this methodology to the UK we find that the current fossil-based sector is unsustainable as it transgresses the energy imbalance CO2 concentration and ocean acidification PBs heavily i.e. five to 55-fold depending on the downscale principle. The move to hydrogen would help to reduce current transgression levels substantially i.e. reductions of 9–86% depending on the case. However it would be insufficient to operate entirely within all the PBs concurrently. The minimum impact SCs would produce hydrogen via water electrolysis powered by wind and nuclear energy and store it in compressed form followed by distribution via rail which would require as much as 37 TWh of electricity per year. Our work unfolds new avenues for the incorporation of PBs in the assessment and optimisation of energy systems to arrive at sustainable solutions that are entirely consistent with the carrying capacity of the planet.
A Justice and Responsible Research and Innovation Exploration of Marine Renewables and Green Hydrogen in Island Communities
Oct 2022
Publication
Both marine renewables and hydrogen are being tested by the European Marine Energy Centre in the Orkney Islands Scotland. Given their emerging nature there is opportunity and risk pertaining to their development and deployment. This research will contribute conceptually and methodologically through the integration of energy justice and RRI conceptual frameworks strengthening justice analyses in relation to emerging energy technologies. This integrated model will be mobilized to critically scrutinize marine energy and green hydrogen as two future energy sources within the energy system. Following a technology-centered exploration of these technologies this work will then contextualise them into place-based considerations of Orkney’s just energy futures. Placing the technologies at the centre of the justice analysis insights will have the potential to inform their development and deployment in other locations. Exploring them within the local Orkney context will initiate an essential and important discussion of energy futures in this specific location. This presentation sets out the empirical and conceptual context for this work and presents a novel conceptual and methodological model combining energy justice and RRI frameworks. Moreover preliminary methods are discussed including methods and outcomes from co-creation workshops held at research design phase.
Batteries, Fuel Cells, or Engines? A Probabilistic Economic and Environmental Assessment of Electricity and Electrofuels for Heavy Goods Vehicles
Oct 2022
Publication
Uncertainty surrounding the total cost of ownership system costs and life cycle environmental impacts means that stakeholders may lack the required information to evaluate the risks of transitioning to low-carbon fuels and powertrains. This paper assesses the life cycle costs and well-to-wheel environmental impacts of using electricity and electrofuels in Heavy Good Vehicles (HGVs) whilst considering input parameter uncertainty. The complex relationship between electricity cost electrolyser capacity factor CO2 capture cost and electricity emissions intensity is assessed within a Monte Carlo based framework to identify scenarios where use of electricity or electrofuels in heavy goods vehicles makes economic and environmental sense. For vehicles with a range of less than 450 km battery electric vehicles achieve the lowest total cost of ownership for an electricity cost less than 100 €/MWh. For vehicles that require a range of up to 900 km hydrogen fuel cell vehicles represent the lowest long-term cost of abatement. Power-to-methane and power-to-liquid scenarios become economically competitive when low-cost electricity is available at high-capacity factors and CO2 capture costs for fuel synthesis are below 100 €/tCO2; these fuels may be more applicable to decarbonise shipping and aviation. Battery electric HGVs reduce greenhouse gas emissions by 50% compared to the diesel baseline with electricity emissions of 350 gCO2e/kWh. Electricity emissions less than 35 gCO2e/kWh are required for the power-to-methane and power-to-liquid scenarios to meet EU emissions savings criteria. High vehicle capital costs and a lack of widespread refuelling infrastructure may hinder initial uptake of low-carbon fuels and powertrains for HGVs.
A Review of the Role of Hydrogen in the Heat Decarbonization of Future Energy Systems: Insights and Perspectives
Apr 2024
Publication
Hydrogen is an emerging technology changing the context of heating with cleaner combustion than traditional fossil fuels. Studies indicate the potential to repurpose the existing natural gas infrastructure offering consumers a sustainable economically viable option in the future. The integration of hydrogen in combined heat and power systems could provide residential energy demand and reduce environmental emissions. However the widespread adoption of hydrogen will face several challenges such as carbon dioxide emissions from the current production methods and the need for infrastructure modification for transport and safety. Researchers indicated the viability of hydrogen in decarbonizing heat while some studies also challenged its long-term role in the future of heating. In this paper a comprehensive literature review is carried out by identifying the following key aspects which could impact the conclusion on the overall role of hydrogen in heat decarbonization: (i) a holistic view of the energy system considering factors such as renewable integration and system balancing; (ii) consumer-oriented approaches often overlook the broader benefits of hydrogen in emission reduction and grid stability; (iii) carbon capture and storage scalability is a key factor for large-scale production of low-emission blue hydrogen; (iv) technological improvements could increase the cost-effectiveness of hydrogen; (v) the role of hydrogen in enhancing resilience especially during extreme weather conditions raises the potential of hydrogen as a flexible asset in the energy infrastructure for future energy supply; and finally when considering the UK as a basis case (vi) incorporating factors such as the extensive gas network and unique climate conditions necessitates specific strategies.
Regional Supply Chains for Decarbonising Steel: Energy Efficiency and Green Premium Mitigation
Jan 2022
Publication
Decarbonised steel enabled by green hydrogen-based iron ore reduction and renewable electricity-based steel making will disrupt the traditional supply chain. Focusing on the energetic and techno-economic assessment of potential green supply chains this study investigates the direct reduced iron-electric arc furnace production route enabled by renewable energy and deployed in regional settings. The hypothesis that co-locating manufacturing processes with renewable energy resources would offer highest energy efficiency and cost reduction is tested through an Australia-Japan case study. The binational partnership is structured to meet Japanese steel demand (for domestic use and regional exports) and source both energy and iron ore from the Pilbara region of Western Australia. A total of 12 unique supply chains differentiated by spatial configuration timeline and energy carrier were simulated which validated the hypothesis: direct energy and ore exports to remote steel producers (i.e. Japan-based production) as opposed to co-locating iron and steel production with abundant ore and renewable energy resources (i.e. Australia-based production) increased energy consumption and the levelised cost of steel by 45% and 32% respectively when averaged across 2030 and 2050. Two decades of technological development and economies of scale realisation would be crucial; 2030 supply chains were on average 12% more energy-intense and 23% more expensive than 2050 equivalents. On energy vectors liquefied hydrogen was more efficient than ammonia for export-dominant supply chains due to the pairing of its process flexibility and the intermittent solar energy profile as well as the avoidance of the need for ammonia cracking prior to direct reduction. To mitigate the green premium a carbon tax in the range of A$66–192/t CO2 would be required in 2030 and A$0–70/t CO2 in 2050; the diminished carbon tax requirement in the latter is achievable only by wholly Australia-based production. Further the modelled system scale was immense; producing 40 Mtpa of decarbonised steel will require 74–129% of Australia’s current electricity output and A$137–328 billion in capital investment for solar power production and shipping vessel infrastructure. These results call for strategic planning of regional resource pairing to drive energy and cost efficiencies which accelerate the global decarbonisation of steel.
Enabling Hydrogen Blending From Industrial Clusters
Nov 2022
Publication
This study has been commissioned by the gas transporters as part of the Gas Goes Green (GGG)2 work programme to develop and report a ‘gas transporter view’ on how to facilitate hydrogen blending from industrial clusters which are likely to form the initial source for hydrogen blending in the gas network. This view has been developed through engagement carried out with industrial clusters and other stakeholders as well as drawing on learnings from a previous hydrogen blending study.3 The key takeaways of this study are that: l Enabling hydrogen blending from industrial clusters can be done in a pragmatic way with limited need for change to existing gas frameworks. l Where frameworks do need to change the changes are incremental rather than involving overhaul of existing frameworks and are highly workable. l While there remain uncertainties as to the nature of blending at each cluster (e.g. the volume and profile of hydrogen injections) in general the changes required to commercial and regulatory frameworks are the same implying that they are low regret. Below we summarise gas transporters’ preferred approach to facilitating hydrogen blending from industrial clusters including both the policy decisions needed and the changes required to commercial and regulatory frameworks. We note that this work has not involved a legal review and that one will be required as part of the process of implementing the framework changes described below.
Socio-technical Barriers to Domestic Hydrogen Futures: Repurposing Pipelines, Policies, and Public Perceptions
Feb 2023
Publication
The feasibility of the global energy transition may rest on the ability of nations to harness hydrogen's potential for cross-sectoral decarbonization. In countries historically reliant on natural gas for domestic heating and cooking such as the UK hydrogen may prove critical to meeting net-zero targets and strengthening energy security. In response the UK government is targeting industrial decarbonization via hydrogen with parallel interest in deploying hydrogen-fueled appliances for businesses and homes. However prospective hydrogen futures and especially the domestic hydrogen transition face multiple barriers which reflect the cross-sectoral dynamics of achieving economies of scale and social acceptance. Addressing these challenges calls for a deep understanding of socio-technical factors across different scales of the hydrogen economy. In response this paper develops a socio-technical systems framework for overcoming barriers to the domestic transition which is applied to the UK context. The paper demonstrates that future strategies should account for interactions between political techno-economic technical market and social dimensions of the hydrogen transition. In parallel to techno-economic feasibility the right policies will be needed to create an even playing field for green hydrogen technologies while also supporting stakeholder symbiosis and consumer buy-in. Future studies should grapple with how an effective repurposing of pipelines policies and public perceptions can be aligned to accelerate the development of the hydrogen economy with maximum net benefits for society and the environment.
Premier, Progress and Prospects in Renewable Hydrogen Generation: A Review
May 2023
Publication
Renewable hydrogen production has an opportunity to reduce carbon emissions in the transportation and industrial sectors. This method generates hydrogen utilizing renewable energy sources such as the sun wind and hydropower lowering the number of greenhouse gases released into the environment. In recent years considerable progress has been made in the production of sustainable hydrogen particularly in the disciplines of electrolysis biomass gasification and photoelectrochemical water splitting. This review article figures out the capacity efficiency and cost-effectiveness of hydrogen production from renewable sources effectively comparing the conventionally used technologies with the latest techniques which are getting better day by day with the implementation of the technological advancements. Governments investors and industry players are increasingly interested in manufacturing renewable hydrogen and the global need for clean energy is expanding. It is projected that facilities for manufacturing renewable hydrogen as well as infrastructure to support this development would expand hastening the transition to an environment-friendly and low-carbon economy
Enabling or Requiring Hydrogen-ready Industrial Boiler Equipment: Call for Evidence, Summary of Responses
Dec 2022
Publication
On 20 December 2021 the Department for Business Energy and Industrial Strategy (BEIS) launched a Call for Evidence (CfE) on enabling or requiring hydrogen-ready industrial boiler equipment. The aim was to gather evidence from a broad range of UK manufacturers industrial end-users supply chain participants and other experts to enable the development of proposals. The CfE was open for 12 weeks closing on 14 March 2022. The CfE followed the publication of the UK Hydrogen Strategy on 17 August 2021. In the Strategy government committed to run a CfE on hydrogen-ready industrial equipment by theend of 2022. The published CfE focussed on industrial boilers due to their widespread use and because BEIS analysis indicates a significant proportion of the demand for hydrogen in industry will come from this equipment category. Furthermore the technology required for hydrogen boilers is relatively advanced and more standardised than for other types of industrial<br/>equipment. For these reasons industrial boiler equipment presents a good test case for hydrogen-ready industrial equipment more broadly.<br/>The CfE contained the following three sections:<br/>• The opportunity for hydrogen-ready industrial boilers<br/>• The role for government to support hydrogen-ready industrial boiler equipment<br/>• The role of the supply chain and economic opportunities for the UK<br/>Respondents were asked to support their answers with evidence relating to their business product or sector published literature studies or to their broader expertise. To raise awareness of the CfE BEIS officials held two online webinars on 1 February 2022 and 3 February 2022. These were open to boiler manufacturers industrial end-users supply chain participants trade associations professional bodies and any other person(s) with an interest in the area.<br/>To build on evidence gathered through the CfE BEIS commissioned an independent study from Arup and Kiwa Gastec to further examine whether government should enable or require hydrogen-ready industrial boiler equipment. This study investigated the following topics:<br/>• definitions of hydrogen-readiness for industrial boilers<br/>• comparisons of the cost and resource requirement to install and convert hydrogen-ready industrial boiler equipment<br/>• industrial boiler supply chain capacity for conversion to hydrogen<br/>• estimates of the UK industrial boiler population<br/>The final report for this study has been published alongside the government response to the call for evidence. The conclusions and recommendations of that report do not necessarily represent the view of BEIS.
Hydrogen Strategy Update to the Market: July 2022
Jul 2022
Publication
Low carbon hydrogen is our new home-grown super-fuel which will be vital for our energy security and to meet our legally binding commitment to achieve net zero by 2050. The UK Hydrogen Strategy published in August 2021 outlined a comprehensive roadmap for the development of a thriving UK hydrogen economy over the coming decade. In the British Energy Security Strategy published in April this year the government doubled the UK’s hydrogen production ambition to up to 10GW by 2030. This increased ambition cements our place firmly at the forefront of the global race to develop hydrogen as a secure low carbon replacement for fossil fuels in the transition to greater energy security and net zero. Since the publication of the UK Hydrogen Strategy we have continued to deliver on our commitments setting out new policy and funding for hydrogen across the value chain and bringing together the international community around shared hydrogen objectives to rapidly develop a global hydrogen economy. Hydrogen was a key component of the Net Zero Strategy COP26 and the British Energy Security Strategy. The Hydrogen Investment Package and opening of the £240 million Net Zero Hydrogen Fund in April marked a major step forward in delivering government support to drive further private investment into hydrogen production in the UK. To keep industry informed on the government’s ongoing work to develop the hydrogen economy we committed in the UK Hydrogen Strategy to producing regular updates to the market as our policy develops. In addition to offering an accessible ‘one stop shop’ of government policy development and support schemes these updates will provide industry and investors with further clarity on the direction of travel of hydrogen policy across the value chain so that government and industry can work together most effectively and with the necessary pace to build a world-leading low carbon hydrogen sector in the UK.
A Multi-energy Multi-microgrid System Planning Model for Decarbonisation and Decontamination of Isolated Systems
May 2023
Publication
Decarbonising and decontaminating remote regions in the world presents several challenges. Many of these regions feature isolation dispersed demand in large areas and a lack of economic resources that impede the development of robust and sustainable networks. Furthermore isolated systems in the developing world are mostly based on diesel generation for electricity and firewood and liquefied petroleum gas for heating as these options do not require a significant infrastructure cost. In this context we present a stochastic multi-energy multi-microgrid system planning model that integrates electricity heat and hydrogen networks in isolated systems. The model is stochastic to capture uncertainty in renewable generation outputs particularly hydro and wind and thus design a multi-energy system proved secured against such uncertainty. The model also features two distinct constraints to limit the emissions of CO2 (for decarbonisation) and particulate matter (for decontamination) and incorporates firewood as a heating source. Moreover given that the focus is on low-voltage networks we introduce a fully linear AC power flow equations set allowing the planning model to remain tractable. The model is applied to a real-world case study to design a multi-energy multi-microgrid system in an isolated region in Chilean Patagonia. In a case with a zero limit over direct CO2 emissions the total system’s cost increases by 34% with respect to an unconstrained case. In a case with a zero limit over particulate matter emissions the total system’s cost increases by 189%. Finally although an absolute zero limit over both particulate matter and direct CO2 emissions leads to a total system’s cost increase of 650% important benefits in terms of decarbonisation and decontamination can be achieved at marginal cost increments.
