Publications
Techno-economic Optimization of Green HydrogenProduction from Curtailed Power in Ireland: Impact of Future Future Renewable Energy Installations, Weather Variability, and Grid Constraints
Jul 2025
Publication
To improve the economic viability of renewable (green) hydrogen production excess renewable energy which cannot be input to the electricity grid (curtailed power) can be utilized. While several models have attempted to optimize hydrogen production using curtailed power several factors must be considered in greater detail including the impacts of future renewable energy capacity weather variability and electricity grid constraints. This study aims to explore these aspects through an integrated model performing a techno-economic assessment and size optimization in order to achieve the minimum levelized cost of hydrogen (LCOH). Based on the Irish case optimizing the production of hydrogen from curtailed power results in a minimum LCOH of 1.20–9.39 €/kg. To maximize variable renewable energy penetration in the grid while allowing for low-cost hydrogen production from curtailed power it is suggested to focus on grid improvements while ensuring rapid commissioning of offshore wind installations leading to a LCOH of 1.26–2.44 €/kg.
Experimental Evaluation of Dynamic Operating Concepts for Alkaline Water Electrolyzers Powered by Renewable Energy
Dec 2021
Publication
Synthetic current density profiles with wind and photovoltaic power characteristics were calculated by autoregressive-moving-average (ARMA) models for the experimental evaluation of dynamic operating concepts for alkaline water electrolyzers powered by renewable energy. The selected operating concepts included switching between mixed and split electrolyte cycles and adapting the liquid electrolyte volume flow rate depending on the current density. All experiments were carried out at a pressure of 7 bar a temperature of 60 °C and with an aqueous potassium hydroxide solution with 32 wt.% KOH as the electrolyte. The dynamic operating concepts were compared to stationary experiments with mixed electrolyte cycles and the experimental evaluation showed that the selected operating concepts were able to reduce the gas impurity compared to the reference operating conditions without a noticeable increase of the cell potential. Therefore the overall system efficiency and process safety could be enhanced by this approach.
U.S. National Clean Hydrogen Strategy and Roadmap
Jun 2023
Publication
The U.S. National Clean Hydrogen Strategy and Roadmap explores opportunities for clean hydrogen to contribute to national decarbonization goals across multiple sectors of the economy. It provides a snapshot of hydrogen production transport storage and use in the United States today and presents a strategic framework for achieving large-scale production and use of clean hydrogen examining scenarios for 2030 2040 and 2050.
The Strategy and Roadmap also identifies needs for collaboration among federal government agencies industry academia national laboratories state local and Tribal communities environmental and justice communities labor unions and numerous stakeholder groups to accelerate progress and market liftoff. This roadmap establishes concrete targets market-driven metrics and tangible actions to measure success across sectors.
The Strategy and Roadmap responds to legislative language set forth in section 40314 of the Infrastructure Investment and Jobs Act (Public Law 117-58) also known as the Bipartisan Infrastructure Law (BIL). This document was posted for in draft form for public comment in September 2022 and the final version of the report was informed by stakeholder feedback further analysis on market liftoff as well as engagement across several federal agencies and the White House Climate Policy Office. There will also be future opportunities for stakeholder feedback as the report will be updated at least every three years as required by the BIL.
The report can be found on their website.
The Strategy and Roadmap also identifies needs for collaboration among federal government agencies industry academia national laboratories state local and Tribal communities environmental and justice communities labor unions and numerous stakeholder groups to accelerate progress and market liftoff. This roadmap establishes concrete targets market-driven metrics and tangible actions to measure success across sectors.
The Strategy and Roadmap responds to legislative language set forth in section 40314 of the Infrastructure Investment and Jobs Act (Public Law 117-58) also known as the Bipartisan Infrastructure Law (BIL). This document was posted for in draft form for public comment in September 2022 and the final version of the report was informed by stakeholder feedback further analysis on market liftoff as well as engagement across several federal agencies and the White House Climate Policy Office. There will also be future opportunities for stakeholder feedback as the report will be updated at least every three years as required by the BIL.
The report can be found on their website.
Multi-option Analytical Modeling of Levelised Costs Across Various Hydrogen Supply Chain Nodes
May 2024
Publication
Hydrogen is envisioned to become a fundamental energy vector for the decarbonization of energy systems. Two key factors that will define the success of hydrogen are its sustainability and competitiveness with alternative solutions. One of the many challenges for the proliferation of hydrogen is the creation of a sustainable supply chain. In this study a methodology aimed at assessing the economic feasibility of holistic hydrogen supply chains is developed. Based on the designed methodology a tool which calculates the levelized cost of hydrogen for the different stages of its supply chain: production transmission & distribution storage and conversion is proposed. Each stage is evaluated individually combining relevant technical and economic notions such as learning curves and scaling factors. Subsequently the findings from each stage are combined to assess the entire supply chain as a whole. The tool is then applied to evaluate case studies of various supply chains including large-scale remote and small-scale distributed green hydrogen supply chains as well as conventional steam methane reforming coupled with carbon capture and storage technologies. The results show that both green hydrogen supply chains and conventional methods can achieve a competitive LCOH of around €4/kg in 2030. However the key contribution of this study is the development of the tool which provides a foundation for a comprehensive evaluation of hydrogen supply chains that can be continuously improved through the inputs of additional users and further research on one or more of the interconnected stages.
The Status of On-Board Hydrogen Storage in Fuel Cell Electric Vehicles
Aug 2023
Publication
Hydrogen as an energy carrier could help decarbonize industrial building and transportation sectors and be used in fuel cells to generate electricity power or heat. One of the numerous ways to solve the climate crisis is to make the vehicles on our roads as clean as possible. Fuel cell electric vehicles (FCEVs) have demonstrated a high potential in storing and converting chemical energy into electricity with zero carbon dioxide emissions. This review paper comprehensively assesses hydrogen’s potential as an innovative alternative for reducing greenhouse gas (GHG) emissions in transportation particularly for on-board applications. To evaluate the industry’s current status and future challenges the work analyses the technology behind FCEVs and hydrogen storage approaches for on-board applications followed by a market review. It has been found that to achieve long-range autonomy (over 500 km) FCEVs must be capable of storing 5–10 kg of hydrogen in compressed vessels at 700 bar with Type IV vessels being the primary option in use. Carbon fiber is the most expensive component in vessel manufacturing contributing to over 50% of the total cost. However the cost of FCEV storage systems has considerably decreased with current estimates around 15.7 $/kWh and is predicted to drop to 8 $/kWh by 2030. In 2021 Toyota Hyundai Mercedes-Benz and Honda were the major car brands offering FCEV technology globally. Although physical and chemical storage technologies are expected to be valuable to the hydrogen economy compressed hydrogen storage remains the most advanced technology for on-board applications.
Feasibility Study into Water Requirement for Hydrogen Production
Nov 2022
Publication
Low carbon hydrogen can be produced by a variety of processes that require substantial quantities of water. Several major hydrogen projects are proposed in Scotland; as an energy storage medium allowing new renewable power capacity to operate and as a direct alternative to displace natural gas as a primary fuel source. The additional water consumption associated with these hydrogen projects presents an infrastructure challenge.
The aims of the study are to evaluate the water requirements of new hydrogen production facilities and the associated implications for water infrastructure and to develop a strategic framework for assessing these aspects of hydrogen projects throughout the UK. The initial focus of the study is on Scotland; however the methodology developed in the project will be used throughout the UK
Benefits
Low carbon hydrogen can be produced by a variety of processes all of which require substantial quantities of water. Several major hydrogen projects are proposed in Scotland; both as an energy storage medium allowing new renewable power capacity (particularly wind) to operate and as a direct alternative to displace natural gas as a primary fuel source. The additional water consumption associated with these hydrogen projects presents an infrastructure challenge e.g. the Scottish Environment Protection Agency (SEPA) recently highlighted Scotland’s vulnerability to dry weather and climate-induced changes in the availability and functioning of water resources.