Agreement for the Low Carbon Hydrogen Production Business Model
Dec 2022
Publication
The Heads of Terms for the Low Carbon Hydrogen Agreement sets out the government’s proposal for the final hydrogen production business model design. It will form the basis of the Low Carbon Hydrogen Agreement the business model contract between the government appointed counterparty and a low carbon hydrogen producer.<br/>The business model will provide revenue support to hydrogen producers to overcome the operating cost gap between low carbon hydrogen and high carbon fuels. It has been designed to incentivise investment in low carbon hydrogen production and use and in doing so deliver the government’s ambition of up to 10GW of low carbon hydrogen production capacity by 2030.
Technical and Economic Performance Assessment of Blue Hydrogen Production Using New Configuration Through Modelling and Simulation
Mar 2024
Publication
Steam methane reforming (SMR) is the dominant process for hydrogen production which produce large amount of carbon dioxide (CO2) as a by-product. To address concerns about carbon emissions there is an increasing focus on blue hydrogen to mitigate carbon emissions during hydrogen production. However the commercialization of blue hydrogen production (BHP) is hindered by the challenges of high cost and energy consumption. This study proposes a new configuration to address these challenges which is characterized by: (a) the use of piperazine (PZ) as a solvent which has a high CO2 absorption efficiency; (b) a more efficient heat exchange configuration which recovers the waste exergy from flue gas; (c) the advanced flash stripper (AFS) was adopted to reduce the capital cost due to its simpler stripper configuration. In addition the technical and economic performance of the proposed energy and cost-saving blue hydrogen production (ECSB) process is investigated and compared with the standard SMR process. The detailed models of the SMR process and the post-combustion carbon capture (PCC) process were developed and integrated in Aspen plus® V11. The results of the technical analysis showed that the ECSB process with 30 wt.% PZ achieves a 36.3 % reduction in energy penalty when compared to the standard process with 30 wt.% Monoethanolamine (MEA). The results of the economic analysis showed that the lowest levelized cost of blue hydrogen (LCBH) was achieved by the ECSB process with 30 wt.% PZ. Compared to the BHP process with 30 wt.% MEA the LCBH was reduced by 19.7 %.
Nuclear Cogeneration: Civil Nuclear Energy in a Low-carbon Future
Oct 2020
Publication
This policy briefing considers how the use of nuclear energy could be expanded to make the most of the energy produced and also to have the flexibility to complement an energy system with a growing input of intermittent renewable energy.<br/>What is nuclear cogeneration?<br/>Nuclear cogeneration is where the heat generated by a nuclear power station is used not only to generate electricity but to address some of the ‘difficult to decarbonise’ energy demands such as domestic heating and hydrogen production. It also enables a nuclear plant to be used more flexibly by switching between electricity generation and cogeneration applications.<br/>Applications for nuclear cogeneration<br/>Heat generated by civil nuclear reactors can be extracted at two different points for applications requiring either low-temperature or high-temperature heat. Each application differs in many aspects of operation and have different challenges.<br/>Low-temperature cogeneration<br/>Applications for the lower temperature ‘waste’ heat include:<br/>District heating<br/>Seawater desalination<br/>Low-temperature industrial process heating<br/>High-temperature cogeneration<br/>Higher temperature heat can be accessed earlier and used for:<br/>High-temperature industrial process heating<br/>Hydrogen production<br/>Sustainable synthetic fuel production<br/>Direct air capture<br/>Thermal energy storage<br/>Challenges of cogeneration systems<br/>Whilst some nuclear cogeneration applications have been employed in many countries the economic benefit of widescale nuclear cogeneration needs to be determined. However if the construction cost reductions for small modular reactors (SMRs) can be realised and the regulation and licencing processes streamlined then the additional revenue benefits of cogeneration could be material for SMRs and for the future of nuclear generation in the UK.<br/>Other outstanding issues include the ownership of reactors the future demand for hydrogen and other cogeneration products at a regional national and international level and the cost of carbon and dependable power.
Ammonia as Hydrogen Carrier for Transportation; Investigation of the Ammonia Exhaust Gas Fuel Reforming
Jun 2013
Publication
In this paper we show for the first time the feasibility of ammonia exhaust gas reforming as a strategy for hydrogen production used in transportation. The application of the reforming process and the impact of the product on diesel combustion and emissions were evaluated. The research was started with an initial study of ammonia autothermal reforming (NH3 e ATR) that combined selective oxidation of ammonia (into nitrogen and water) and ammonia thermal decomposition over a ruthenium catalyst using air as the oxygen source. The air was later replaced by real diesel engine exhaust gas to provide the oxygen needed for the exothermic reactions to raise the temperature and promote the NH3 decomposition. The main parameters varied in the reforming experiments are O2/NH3 ratios NH3 concentration in feed gas and gas e hourly e space e velocity (GHSV). The O2/NH3 ratio and NH3 concentration were the key factors that dominated both the hydrogen production and the reforming process efficiencies: by applying an O2/NH3 ratio ranged from 0.04 to 0.175 2.5e3.2 l/min of gaseous H2 production was achieved using a fixed NH3 feed flow of 3 l/min. The reforming reactor products at different concentrations (H2 and unconverted NH3) were then added into a diesel engine intake. The addition of considerably small amount of carbon e free reformate i.e. represented by 5% of primary diesel replacement reduced quite effectively the engine carbon emissions including CO2 CO and total hydrocarbons.
Gas Goes Green: Hydrogen Blending Capacity Maps
Jan 2022
Publication
Britain's gas networks are ready for hydrogen blending. Learn more about Britain's hydrogen blending capacity in the National Transmission System and Distribution Networks.
Hydrogen Strategy Update to the Market: December 2022
Dec 2022
Publication
The Government is committed to developing the UK’s low carbon hydrogen economy: hydrogen is considered critical to delivering energy security and our decarbonisation targets and presents a significant growth opportunity. It can play a pivotal role in our transition to a future based on renewable and nuclear energy while ensuring that natural gas used during this transition is from reliable sources including our own North Sea production and can provide clean energy for use in industry power transport and potentially home heating. In the UK Hydrogen Strategy we included the commitment to regularly summarise our policy development to keep industry apprised. Since publication of the Hydrogen Strategy we have doubled our low carbon hydrogen production capacity ambition to up to 10GW by 2030 (with at least half from electrolytic hydrogen) in the British Energy Security Strategy provided greater clarity to investors through the Hydrogen Investment Package and made substantial policy and funding strides across the hydrogen value chain. We summarised these ambitions commitments and actions in the first Hydrogen Strategy update to the market in July 2022. This was published alongside other key elements of our policy support which also included the launch of the first Electrolytic Hydrogen Allocation Round – offering joint Net Zero Hydrogen Fund (NZHF) and Hydrogen Production Business Model (HPBM) support – and our Hydrogen Sector Development Action Plan and the appointment of a UK Hydrogen Champion. Hydrogen is closely integrated into Government’s wider policy development on energy security and the energy transition both domestically and internationally with hydrogen policy previously announced through the Net Zero Strategy and the Breakthrough Agenda at COP26. This December 2022 Hydrogen Strategy update to the market summarises the extensive activity across Government since July to develop new hydrogen policy at pace and to design and deliver funding support. This includes announcements on shortlisted hydrogen projects in the Cluster Sequencing Process the launch of a consultation on hydrogen transport and storage (T&S) infrastructure the publication of the HPBM Heads of Terms and an update on the ongoing first Electrolytic Hydrogen Allocation Round. The hydrogen policy development presented here underlines the Government’s approach to promote every aspect of the UK hydrogen economy in collaboration with industry investors and international partners to create a strong globally competitive UK hydrogen sector.
A Review on Ports' Readiness to Facilitate International Hydrogen Trade
Jan 2023
Publication
The existing literature on the hydrogen supply chains has knowledge gaps. Most studies focus on hydrogen production storage transport and utilisation but neglect ports which are nexuses in the supply chains. To fill the gap this paper focuses on ports' readiness for the upcoming hydrogen international trade. Potential hydrogen exporting and importing ports are screened. Ports' readiness for hydrogen export and import are reviewed from perspectives of infrastructure risk management public acceptance regulations and standards and education and training. The main findings are: (1) liquid hydrogen ammonia methanol and LOHCs are suitable forms for hydrogen international trade; (2) twenty ports are identified that could be first movers; among them twelve are exporting ports and eight are importing ports; (3) ports’ readiness for hydrogen international trade is still in its infancy and the infrastructure construction or renovation risk management measures establishment of regulations and standards education and training all require further efforts.
Next for Net Zero Podcast: Transporting to a Greener World
Oct 2022
Publication
Decarbonisation will need a significant societal shift. The when why and how we travel is going to look very different within a decade. Joining us is Florentine Roy – a leading expert on electric vehicles and Innovation Project Lead at UK Power Networks and Matt Hindle - Head of Net Zero and Sustainability at Wales and West Utilities. Let’s talk about the energy system implications of this massive undertaking and how it can be enabled by innovation in a fair and just way.
The podcast can be found here.
The podcast can be found here.
The Key Techno-Economic and Manufacturing Drivers for Reducing the Cost of Power-to-Gas and a Hydrogen-Enabled Energy System
Jul 2021
Publication
Water electrolysis is a process which converts electricity into hydrogen and is seen as a key technology in enabling a net-zero compatible energy system. It will enable the scale-up of renewable electricity as a primary energy source for heating transport and industry. However displacing the role currently met by fossil fuels might require a price of hydrogen as low as 1 $/kg whereas renewable hydrogen produced using electrolysis is currently 10 $/kg. This article explores how mass manufacturing of proton exchange membrane (PEM) electrolysers can reduce the capital cost and thus make the production of renewable power to hydrogen gas (PtG) more economically viable. A bottom up direct manufacturing model was developed to determine how economies of scale can reduce the capital cost of electrolysis. The results demonstrated that (assuming an annual production rate of 5000 units of 200 kW PEM electrolysis systems) the capital cost of a PEM electrolysis system can reduce from 1990 $/kW to 590 $/kW based on current technology and then on to 431 $/kW and 300 $/kW based on the an installed capacity scale-up of ten- and one-hundred-fold respectively. A life-cycle costing analysis was then completed to determine the importance of the capital cost of an electrolysis system to the price of hydrogen. It was observed that based on current technology mass manufacturing has a large impact on the price of hydrogen reducing it from 6.40 $/kg (at 10 units units per year) to 4.16 $/kg (at 5000 units per year). Further analysis was undertaken to determine the cost at different installed capacities and found that the cost could reduce further to 2.63 $/kg and 1.37 $/kg based on technology scale-up by ten- and one hundred-fold respectively. Based on the 2030 (and beyond) baseline assumptions it is expected that hydrogen production from PEM electrolysis could be used as an industrial process feed stock provide power and heat to buildings and as a fuel for heavy good vehicles (HGVs). In the cases of retrofitted gas networks for residential or industrial heating solutions or for long distance transport it represents a more economically attractive and mass-scale compatible solution when compared to electrified heating or transport solutions.
Ammonia: Zero-carbon Fertiliser, Fuel and Energy Storage
Feb 2020
Publication
This briefing considers the opportunities and challenges associated with the manufacture and future use of zero-carbon ammonia which is referred to in this report as green ammonia. The production of green ammonia has the capability to impact the transition towards zero-carbon through the decarbonisation of its current major use in fertiliser production. Perhaps as significantly it has the following potential uses: • As a medium to store and transport chemical energy with the energy being released either by directly reacting with air or by the full or partial decomposition of ammonia to release hydrogen. • As a transport fuel by direct combustion in an engine or through chemical reaction with oxygen in the air in a fuel cell to produce electricity to power a motor. • To store thermal energy through the absorption of water and through phase changes between material states (for example liquid to gas).
Thermochemical Looping Technologies for Clean Hydrogen Production – Current Status and Recent Advances
Nov 2022
Publication
This review critically analyses various aspects of the most promising thermochemical cycles for clean hydrogen production. While the current hydrogen market heavily relies on fossil-fuel-based platforms the thermochemical water-splitting systems based on the reduction-oxidation (redox) looping reactions have a significant potential to significantly contribute to the sustainable production of green hydrogen at scale. However compared to the water electrolysis techniques the thermochemical cycles suffer from a low technology readiness level (TRL) which retards the commercial implementation of these technologies. This review mainly focuses on identifying the capability of the state-of-the-art thermochemical cycles to deploy large-scale hydrogen production plants and their techno-economic performance. This study also analyzed the potential integration of the hybrid looping systems with the solar and nuclear reactor designs which are evidenced to be more cost-effective than the electrochemical water-splitting methods but it excludes fossil-based thermochemical processes such as gasification steam methane reforming and pyrolysis. Further investigation is still required to address the technical issues associated with implementing the hybrid thermochemical cycles in order to bring them to the market for sustainable hydrogen production.
Blast Wave Generated by Delayed Ignition of Under-Expanded Hydrogen Free Jet at Ambient and Cryogenic Temperatures
Nov 2022
Publication
An under-expanded hydrogen jet from high-pressure equipment or storage tank is a potential incident scenario. Experiments demonstrated that the delayed ignition of a highly turbulent under-expanded hydrogen jet generates a blast wave able to harm people and damage property. There is a need for engineering tools to predict the pressure effects during such incidents to define hazard distances. The similitude analysis is applied to build a correlation using available experimental data. The dimensionless blast wave overpressure generated by delayed ignition and the follow-up deflagration or detonation of hydrogen jets at an any location from the jet ∆Pexp/P0 is correlated to the original dimensionless parameter composed of the product of the dimensionless ratio of storage pressure to atmospheric pressure Ps/P0 and the ratio of the jet release nozzle diameter to the distance from the centre of location of the fast-burning near-stoichiometric mixture on the jet axis (30% of hydrogen in the air by volume) to the location of a target (personnel or property) d/Rw. The correlation is built using the analysis of 78 experiments regarding this phenomenon in the wide range of hydrogen storage pressure of 0.5–65.0 MPa and release diameter of 0.5–52.5 mm. The correlation is applicable to hydrogen free jets at ambient and cryogenic temperatures. It is found that the generated blast wave decays inversely proportional to the square of the distance from the fast-burning portion of the jet. The correlation is used to calculate the hazard distances by harm thresholds for five typical hydrogen applications. It is observed that in the case of a vehicle with onboard storage tank at pressure 70 MPa the “no-harm” distance for humans reduces from 10.5 m to 2.6 m when a thermally activated pressure relief device (TPRD) diameter decreases from 2 mm to a diameter of 0.5 mm.
US-UK Scientific Forum on Sustainable Energy: Electrical Storage in Support of the Grid, Forum Report
Sep 2022
Publication
The effort to meet the ambitious targets of the Paris agreement is challenging many governments. The US and UK governments might have different approaches to achieving the targets but both will rely heavily on renewable energy sources such as wind and solar to power their economies. However these sources of power are unpredictable and ways will have to be developed to store renewable energy for hours days weeks seasons and maybe even years before it is used. As the disruptive and increasingly deadly impacts of climate change are being felt across the world the need to move to more sustainable sources of energy and to identify viable ways to store that energy has never been more important.<br/>This was the subject of the US–UK Science Forum on electrical storage in support of the grid which was held online from 17 – 18 March 2021. Co-organised by the Royal Society and the National Academy of Sciences it brought together a diverse group of 60 scientists policy makers industry leaders regulators and other key stakeholders for a wide-ranging discussion on all aspects of energy storage from the latest research in the field to the current status of deployment. It also considered the current national and international economic and policy contexts in which these developments are taking place. A number of key points emerged from the discussion. First it is clear that renewable energy will play an increasingly important role in the US and UK energy systems of the future and energy storage at a multi-terawatt hour scale has a vital role to play. Of course this will evolve differently to some extent in both countries and elsewhere according to the various geographical technological economic political social and regulatory environments. Second international collaboration is critical – no single nation will solve this problem alone. As two of the world’s leading scientific nations largest economies and per capita CO2 emitters with a long track record of collaboration the US and UK are well placed to play a vital role in addressing this critical challenge. As the discussion highlighted a wide range of energy storage technologies are now emerging and becoming increasingly available many of which have the potential to be critical components of a future net-zero energy system. A crucial next phase is in ensuring that these are technically developed as well as economically and political viable. This will require the support of a wide range of these potential solutions to ensure that their benefits remain widely available and to avoid costly ‘lock-in’. Scientists and science academies have a critical role to play in analysing technology options their combinations and their potential roles in future sustainable energy systems and in working with policymakers to incentivise investment and deployment.
Next for Net Zero Podcast: Unlock & Understand, Achieving a More Sustainable Future
Sep 2022
Publication
This episode examines how we are tackling a sustainable future – with Net Zero hurtling towards us at great pace. We’re around a year on from the pledges made at COP26 the UK’s Green Recovery initiative is well under way and by next year Britain is aiming to blend up to 20 per cent hydrogen into its gas networks. So now is the time to continue to unlock new insight and understand further the realities of both the challenges and opportunities ahead.
The podcast can be found here.
The podcast can be found here.
Techno Environmental Assessment of Flettner Rotor as Assistance Propulsion System for LH2 Tanker Ship Fuelled by Hydrogen
Nov 2022
Publication
This study presents a novel design and development of a 280000 m3 liquefied hydrogen tanker ship by implementing a set of 6 Flettner rotors as an assistance propulsion system in conjunction with a combined-cycle gas turbine fuelled by hydrogen as a prime mover. The study includes assessment of the technical and environmental aspects of the developed design. Furthermore an established method was applied to simulate the LH2 tanker in different voyages and conditions to investigate the benefits of harnessing wind energy to assist combined-cycle gas turbine in terms of performance and emission reduction based on engine behaviour for different voyages under loaded and unloaded normal as well as 6 % degraded engine and varying ambient conditions. The results indicate that implementing a set of 6 Flettner rotors for the LH2 tanker ship has the potential to positively impact the performance and lead to environmental benefits. A maximum contribution power of around 1.8 MW was achieved in the winter season owing to high wind speed and favourable wind direction. This power could save approximately 3.6 % of the combined-cycle gas turbine total output power (50 MW) and cause a 3.5 % reduction in NOx emissions.
Sustainable Synthetic Carbon Based Fuels for Transport
Sep 2019
Publication
The report considers two types of sustainable synthetic fuels: electro fuels (efuels) and synthetic biofuels. Efuels are made by combining hydrogen (from for example the electrolysis of water) with carbon dioxide (from direct air capture or a point source). Synthetic biofuels can be made from biological material (for example waste from forestry) or from further processing biofuels (for example ethanol).<br/>Whilst synthetic fuels can be “dropped in” to existing engines they are currently more expensive than fossil fuels and in the case of efuels could be thought of as an inefficient use of renewable electricity. However where renewable electricity is cheap and plentiful the manufacture and export of bulk efuels might make economic sense.<br/>Key research challenges identified include improving the fundamental understanding of catalysis; the need to produce cheap low-carbon hydrogen at scale; and developing sources of competitively priced low carbon energy are key to the development of synthetic efuels and biofuels. The UK has the research skills and capacity to improve many of these process steps such as in catalysis and biotechnology and to provide a further area of UK leadership in low-carbon energy.
Steady State Analysis of Gas Networks with Distributed Injection of Alternative Gas
Jun 2015
Publication
A steady state analysis method was developed for gas networks with distributed injection of alternative gas. A low pressure gas network was used to validate the method. Case studies were carried out with centralized and decentralized injection of hydrogen and upgraded biogas. Results show the impact of utilizing a diversity of gas supply sources on pressure distribution and gas quality in the network. It is shown that appropriate management of using a diversity of gas supply sources can support network management while reducing carbon emissions.
A System-Approach to Data can Help Install Trust and Enable a Net Zero Future
Mar 2021
Publication
Carbon capture and storage (CCS) and hydrogen will be a catalyst to deeply decarbonize the world’s energy system but not for another 15 years according to DNV’s Energy Transition Outlook. Many aspects from policy to technology developments can help to scale these technologies and accelerate the timeline.<br/>In the report A System-Approach to Data can Help Install Trust and Enable a Net Zero Future DNV considers what role data could play to support the initiation execution and operation of CCS and hydrogen projects.<br/>The research is based on interviews with representatives from across the UK energy supply chain. It focuses in particular on the emerging carbon and hydrogen industries and the cross sectoral challenges they face. It explores how data can facilitate the flow of the product both with respect to fiscal and technical risk matters.<br/>The report is intended for anyone involved in or has an interest in CCUS or hydrogen projects and in how data eco-systems will support the efficient operation and the transition to net-zero.<br/>DNV produced the report for and in partnership with the ODI an organization that advocates for the innovative use of open data to affect positive change across the globe.
Towards a Sustainable Hydrogen Economy: Optimisation-based Framework for Hydrogen Infrastructure Development
Sep 2016
Publication
This work studies the development of a sustainable hydrogen infrastructure that supports the transition towards a low-carbon transport system in the United Kingdom (UK). The future hydrogen demand is forecasted over time using a logistic diffusion model which reaches 50% of the market share by 2070. The problem is solved using an extension of SHIPMod an optimisation-based framework that consists of a multi-period spatially-explicit mixed-integer linear programming (MILP) formulation. The optimisation model combines the infrastructure elements required throughout the different phases of the transition namely economies of scale road and pipeline transportation modes and carbon capture and storage (CCS) technologies in order to minimise the present value of the total infrastructure cost using a discounted cash-flow analysis. The results show that the combination of all these elements in the mathematical formulation renders optimal solutions with the gradual infrastructure investments over time required for the transition towards a sustainable hydrogen economy.
Spatially Resolved Model for Studying Decarbonisation Pathways for Heat Supply and Infrastructure Trade-offs
Jun 2017
Publication
Heat decarbonisation is one of the main challenges of energy system decarbonisation. However existing energy planning models struggle to compare heat decarbonisation approaches because they rarely capture trade-offs between heat supply end-use technologies and network infrastructure at sufficient spatial resolution. A new optimisation model is presented that addresses this by including trade-offs between gas electricity and heat infrastructure together with related supply and end-use technologies with high spatial granularity. The model is applied in case studies for the UK. For the case modelled it is shown that electrification of heat is most cost-effective via district level heat pumps that supply heat networks instead of individual building heat pumps. This is because the cost of reinforcing the electricity grid for installing individual heat pumps does not sufficiently offset heat infrastructure costs. This demonstrates the importance of considering infrastructure trade-offs. When modelling the utilisation of a decarbonised gas the penetration of heat networks and location of district level heat supply technologies was shown to be dependent on linear heat density and on zone topology. This shows the importance of spatial aspects. Scenario-specific linear heat density thresholds for heat network penetration were identified. For the base case penetration of high temperature heat networks was over 50% and 60% by 2050 for linear heat densities over 1500 and 2500 kWh/m. For the case when medium heat temperature networks were additionally available a mix of both networks was observed. Medium temperature heat network penetration was over 20% 30% and 40% for linear heat densities of over 1500 2500 and 3000 kWh/m while high temperature heat network penetration was over 20% and 30% for linear heat densities of under 2000 and 1500 kWh/m respectively.
Neutron Scattering and Hydrogen Storage
Nov 2009
Publication
Hydrogen has been identified as a fuel of choice for providing clean energy for transport and other applications across the world and the development of materials to store hydrogen efficiently and safely is crucial to this endeavour. Hydrogen has the largest scattering interaction with neutrons of all the elements in the periodic table making neutron scattering ideal for studying hydrogen storage materials. Simultaneous characterisation of the structure and dynamics of these materials during hydrogen uptake is straightforward using neutron scattering techniques. These studies will help us to understand the fundamental properties of hydrogen storage in realistic conditions and hence design new hydrogen storage materials.
Possible Hydrogen Transitions in the UK: Critical Uncertainties and Possible Decision Points
Jun 2012
Publication
Many energy system optimization studies show that hydrogen may be an important part of an optimal decarbonisation mix but such analyses are unable to examine the uncertainties associated with breaking the ‘locked-in’ nature of incumbent systems. Uncertainties around technical learning rates; consumer behaviour; and the strategic interactions of governments automakers and fuel providers are particularly acute. System dynamics and agent-based models and studies of historical alternative fuel transitions have furthered our understanding of possible transition dynamics but these types of analysis exclude broader systemic issues concerning energy system evolution (e.g. supplies and prices of low-carbon energy) and the politics of transitions. This paper presents a hybrid approach to assessing hydrogen transitions in the UK by linking qualitative scenarios with quantitative energy systems modelling using the UK MARKAL model. Three possible transition pathways are explored each exploring different uncertainties and possible decision points with modelling used to inform and test key elements of each scenario. The scenarios draw on literature review and participatory input and the scenario structure is based on archetypal transition dynamics drawn from historical energy system transitions reflecting insights relating to innovation system development and resistance to change. Conclusions are drawn about appropriate policy responses.
Green Ammonia as a Spatial Energy Vector: A Review
May 2021
Publication
Green hydrogen is considered a highly promising vector for deep decarbonisation of energy systems and is forecast to represent 20% of global energy use by 2050. In order to secure access to this resource Japan Germany and South Korea have announced plans to import hydrogen; other major energy consumers are sure to follow. Ammonia a promising hydrogen derivative may enable this energy transport by densifying hydrogen at relatively low cost using well-understood technologies. This review seeks to describe a global green ammonia import/export market: it identifies benefits and limitations of ammonia relative to other hydrogen carriers the costs of ammonia production and transport and the constraints on both supply and demand. We find that green ammonia as an energy vector is likely to be critical to future energy systems but that gaps remain in the literature. In particular rigorous analysis of production and transport costs are rarely paired preventing realistic assessments of the delivered cost of energy or the selection of optimum import/export partners to minimise the delivered cost of ammonia. Filling these gaps in the literature is a prerequisite to the development of robust hydrogen and ammonia strategies and to enable the formation of global import and export markets of green fuel
Controlled Autoignition of Hydrogen in a Direct-injection Optical Engine
Mar 2021
Publication
Research into novel internal combustion engines requires consideration of the diversity in future fuels in an attempt to reduce drastically CO2 emissions from vehicles and promote energy sustainability. Hydrogen has been proposed as a possible fuel for future internal combustion engines and can be produced from renewable sources. Hydrogen’s wide flammability range allows higher engine efficiency than conventional fuels with both reduced toxic emissions and no CO2 gases. Most previous work on hydrogen engines has focused on spark-ignition operation. The current paper presents results from an optical study of controlled autoignition (or homogeneous charge compression ignition) of hydrogen in an engine of latest spark-ignition pentroof combustion chamber geometry with direct injection of hydrogen (100 bar). This was achieved by a combination of inlet air preheating in the range 200–400 C and residual gas recirculated internally by negative valve overlap. Hydrogen fuelling was set to various values of equivalence ratio typically in the range / = 0.40–0.63. Crank-angle resolved flame chemiluminescence images were acquired for a series of consecutive cycles at 1000 RPM in order to calculate in-cylinder rates of flame expansion and motion. Planar Laser Induced Fluorescence (LIF) of OH was also applied to record more detailed features of the autoignition pattern. Single and double (i.e. ‘split’ per cycle) hydrogen injection strategies were employed in order to identify the effect of mixture preparation on autoignition’s timing and spatial development. An attempt was also made to review relevant in-cylinder phenomena from the limited literature on hydrogen-fuelled spark-ignition optical engines and make comparisons were appropriate.
The Role of Renewable Hydrogen and Inter-seasonal Storage in Decarbonising Heat – Comprehensive Optimisation of Future Renewable Energy Value Chains
Nov 2018
Publication
Demands for space and water heating constitute a significant proportion of the total energy demands in Great Britain and are predominantly satisfied through natural gas which makes the heat sector a large emitter of carbon dioxide. Renewable hydrogen which can be injected into the gas grid or used directly in processes for generating heat and/or electricity is being considered as a low-carbon alternative energy carrier to natural gas because of its suitability for large-scale long- and short-term storage and low transportation losses all of which help to overcome the intermittency and seasonal variations in renewables. This requires new infrastructures for production storage transport and utilisation of renewable hydrogen – a hydrogen value chain – the design of which involves many interdependent decisions such as: where to locate wind turbines; where to locate electrolysers close to wind generation or close to demands; whether to transport energy as electricity or hydrogen and how; where to locate storage facilities; etc. This paper presents the Value Web Model a novel and comprehensive spatio-temporal mixed-integer linear programming model that can simultaneously optimise the design planning and operation of integrated energy value chains accounting for short-term dynamics inter-seasonal storage and investments out to 2050. It was coupled with GIS modelling to identify candidate sites for wind generation and used to optimise a number of scenarios for the production of hydrogen from onshore and offshore wind turbines in order to satisfy heat demands. The results show that over a wide range of scenarios the optimal pathway to heat is roughly 20% hydrogen and 80% electricity. Hydrogen storage both in underground caverns and pressurised tanks is a key enabling technology.
Effect of State of Charge on Type IV Hydrogen Storage Tank Rupture in a Fire
Sep 2021
Publication
The use of hydrogen storage tanks at 100% of nominal working pressure NWP is expected only after refuelling. Driving between refuellings is characterised by the state of charge SoC<100%. There is experimental evidence that Type IV tanks tested in a fire at initial pressures below one-third of its NWP depending on a fire source were leaking without rupture. This paper aims at understanding this phenomenon and the development of a predictive model. The numerical research has demonstrated that the heat transfer from fire through the composite overwrap is sufficient to melt the polymer liner. This initiates hydrogen microleaks through the composite wall before it loses the load-bearing ability when the resin degrades deep enough to cause the tank to rupture. The dependence of tank fire-resistance rating (FRR) on the SoC is presented for tanks of volume in the range 36-244 L. The tank wall thickness non-uniformity i.e. thinner composite at the dome area is identified as a serious issue for tank’s fire resistance that must be addressed by tank manufacturers and OEMs. The effect of the burst pressure ratio on FRR is investigated. It is concluded that thermal parameters of the composite wall i.e. decomposition heat and temperatures play a vital role in simulations of tank failure and thus FRR.