The project in partnership with Ramboll will look to deliver a technical assessment and feasibility study into water requirements for hydrogen production in Scotland. The aims of the study are to evaluate the water requirements of new hydrogen production facilities and the associated implications for water infrastructure and to develop a strategic framework for assessing these aspects of hydrogen projects throughout the UK. The initial focus of the study is on Scotland; however the methodology developed in the project will be used throughout the UK.
The research paper can be found on their website.
The aims of the study are to evaluate the water requirements of new hydrogen production facilities and the associated implications for water infrastructure and to develop a strategic framework for assessing these aspects of hydrogen projects throughout the UK. The initial focus of the study is on Scotland; however the methodology developed in the project will be used throughout the UK
Benefits
Low carbon hydrogen can be produced by a variety of processes all of which require substantial quantities of water. Several major hydrogen projects are proposed in Scotland; both as an energy storage medium allowing new renewable power capacity (particularly wind) to operate and as a direct alternative to displace natural gas as a primary fuel source. The additional water consumption associated with these hydrogen projects presents an infrastructure challenge e.g. the Scottish Environment Protection Agency (SEPA) recently highlighted Scotland’s vulnerability to dry weather and climate-induced changes in the availability and functioning of water resources.
The project in partnership with Ramboll will look to deliver a technical assessment and feasibility study into water requirements for hydrogen production in Scotland. The aims of the study are to evaluate the water requirements of new hydrogen production facilities and the associated implications for water infrastructure and to develop a strategic framework for assessing these aspects of hydrogen projects throughout the UK. The initial focus of the study is on Scotland; however the methodology developed in the project will be used throughout the UK.
The research paper can be found on their website.
Reversible Molten Catalytic Methane Cracking Applied to Commercial Solar-Thermal Receivers
Nov 2020
Publication
When driven by sunlight molten catalytic methane cracking can produce clean hydrogen fuel from natural gas without greenhouse emissions. To design solar methane crackers a canonical plug flow reactor model was developed that spanned industrially relevant temperatures and pressures (1150–1350 Kelvin and 2–200 atmospheres). This model was then validated against published methane cracking data and used to screen power tower and beam-down reactor designs based on “Solar Two” a renewables technology demonstrator from the 1990s. Overall catalytic molten methane cracking is likely feasible in commercial beam-down solar reactors but not power towers. The best beam-down reactor design was 9% efficient in the capture of sunlight as fungible hydrogen fuel which approaches photovoltaic efficiencies. Conversely the best discovered tower methane cracker was only 1.7% efficient. Thus a beam-down reactor is likely tractable for solar methane cracking whereas power tower configurations appear infeasible. However the best simulated commercial reactors were heat transfer limited not reaction limited. Efficiencies could be higher if heat bottlenecks are removed from solar methane cracker designs. This work sets benchmark conditions and performance for future solar reactor improvement via design innovation and multiphysics simulation.
Integration of Air-cooled Multi-stack Polymer Electrolyte Fuel Cell Systems into Renewable Microgrids
May 2022
Publication
Currently there is a growing interest in increasing the power range of air-cooled fuel cells (ACFCs) as they are cheaper easier to use and maintain than water-cooled fuel cells (WCFCs). However air-cooled stacks are only available up to medium power (<10 kW). Therefore a good solution may be the development of ACFCs consisting of several stacks until the required power output is reached. This is the concept of air-cooled multi-stack fuel cell (AC-MSFC). The objective of this work is to develop a turnkey solution for the integration of AC-MSFCs in renewable microgrids specifically those with high-voltage DC (HVDC) bus. This is challenging because the AC-MSFCs must operate in the microgrid as a single ACFC with adjustable power depending on the number of stacks in operation. To achieve this the necessary power converter (ACFCs operate at low voltages so high conversion rates are required) and control loops must be developed. Unlike most designs in the literature the proposed solution is compact forming a system (AC-MSFCS) with a single input (hydrogen) and a single output (high voltage regulated power or voltage) that can be easily integrated into any microgrid and easily scalable depending on the power required. The developed AC-MSFCS integrates stacks balance of plant data acquisition and instrumentation power converters and local controllers. In addition a virtual instrument (VI)has been developed which connected to the energy management system (EMS) of the microgrid allows monitoring of the entire AC-MSFCS (operating temperature purging cell voltage monitoring for degradation evaluation stacks operating point control and alarm and event management) as well as serving as a user interface. This allows the EMS to know the degradation of each stack and to carry out energy distribution strategies or specific maintenance actions which improves efficiency lifespan and of course saves costs. The experimental results have been excellent in terms of the correct operation of the developed AC-MSFCS. Likewise the accumulated degradation of the stacks was quantified showing cells with a degradation of >80%. The excellent electrical and thermal performance of the developed power converter was also validated which allowed the correct and efficient supply of regulated power (average efficiency above 90%) to the HVDC bus according to the power setpoint defined by the EMS of the microgrid.
Exploring the Potential of Green Hydrogen Production and Application in the Antofagasta Region of Chile
Jun 2023
Publication
Green hydrogen is gaining increasing attention as a key component of the global energy transition towards a more sustainable industry. Chile with its vast renewable energy potential is well positioned to become a major producer and exporter of green hydrogen. In this context this paper explores the prospects for green hydrogen production and use in Chile. The perspectives presented in this study are primarily based on a compilation of government reports and data from the scientific literature which primarily offer a theoretical perspective on the efficiency and cost of hydrogen production. To address the need for experimental data an ongoing experimental project was initiated in March 2023. This project aims to assess the efficiency of hydrogen production and consumption in the Atacama Desert through the deployment of a mobile on-site laboratory for hydrogen generation. The facility is mainly composed by solar panels electrolyzers fuel cells and a battery bank and it moves through the Atacama Desert in Chile at different altitudes from the sea level to measure the efficiency of hydrogen generation through the energy approach. The challenges and opportunities in Chile for developing a robust green hydrogen economy are also analyzed. According to the results Chile has remarkable renewable energy resources particularly in solar and wind power that could be harnessed to produce green hydrogen. Chile has also established a supportive policy framework that promotes the development of renewable energy and the adoption of green hydrogen technologies. However there are challenges that need to be addressed such as the high capital costs of green hydrogen production and the need for supportive infrastructure. Despite these challenges we argue that Chile has the potential to become a leading producer and exporter of green hydrogen or derivatives such as ammonia or methanol. The country’s strategic location political stability and strong commitment to renewable energy provide a favorable environment for the development of a green hydrogen industry. The growing demand for clean energy and the increasing interest in decarbonization present significant opportunities for Chile to capitalize on its renewable energy resources and become a major player in the global green hydrogen market.
A Review of Port Decarbonisation Options: Identified Opportunities for Deploying Hydrogen Technologies
Apr 2024
Publication
The utilisation of hydrogen is being explored as a viable solution for reducing carbon emissions in port operations with potential applications in cargo handling transportation and shipping vessel operations. To comprehensively list the decarbonisation options in ports this study conducted a Systematic Literature Review to identify and then survey twelve highly cited review papers. Initially a typology approach was used to categorise the decarbonisation options by activities and technologies. Subsequently the study introduced a novel Port Energy Map to reveal the energy system pathways and their interconnections. Each pathway was then converted into a simpler linear sequence of activities shown as a Port Energy System Taxonomy which outlines the energy supply and energy-using activities. By utilising this taxonomy and map the study identified opportunities and research gaps for integrating hydrogen technologies into port energy systems which serves as a valuable tool for assessing port decarbonisation options.