Hydrogen Informed Gurson Model for Hydrogen Embrittlement Simulation
Jul 2019
Publication
Hydrogen-microvoid interactions were studied via unit cell analyses with different hydrogen concentrations. The absolute failure strain decreases with hydrogen concentration but the failure loci were found to follow the same trend dependent only on stress triaxiality in other words the effects of geometric constraint and hydrogen on failure are decoupled. Guided by the decoupling principle a hydrogen informed Gurson model is proposed. This model is the first practical hydrogen embrittlement simulation tool based on the hydrogen enhanced localized plasticity (HELP) mechanism. It introduces only one additional hydrogen related parameter into the Gurson model and is able to capture hydrogen enhanced internal necking failure of microvoids with accuracy; its parameter calibration procedure is straightforward and cost efficient for engineering purpose
Fuel Cells for Shipping: To Meet On-board Auxiliary Demand and Reduce Emissions
Feb 2021
Publication
The reduction of harmful emissions from the international shipping sector is necessary. On-board energy demand can be categorised as either: propulsion or auxiliary services. Auxiliary services contribute a significant proportion of energy demand with major loads including: compressors pumps and HVAC (heating ventilation and air-conditioning). Typically this demand is met using the same fuel source as the main propulsion (i.e. fossil fuels). This study has analysed whether emissions from large scale ships could feasibly be reduced by meeting auxiliary demand by installing a hydrogen fuel cell using data from an LNG tanker to develop a case study. Simulations have shown that for a capacity of 10 x 40ft containers of compressed hydrogen the optimal fuel cell size would be 3 MW and this could save 10600 MWh of fossil fuel use equivalent to 2343 t of CO2. Hence this could potentially decarbonise a significant proportion of shipping energy demand. Although there are some notable technical and commercial considerations such as fuel cell lifetime and capital expenditure requirements. Results imply that if auxiliary loads could be managed to avoid peaks in demand this could further increase the effectiveness of this concept.
Our Green Print: Future Heat for Everyone
Jul 2021
Publication
Green Print - Future Heat for Everyone draws together technical consumer and economic considerations to create a pioneering plan to transition 22 million UK homes to low carbon heat by 2050.<br/>Our Green Print underlines the scale of the challenge ahead acknowledging that a mosaic of low carbon heating solutions will be required to meet the needs of individual communities and setting out 12 key steps that can be taken now in order to get us there<br/>The Climate Change Committee (CCC) estimates an investment spend of £250bn to upgrade insulation and heating in homes as well as provide the infrastructure to deliver the energy.<br/>This is a task of unprecedented scale the equivalent of retro-fitting 67000 homes every month from now until 2050. In this Report Cadent takes the industry lead in addressing the challenge.
Towards 2050 Net Zero Carbon Infrastructure: A Critical Review of Key Decarbonisation Challenges in the Domestic Heating Sector in the UK
Nov 2023
Publication
One of the most challenging sectors to meet “Net Zero emissions” target by 2050 in the UK is the domestic heating sector. This paper provides a comprehensive literature review of the main challenges of heating systems transition to low carbon technologies in which three distinct categories of challenges are discussed. The first challenge is of decarbonizing heat at the supply side considering specifically the difficulties in integrating hydrogen as a low-carbon heating substitute to the dominant natural gas. The next challenge is of decarbonizing heat at the demand side and research into the difficulties of retrofitting the existing UK housing stock of digitalizing heating energy systems as well as ensuring both retrofits and digitalization do not disproportionately affect vulnerable groups in society. The need for demonstrating innovative solutions to these challenges leads to the final focus which is the challenge of modeling and demonstrating future energy systems heating scenarios. This work concludes with recommendations for the energy research community and policy makers to tackle urgent challenges facing the decarbonization of the UK heating sector.
The Effect of Symmetrically Tilt Grain Boundary of Aluminum on Hydrogen Diffusion
Feb 2022
Publication
High-strength aluminum alloys are widely used in industry. Hydrogen embrittlement greatly reduces the performance and service safety of aluminum alloys. The hydrogen traps in aluminum profoundly affect the hydrogen embrittlement of aluminum. Here we took a coincidence-site lattice (CSL) symmetrically tilted grain boundary (STGB) Σ5(120)[001] as an example to carry out molecular dynamics (MD) simulations of hydrogen diffusion in aluminum at different temperatures and to obtain results and rules consistent with the experiment. At 700 K three groups of MD simulations with concentrations of 0.5 2.5 and 5 atomic % hydrogen (at. % H) were carried out for STGB models at different angles. By analyzing the simulation results and the MSD curves of hydrogen atoms we found that in the low hydrogen concentration of STGB models the grain boundaries captured hydrogen atoms and hindered their movement. In high-hydrogen-concentration models the diffusion rate of hydrogen atoms was not affected by the grain boundaries. The analysis of the simulation results showed that the diffusion of hydro-gen atoms at the grain boundary is anisotropic.
Impact of Hydrogen Liquefaction on Hydrogen Fuel Quality for Transport Applications (ISO-14687:2019)
Aug 2022
Publication
Decarbonisation of the energy sector is becoming increasingly more important to the reduction in climate change. Renewable energy is an effective means of reducing CO2 emissions but the fluctuation in demand and production of energy is a limiting factor. Liquid hydrogen allows for long-term storage of energy. Hydrogen quality is important for the safety and efficiency of the end user. Furthermore the quality of the hydrogen gas after liquefaction has not yet been reported. The purity of hydrogen after liquefaction was assessed against the specification of Hydrogen grade D in the ISO-14687:2019 by analysing samples taken at different locations throughout production. Sampling was carried out directly in gas cylinders and purity was assessed using multiple analytical methods. The results indicate that the hydrogen gas produced from liquefaction is of a higher purity than the starting gas with all impurities below the threshold values set in ISO-14687:2019. The amount fraction of water measured in the hydrogen sample increased with repeated sampling from the liquid hydrogen tank suggesting that the sampling system used was affected by low temperatures (−253 ◦C). These data demonstrate for the first time the impact of liquefaction on hydrogen purity assessed against ISO-14687:2019 showing that liquified hydrogen is a viable option for long-term energy storage whilst also improving quality.
Impact of Local Emergency Demand Response Programs on the Operation of Electricity and Gas Systems
Mar 2022
Publication
With increasing attention to climate change the penetration level of renewable energy sources (RES) in the electricity network is increasing. Due to the intermittency of RES gas‐fired power plants could play a significant role in backing up the RES in order to maintain the supply– demand balance. As a result the interaction between gas and power networks are significantly in‐ creasing. On the other hand due to the increase in peak demand (e.g. electrification of heat) net‐ work operators are willing to execute demand response programs (DRPs) to improve congestion management and reduce costs. In this context modeling and optimal implementation of DRPs in proportion to the demand is one of the main issues for gas and power network operators. In this paper an emergency demand response program (EDRP) is implemented locally to reduce the con‐ gestion of transmission lines and gas pipelines more efficiently. Additionally the effects of optimal implementation of local emergency demand response program (LEDRP) in gas and power networks using linear and non‐linear economic models (power exponential and logarithmic) for EDRP in terms of cost and line congestion and risk of unserved demand are investigated. The most reliable demand response model is the approach that has the least difference between the estimated demand and the actual demand. Furthermore the role of the LEDRP in the case of hydrogen injection instead of natural gas in the gas infrastructure is investigated. The optimal incentives for each bus or node are determined based on the power transfer distribution factor gas transfer distribution factor available electricity or gas transmission capability and combination of unit commitment with the LEDRP in the integrated operation of these networks. According to the results implementing the LEDRP in gas and power networks reduces the total operation cost up to 11% and could facilitate hydrogen injection to the network. The proposed hybrid model is implemented on a 24‐bus IEEE electricity network and a 15‐bus gas network to quantify the role and value of different LEDRP models.
Hydrogen Emissions from the Hydrogen Value Chain-emissions Profile and Impact to Global Warming
Feb 2022
Publication
Future energy systems could rely on hydrogen (H2) to achieve decarbonisation and net-zero goals. In a similar energy landscape to natural gas H2 emissions occur along the supply chain. It has been studied how current gas infrastructure can support H2 but there is little known about how H2 emissions affect global warming as an indirect greenhouse gas. In this work we have estimated for the first time the potential emission profiles (g CO2eq/MJ H2HHV) of H2 supply chains and found that the emission rates of H2 from H2 supply chains and methane from natural gas supply are comparable but the impact on global warming is much lower based on current estimates. This study also demonstrates the critical importance of establishing mobile H2 emission monitoring and reducing the uncertainty of short-lived H2 climate forcing so as to clearly address H2 emissions for net-zero strategies.
Towards a 100% Hydrogen Domestic Gas Network: Regulatory and Commercial Barriers to the First Demonstrator Project in the United Kingdom
May 2022
Publication
In the debate on the decarbonisation of heat renewable electricity tends to play a much more dominant role than green gases despite the potential advantages of gas in terms of utilising existing transportation networks and end-use appliances. Informed comparisons are hampered by information asymmetry; the renewable electricity has seen a huge grid level deployment whereas low-carbon hydrogen or bio-methane have been limited to some small stand-alone trials. This paper explores the regulatory and commercial challenges of implementing the first UK neighbourhood level 100% low-carbon hydrogen demonstration project. We draw on existing literature and action research to identify the key practical barriers currently hindering the ability of strategically important actors to accelerate the substitution of natural gas with low carbon hydrogen in local gas networks. This paper adds much needed contextual depth to existing generic and theoretical understandings of low-carbon hydrogen for heat transition feasibility. The learnings from pilot projects about the exclusion of hydrogen calorific value from the Local Distribution Zone calorific value calculation Special Purpose Vehicle companies holding of liability and future costs to consumers need to be quickly transferred into resilient operational practice or gas repurposing projects will continue to be less desirable than electrification using existing regulations and with more rapid delivery
A Zero Carbon Route to the Supply of High-temperature Heat Through the Integration of Solid Oxide Electrolysis Cells and H2–O2 Combustion
Aug 2022
Publication
Previously suggested options to achieve carbon neutrality involve the use of fossil fuels with carbon capture or exploiting biomass as sources of energy. Industrial high-temperature heating could possibly exploit electrical heating or combustion using hydrogen. However it is difficult to replace all the current coal or natural gas furnaces with these options for chemical industry. In this work a method that integrates solid oxide electrolysis cells (SOEC) and H2–O2 combustion is proposed and the related parameters are modelled to analyze their impacts. There is no waste heat and waste emissions in the proposed option and all substances are recycled. Unlike previous research the heat required for SOEC operation is generated from H2 combustion. The best working condition is under thermoneutral voltage and the highest electricity-to-thermal efficiency that can be achieved is 86.88% under a current density of 12000 A/m2 and operating temperature of 750 ◦C. Ohmic overpotential has the greatest effect on electricity consumption and the anode activation overpotential is the second most important option. Increasing combustion product temperature cannot significantly improve thermal efficiency but can raise the available maximum thermal energy.
Progress in Electrical Energy Storage System: A Critical Review
Jan 2009
Publication
Electrical energy storage technologies for stationary applications are reviewed. Particular attention is paid to pumped hydroelectric storage compressed air energy storage battery flow battery fuel cell solar fuel superconducting magnetic energy storage flywheel capacitor/supercapacitor and thermal energy storage. Comparison is made among these technologies in terms of technical characteristics applications and deployment status.
Numerical Simulations of Atmospheric Dispersion of Large-scale Liquid Hydrogen Releases
Sep 2021
Publication
Numerical simulations have been conducted for LH2 massive releases and the subsequent atmospheric dispersion using an in-house modified version of the open source computational fluid dynamics (CFD) code OpenFOAM. A conjugate heat transfer model has been added for heat transfer between the released LH2 and the ground. Appropriate interface boundary conditions are applied to ensure the continuities of temperature and heat fluxes. The significant temperature difference between the cryogenic hydrogen and the ground means that the released LH2 will instantly enter in a boiling state resulting in a hydrogen- air gaseous cloud which will initially behave like a dense gas. Numerical predictions have been conducted for the subsequent atmospheric dispersion of the vaporized LH2 for a series of release scenarios - with and without retention pits - to limit the horizontal spread of the LH2 on the ground. The considered cases included the instantaneous release of 1 10 and 50 tons of LH2 under neutral (D) and stable (F) weather conditions. More specifically 3F and 5D conditions were simulated with the former representing stable weather conditions under wind speed of 3 m/s at 10 m above the ground and the later corresponding to neutral weather conditions under 5 m/s wind speed (10 m above the ground). Specific numerical tests have also been conducted for selected scenarios under different ambient temperatures from 233 up to 313 K. According to the current study although the retention pit can extend the dispersion time it can significantly reduce the extent of hazards due to much smaller cloud size within both the flammability and explosion limits. While the former has negative impact on safety the later is beneficial. The use of retention pit should hence be considered with caution in practical applications.
Stand-off Detection of Hydrogen Concentration
Sep 2021
Publication
The ability to remotely monitor hydrogen and map its concentration is a pressing challenge in large scale production and distribution as well as other sectors such as nuclear storage. We present a photonicsbased approach for the stand-off sensing and mapping of hydrogen concentration capable of detecting and locating <0.1% concentrations at 100m distance. The technique identifies the wavelength of light resulting from interaction with laser pulses via Raman scattering and can identify a range of other gas species e.g. hydrocarbons ammonia by the spectroscopic analysis of the wavelengths present in the return signal. LIDAR Light Detection and Ranging – analogous to Radar is used for ranging. Laserbased techniques for the stand-off detection of hydrocarbons frequently employ absorption of light at specific wavelengths which are characteristic of the gas species. Unfortunately Hydrogen does not exhibit strong absorption however it does exhibit strong Raman scattering when excited in the UV wavelength range. Raman scattering is a comparatively weak effect. However the use of solid-state detectors capable of detecting single photons known as SPADS (Single Photon Avalanche Photodiode) enables the detection of low concentrations at range while making use of precise time-of-flight range location correlation. The initial safety case which necessitated our development of stand-off hydrogen sensing was the condition monitoring of stored nuclear waste supported and funded by Sellafield and the National Nuclear Laboratory in the UK. A deployable version of the device has been developed and hydrogen characterisation has been carried out in an active nuclear store. Prior to deployment a full ignition risk assessment was carried out. To the best of our knowledge this technique is the strongest candidate for the remote stand-off sensing of hydrogen.
HydroGenerally - Episode 1: The Colours of Hydrogen
Mar 2022
Publication
This first episode was inspired by an Innovate UK KTN perspective commenting on the UK government’s Hydrogen Strategy released by the Department of Business Energy and Industrial Strategy (BEIS) in August 2021. Following the publication of this perspective it was very evident to our Innovate UK KTN experts that the uses and challenges of ‘blue’ and ‘green’ hydrogens were generating a strong debate depending on their application areas.
Over a 20-minute discussion Simon Steffan and Sam try to answer the questions: how is hydrogen currently produced? How will it be produced in the future? And how will it fit in with the energy system?
The podcast can be found on their website
Over a 20-minute discussion Simon Steffan and Sam try to answer the questions: how is hydrogen currently produced? How will it be produced in the future? And how will it fit in with the energy system?
The podcast can be found on their website
Effect of Bipolar Plate Material on Proton Exchange Membrane Fuel Cell Performance
Mar 2022
Publication
Commercialization of proton exchange membrane fuel cells can only materials provided its performance is closely related to existing technologies useful in commercial application. Other critical parameters like the utilization of cheaper materials should be taken into account during the manufacturing of the cell. A key component in the cell that has direct correlation to the cell perfor‐ mance is the flow plate. The weight coupled with cost of the cell revolves around the flow plate used in the manufacturing of the cell. This study explores materials ideal for the manufacturing of fuel cells in order to improve the overall cell performance. The investigation highlights the critical impact of varying materials used in the manufacturing of flow plates for PEM fuel cells. Stainless steel (SS) aluminium (Al) and copper (Cu) were the materials considered. The flow plate designs considered were serpentine and open pore cellular foam channel. Machine learning using python for the validation of the results with Linear regression Ridge regression and Polynomial regression algorithm was carried out. The performance of both flow field channels was compared using dif‐ ferent bipolar plate materials. The results show that metal foam flow channels overall performance was better than serpentine flow channels with all the various bipolar plate material used and Al material outperformed Cu and SS material. There is a direct correlation in terms of the outcome of the study and literature based on the data generated experimentally. It can however be concluded that molecules of hydrogen are stable on aluminium plates compared to copper and stainless steel
The Role of Advanced Demand-sector Technologies and Energy Demand Reduction in Achieving Ambitious Carbon Budgets
Jan 2019
Publication
Limiting cumulative carbon emissions to keep global temperature increase to well below 2°C (and as low as 1.5°C) is an extremely challenging task requiring rapid reduction in the carbon intensity of all sectors of the economy and with limited leeway for residual emissions. Addressing residual emissions in ‘challenging-to-decarbonise’ sectors such as the industrial and aviation sectors relies on the development and commercialization of innovative advanced technologies currently still in their infancy. The aim of this study was to (a) explore the role of advanced technologies in achieving deep decarbonisation of the energy system and (b) provide technology- specific details of how rapid and deep carbon intensity reductions can be achieved in the energy demand sectors. This was done using TIAM-Grantham – a linear cost optimization model of the global energy system with a detailed representation of demand-side technologies. We find that the inclusion of advanced technologies in the demand sectors together with energy demand reduction through behavioural changes enables the model to achieve the rapid and deep decarbonisation of the energy system associated with limiting global warming to below 2°C whilst at the same time reduces reliance on negative emissions technologies by up to ∼18% compared to the same scenario with a standard set of technologies. Realising such advanced technologies at commercial scales as well as achieving such significant reductions in energy demand represents a major challenge for policy makers businesses and civil society. There is an urgent need for continued R&D efforts in the demand sectors to ensure that advanced technologies become commercially available when we need them and to avoid the gamble of overreliance on negative emissions technologies to offset residual emissions.
Electrification Versus Hydrogen for UK Road Freight: Conclusions from a Systems Analysis of Transport Energy Transitions
Mar 2022
Publication
Collectively the UK investment in transport decarbonisation is greater than £27B from government for incentivising zero-emission vehicles as part of an urgent response to decarbonise the transport sector. The investments made must facilitate a transition to a long-term solution. The success relies on coordinating and testing the evolution of both the energy and transport systems this avoids the risk of unforeseen consequences in both systems and therefore de-risks investment Here we present a semiquantitative energy and transport system analysis for UK road freight focusing on two primary investment areas for nation-wide decarbonisation namely electrification and hydrogen propulsion. Our study assembles and assesses the potential roadblocks of these energy systems into a concise record and considers the infrastructure in relation to all other components within the energy system. It highlights that for system-wide success and resilience a hydrogen system must overcome hydrogen production and distribution barriers whereas an electric system needs to optimise storage solutions and charging facilities. Without cohesive co-evolving energy networks the planning and operational modelling of transport decarbonisation may fall short of meaningful real-world results. A developed understanding of the dependencies between the energy and transport systems is a necessary step in the development of meaningful operational transport models that could de-risk investment in both the energy and transport systems.
Techno-Economic Evaluation of Deploying CCS in SMR Based Merchant H2 Production with NG as Feedstock and Fuel
Aug 2017
Publication
Hydrogen is a crucial raw materials to other industries. Globally nearly 90% of the hydrogen or HyCO gas produced is consumed by the ammonia methanol and oil refining industries. In the future hydrogen could play an important role in the decarbonisation of transport fuel (i.e. use of fuel cell vehicles) and space heating (i.e. industrial commercial building and residential heating). This paper summarizes the results of the feasibility study carried out by Amec Foster Wheeler for the IEA Greenhouse Gas R&D Programme (IEA GHG) with the purpose of evaluating the performance and costs of a modern steam methane reforming without and with CCS producing 100000 Nm3 /h H2 and operating as a merchant plant. This study focuses on the economic evaluation of five different alternatives to capture CO2 from SMR. This paper provides an up-to-date assessment of the performance and cost of producing hydrogen without and with CCS based on technologies that could be erected today. This study demonstrates that CO2 could be captured from an SMR plant with an overall capture rate ranging between 53 to 90%. The integration of CO2 capture plant could increase the NG consumption by -0.03 to 1.41 GJ per Nm3 /h of H2. The amount of electricity exported to the grid by the SMR plant is reduced. The levelised cost of H2 production could increase by 2.1 to 5.1 € cent per Nm3 H2 (depending on capture rate and technology selected). This translates to a CO2 avoidance cost of 47 to 70 €/t.
Study on Applicability of Energy-Saving Devices to Hydrogen Fuel Cell-Powered Ships
Mar 2022
Publication
The decarbonisation of waterborne transport is arguably the biggest challenge faced by the maritime industry presently. By 2050 the International Maritime Organization (IMO) aims to reduce greenhouse gas emissions from the shipping industry by 50% compared to 2008 with a vision to phase out fossil fuels by the end of the century as a matter of urgency. To meet such targets action must be taken immediately to address the barriers to adopt the various clean shipping options currently at different technological maturity levels. Green hydrogen as an alternative fuel presents an attractive solution to meet future targets from international bodies and is seen as a viable contributor within a future clean shipping vision. The cost of hydrogen fuel—in the shortterm at least—is higher compared to conventional fuel; therefore energy-saving devices (ESDs) for ships are more important than ever as implementation of rules and regulations restrict the use of fossil fuels while promoting zero-emission technology. However existing and emerging ESDs in standalone/combination for traditional fossil fuel driven vessels have not been researched to assess their compatibility for hydrogen-powered ships which present new challenges and considerations within their design and operation. Therefore this review aims to bridge that gap by firstly identifying the new challenges that a hydrogen-powered propulsion system brings forth and then reviewing the quantitative energy saving capability and qualitive additional benefits of individual existing and emerging ESDs in standalone and combination with recommendations for the most applicable ESD combinations with hydrogen-powered waterborne transport presented to maximise energy saving and minimise the negative impact on the propulsion system components. In summary the most compatible combination ESDs for hydrogen will depend largely on factors such as vessel types routes propulsion operation etc. However the mitigation of load fluctuations commonly encountered during a vessels operation was viewed to be a primary area of interest as it can have a negative impact on hydrogen propulsion system components such as the fuel cell; therefore the ESD combination that can maximise energy savings as well as minimise the fluctuating loads experienced would be viewed as the most compatible with hydrogen-powered waterborne transport.
Energy System Changes in 1.5 °C, Well Below 2 °C and 2 °C Scenarios
Dec 2018
Publication
Meeting the Paris Agreement's goal to limit global warming to well below 2 °C and pursuing efforts towards 1.5 °C is likely to require more rapid and fundamental energy system changes than the previously-agreed 2 °C target. Here we assess over 200 integrated assessment model scenarios which achieve 2 °C and well-below 2 °C targets drawn from the IPCC's fifth assessment report database combined with a set of 1.5 °C scenarios produced in recent years. We specifically assess differences in a range of near-term indicators describing CO2 emissions reductions pathways changes in primary energy and final energy across the economy's major sectors in addition to more detailed metrics around the use of carbon capture and storage (CCS) negative emissions low-carbon electricity and hydrogen.
Jet Zero Strategy: One Year On
Jul 2023
Publication
This report sets out progress against our strategic framework for decarbonising aviation as well as the latest aviation emissions data and updated Jet Zero analysis.<br/>Among the significant milestones achieved since the Jet Zero strategy launch are the:<br/>- agreement at the International Civil Aviation Organization for a long-term aspirational goal for aviation of net zero 2050 carbon dioxide (CO2) emissions for international aviation<br/>- publication of the 2040 zero emissions airport target call for evidence<br/>significant progress on sustainable aviation fuels (SAF) including:<br/>- publishing the second SAF mandate consultation<br/>- launching a second round of the Advanced Fuels Fund<br/>- publishing the Philip New report and the government response on how to develop a UK SAF industry<br/>- publication of the government response to the UK ETS consultation setting out a range of commitments that will enhance the effectiveness of the UK Emissions Trading Scheme (ETS) for aviation<br/>- launch of the expressions of interest for 2 DfT- funded research projects into aviation’s non-CO2 impacts<br/>The report also acknowledges that big challenges remain and we need to continue to work across the aviation sector and with experts across the economy to ensure we continue to make progress on our path to decarbonise aviation.
Quantifying the Impacts of Heat Decarbonisation Pathways on the Future Electricity and Gas Demand
May 2022
Publication
The decarbonisation of heat supply will play a critical role in meeting the emissions reduction target. There is however great uncertainty associated with the achievable levels of heat decarbonisation and the optimal heat technology mix which can have serious implications for the future electricity and gas demand. This work employs an integrated gas electricity and heat supply model to quantify the impacts of heat decarbonisation pathways on the future electricity and gas demand. A case study in the Great Britain is performed considering two heat decarbonisation scenarios in 2050: one is the predominantly electrified heat supply and the other is the predominantly hydrogen-based heat supply. The electricity demand becomes more volatile in the electrified heat scenario as the peak surges to 107.3 GW compared to 51.1 GW in the 2018 reference scenario while the peak in hydrogen-based heat scenario is 78.4 GW. The peak gas demand declines from 247.6 GW for 2018 to 81.7 GW for electrified heat scenario and to 85.1 GW for hydrogen-based heat scenario confirming that the seasonality associated with heat demand is shifting away from the gas network and towards electricity network. Moreover a sensitivity analysis shows that the future electricity demand is highly sensitive to parameters such as relative heat demand coefficient of performance of air source heat pumps and share of electricity in hydrogen production. Finally the application of a load shifting strategy demonstrates that demand-side flexibility has the potential to maintain the electricity system balance and minimise the generation and network infrastructure requirements arising from heat electrification. While the case study presented in this paper is based on the Great Britain the findings regarding the future electricity and gas demand are relevant for the global energy transition.
Thermocatalytic Hydrogen Production Through Decomposition of Methane-A Review
Oct 2021
Publication
Consumption of fossil fuels especially in transport and energy-dependent sectors has led to large greenhouse gas production. Hydrogen is an exciting energy source that can serve our energy purposes and decrease toxic waste production. Decomposition of methane yields hydrogen devoid of COx components thereby aiding as an eco-friendly approach towards large-scale hydrogen production. This review article is focused on hydrogen production through thermocatalytic methane decomposition (TMD) for hydrogen production. The thermodynamics of this approach has been highlighted. Various methods of hydrogen production from fossil fuels and renewable resources were discussed. Methods including steam methane reforming partial oxidation of methane auto thermal reforming direct biomass gasification thermal water splitting methane pyrolysis aqueous reforming and coal gasification have been reported in this article. A detailed overview of the different types of catalysts available the reasons behind their deactivation and their possible regeneration methods were discussed. Finally we presented the challenges and future perspectives for hydrogen production via TMD. This review concluded that among all catalysts nickel ruthenium and platinum-based catalysts show the highest activity and catalytic efficiency and gave carbon-free hydrogen products during the TMD process. However their rapid deactivation at high temperatures still needs the attention of the scientific community.
Jet Zero Strategy: Delivering Net Zero Aviation by 2050
Jul 2022
Publication
The Jet Zero strategy sets out how we will achieve net zero aviation by 2050.<br/>It focuses on the rapid development of technologies in a way that maintains the benefits of air travel whilst maximising the opportunities that decarbonisation can bring to the UK.<br/>The Jet Zero strategy includes a 5-year delivery plan setting out the actions that will need to be taken in the coming years to support the delivery of net zero aviation by 2050. We will be monitoring progress and reviewing and updating our strategy every 5 years.<br/>The strategy is informed by over 1500 responses to the Jet Zero consultation and the Jet Zero further technical consultation to which we have issued a summary of responses and government response.<br/>The Jet Zero investment flightpath is part of a series of roadmaps to be published over the course of 2022 for each sector of the Prime Minister’s Ten point plan for a green industrial revolution.<br/>It showcases the UK’s leading role in the development and commercialisation of new low and zero emission aviation technologies. It also highlights investment opportunities across systems efficiencies sustainable aviation fuels and zero emission aircraft.
Sustainable Ammonia Production Processes
Mar 2021
Publication
Due to the important role of ammonia as a fertilizer in the agricultural industry and its promising prospects as an energy carrier many studies have recently attempted to find the most environmentally benign energy efficient and economically viable production process for ammonia synthesis. The most commonly utilized ammonia production method is the Haber-Bosch process. The downside to this technology is the high greenhouse gas emissions surpassing 2.16 kgCO2-eq/kg NH3 and high amounts of energy usage of over 30 GJ/tonne NH3 mainly due to the strict operational conditions at high temperature and pressure. The most widely adopted technology for sustainable hydrogen production used for ammonia synthesis is water electrolysis coupled with renewable technologies such as wind and solar. In general a water electrolyzer requires a continuous supply of pretreated water with high purity levels for its operation. Moreover for production of 1 tonne of hydrogen 9 tonnes of water is required. Based on this data for the production of the same amount of ammonia through water electrolysis 233.6 million tonnes/yr of water is required. In this paper a critical review of different sustainable hydrogen production processes and emerging technologies for sustainable ammonia synthesis along with a comparative life cycle assessment of various ammonia production methods has been carried out. We find that through the review of each of the studied technologies either large amounts of GHG emissions are produced or high volumes of pretreated water is required or a combination of both these factors occur.
Water Electrolysis: From Textbook Knowledge to the Latest Scientific Strategies and Industrial Developments
May 2022
Publication
Replacing fossil fuels with energy sources and carriers that are sustainable environmentally benign and affordable is amongst the most pressing challenges for future socio-economic development. To that goal hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting if driven by green electricity would provide hydrogen with minimal CO2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness first principles calculations and machine learning. In addition a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the ‘junctions’ between the field’s physical chemists materials scientists and engineers as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains.
Life Cycle Assessment of Waste-to-hydrogen Systems for Fuel Cell Electric Buses in Glasgow, Scotland
Jun 2022
Publication
Waste-to-hydrogen (WtH) technologies are proposed as a dual-purpose method for simultaneous non-fossil-fuel based hydrogen production and sustainable waste management. This work applied the life cycle assessment approach to evaluate the carbon saving potential of two main WtH technologies (gasification and fermentation) in comparison to the conventional hydrogen production method of steam methane reforming (SMR) powering fuel cell electric buses in Glasgow. It was shown that WtH technologies could reduce CO2-eq emissions per kg H2 by 50–69% as compared to SMR. Gasification treating municipal solid waste and waste wood had global warming potentials of 4.99 and 4.11 kg CO2-eq/kg H2 respectively which were lower than dark fermentation treating wet waste at 6.6 kg CO2-eq/kg H2 and combined dark and photo fermentation at 6.4 kg CO2-eq/kg H2. The distance emissions of WtH-based fuel cell electric bus scenarios were 0.33–0.44 kg CO2-eq/km as compared to 0.89 kg CO2-eq/km for the SMR-based scenario.