Work Efficiency and Economic Efficiency of Actual Driving Test of Proton Exchange Membrane Fuel Cell Forklift
Aug 2023
Publication
A 3.5 tonne forklift containing proton exchange membrane fuel cells (PEMFCs) and lithium-ion batteries was manufactured and tested in a real factory. The work efficiency and economic applicability of the PEMFC forklift were compared with that of a lithium-ion battery-powered forklift. The results showed that the back-pressure of air was closely related to the power density of the stack whose stability could be improved by a reasonable control strategy and membrane electrode assemblies (MEAs) with high consistency. The PEMFC powered forklift displayed 40.6% higher work efficiency than the lithium-ion battery-powered forklift. Its lower use-cost compared to internal engine-powered forklifts is beneficial to the commercialization of this product.
Hydrogen Production from Renewable Energy Resources: A Case Study
May 2024
Publication
In the face of increasing demand for hydrogen a feasibility study is conducted on its production by using Renewable Energy Resources (RERs) especially from wind and solar sources with the latter preferring photovoltaic technology. The analysis performed is based on climate data for the Province of Brindisi Apulia Italy. The various types of electrolyzers will be analyzed ultimately choosing the one that best suits the case study under consideration. The technical aspect of the land consumption for RER exploitation until 2050 is analyzed for the Italian case of study and for the Apulia Region. For both the 200 MW and 100 MW RER Power Plants an economic analysis is carried out on the opportunities for using hydrogen. In the last part of the economic analysis the trade-off between the high specific investment cost and the Capacity Factor of Wind technologies is also investigated. The results show the affordability of building high-scale Wind Farms harnessing the existing scale economies. The lowest Hydrogen selling price is achieved by the 200 MW Wind Farms equal to 222 €/MWh against 232 €/MWh of the 200 MW Photovoltaic (PV) Farm. Finally the feasibility analysis considers also the greenhouse gas emission reduction by including in the economic analysis the carbon dioxide (CO2) Average Auction Clearing Price leading for the 200 MW Wind Farms to a hydrogen selling price equal to 191.2 €/MWh against 201 €/MWh of the 200 MW Photovoltaic Farm.
Implementation of Formic Acid as a Liquid Organic Hydrogen Carrier (LOHC): Techno-Economic Analysis and Life Cycle Assessment of Formic Acid Produced via CO2 Utilization
Sep 2022
Publication
To meet the global climate goals agreed upon regarding the Paris Agreement governments and institutions around the world are investigating various technologies to reduce carbon emissions and achieve a net-negative energy system. To this end integrated solutions that incorporate carbon utilization processes as well as promote the transition of the fossil fuel-based energy system to carbon-free systems such as the hydrogen economy are required. One of the possible pathways is to utilize CO2 as the base chemical for producing a liquid organic hydrogen carrier (LOHC) using CO2 as a mediating chemical for delivering H2 to the site of usage since gaseous and liquid H2 retain transportation and storage problems. Formic acid is a probable candidate considering its high volumetric H2 capacity and low toxicity. While previous studies have shown that formic acid is less competitive as an LOHC candidate compared to other chemicals such as methanol or toluene the results were based on out-of-date process schemes. Recently advances have been made in the formic acid production and dehydrogenation processes and an analysis regarding the recent process configurations could deem formic acid as a feasible option for LOHC. In this study the potential for using formic acid as an LOHC is evaluated with respect to the state-of-the-art formic acid production schemes including the use of heterogeneous catalysts during thermocatalytic and electrochemical formic acid production from CO2 . Assuming a hydrogen distribution system using formic acid as the LOHC each of the production transportation dehydrogenation and CO2 recycle sections are separately modeled and evaluated by means of techno-economic analysis (TEA) and life cycle assessment (LCA). Realistic scenarios for hydrogen distribution are established considering the different transportation and CO2 recovery options; then the separate scenarios are compared to the results of a liquefied hydrogen distribution scenario. TEA results showed that while the LOHC system incorporating the thermocatalytic CO2 hydrogenation to formic acid is more expensive than liquefied H2 distribution the electrochemical CO2 reduction to formic acid system reduces the H2 distribution cost by 12%. Breakdown of the cost compositions revealed that reduction of steam usage for thermocatalytic processes in the future can make the LOHC system based on thermocatalytic CO2 hydrogenation to formic acid to be competitive with liquefied H2 distribution if the production cost could be reduced by 23% and 32% according to the dehydrogenation mode selected. Using formic acid as a LOHC was shown to be less competitive compared to liquefied H2 delivery in terms of LCA but producing formic acid via electrochemical CO2 reduction was shown to retain the lowest global warming potential among the considered options.
Calculating the Fundamental Parameters to Assess the Explosion Risk Due to Crossover in Electrolysers
Sep 2023
Publication
With the predicted high demand of hydrogen projected to support the neutral carbon society transition in the coming years the production of hydrogen is set to increase alongside the demand. As electrolysis is set to be amongst the main solutions for green hydrogen production ensuring the safety of electrolysers during operation will become a central concern. This is mainly due to the crossover risk (hydrogen into oxygen or the other way around) in the separators as throughout the years several cases of incidents have been reported. This study aims to evaluate the methodologies for calculating H2/O2 detonation cell size and laminar flame velocity using detailed kinetic mechanisms at the operating conditions of electrolysers (up to 35 bar and 360 K). Therefore the modeling of H2/O2 and H2/Air shock tube delay times and laminar flame speeds at initial different pressures and temperature based on the GRI mech 3.0 [1] Mevel et al.[2] Li et al.[3] Lutz et al. [4] and Burke et al. [5] kinetic mechanisms were performed and compared with the available experimental data in the literature. In each case a best candidate mechanism was then chosen to build a database for the detonation cell size then for the laminar flame speeds up to the operating conditions of electrolysers (293-360K and 1-35 bar).
Green Hydrogen Production through Ammonia Decomposition Using Non-Thermal Plasma
Sep 2023
Publication
Liquid hydrogen carriers will soon play a significant role in transporting energy. The key factors that are considered when assessing the applicability of ammonia cracking in large-scale projects are as follows: high energy density easy storage and distribution the simplicity of the overall process and a low or zero-carbon footprint. Thermal systems used for recovering H2 from ammonia require a reaction unit and catalyst that operates at a high temperature (550–800 ◦C) for the complete conversion of ammonia which has a negative effect on the economics of the process. A non-thermal plasma (NTP) solution is the answer to this problem. Ammonia becomes a reliable hydrogen carrier and in combination with NTP offers the high conversion of the dehydrogenation process at a relatively low temperature so that zero-carbon pure hydrogen can be transported over long distances. This paper provides a critical overview of ammonia decomposition systems that focus on non-thermal methods especially under plasma conditions. The review shows that the process has various positive aspects and is an innovative process that has only been reported to a limited extent.
Economic Performance Evaluation of Flexible Centralised and Decentralised Blue Hydrogen Production Systems Design Under Uncertainty
Sep 2023
Publication
Blue hydrogen is viewed as an important energy vector in a decarbonised global economy but its large-scale and capital-intensive production displays economic performance vulnerabities in the face of increased market and regulatory uncertainty. This study analyses flexible (modular) blue hydrogen production plant designs and evaluates their effectiveness to enhance economic performance under uncertainty. The novelty of this work lies in the development of a comprehensive techno-economic evaluation framework that considers flexible centralised and decentralised blue hydrogen plant design alternatives in the presence of irreducible uncertainty whilst explicitly considering the time value of money economies of scale and learning effects. A case study of centralised and decentralised blue hydrogen production for the transport sector in the San Francisco area is developed to highlight the underlying value of flexibility. The proposed methodological framework considers various blue hydrogen plant designs (fixed phased and flexible) and compares them using relevant economic indicators (net present value (NPV) capex value-at-risk/gain etc.) through a detailed Monte Carlo simulation framework. Results indicate that flexible centralised hydrogen production yields greater economic value than alternative designs despite the associated cost-premium of modularity. It is also shown that the value of flexibility increases under greater uncertainty higher learning rates and weaker economies of scale. Moreover sensitivity analysis reveals that flexible design remains the preferred investment option over a wide range of market and regulatory conditions except for high initial hydrogen demand. Finally this study demonstrates that major regulatory and market uncertainties surrounding blue hydrogen production can be effectively managed through the application of flexible engineering system design that protects the investment from major downside risks whilst allowing access to favourable upside opportunities.
Development of Hydrogen Area Classification Data for Use in Village Trials
May 2023
Publication
The natural gas industry proposes carrying out trials on limited parts of the gas network using hydrogen as an alternative to natural gas as a fuel. Ahead of these trials it is important to establish whether the zones of negligible extent that are typically applied to natural gas systems could still be considered zones of negligible extent for hydrogen. The standard IGEM/UP/16 is commonly used by the natural gas industry to carry out area classification for low pressure gas systems for example as found in boiler houses. However IGEM/UP/16 is not applicable to hydrogen. Therefore IGEM commissioned HSE’s Science Division to develop some data that could be used to feed into an area classification assessment for the village trials.<br/>This report identifies two main elements of IGEM/UP/16 which may not apply to hydrogen and suggests values for hydrogen-specific alternatives. These are the ventilation rate requirements to allow a zone to be deemed of negligible extent and the definition of a confined space.
Operation Strategy for an Integrated Energy System Considering the Slow Dynamic Response Characteristics of Power-to-Gas Conversion
Jun 2024
Publication
Power-to-gas technology provides an emerging pathway for promoting green and lowcarbon transformation of energy systems. Through the processes of electrolyzing water and the methanation reaction it converts surplus renewable energy into hydrogen and natural gas offering an effective approach for large-scale integration of renewable energy sources. However the optimization of existing integrated energy systems has yet to finely model the operational characteristics of power-to-gas technology severely limiting the energy conversion efficiency of systems. To address this issue this paper proposes an integrated energy system operation strategy considering the slow dynamic response characteristics of power-to-gas. Firstly based on the technical features of power-to-gas an operational model for electrolyzing water to produce hydrogen is constructed considering the transition relationships among cold start-up hot start-up and production states of a methanation reaction thereby building a power-to-gas operation model considering slow dynamic response characteristics. This model finely reflects the impact of power-to-gas operational states on methanation facilitating accurate representation of the operational states of methanation. Then considering the energy conversion constraints and power balance of various coupled devices within integrated energy systems an optimization model for the operation of the integrated energy system is constructed with the total daily operation cost of the system as the optimization objective. Finally simulation comparisons are conducted to demonstrate the necessity of considering the slow dynamic response characteristics of power-to-gas technology for integrated energy system operation. The case study results indicate that the proposed power-to-gas operation model can accurately simulate the methanation process facilitating the rational conversion of surplus renewable energy into natural gas energy and avoiding misjudgments in system operation costs and energy utilization efficiency.
Potential Economic Benefits of Carbon Dioxide (CO2) Reduction Due to Renewable Energy and Electrolytic Hydrogen Fuel Deployment Under Current and Long Term Forecasting of the Social Carbon Cost (SCC)
May 2019
Publication
The 2016 Paris Agreement (UNFCCC Authors 2015) is the latest of initiative to create an international consensus on action to reduce GHG emissions. However the challenge of meeting its targets lies mainly in the intimate relationship between GHG emissions and energy production which in turn links to industry and economic growth. The Middle East and North African region (MENA) particularly those nations rich oil and gas (O&G) resources depend on these as a main income source. Persuading the region to cut down on O&G production or reduce its GHG emissions is hugely challenging as it is so vital to its economic strength. In this paper an alternative option is established by creating an economic link between GHG emissions measured as their CO2 equivalent (CO2e) and the earning of profits through the concept of Social Carbon Cost (SCC). The case study is a small coastal city in Libya where 6% of electricity is assumed to be generated from renewable sources. At times when renewable energy (RE) output exceeds the demand for power the surplus is used for powering the production of hydrogen by electrolysis thus storing the energy and creating an emission-free fuel. Two scenarios are tested based on short and long term SCCs. In the short term scenario the amount of fossil fuel energy saved matches the renewable energy produced which equates to the same amount of curtailed O&G production. The O&G-producing region can earn profits in two ways: (1) by cutting down CO2 emissions as a result of a reduction in O&G production and (2) by replacing an amount of fossil fuel with electrolytically-produced hydrogen which creates no CO2 emissions. In the short term scenario the value of SCC saved is nearly 39% and in the long term scenario this rose to 83%.
A Review of Hydrogen-based Hybrid Renewable Energy Systems: Simulation and Optimization with Artificial Intelligence
Nov 2021
Publication
With the massive use of traditional fossil fuels greenhouse gas emissions are increasing and environmental pollution is becoming an increasingly serious problem which led to an imminent energy transition. Therefore the development and application of renewable energy are particularly important. This paper reviews a wide range of issues associated with hybrid renewable energy systems (HRESs). The issues concerning system configurations energy storage options simulation and optimization with artificial intelligence are discussed in detail. Storage technology options are introduced for stand-alone (off-grid) and grid-connected (on-grid) HRESs. Different optimization methodologies including classical techniques intelligent techniques hybrid techniques and software tools for sizing system components are presented. Besides the artificial intelligence methods for optimizing the solar/wind HRESs are discussed in detail.
Multi-Objective Optimization for Solar-Hydrogen-Battery-Integrated Electric Vehicle Charging Stations with Energy Exchange
Oct 2023
Publication
The importance of electric vehicle charging stations (EVCS) is increasing as electric vehicles (EV) become more widely used. EVCS with multiple low-carbon energy sources can promote sustainable energy development. This paper presents an optimization methodology for direct energy exchange between multi-geographic dispersed EVCSs in London UK. The charging stations (CSs) incorporate solar panels hydrogen battery energy storage systems and grids to support their operations. EVs are used to allow the energy exchange of charging stations. The objective function of the solar-hydrogen-battery storage electric vehicle charging station (SHS-EVCS) includes the minimization of both capital and operation and maintenance (O&M) costs as well as the reduction in greenhouse gas emissions. The system constraints encompass the power output limits of individual components and the need to maintain a power balance between the SHS-EVCSs and the EV charging demand. To evaluate and compare the proposed SHS-EVCSs two multi-objective optimization algorithms namely the Non-dominated Sorting Genetic Algorithm (NSGA-II) and the Multi-objective Evolutionary Algorithm Based on Decomposition (MOEA/D) are employed. The findings indicate that NSGA-II outperforms MOEA/D in terms of achieving higher-quality solutions. During the optimization process various factors are considered including the sizing of solar panels and hydrogen storage tanks the capacity of electric vehicle chargers and the volume of energy exchanged between the two stations. The application of the optimized SHS-EVCSs results in substantial cost savings thereby emphasizing the practical benefits of the proposed approach.
Underground Hydrogen Storage: Integrated Surface Facilities and Fluid Flow Modelling for Depleted Gas Reservoirs
Aug 2023
Publication
We report a new techno-economic model to assess performance and capital costs for large-scale underground hydrogen storage in depleted gas reservoirs. A simulation toolbox is developed to model surface facilities and to simulate the hydrogen flow in geological formations in an integrated fashion.<br/>Integrated modelling revealed the following key insights: 1) A buffer system is highly desirable to absorb inherent variability in upstream hydrogen production; 2) hydrogen mixing with existing gases in the reservoir together with gravity segregation and diffusion results in a decline in hydrogen purity at the wellhead over time and can require increased purification; 3) the capital cost is dominated by the cost of cushion gas (hydrogen) and the compression system where about 9% of the total energy content of the hydrogen is consumed for compression. The scenarios modelled in our study result in a levelized cost of storage in Australia ranging from 2.3 to 4.29 A$/(kg).