Analysis of Control-System Strategy and Design of a Small Modular Reactor with Different Working Fluids for Electricity and Hydrogen Production as Part of a Decentralised Mini Grid
Mar 2022
Publication
Hydrogen is increasingly being viewed as a significant fuel for future industrial processes as it offers pathways to zero emission. The UK sees hydrogen as one of a handful of low-carbon solutions for transition to net zero. Currently most hydrogen production is from steam reforming of natural gas or coal gasification both of which involve the release of carbon dioxide. Hydrogen production from mini decentralised grids via a thermochemical process coupled with electricity production could offer favourable economics for small modular reactors (SMRs) whereby demand or grid management as a solution would include redirecting the power for hydrogen production when electricity demand is low. It also offers a clean-energy alternative to the aforementioned means. SMRs could offer favourable economics due to their flexible power system as part of the dual-output function. This study objective is to investigate the critical performance parameters associated with the nuclear power plant (NPP) the cycle working fluids and control-system design for switching between electricity and hydrogen demand to support delivery as part of a mini grid system for a reactor power delivering up to approximately 600 MWth power. The novelty of the work is in the holistic parametric analysis undertaken using a novel in-house tool which analyses the NPP using different working fluids with a control function bolt-on at the offtake for hydrogen production. The results indicate that the flow conditions at the offtake can be maintained. The choice of working fluids affects the pressure component. However the recuperator and heat-exchanger effectiveness are considered as efficiency-limiting factors for hydrogen production and electricity generation. As such the benefit of high-technology heat exchangers cannot be underestimated. This is also true when deciding on the thermochemical process to bolt onto the plant. The temperature of the gas at the end of the pipeline should also be considered to ensure that the minimum temperature-requirement status for hydrogen production is me
Global Trade of Hydrogen: What is the Best Way to Transfer Hydrogen Over Long Distances?
Aug 2022
Publication
As a manufactured fuel hydrogen can be produced in a decentralized way in most countries around the world. This means even in a net zero economy the global trade of hydrogen could look quite different to the current international trade in fossil fuels including natural gas. With further declines in the costs of renewable electricity and electrolyzers regions which have lower cost renewable electricity may develop an economic advantage in the production of low-cost hydrogen but for hydrogen to become a globally traded commodity the cost of imports needs to be lower than the cost of domestic production. Unlike oil or natural gas transporting hydrogen over long distances is not an easy task. Hydrogen liquefaction is an extremely energy-intensive process while maintaining the low temperature required for long-distance transportation and storage purposes results in additional energy losses and accompanying costs. The upside is that hydrogen can be converted into multiple carriers that have a higher energy density and higher transport capacity and can potentially be cheaper to transport over long distances. Among the substances currently identified as potential hydrogen carriers suitable for marine shipping liquid ammonia the so-called ‘liquid organic hydrogen carriers’ in general (toluene-methylcyclohexane (MCH) in particular) and methanol have received the most attention in recent years. This paper compares the key techno-economic characteristics of these potential carriers with that of liquified hydrogen in order to develop a better understanding of the ways in which hydrogen could be transported overseas in an efficient manner. The paper also discusses other factors beyond techno-economic features that may affect the choice of optimum hydrogen carrier for long distance transport as well as the global trade of hydrogen.
Heat in Buildings Strategy: Achieving Net Zero Emissions in Scotland's Buildings
Oct 2021
Publication
Sets out our vision for the future of heat in buildings and the actions we are taking in the buildings sector to deliver our climate change commitments maximise economic opportunities and ensure a just transition including helping address fuel poverty.
Towards Net-zero Compatible Hydrogen from Steam Reformation - Techno-economic Analysis of Process Design Options
Dec 2022
Publication
Increased consumption of low-carbon hydrogen is prominent in the decarbonisation strategies of many jurisdictions. Yet prior studies assessing the current most prevalent production method steam reformation of natural gas (SRNG) have not sufficiently evaluated how process design decisions affect life cycle greenhouse gas (GHG) emissions. This techno-economic case study assesses cradle-to-gate emissions of hydrogen produced from SRNG with CO2 capture and storage (CCS) in British Columbia Canada. Four process configurations with amine-based CCS using existing technology and novel process designs are evaluated. We find that cradle-to-gate GHG emission intensity ranges from 0.7 to 2.7 kgCO2e/kgH2 – significantly lower than previous studies of SRNG with CCS and similar to the range of published estimates for hydrogen produced from renewable-powered electrolysis. The levelized cost of hydrogen (LCOH) in this study (US$1.1–1.3/kgH2) is significantly lower than published estimates for renewable-powered electrolysis.
Strategies for the Sampling of Hydrogen at Refuelling Stations for Purity Assessment
Aug 2021
Publication
Hydrogen delivered at hydrogen refuelling station must be compliant with requirements stated in different standards which require specialized sampling device and personnel to operate it. Currently different strategies are implemented in different parts of the world and these strategies have already been used to perform 100s of hydrogen fuel sampling in USA EU and Japan. However these strategies have never been compared on a large systematic study. The purpose of this paper is to describe and compare the different strategies for sampling hydrogen at the nozzle and summarize the key aspects of all the existing hydrogen fuel sampling including discussion on material compatibility with the impurities that must be assessed. This review highlights the fact it is currently difficult to evaluate the impact or the difference these strategies would have on the hydrogen fuel quality assessment. Therefore comparative sampling studies are required to evaluate the equivalence between the different sampling strategies. This is the first step to support the standardization of hydrogen fuel sampling and to identify future research and development area for hydrogen fuel sampling.
Hydrogen Production, Distribution, Storage and Power Conversion in a Hydrogen Economy - A Technology Review
Aug 2021
Publication
To meet ambitious targets for greenhouse gas emissions reduction in the 2035-2050 timeframe hydrogen has been identified as a clean “green” fuel of interest. In comparison to fossil fuel use the burning of hydrogen results in zero CO2 emissions and it can be obtained from renewable energy sources. In addition to zero CO2 emissions hydrogen has several other attractive properties such as higher gravimetric energy content and wider flammability limits than most fossil fuels. However there are practical limitations to its widespread use at present which include low volumetric energy density in the gaseous state and high well-to-wheel costs when compared to fossil fuel production and distribution. In this paper a review is undertaken to identify the current state of development of key areas of the hydrogen network such as production distribution storage and power conversion technology. At present high technology costs still are a barrier to widespread hydrogen adoption but it is envisioned that as scale of production increases then costs are likely to fall. Technical barriers to a hydrogen economy adoption are not as significant as one might think as key technologies in the hydrogen network are already mature with working prototypes already developed for technologies such as liquid hydrogen composite cryotanks and proton exchange membrane fuel cells. It is envisioned that with continuous investment to achieve requisite scale that a hydrogen economy could be realised sooner rather than later with novel concepts such as turboelectric distributed propulsion enabled by a shift to hydrogen-powered network.
Solar Power and Energy Storage for Decarbonization of Land Transport in India
Dec 2021
Publication
By considering the weight penalty of batteries on payload and total vehicle weight this paper shows that almost all forms of land-based transport may be served by battery electric vehicles (BEV) with acceptable cost and driving range. Only long-distance road freight is unsuitable for battery electrification. The paper models the future Indian electricity grid supplied entirely by low-carbon forms of generation to quantify the additional solar PV power required to supply energy for transport. Hydrogen produced by water electrolysis for use as a fuel for road freight provides an inter-seasonal energy store that accommodates variations in renewable energy supply. The advantages and disadvantages are considered of midday electric vehicle charging vs. overnight charging considering the temporal variations in supply of renewable energy and demand for transport services. There appears to be little to choose between these two options in terms of total system costs. The result is an energy scenario for decarbonized surface transport in India based on renewable energy that is possible realistically achievable and affordable in a time frame of year 2050.
An Evaluation of Turbocharging and Supercharging Options for High-Efficiency Fuel Cell Electric Vehicles
Dec 2018
Publication
Mass-produced off-the-shelf automotive air compressors cannot be directly used for boosting a fuel cell vehicle (FCV) application in the same way that they are used in internal combustion engines since the requirements are different. These include a high pressure ratio a low mass flow rate a high efficiency requirement and a compact size. From the established fuel cell types the most promising for application in passenger cars or light commercial vehicle applications is the proton exchange membrane fuel cell (PEMFC) operating at around 80 ◦C. In this case an electric-assisted turbocharger (E-turbocharger) and electric supercharger (single or two-stage) are more suitable than screw and scroll compressors. In order to determine which type of these boosting options is the most suitable for FCV application and assess their individual merits a co-simulation of FCV powertrains between GT-SUITE and MATLAB/SIMULINK is realised to compare vehicle performance on the Worldwide Harmonised Light Vehicle Test Procedure (WLTP) driving cycle. The results showed that the vehicle equipped with an E-turbocharger had higher performance than the vehicle equipped with a two-stage compressor in the aspects of electric system efficiency (+1.6%) and driving range (+3.7%); however for the same maximal output power the vehicle’s stack was 12.5% heavier and larger. Then due to the existence of the turbine the E-turbocharger led to higher performance than the single-stage compressor for the same stack size. The solid oxide fuel cell is also promising for transportation application especially for a use as range extender. The results show that a 24-kWh electric vehicle can increase its driving range by 252% due to a 5 kW solid oxide fuel cell (SOFC) stack and a gas turbine recovery system. The WLTP driving range depends on the charge cycle but with a pure hydrogen tank of 6.2 kg the vehicle can reach more than 600 km.
The Evolution and Structure of Ignited High-pressure Cryogenic Hydrogen Jets
Jun 2022
Publication
The anticipated upscaling of hydrogen energy applications will involve the storage and transport of hydrogen at cryogenic conditions. Understanding the potential hazard arising from leaks in high-pressure cryogenic storage is needed to improve hydrogen safety. The manuscript reports a series of numerical simulations with detailed chemistry for the transient evolution of ignited high-pressure cryogenic hydrogen jets. The study aims to gain insight of the ignition processes flame structures and dynamics associated with the transient flame evolution. Numerical simulations were firstly conducted for an unignited jet released under the same cryogenic temperature of 80 K and pressure of 200 bar as the considered ignited jets. The predicted hydrogen concentrations were found to be in good agreement with the experimental measurements. The results informed the subsequent simulations of the ignited jets involving four different ignition locations. The predicted time series snapshots of temperature hydrogen mass fraction and the flame index are analyzed to study the transient evolution and structure of the flame. The results show that a diffusion combustion layer is developed along the outer boundary of the jet and a side diffusion flame is formed for the near-field ignition. For the far-field ignition an envelope flame is observed. The flame structure contains a diffusion flame on the outer edge and a premixed flame inside the jet. Due to the complex interactions between turbulence fuel-air mixing at cryogenic temperature and chemical reactions localized spontaneous ignition and transient flame extinguishment are observed. The predictions also captured the experimentally observed deflagration waves in the far-field ignited jets.
Overview of First Outcomes of PNR Project HYTUNNEL-CS
Sep 2021
Publication
Dmitry Makarov,
Donatella Cirrone,
Volodymyr V. Shentsov,
Sergii Kashkarov,
Vladimir V. Molkov,
Z. Xu,
Mike Kuznetsov,
Alexandros G. Venetsanos,
Stella G. Giannissi,
Ilias C. Tolias,
Knut Vaagsaether,
André Vagner Gaathaug,
Mark R. Pursell,
Wayne M. Rattigan,
Frank Markert,
Luisa Giuliani,
L.S. Sørensen,
A. Bernad,
Mercedes Sanz Millán,
U. Kummer,
Christian Brauner,
Paola Russo,
J. van den Berg,
F. de Jong,
Tom Van Esbroeck,
M. Van De Veire,
Didier Bouix,
Gilles Bernard-Michel,
Sergey Kudriakov,
Etienne Studer,
Domenico Ferrero,
Joachim Grüne and
G. Stern
The paper presents the first outcomes of the experimental numerical and theoretical studies performed in the funded by Fuel Cell and Hydrogen Joint Undertaking (FCH2 JU) project HyTunnel-CS. The project aims to conduct pre-normative research (PNR) to close relevant knowledge gaps and technological bottlenecks in the provision of safety of hydrogen vehicles in underground transportation systems. Pre normative research performed in the project will ultimately result in three main outputs: harmonised recommendations on response to hydrogen accidents recommendations for inherently safer use of hydrogen vehicles in underground traffic systems and recommendations for RCS. The overall concept behind this project is to use inter-disciplinary and inter-sectoral prenormative research by bringing together theoretical modelling and experimental studies to maximise the impact. The originality of the overall project concept is the consideration of hydrogen vehicle and underground traffic structure as a single system with integrated safety approach. The project strives to develop and offer safety strategies reducing or completely excluding hydrogen-specific risks to drivers passengers public and first responders in case of hydrogen vehicle accidents within the currently available infrastructure.
Recent Progress in Ammonia Fuel Cells and their Potential Applications
Nov 2020
Publication
Conventional technologies are largely powered by fossil fuel exploitation and have ultimately led to extensive environmental concerns. Hydrogen is an excellent carbon-free energy carrier but its storage and long-distance transportation remain big challenges. Ammonia however is a promising indirect hydrogen storage medium that has well-established storage and transportation links to make it an accessible fuel source. Moreover the notion of ‘green ammonia’ synthesised from renewable energy sources is an emerging topic that may open significant markets and provide a pathway to decarbonise a variety of applications reliant on fossil fuels. Herein a comparative study based on the chosen design working principles advantages and disadvantages of direct ammonia fuel cells is summarised. This work aims to review the most recent advances in ammonia fuel cells and demonstrates how close this technology type is to integration with future applications. At present several challenges such as material selection NOx formation CO2 tolerance limited power densities and long-term stability must still be overcome and are also addressed within the contents of this review
The Hydrogen Fuel Cell Battery: Replacing the Combustion Engine in Heavy Vehicles
Nov 2022
Publication
This opinion piece describes how the optimal integration of hydrogen-fuel-cell with battery in a heavy highly-utilised vehicle can extend vehicle range while cutting refuelling time and reducing cost compared to a pure battery electric vehicle.
Life Cycle Analysis of Hydrogen Powered Marine Vessels—Case Ship Comparison Study with Conventional Power System
Aug 2023
Publication
The latest International Maritime Organization strategies aim to reduce 70% of the CO2 emissions and 50% of the Greenhouse Gas (GHG) emissions from maritime activities by 2050 compared to 2008 levels. The EU has set up goals to reduce GHG emissions by at least 55% by 2030 compared to 1990 and achieve net-zero GHG emissions by 2050. The UK aims to achieve more than 68% GHG emission reduction by 2030 and net-zero GHG emissions by 2050. There are many solutions under development to tackle the challenge of meeting the latest decarbonization strategies from the IMO EU and UK among which are hydrogen powered marine vessels. This paper presents a life cycle analysis study for hydrogen fuelled vessels by evaluating their performance in terms of environmental friendliness and economic feasibility. The LCA study will consider the gas emissions and costs during the life stages of the ships including the construction operation maintenance and recycling phases of the selected vessels. The results of the comparisons with the conventional version of the ships (driven by diesel generators) demonstrate the benefits of using hydrogen for marine transportation: over 80% emission reduction and around 60% life cycle cost savings. A sensitivity analysis shows that the prices of fuels and carbon credits can affect the life cycle cost and recommendations for low H2 price and high carbon credit in the future are provided to attract the industry to adopt the new fuel.