Critical and Strategic Materials for Electrolysers, Fuel Cells, Metal Hydrides and Hydrogen Seperation Technologies
May 2024
Publication
This paper provides an in-depth examination of critical and strategic raw materials (CRMs) and their crucial role in the development of electrolyzer and fuel cell technologies within the hydrogen economy. It methodically analyses a range of electrolyzer technologies including alkaline proton-exchange membrane solid-oxide anion-exchange membrane and proton-conducting ceramic systems. Each technology is examined for its specific CRM dependencies operational characteristics and the challenges associated with CRM availability and sustainability. The study further extends to hydrogen storage and separation technologies focusing on the materials employed in high-pressure cylinders metal hydrides and hydrogen separation processes and their CRM implications. A key aspect of this paper is its exploration of the supply and demand dynamics of CRMs offering a comprehensive view that encompasses both the present sttate and future projections. The aim is to uncover potential supply risks understand strategies and identify potential bottlenecks for materials involved in electrolyzer and fuel cell technologies addressing both current needs and future demands as well as supply. This approach is essential for the strategic planning and sustainable development of the hydrogen sector emphasizing the importance of CRMs in achieving expanded electrolyzer capacity leading up to 2050.
The Future European Hydrogen Market: Market Design and Policy Recommendations to Support Market Development and Commodity Trading
May 2024
Publication
A key building block of the European Green Deal is the development of a hydrogen commodity market which requires a suitable hydrogen market design and the timely introduction of related policy measures. Using exploratory interviews with five expert groups we contribute to this novel research field by outlining the core market design criteria and proposing suitable regulations for the future European hydrogen market. We identify detailed recommendations along three core market design focus areas: Market development policy measures infrastructure regulations as well as hydrogen and certificate trading. Our findings provide an across-industry view of current policy-related key challenges in the hydrogen commodity market development and mitigation approaches. We therefore support policymakers within the EU in the ongoing detailing of their regulatory hydrogen and green energy packages. Further we promote hydrogen market development by assisting current and future industry players in finding a common understanding of the future hydrogen market design.
Hydrogenerally - Episode 9: Nuclear Hydrogen
Jan 2023
Publication
In this episode of the podcast Debra Jones Chemistry Knowledge Transfer Manager and Ray Chegwin Nuclear Knowledge Transfer Manager from Innovate UK KTN talk about nuclear uses for hydrogen with special guest Allan Simpson Technical Lead at the National Nuclear Laboratory.
The podcast can be found on their website.
The podcast can be found on their website.
Processes Supervision System for Green Hydrogen Production: Experimental Characterization and Data Acquisition of PEM Electrolyzer
May 2022
Publication
Green hydrogen is the term used to reflect the fact that hydrogen is generated from renewable energies. This process is commonly performed by means of water electrolysis decomposing water molecules into oxygen and hydrogen in a zero emissions process. Proton exchange membrane (PEM) electrolyzers are applied for such a purpose. These devices are complex systems with nonlinear behavior which impose the measurement and control of several magnitudes for an effective and safe operation. In this context the modern paradigm of Digital Twin (DT) is applied to represent and even predict the electrolyzer behavior under different operating conditions. To build this cyber replica a paramount previous stage consists of characterizing the device by means of the curves that relate current voltage and hydrogen flow. To this aim this paper presents a processes supervision system focused on the characterization of a experimental PEM electrolyzer. This device is integrated in a microgrid for production of green hydrogen using photovoltaic energy. Three main functions must be performed by the supervision system: measurement of the process magnitudes data acquisition and storage and real-time visualization. To accomplish these tasks firstly a set of sensors measure the process variables. In second place a programmable logic controller is responsible of acquiring the signals provided by the sensors. Finally LabVIEW implements the user interface as well as data storage functions. The process evolution is observed in real-time through the user interface composed by graphical charts and numeric indicators. The deployed process supervision system is reported together with experimental results to prove its suitability.
Optimal Design and Sizing of Hybrid Photovoltaic/Fuel Cell Electrical Power System
Aug 2023
Publication
Renewable energy solutions play a crucial role in addressing the growing energy demands while mitigating environmental concerns. This study examines the techno-economic viability and sensitivity of utilizing solar photovoltaic/polymer electrolyte membrane (PEM) fuel cells (FCs) to meet specific power demands in NEOM Saudi Arabia. The novelty of this study lies in its innovative approach to analyzing and optimizing PV/PEMFC systems aiming to highlight their economic feasibility and promote sustainable development in the region. The analysis focuses on determining the optimal size of the PV/PEMFC system based on two critical criteria: minimum cost of energy (COE) and minimum net present cost (NPC). The study considers PEMFCs with power ratings of 30 kW 40 kW and 50 kW along with four PV panel options: Jinko Solar Powerwave Tindo Karra and Trina Solar. The outcomes show that the 30 kW PEMFC and the 201 kW Trina Solar TSM-430NEG9R.28 are the most favorable choices for the case study. Under these optimal conditions the study reveals the lowest values for NPC at USD 703194 and COE at USD 0.498 per kilowatt-hour. The levelized cost of hydrogen falls within the range of USD 15.9 to 23.4 per kilogram. Furthermore replacing the 30 kW Trina solar panel with a 50 kW Tindo PV module results in a cost reduction of 32%. The findings emphasize the criticality of choosing optimal system configurations to attain favorable economic outcomes thereby facilitating the adoption and utilization of renewable energy sources in the region. In conclusion this study stands out for its pioneering and thorough analysis and optimization of PV/PEMFC systems providing valuable insights for sustainable energy planning in NEOM Saudi Arabia.
Techno-economic Analysis of Large-scale Green Hydrogen Production and Storage
Jun 2023
Publication
Producing clean energy and minimising energy waste are essential to achieve the United Nations sustainable development goals such as Sustainable Development Goal 7 and 13. This research analyses the techno-economic potential of waste heat recovery from multi-MW scale green hydrogen production. A 10 MW proton exchange membrane electrolysis process is modelled with a heat recovery system coupled with an organic Rankine cycle (ORC) to drive the mechanical compression of hydrogen. The technical results demonstrate that when implementing waste heat recovery coupled with an ORC the first-law efficiency of electrolyser increases from 71.4% to 98%. The ORC can generate sufficient power to drive the hydrogen's compression from the outlet pressure at the electrolyser 30 bar up to 200 bar. An economic analysis is conducted to calculate the levelised cost of hydrogen (LCOH) of system and assess the feasibility of implementing waste heat recovery coupled with ORC. The results reveal that electricity prices dominate the LCOH. When electricity prices are low (e.g. dedicated offshore wind electricity) the LCOH is higher when implementing heat recovery. The additional capital expenditure and operating expenditure associated with the ORC increases the LCOH and these additional costs outweigh the savings generated by not purchasing electricity for compression. On the other hand heat recovery and ORC become attractive and feasible when grid electricity prices are higher.
Industrial Development Status and Prospects of the Marine Fuel Cell: A Review
Jan 2023
Publication
In the context of the increasingly strict pollutant emission regulations and carbon emission reduction targets proposed by the International Maritime Organization the shipping industry is seeking new types of marine power plants with the advantages of high efficiency and low emissions. Among the possible alternatives the fuel cell is considered to be the most practical technology as it provides an efficient means to generate electricity with low pollutant emissions and carbon emissions. Very few comprehensive reviews focus on the maritime applications of the fuel cell. Thus news reports and literature on the maritime applications of the fuel cell in the past sixty years were collected and the industrial development status and prospects of the marine fuel cell were summarized as follows. Some countries in Europe North America and Asia have invested heavily in researching and developing the marine fuel cell and a series of research projects have achieved concrete results such as the industrialized marine fuel cell system or practical demonstration applications. At present the worldwide research of the marine fuel cell focuses more on the proton exchange membrane fuel cell (PEMFC). However the power demand of the marine fuel cell in the future will show steady growth and thus the solid oxide fuel cell (SOFC) with the advantages of higher power and fuel diversity will be the mainstream in the next research stage. Although some challenges exist the SOFC can certainly lead the upgrading and updating of the marine power system with the cooperative efforts of the whole world.
Refuelling Tests of a Hydrogen Tank for Heavy-duty Applications
Sep 2023
Publication
A transition towards zero-emission fuels is required in the mobility sector in order to reach the climate goals. Here (green) renewable hydrogen for use in fuel cells will play an important role especially for heavy duty applications such as trucks. However there are still challenges to overcome regarding efficient storage infrastructure integration and optimization of the refuelling process. A key aspect is to reduce the refuelling duration as much as possible while staying below the maximum allowed temperature of 85 C. Experimental tests for the refuelling of a 320 l type III tank were conducted at different operating conditions and the tank gas temperature measured at the front and back ends. The results indicate a strongly inhomogeneous temperature field where measuring and verifying the actual maximum temperatures proves difficult. Furthermore a simulation approach is provided to calculate the average tank gas temperature at the end of the refuelling process.
Low-carbon Development for the Iron and Steel Industry in China and the World: Status Quo, Future Vision, and Key Actions
Nov 2021
Publication
The low-carbon development of China’s iron and steel industry (ISI) is important but challenging work for the attainment of China’s carbon neutrality by 2060. However most previous studies related to the low-carbon development of China’s ISI are fragmented from different views such as production-side mitigation demand-side mitigation or mitigation technologies. Additionally there is still a lack of a comprehensive overview of the long-term pathway to the low-carbon development of China’s ISI. To respond to this gap and to contribute to better guide policymaking in China this paper conducted a timely and comprehensive review following the technology roadmap framework covering the status quo future vision and key actions of the low-carbon development of the world and China’s ISI. First this paper provides an overview of the technology roadmap of low-carbon development around the main steel production countries in the world. Second the potential for key decarbonization actions available for China’s ISI are evaluated in detail. Third policy and research recommendations are put forward for the future low-carbon development of China’s ISI. Through this comprehensive review four key actions can be applied to the low-carbon development of China’s ISI: improving energy efficiency shifting to Scrap/EAF route promoting material efficiency strategy and deploying radical innovation technologies.
Techno-economic Investigation of Hybrid Peaker Plant and Hydrogen Refuelling Station
Sep 2023
Publication
The power and transport sectors are responsible for significant emissions of greenhouse gases. Therefore it is imperative that substantial efforts are directed towards the decarbonisation of these industries. This study establishes a combined-solar-wind system's economic and technical practicality for producing hydrogen for an onsite hydrogen refuelling station (HRS) and electricity to meet peak demand. To minimise the levelised cost of electricity and maximise the system's reliability at different commercial locations in South Africa the dual-objective optimisation sizing is carried out using Mixed Integer Quadratic Constrained Programming (MICQP) model and was executed with an Advanced Multi-dimensional Modelling System (AIMMS) [61] [62]. The levelised costs of electricity and hydrogen at Johannesburg Pretoria and Cape Town for 2 MW grid export benchmark are 74.2 $/MWh/5.85 $/kg 76.3 $/MWh/5.97 $/kg and 50 $/MWh/4.45 $/kg respectively. The CO₂ equivalent emissions (tonnes) are 54000 55800 59000 and the corresponding carbon taxes ($) avoided for the locations are 432100 446200 and 472000 for Johannesburg Pretoria and Cape Town respectively. The results of the framework show that it can be adopted as a viable and fossil-free replacement for conventional peaking generators.
Design of Hydrogen Production Systems Powered by Solar and Wind Energy: An Insight into the Optimal Size Ratios
Jun 2024
Publication
Green hydrogen is expected to play a crucial role in the future energy landscape particularly in the pursuit of deep decarbonisation strategies within hard-to-abate sectors such as the chemical and steel industries and heavy-duty transport. However competitive production costs are vital to unlock the full potential of green hydrogen. In the case of green hydrogen produced via water electrolysis powered by fluctuating renewable energy sources the design of the plant plays a pivotal role in achieving market-competitive production costs. The present work investigates the optimal design of power-to-hydrogen systems powered by renewable sources (solar and wind energy). A detailed model of a power-to-hydrogen system is developed: an energy simulation framework coupled with an economic assessment provides the hydrogen production cost as a function of the component sizes. By spanning a wide range of size ratios namely the ratio between the size of the renewable generator and the size of the electrolyser the cost-optimal design point (minimum hydrogen production cost) is identified. This investigation is carried out for three plant configurations: solar-only wind-only and hybrid. The objective is to extend beyond the analysis of a specific case study and provide broadly applicable considerations for the optimal design of green hydrogen production systems. In particular the rationale behind the cost-optimal size ratio is unveiled and discussed through energy (utilisation factors) and economic (hydrogen production cost) indicators. A sensitivity analysis on investment costs for the power-to-hydrogen technologies is also conducted to explore various technological learning paths from today to 2050. The optimal size ratio is found to be a trade-off between the utilisation factors of the electrolyser and the renewable generator which exhibit opposite trends. Moreover the costs of the power-to-hydrogen technologies are a key factor in determining the optimal size ratio: depending on these costs the optimal solution tends to improve one of the two utilization factors at the expense of the other. Finally the optimal size ratio is foreseen to decrease in the upcoming years primarily due to the reduction in the investment cost of the electrolyser.
Design of a Hydrogen Aircraft for Zero Persistent Contrails
Jul 2023
Publication
Contrails are responsible for a significant proportion of aviation’s climate impact. This paper uses data from the European Centre for Medium-Range Weather Forecasts to identify the altitudes and latitudes where formed contrails will not persist. This reveals that long-lived contrails may be prevented by flying lower in equatorial regions and higher in non-equatorial regions. Subsequently it is found that the lighter fuel and reduced seating capacity of hydrogen-powered aircraft lead to a reduced aircraft weight which increases the optimal operating altitude by about 2 km. In non-equatorial regions this would lift the aircraft’s cruise point into the region where long-lived contrails do not persist unlocking hydrogen-powered low-contrails operation. The baseline aircraft considered is an A320 retrofitted with in-fuselage hydrogen tanks. The impacts of the higher-altitude cruise on fuel burn and the benefits unlocked by optimizing the wing geometry for this altitude are estimated using a drag model based on theory proposed by Cavcar Lock and Mason and verified against existing aircraft. The weight penalty associated with optimizing wing geometry for this altitude is estimated using Torenbeek’s correlation. It is found that thinner wings with higher aspect ratios are particularly suited to this high-altitude operation and are enabled by the relaxation of the requirement to store fuel in the wings. An example aircraft design for the non-equatorial region is provided which cruises at a 14 km altitude at Mach 0.75 with a less than 1% average probability of generating long-lived contrails when operating at latitudes more than 35◦ from the equator. Compared to the A320 this concept design is estimated to have a 20% greater cruise lift–drag ratio due to the 33% thinner wings with a 50% larger aspect ratio enabling just 5% more energy use per passenger-km despite fitting 40% fewer seats.