A Systems-Level Study of Ammonia and Hydrogen for Maritime Transport
Aug 2023
Publication
An energy systems comparison of grid-electricity derived liquid hydrogen (LH2) and liquid ammonia (LNH3) is conducted to assess their relative potential in a low-carbon future. Under various voyage weather conditions their performance is analysed for use in cargo transport energy vectors for low-carbon electricity transport and fuel supply. The analysis relies on literature projections for technological development and grid decarbonisation towards 2050. Various voyages are investigated from regions such as North America (NA) Europe (E) and Latin America (LA) to regions projected to have a higher electricity and fuel grid carbon intensity (CI) (i.e. Asia Pacific Africa the Middle-East and the CIS). In terms of reducing the CI of electricity and fuel at the destination port use of LH2 is predicted to be favourable relative to LNH3 whereas LNH3 is favourable for low-carbon transport of cargo. As targeted by the International Maritime Organisation journeys of LNH3 cargo ships originating in NA E and LA achieve a reduction in volumetric energy efficiency design index (kg-CO2/m3 -km) of at least 70% relative to 2008 levels. The same targets can be met globally if LH2 is supplied to high CI regions for production of LNH3 for cargo transport. A future shipping system thus benefits from the use of both LH2 and LNH3 for different functions. However there are additional challenges associated with the use of LH2. Relative to LNH3 1.6 to 1.7 times the number of LH2 ships are required to deliver the same energy. Even when reliquefaction is employed their success is reliant on the avoidance of rough sea states (i.e. Beaufort Numbers >= 6) where fuel depletion rates during a voyage are impractical.
Optimal Design and Analysis of a Hybrid Hydrogen Energy Storage System for an Island-Based Renewable Energy Community
Oct 2023
Publication
Installations of decentralised renewable energy systems (RES) are becoming increasing popular as governments introduce ambitious energy policies to curb emissions and slow surging energy costs. This work presents a novel model for optimal sizing for a decentralised renewable generation and hybrid storage system to create a renewable energy community (REC) developed in Python. The model implements photovoltaic (PV) solar and wind turbines combined with a hybrid battery and regenerative hydrogen fuel cell (RHFC). The electrical service demand was derived using real usage data from a rural island case study location. Cost remuneration was managed with an REC virtual trading layer ensuring fair distribution among actors in accordance with the European RED(III) policy. A multi-objective genetic algorithm (GA) stochastically determines the system capacities such that the inherent trade-off relationship between project cost and decarbonisation can be observed. The optimal design resulted in a levelized cost of electricity (LCOE) of 0.15 EUR/kWh reducing costs by over 50% compared with typical EU grid power with a project internal rate of return (IRR) of 10.8% simple return of 9.6%/year and return on investment (ROI) of 9 years. The emissions output from grid-only use was reduced by 72% to 69 gCO2 e/kWh. Further research of lifetime economics and additional revenue streams in combination with this work could provide a useful tool for users to quickly design and prototype future decentralised REC systems.
A Holistic Framework for the Optimal Design and Operation of Electricity, Heating, Cooling and Hydrogen Technologies in Buildings
Jun 2024
Publication
In this work the Design and Operation of Integrated Technologies (DO-IT) framework is developed a comprehensive tool to support short- and long-term technology investment and operation decisions for integrated energy generation conversion and storage technologies in buildings. The novelty of this framework lies in two key aspects: firstly it integrates essential open-source modelling tools covering energy end uses in buildings technology performance and cost and energy system design optimisation into a unified and easily-reproducible framework. Secondly it introduces a novel optimisation tool with a concise and generic mathematical formulation capable of modelling multi-energy vector systems capturing interdependencies between different energy vectors and technologies. The model formulation which captures both short- and long-term energy storage facilitates the identification of smart design and operation strategies with low computational cost. Different building energy demand and price scenarios are investigated and the economic and energy benefits of using a holistic multi-energy-vector approach are quantified. Technology combinations under consideration include: (i) a photovoltaic-electric heat pump-battery system (ii) a photovoltaic-electric heat pump-battery-hot water cylinder system (iii) a photovoltaic-electrolyser‑hydrogen storage-fuel cell system and (iv) a system with all above technology options. Using a university building as a case study it is shown that the smart integration of electricity heating cooling and hydrogen generation and storage technologies results in a total system cost which is >25% lower than the scenario of only importing grid electricity and using a fuel oil boiler. The battery mitigates intra-day fluctuations in electricity demand and the hot-water cylinder allows for efficiently managing heat demand with a small heat pump. In order to avoid PV curtailment excess PV-generated electricity can also be stored in the form of green hydrogen providing a long-term energy storage solution spanning days weeks or even seasons. Results are useful for end-users investment decision makers and energy policy makers when selecting building-integrated low-carbon technologies and relevant policies.
Enabling Safe and Sustainable Hydrogen Mobility: Circular Economy-Driven Management of Hydrogen Vehicle Safety
Sep 2023
Publication
Hydrogen vehicles encompassing fuel cell electric vehicles (FCEVs) are pivotal within the UK’s energy landscape as it pursues the goal of net-zero emissions by 2050. By markedly diminishing dependence on fossil fuels FCEVs including hydrogen vehicles wield substantial influence in shaping the circular economy (CE). Their impact extends to optimizing resource utilization enabling zero-emission mobility facilitating the integration of renewable energy sources supplying adaptable energy storage solutions and interconnecting diverse sectors. The widespread adoption of hydrogen vehicles accelerates the UK’s transformative journey towards a sustainable CE. However to fully harness the benefits of this transition a robust investigation and implementation of safety measures concerning hydrogen vehicle (HV) use are indispensable. Therefore this study takes a holistic approach integrating quantitative risk assessment (QRA) and an adaptive decision-making trial and evaluation laboratory (DEMATEL) framework as pragmatic instruments. These methodologies ensure both the secure deployment and operational excellence of HVs. The findings underscore that the root causes of HV failures encompass extreme environments material defects fuel cell damage delivery system impairment and storage system deterioration. Furthermore critical driving factors for effective safety intervention revolve around cultivating a safety culture robust education/training and sound maintenance scheduling. Addressing these factors is pivotal for creating an environment conducive to mitigating safety and risk concerns. Given the intricacies of conducting comprehensive hydrogen QRAs due to the absence of specific reliability data this study dedicates attention to rectifying this gap. A sensitivity analysis encompassing a range of values is meticulously conducted to affirm the strength and reliability of our approach. This robust analysis yields precise dependable outcomes. Consequently decision-makers are equipped to discern pivotal underlying factors precipitating potential HV failures. With this discernment they can tailor safety interventions that lay the groundwork for sustainable resilient and secure HV operations. Our study navigates the intersection of HVs safety and sustainability amplifying their importance within the CE paradigm. Using the careful amalgamation of QRA and DEMATEL methodologies we chart a course towards empowering decision-makers with the insights to steer the hydrogen vehicle domain to safer horizons while ushering in an era of transformative eco-conscious mobility.
H21 Phase 2 Technical Summary Report
Jul 2023
Publication
The H21 Phase 2 research will provide vital evidence both towards the hydrogen village trial and potential town scale pilots and to the Government which is aiming to make a decision about the use of hydrogen for home heating by 2026.
The key objectives of the H21 Phase 2 NIC project were to further develop the evidence base supporting conversion of the natural gas distribution network to 100% hydrogen. The key principles of H21 NIC Phase 2 were to:
→ Confirm how we can manage and operate the network safely through an appraisal of existing network equipment procedures and network modelling tools.
→ Validate network operations on a purpose-built below 7 barg network as well as an existing unoccupied buried network and provide a platform to publicise and demonstrate a hydrogen network in action.
→ Develop a combined distribution network and downstream Quantitative Risk Assessment (QRA) for 100% hydrogen by further developing the work undertaken on the H21 Phase 1 QRA and the Hy4Heat ‘downstream of ECV’ QRA.
→ Continue to understand how consumers could be engaged with ahead of a conversion. This programme was split into four phases detailed below:
→ Phase 2a – Appraisal of Network 0-7 bar Operations
→ Phase 2b – Unoccupied Network Trials
→ Phase 2c – Combined QRA
→ Phase 2d – Social Sciences
The project with the support of the HSE’s Science & Research Centre (HSE S&RC) and DNV successfully undertook a programme of work to review the NGN below 7 barg network operating procedures. The project implemented testing and demonstrations on the Phase 2a Microgrid at DNV Spadeadam and Phase 2b Unoccupied Trial site in South Bank on a repurposed NGN network to provide and demonstrate the supporting evidence for the required changes to procedures. Details of the outputs of the HSE S&RC procedure review and the evidence collected by DNV from the testing and demonstration projects is provided in detail in this technical summary report.
Due to the differences in gas characteristics between hydrogen and natural gas changes will be required to some of the operational and maintenance procedures the evidence of which is provided in this report. The Gas Distribution Networks (GDNs) will need to review the findings from this project when implementing the required changes to their operational and maintenance procedures.
The key objectives of the H21 Phase 2 NIC project were to further develop the evidence base supporting conversion of the natural gas distribution network to 100% hydrogen. The key principles of H21 NIC Phase 2 were to:
→ Confirm how we can manage and operate the network safely through an appraisal of existing network equipment procedures and network modelling tools.
→ Validate network operations on a purpose-built below 7 barg network as well as an existing unoccupied buried network and provide a platform to publicise and demonstrate a hydrogen network in action.
→ Develop a combined distribution network and downstream Quantitative Risk Assessment (QRA) for 100% hydrogen by further developing the work undertaken on the H21 Phase 1 QRA and the Hy4Heat ‘downstream of ECV’ QRA.
→ Continue to understand how consumers could be engaged with ahead of a conversion. This programme was split into four phases detailed below:
→ Phase 2a – Appraisal of Network 0-7 bar Operations
→ Phase 2b – Unoccupied Network Trials
→ Phase 2c – Combined QRA
→ Phase 2d – Social Sciences
The project with the support of the HSE’s Science & Research Centre (HSE S&RC) and DNV successfully undertook a programme of work to review the NGN below 7 barg network operating procedures. The project implemented testing and demonstrations on the Phase 2a Microgrid at DNV Spadeadam and Phase 2b Unoccupied Trial site in South Bank on a repurposed NGN network to provide and demonstrate the supporting evidence for the required changes to procedures. Details of the outputs of the HSE S&RC procedure review and the evidence collected by DNV from the testing and demonstration projects is provided in detail in this technical summary report.
Due to the differences in gas characteristics between hydrogen and natural gas changes will be required to some of the operational and maintenance procedures the evidence of which is provided in this report. The Gas Distribution Networks (GDNs) will need to review the findings from this project when implementing the required changes to their operational and maintenance procedures.
Assessment of Hydrogen Gas Turbine-fuel Cell Powerplant for Rotorcraft
Jul 2023
Publication
Conventional turboshaft engines are high power density movers suffering from low efficiency at part power operation and producing significant emissions. This paper presents a design exploration and feasibility assessment of a hybrid hydrogen-fueled powerplant for Urban Air Mobility (UAM) rotorcraft. A multi-disciplinary approach is devised comprising models for rotorcraft performance tank and subsystems sizing and engine performance. The respective trade-offs between payload-range and mission level performance are quantified for kerosene-fueled and hybrid hydrogen tilt-rotor variants. The effects of gas turbine scaling and fuel cell pressurization are evaluated for different hybridization degrees. Gas turbine scaling with hybridization (towards the fuel cell) results in up to 21% benefit in energy consumption relative to the non-scaled case with the benefits being more pronounced at high hybridization degrees. Pressurizing the fuel cell has shown significant potential as cell efficiency can increase up to 10% when pressurized to 6 bar which translates to a 6% increase in overall efficiency. The results indicate that current fuel cells (1 kW/kg) combined with current hydrogen tank technology severely limit the payload range capability of the tilt-rotor. However for advanced fuel cell technology (2.5 kW/kg) and low ranges hybrid powerplant show the potential to reduce energy consumption and reduce emissions footprint.
Modelling Large-scale Hydrogen Uptake in the Mexican Refinery and Power Sectors
Sep 2023
Publication
Due to the emissions reduction commitments that Mexico compromised in the Paris Agreement several clean fuel and renewable energy technologies need to penetrate the market to accomplish the environmental goals. Therefore there is a need to develop achievable and realistic policies for such technologies to ease the decision-making on national energy strategies. Several countries are starting to develop large-scale green hydrogen production projects to reduce the carbon footprint of the multiple sectors within the country. The conversion sectors namely power and refinery are fundamental sectors to decarbonise due to their energy supply role. Nowadays the highest energy consumables of the country are hydrocarbons (more than 90%) causing a particular challenge for deep decarbonisation. The purpose of this study is to use a multi-regional energy system model of Mexico to analyse a decarbonisation scenario in line with the latest National Energy System Development Program. Results show that if the country wants to succeed in reducing 22% of its GHG emissions and 51% of its short-lived climate pollutants emissions green hydrogen could play a role in power generation in regions with higher energy demand growth rates. These results show regarding the power sector that H2 could represent 13.8 GW or 5.1% of the total installed capacity by 2050 while for the refinery sector H2 could reach a capacity of 157 PJ/y which is around 31.8% of the total share and it is mainly driven by the increasing demands of the transport industry and power sectors. Nevertheless as oil would still represent the largest energy commodity CCS technologies would have to be deployed for new and retrofitted refinery facilities.
Cushion Gas in Hydrogen Storage—A Costly CAPEX or a Valuable Resource for Energy Crises?
Dec 2022
Publication
The geological storage of hydrogen is a seasonal energy storage solution and the storage capacity of saline aquifers is most appropriately defined by quantifying the amount of hydrogen that can be injected and reproduced over a relevant time period. Cushion gas stored in the reservoir to support the production of the working gas is a CAPEX which should be reduced to decrease implementation cost for gas storage. The cushion gas to working gas ratio provides a sufficiently accurate reflection of the storage efficiency with higher ratios equating to larger initial investments. This paper investigates how technical measures such as well configurations and adjustments to the operational size and schedule can reduce this ratio and the outcomes can inform optimisation strategies for hydrogen storage operations. Using a simplified open saline aquifer reservoir model hydrogen storage is simulated with a single injection and production well. The results show that the injection process is more sensitive to technical measures than the production process; a shorter perforation and a smaller well diameter increases the required cushion gas for the injection process but has little impact on the production. If the storage operation capacity is expanded and the working gas volume increased the required cushion gas to working gas ratio increases for injection reducing the efficiency of the injection process. When the reservoir pressure has more time to equilibrate less cushion gas is required. It is shown that cushion gas plays an important role in storage operations and that the tested optimisation strategies impart only minor effects on the production process however there is significant need for careful optimisation of the injection process. It is suggested that the recoverable part of the cushion gas could be seen as a strategic gas reserve which can be produced during an energy crisis. In this scenario the recoverable cushion gas could be owned by the state and the upfront costs for gas storage to the operator would be reduced making the implementation of more gas storage and the onset of hydrogen storage more attractive to investors.