UK HSE Hydrogen for Heating Evidence Review Process
Sep 2023
Publication
As part of the UK Government’s Net Zero targets to tackle Climate Change the Health and Safety Executive (HSE) aims to reach an authoritative view on the safety of using 100% hydrogen for heating across the UK to feed into Government policy decisions by the mid-2020s. This paper describes the background and process of a programme of work led by HSE in support of the Department for Energy Security and Net Zero (formerly BEIS) that will inform strategic policy decisions by 2026. The strategic framework of HSE’s programme of work was defined between BEIS and HSE. HSE’s programme of work follows on from a previous project which engaged with HSE policy regulatory and scientific colleagues working with industry stakeholders identifying knowledge gaps for the safe distribution storage and use of hydrogen gas in domestic industrial and commercial premises. These knowledge gaps were subsequently used in discussions with stakeholders to prioritise research projects and evidence gathering exercises. To review this scientific evidence HSE developed a review framework and convened Evidence Review Groups (ERGs) to cover all evidence areas encompassing topics such as quantified risk assessment material compatibility and operational procedures. These ERGs include representation from relevant divisions across HSE (policy regulation and science). The paper explains the structure of HSE’s input into the hydrogen for heating programme the ERG process and timelines along with the proposed outputs. Additional activities have been undertaken by HSE within the programme to highlight specific issues in support of the review process which will also be discussed.
Exploring Hydrogen Embrittlement: Mechanisms, Consequences, and Advances in Metal Science
Jun 2024
Publication
Hydrogen embrittlement (HE) remains a pressing issue in materials science and engineering given its significant impact on the structural integrity of metals and alloys. This exhaustive review aims to thoroughly examine HE covering a range of aspects that collectively enhance our understanding of this intricate phenomenon. It proceeds to investigate the varied effects of hydrogen on metals illustrating its ability to profoundly alter mechanical properties thereby increasing vulnerability to fractures and failures. A crucial section of the review delves into how different metals and their alloys exhibit unique responses to hydrogen exposure shedding light on their distinct behaviors. This knowledge is essential for customizing materials to specific applications and ensuring structural dependability. Additionally the paper explores a diverse array of models and classifications of HE offering a structured framework for comprehending its complexities. These models play a crucial role in forecasting preventing and mitigating HE across various domains ranging from industrial settings to critical infrastructure.
Hydrogen–Natural Gas Mix—A Viable Perspective for Environment and Society
Aug 2023
Publication
The increase in demand and thus the need to lower its price has kept C-based fuels as the main source. In this context the use of oil and gas has led to increased climate change resulting in greenhouse gases. The high percentage of emissions over 40% is due to the production of electricity heat or/and energy transport. This is the main reason for global warming and the extreme and increasingly common climate change occurrences with all of nature being affected. Due to this reason in more and more countries there is an increased interest in renewable energies from sustainable sources with a particular emphasis on decarbonisation. One of the energies analysed for decarbonisation that will play a role in future energy systems is hydrogen. The development of hydrogen–natural gas mixtures is a major challenge in the field of energy and fuel technology. This article aims to highlight the major challenges associated with researching hydrogen–natural gas blends. Meeting this challenge requires a comprehensive research and development effort including exploring appropriate blending techniques optimising performance addressing infrastructure requirements and considering regulatory considerations. Overcoming this challenge will enable the full potential of hydrogen–natural gas blends to be realised as a clean and sustainable energy source. This will contribute to the global transition to a greener and more sustainable future. Several international European and Romanian studies projects and legislative problems are being analysed. The mix between H2 and natural gas decreases fugitive emissions. In contrast using hydrogen increases the risk of fire more than using natural gas because hydrogen is a light gas that easily escapes and ignites at almost any concentration in the air.
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.
The Hydrogen Economy can Reduce Costs of Climate Change Mitigation by up to 22%
May 2024
Publication
In response to the urgent need to mitigate climate change via net-zero targets many nations are renewing their interest in clean hydrogen as a net-zero energy carrier. Although clean hydrogen can be directly used in various sectors for deep decarbonization the relatively low energy density and high production costs have raised doubts as to whether clean hydrogen development is worthwhile. Here we improve on the GCAM model by including a more comprehensive and detailed representation of clean hydrogen production distribution and demand in all sectors of the global economy and simulate 25 scenarios to explore the costeffectiveness of integrating clean hydrogen into the global energy system. We show that due to costly technical obstacles clean hydrogen can only provide 3%–9% of the 2050 global final energy use. Nevertheless clean hydrogen deployment can reduce overall energy decarbonization costs by 15%–22% mainly via powering ‘‘hard-to-electrify’’ sectors that would otherwise face high decarbonization expenditures. Our work provides practical references for cost-effective clean hydrogen planning.
Sonochemical and Sonoelectrochemical Production of Hydrogen
Aug 2018
Publication
Reserves of fossil fuels such as coal oil and natural gas on earth are finite. The continuous use and burning of these fossil fuel resources in the industrial domestic and transport sectors has resulted in the extremely high emission of greenhouse gases GHGs (e.g. CO2) and solid particulates into the atmosphere. Therefore it is necessary to explore pollution free and more efficient energy sources in order to replace depleting fossil fuels. The use of hydrogen (H2) as an alternative fuel source is particularly attractive due to its very high specific energy compared to other conventional fuels and its zero GHG emission when used in a fuel cell. Hydrogen can be produced through various process technologies such as thermal electrolytic photolytic and biological processes. Thermal processes include gas reforming renewable liquid and biooil processing biomass and coal gasification; however these processes release a huge amount of greenhouse gases. Production of electrolytic hydrogen from water is an attractive method to produce clean hydrogen. It could even be a more promising technology when combining water electrolysis with power ultrasound to produce hydrogen efficiently where sonication enhances the electrolytic process in several ways such as enhanced mass transfer removal of hydrogen and oxygen (O2) gas bubbles and activation of the electrode surface. In this review production of hydrogen through sonochemical and sonoelectrochemical methods along with a brief description of current hydrogen production methods and power ultrasound are discussed.
Market-based Asset Valuation of Hydrogen Geological Storage
Jul 2023
Publication
Because of hydrogen's low energy density hydrogen storage is a critical component of the hydrogen economy particularly when large-scale and flexible hydrogen utilization is required. There is a sense of urgency to develop hydrogen geological storage projects to support large-scale yet flexible hydrogen utilization. This study aims to answer questions not yet resolved in the research literature discussing the valuation of hydrogen geological storage options for commercial development. This study establishes a net present value (NPV) evaluation framework for geological hydrogen storage that integrates the updated techno-economic analysis and market-based operations. The capital asset pricing model (CAPM) and the related finance theories are applied to determine the risk-adjusted discount rate in building the NPV evaluation framework. The NPV framework has been applied to two geological hydrogen storage projects a single-turn storage serving downstream transportation seasonal demand versus a multiturn storage as part of an integrated renewables-based hydrogen energy system providing peak electric load. From the NPV framework both projects have positive NPVs $46 560 632 and $12 457 546 respectively and International Rate of Return (IRR) values which are higher than the costs of capital. The NPV framework is also applied to the sensitivity analysis and shows that the hydrogen price spread between withdrawal and injection prices site development and well costs are the top three factors that impact both NPV and IRR the most for both projects. The established NPV framework can be used for project risk management by discovering the key cost drivers for the storage assets.