Multi-port Coordination: Unlocking Flexibility and Hydrogen Opportunities in Green Energy Networks
Mar 2024
Publication
Seaports are responsible for consuming a large amount of energy and producing a sizeable amount of environmental emissions. However optimal coordination and cooperation present an opportunity to transform this challenge into an opportunity by enabling flexibility in their generation and load units. This paper introduces a coordination framework for exploiting flexibility across multiple ports. The proposed method fosters cooperation between ports in achieving lower environmental emissions while leveraging flexibility to increase their revenue. This platform allows ports to participate in providing flexibility for the energy grid through the introduction of a green port-to-grid concept while optimising their cooperation. Furthermore the proximity to offshore wind farms is considered an opportunity for the ports to investigate their role in harnessing green hydrogen. The proposed method explores the hydrogen storage capability of ports as an opportunity for increasing the techno-economic benefits particularly through coupling them with offshore wind farms. Compared to existing literature the proposed method enjoys a comprehensive logistics-electric model for the ports a novel coordination framework for multi-port flexibility and the potentials of hydrogen storage for the ports. These unique features position this paper a valuable reference for research and industry by demonstrating realistic cooperation among ports in the energy network. The simulation results confirm the effectiveness of the proposed port flexibility coordination from both environmental and economic perspectives.
Research Progress, Trends, and Current State of Development on PEMFC-New Insights from a Bibliometric Analysis and Characteristics of Two Decades of Research Output
Nov 2022
Publication
The consumption of hydrogen could increase by sixfold in 2050 compared to 2020 levels reaching about 530 Mt. Against this backdrop the proton exchange membrane fuel cell (PEMFC) has been a major research area in the field of energy engineering. Several reviews have been provided in the existing corpus of literature on PEMFC but questions related to their evolutionary nuances and research hotspots remain largely unanswered. To fill this gap the current review uses bibliometric analysis to analyze PEMFC articles indexed in the Scopus database that were published between 2000–2021. It has been revealed that the research field is growing at an annual average growth rate of 19.35% with publications from 2016 to 2012 alone making up 46% of the total articles available since 2000. As the two most energy-consuming economies in the world the contributions made towards the progress of PEMFC research have largely been from China and the US. From the research trend found in this investigation it is clear that the focus of the researchers in the field has largely been to improve the performance and efficiency of PEMFC and its components which is evident from dominating keywords or phrases such as ‘oxygen reduction reaction’ ‘electrocatalysis’ ‘proton exchange membrane’ ‘gas diffusion layer’ ‘water management’ ‘polybenzimidazole’ ‘durability’ and ‘bipolar plate’. We anticipate that the provision of the research themes that have emerged in the PEMFC field in the last two decades from the scientific mapping technique will guide existing and prospective researchers in the field going forward.
Maximizing Green Hydrogen Production from Water Electrocatalysis: Modeling and Optimization
Mar 2023
Publication
The use of green hydrogen as a fuel source for marine applications has the potential to significantly reduce the carbon footprint of the industry. The development of a sustainable and cost-effective method for producing green hydrogen has gained a lot of attention. Water electrolysis is the best and most environmentally friendly method for producing green hydrogen-based renewable energy. Therefore identifying the ideal operating parameters of the water electrolysis process is critical to hydrogen production. Three controlling factors must be appropriately identified to boost hydrogen generation namely electrolysis time (min) electric voltage (V) and catalyst amount (µg). The proposed methodology contains the following two phases: modeling and optimization. Initially a robust model of the water electrolysis process in terms of controlling factors was established using an adaptive neuro-fuzzy inference system (ANFIS) based on the experimental dataset. After that a modern pelican optimization algorithm (POA) was employed to identify the ideal parameters of electrolysis duration electric voltage and catalyst amount to enhance hydrogen production. Compared to the measured datasets and response surface methodology (RSM) the integration of ANFIS and POA improved the generated hydrogen by around 1.3% and 1.7% respectively. Overall this study highlights the potential of ANFIS modeling and optimal parameter identification in optimizing the performance of solar-powered water electrocatalysis systems for green hydrogen production in marine applications. This research could pave the way for the more widespread adoption of this technology in the marine industry which would help to reduce the industry’s carbon footprint and promote sustainability.
Ammonia, Methane and Hydrogen for Gas Turbines
Aug 2015
Publication
Ammonia has been identified as a sustainable fuel for transport and power applications. Similar to hydrogen ammonia is a synthetic product that can be obtained either from fossil fuels biomass or other renewable sources. Since the 1960’s considerable research has taken place to develop systems capable of burning the material in gas turbines. However it is not until recently that interest in ammonia has regained some momentum in the energy agenda as it is a carbon free carrier and offers an energy density higher than compressed hydrogen. . Therefore this work examines combustion stability and emissions from gaseous ammonia blended with methane or hydrogen in gas turbines. Experiments were carried out in a High Pressure Combustion Rig under atmospheric conditions employing a bespoke generic swirl burner. OH* Chemiluminescense was used for all trials to determine reactivity of the radical. Emissions were measured and correlated to equilibrium calculations using GASEQ. Results show that efficient combustion can be achieved with high power but at very narrow equivalence ratios using both hydrogen and methane blends. Moreover low concentrations of OH radicals are observed at high hydrogen content probably as a consequence of the high NH2 production.
The ATHENA Framework: Analysis and Design of a Strategic Hydrogen Refuelling Infrastructure
Apr 2023
Publication
With the pressured timescale in determining effective and viable net zero solutions within the transport sector it is important to understand the extent of implementing a new refuelling infrastructure for alternative fuel such as hydrogen. The proposed ATHENA framework entails three components which encapsulates the demand data analysis an optimisation model in determining the minimal cost hydrogen refuelling infrastructure design and an agent-based model simulating the operational system. As a case study the ATHENA framework is applied to Northern England focusing on the design of a hydrogen refuelling infrastructure for heavy goods vehicles. Analysis is performed in calibrating parameters and investigating different scenarios within the optimisation and agent-based simulation models. For this case study the system optimality is limited by the feasible number of tube trailer deliveries per day which suggests an opportunity for alternative delivery methods.
Assessing the Pressure Losses during Hydrogen Transport in the Current Natural Gas Infrastructure Using Numerical Modelling
May 2023
Publication
The UK government aims to transition its modern natural gas infrastructure towards Hydrogen by 2035. Since hydrogen is a much lighter gas than methane it is important to understand the change in parameters when transporting it. While most modern work in this topic looks at the transport of hydrogen-methane mixtures this work focuses on pure hydrogen transport. The aim of this paper is to highlight the change in gas distribution parameters when natural gas is replaced by hydrogen in the existing infrastructure. This study uses analytical models and computational models to compare the flow of hydrogen and methane in a pipe based on pressure loss. The Darcy-Weisbach and Colebrook-White equations were used for the analytical models and the k- ε model was used for the computational approach. The variables considered in the comparison were the pipe material (X52 Steel and MDPE) and pipe diameters (0.01m–1m). It was observed that hydrogen had to be transported 250–270% the velocity of methane to replicate flow for a fixed length of pipe. Furthermore it was noted that MDPE pipes has 2–31% lower pressure losses compared to X52 steel for all diameters when transporting hydrogen at a high velocity. Lastly it was noted that the analytical model and computational model were in agreement with 1–5% error in their findings.
Two-Layer Optimization Planning Model for Integrated Energy Systems in Hydrogen Refueling Original Station
May 2023
Publication
With the aggravation of global environmental pollution problems and the need for energy restructuring hydrogen energy as a highly clean resource has gradually become a hot spot for research in countries around the world. Facing the requirement of distributed hydrogen in refueling the original station for hydrogen transportation and other usage this paper proposes a comprehensive energy system planning model for hydrogen refueling stations to obtain the necessary devices construction the devices’ capacity decisions and the optimal operation behaviors of each device. Comparing to traditional single hydrogen producing technics in the traditional planning model the proposed model in this paper integrates both water-electrolysis-based and methanol-based manufacturing technics. A two-level optimization model is designed for this comprehensive system. The result of the numerical study shows that the proposed model can achieve a better optimal solution for distributed hydrogen production. Also it considers the single producing situation when price of one primary resource is sufficient higher than the other.
Expert Perceptions of Game-changing Innovations towards Net Zero
Dec 2022
Publication
Current technological improvements are yet to put the world on track to net-zero which will require the uptake of transformative low-carbon innovations to supplement mitigation efforts. However the role of such innovations is not yet fully understood; some of these ‘miracles’ are considered indispensable to Paris Agreement-compliant mitigation but their limitations availability and potential remain a source of debate. We evaluate such potentially game-changing innovations from the experts’ perspective aiming to support the design of realistic decarbonisation scenarios and better-informed net-zero policy strategies. In a worldwide survey 260 climate and energy experts assessed transformative innovations against their mitigation potential at-scale availability and/or widescale adoption and risk of delayed diffusion. Hierarchical clustering and multi-criteria decision-making revealed differences in perceptions of core technological innovations with next generation energy storage alternative building materials iron-ore electrolysis and hydrogen in steelmaking emerging as top priorities. Instead technologies highly represented in well-below-2◦C scenarios seemingly feature considerable and impactful delays hinting at the need to re-evaluate their role in future pathways. Experts’ assessments appear to converge more on the potential role of other disruptive innovations including lifestyle shifts and alternative economic models indicating the importance of scenarios including non-technological and demand-side innovations. To provide insights for expert elicitation processes we finally note caveats related to the level of representativeness among the 260 engaged experts the level of their expertise that may have varied across the examined innovations and the potential for subjective interpretation to which the employed linguistic scales may be prone to.
HyDeploy2 Project: Winlaton Trial Report
Sep 2022
Publication
The HyDeploy project seeks to address a key issue for UK customers and UK energy policy makers: how to reduce the carbon emitted from heating homes. The UK has a world class gas distribution grid delivering heat conveniently and safely to over 83% of homes. Emissions can be reduced by lowering the carbon content of gas through blending with hydrogen. This delivers carbon savings without customers requiring disruptive and expensive changes in their homes. It also provides the platform for deeper carbon savings by enabling wider adoption of hydrogen across the energy system. HyDeploy has previously delivered a successful trial demonstrations of repurposing existing UK distribution gas networks (Keele University) to operate on a blend of natural gas and hydrogen (up to 20% mol/mol) showing that carbon savings can be made through the gas networks today whilst continuing to meet the needs of gas consumers without introducing any disruptions.<br/>The ultimate objective of the HyDeploy programme is to see the roll-out of hydrogen blends across the GB gas distribution network unlocking 35 TWh pa of low carbon heat - the equivalent of removing 2.5 million fossil-fuelled cars off the roads. To achieve this the next phase of the programme is to address the remaining evidence gaps that had not been covered by the trial demonstration programmes.<br/>The demonstrations have focussed on the low and medium pressure tiers of the gas distribution network (i.e. injecting into a 2 bar gauge pressure network and distributing the blended gas down to the low pressure network and into people’s homes and commercial buildings and businesses) and predominantly serving domestic appliances.<br/>The remainder of the HyDeploy2 programme will generate an evidence base for GB’s gas distribution network which includes demonstrating the suitability of using hydrogen blended gas in the fields of industrial and commercial users and the performance of materials assets and procedures on the higher pressure tiers (i.e. 7 bar gauge operation and above).<br/>This report captures the details of the Winlaton trial and provides a future look to how the UK can transition from successful hydrogen blending trials to roll-out.
A Review of Liquid Hydrogen Aircraft and Propulsion Technologies
Jan 2024
Publication
Sustainable aviation is a key part of achieving Net Zero by 2050 and is arguably one of the most challenging sectors to decarbonise. Hydrogen has gained unprecedented attention as a future fuel for aviation for use within fuel cell or hydrogen gas turbine propulsion systems. This paper presents a survey of the literature and industrial projects on hydrogen aircraft and associated enabling technologies. The current and predicted technology capabilities are analysed to identify important trends and to assess the feasibility of hydrogen propulsion. Several key enabling technologies are discussed in detail and gaps in knowledge are identified. It is evident that hydrogen propelled aircraft are technologically viable by 2050. However convergence of a number of critical factors is required namely: the extent of industrial collaboration the understanding of environmental science and contrails green hydrogen production and its availability at the point of use and the safety and certification of the aircraft and supporting infrastructure.
Natural Hydrogen in the Energy Transition: Fundamentals, Promise, and Enigmas
Oct 2023
Publication
Beyond its role as an energy vector a growing number of natural hydrogen sources and reservoirs are being discovered all over the globe which could represent a clean energy source. Although the hydrogen amounts in reservoirs are uncertain they could be vast and they could help decarbonize energy-intensive economic sectors and facilitate the energy transition. Natural hydrogen is mainly produced through a geochemical process known as serpentinization which involves the reaction of water with low-silica ferrous minerals. In favorable locations the hydrogen produced can become trapped by impermeable rocks on its way to the atmosphere forming a reservoir. The safe exploitation of numerous natural hydrogen reservoirs seems feasible with current technology and several demonstration plants are being commissioned. Natural hydrogen may show variable composition and require custom separation purification storage and distribution facilities depending on the location and intended use. By investing in research in the mid-term more hydrogen sources could become exploitable and geochemical processes could be artificially stimulated in new locations. In the long term it may be possible to leverage or engineer the interplay between microorganisms and geological substrates to obtain hydrogen and other chemicals in a sustainable manner.
Review of the Production of Turquoise Hydrogen from Methane Catalytic Decomposition: Optimising Reactors for Sustainable Hydrogen Production
May 2024
Publication
Hydrogen is gaining prominence in global efforts to combat greenhouse gas emissions and climate change. While steam methane reforming remains the predominant method of hydrogen production alternative approaches such as water electrolysis and methane cracking are gaining attention. The bridging technology – methane cracking – has piqued scientific interest with its lower energy requirement (74.8 kJ/mol compared to steam methane reforming 206.278 kJ/mol) and valuable by-product of filamentous carbon. Nevertheless challenges including coke formation and catalyst deactivation persist. This review focuses on two main reactor types for catalytic methane decomposition – fixed-bed and fluidised bed. Fixed-bed reactors excel in experimental studies due to their operational simplicity and catalyst characterisation capabilities. In contrast fluidised-bed reactors are more suited for industrial applications where efforts are focused on optimising the temperature gas flow rate and particle characterisation. Furthermore investigations into various fluidised bed regimes aim to identify the most suitable for potential industrial deployment providing insights into the sustainable future of hydrogen production. While the bubbling regime shows promise for upscaling fluidised bed reactors experimental studies on turbulent fluidised-bed reactors especially in achieving high hydrogen yield from methane cracking are limited highlighting the technology’s current status not yet reaching commercialisation.
Visualisation and Quantification of Wind-induced Variability in Hydrogen Clouds Following Releases of Liquid Hydrogen
Sep 2023
Publication
Well characterized experimental data for consequence model validation is important in progressing the use of liquid hydrogen as an energy carrier. In 2019 the Health and Safety Executive (HSE) undertook a series of liquid hydrogen dispersion and combustion experiments as a part of the Pre-normative Research for Safe Use of Liquid Hydrogen (PRESLHY) project. In partnership between the National Renewable Energy Laboratory (NREL) and HSE time and spatially varying hydrogen concentration measurements were made in 25 dispersion experiments and 23 congested ignition experiments associated with PRESLHY WP3 and WP5 respectively. These measurements were undertaken using the hydrogen wide area monitoring system developed by NREL. During the 23 congested ignition experiments high variability was observed in the measured explosion severity during experiments with similar initial conditions. This led to the conclusion that wind including localized gusts had a large influence on the dispersion of the hydrogen and therefore the quantity of hydrogen that was present in the congested region of the explosions. Using the hydrogen concentration measurements taken immediately prior to ignition the hydrogen clouds were visualized in an attempt to rationalize the variability in overpressure between the tests. Gaussian process regression was applied to quantify the variability of the measured hydrogen concentrations. This analysis could also be used to guide modifications in experimental designs for future research on hydrogen combustion behavior.
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