An Overview of Challenges for the Future of Hydrogen
Oct 2023
Publication
Hydrogen’s wide availability and versatile production methods establish it as a primary green energy source driving substantial interest among the public industry and governments due to its future fuel potential. Notable investment is directed toward hydrogen research and material innovation for transmission storage fuel cells and sensors. Ensuring safe and dependable hydrogen facilities is paramount given the challenges in accident control. Addressing material compatibility issues within hydrogen systems remains a critical focus. Challenges roadmaps and scenarios steer long-term planning and technology outlooks. Strategic visions align actions and policies encompassing societal and ecological dimensions. The confluence of hydrogen’s promise with material progress holds the prospect of reshaping our energy landscape sustainably. Forming collective future perspectives to foresee this emerging technology’s potential benefits is valuable. Our review article comprehensively explores the forthcoming challenges in hydrogen technology. We extensively examine the challenges and opportunities associated with hydrogen production incorporating CO2 capture technology. Furthermore the interaction of materials and composites with hydrogen particularly in the context of hydrogen transmission pipeline and infrastructure are discussed to understand the interplay between materials and hydrogen dynamics. Additionally the exploration extends to the embrittlement phenomena during storage and transmission coupled with a comprehensive examination of the advancements and hurdles intrinsic to hydrogen fuel cells. Finally our exploration encompasses addressing hydrogen safety from an industrial perspective. By illuminating these dimensions our article provides a panoramic view of the evolving hydrogen landscape.
Numerical Modelling of a Heavy-duty Diesel-hydrogen Dual-fuel Engine with Late High Pressure Hydrogen Direct Injection and Diesel Pilot
Sep 2023
Publication
Direct gaseous fuel injection in internal combustion engines is a potential strategy for improving in-cylinder combustion processes and performance while reducing emissions and increasing hydrogen energy share (HES). Through use of numerical modelling the current study explores combustion in a compression ignition engine utilising a late compression/early power stroke direct gaseous hydrogen injection ignited by a diesel pilot at up to 99% HES. The combustion process of hydrogen in this type of engine is mapped out and compared to that of the same engine using methane direct injection. Four distinct phases of combustion are found which differ from that of pure diesel operation. Interaction of the injected gas jet with the chamber walls is found to have a considerable impact on performance and emission characteristics and is a factor which needs to be explored in greater detail in future studies. Considerable performance increase and carbon-based emission reductions are identified at up to 99% HES at high load but low load performance greatly deteriorated when 95% HES was exceeded due to a much reduced diesel pilot struggling to ignite the main hydrogen injection.
Techno-economic Analysis to Identify the Optimal Conditions for Green Hydrogen Production
Jun 2023
Publication
The intermittency of renewable energy sources necessitates energy storage to meet the full demand and balancing requirements of the grid. Green hydrogen (H2) is a chemical energy carrier that can be used in a flexible manner and store large amounts of energy for long periods of time. This techno-economic analysis investigates H2 production from wind using commercially available desalination and electrolysis units. Proton exchange membrane and alkaline electrolyser units are utilised and compared. The intermittency of wind is examined with comparison against grid-bought electricity. A model is developed to determine the selling price required to ensure profitability over a 10-year period. Firstly where H2 is produced using energy from the grid with electricity purchased when below a specified price point or between specified hours. In the second scenario a wind turbine is owned by the user and the electricity price is not considered while the turbine capital expenditure is. The price of H2 production from wind is found to be comparable with natural gas derived H2 at a larger scale with a minimum selling price calculated to be 4.85 £/kg at a setpoint of 500 kg of H2/hr. At a setpoint of 50 kg of H2/hr this is significantly higher at 12.10 £/kg. In both cases the alkaline electrolyser produced cheaper H2. This study demonstrates an economy of scale with H2 prices decreasing with increased scale. H2 prices are also closely linked to the capital expenditure with the equipment size space and safety identified as limiting factors.
Investigation of Hybrid Power-to-hydrogen/Nautral Gas and Hydrogen-to-X System in Cameroon
May 2024
Publication
In Sub-Saharan Africa (SSA) the capacity to generate energy faces significant hurdles. Despite efforts to integrate renewable energy sources and natural gas power plants into the energy portfolio the desired reduction in environmental impact and alleviation of energy poverty remain elusive. Hence exploring a spectrum of hybrid technologies encompassing storage and hydrogen-based solutions is imperative to optimize energy production while mitigating harmful emissions. To exemplify this necessity the 216 MW Kribi gas power plant in Cameroon is the case study. The primary aim is to investigate cutting-edge emissions and energy schemes within the SSA. This paper assessed the minimum complaint load technique and four power-to-fuel options from technical financial and environmental perspectives to assess the viability of a natural gas fuel system powered with hydrogen in a hybrid mode. The system generates hydrogen by using water electrolysis with photovoltaic electricity and gas power plant. This research also assesses process efficiency storage capacity annual costs carbon avoided costs and production prices for various fuels. Results showed that the LCOE from a photovoltaic solar plant is 0.19$/kWh with the Power-to-Hydrogen process (76.2% efficiency) being the most efficient followed by the ammonia and urea processes. The study gives a detailed examination of the hybrid hydrogen natural gas fuel system. According to the annual cost breakdown the primary costs are associated with the acquisition of electrical energy and electrolyser CAPEX and OPEX which account for 95% of total costs. Urea is the cheapest mass fuel. However it costs more in terms of energy. Hydrogen is the most cost-effective source of energy. In terms of energy storage and energy density by volume the methane resulted as the most suitable solution while the ammonia resulted as the best H2 storage medium in terms of kg of H2 per m3 of storage (108 kgH2/m3 ). By substituting the fuel system with 15% H2 the environmental effects are reduced by 1622 tons per year while carbon capture technology gathered 16664 tons of CO2 for methanation and urea operations yielding a total carbon averted cost of 21 $/ton.
3D Modeling of the Different Boiling Regimes During Spill and Spreading of Liquid Hydrogen
Nov 2012
Publication
In a future energy generation market the storage of energy is going to become increasingly important. Besides classic ways of storage like pumped storage hydro power stations etc the production of hydrogen will play an important role as an energy storage system. Hydrogen may be stored as a liquefied gas (LH2) on a long term base as well as for short term supply of fuel stations to ensure a so called “green” mobility. The handling with LH2 has been subject to several recent safety studies. In this context reliable simulation tools are necessary to predict the spill and spreading of LH2 during an accidental release. This paper deals with the different boiling regimes: film boiling transition boiling and nucleation boiling after a release and their modeling by means of an inhouse-code for wall evaporation which is implemented in the commercial CFD code ANSYS CFX. The paper will describe the model its implementation and validation against experimental data such as the HSL LH2 spill experiments.
Carbon-negative Hydrogen Production (HyBECCS): An Exemplary Techno-economic and Environmental Assessment
Sep 2023
Publication
An exemplary techno-economic and environmental assessment of carbon-negative hydrogen (H2) production is carried out in this work. It is based on the so-called “dark photosynthesis” with carbon dioxide (CO2) capture and geological storage. As a special feature of the assessment the economic consequences due to the impact on the global climate are taken into account. The results indicate that the example project would be capable of generating negative GHG emissions under the assumptions made. The amount is estimated to be 17.72 kgCO2 to be removed from the atmosphere per kilogram of H2 produced. The levelized costs of carbon-negative hydrogen are obtained considering the economic impact of greenhouse gas emissions and removals. They are estimated to be 0.013 EUR/kWhH2. Compared to grey hydrogen from natural gas (0.12 EUR/kWhH2) and green hydrogen from electrolysis using renewable electricity (0.18 EUR/kWhH2) this shows a potential environmental-economic advantage of the considered example. Even without internalization of GHG impacts an economic advantage of the project (0.12 EUR/kWhH2) over green hydrogen (0.17 EUR/kWhH2) is indicated. Compared to other NETs the GHG removal efficiency is at the lower end of both BECCS and DACCS approaches.
Hydrogen as a Deep Sea Shipping Fuel: Modelling the Volume Requirements
May 2024
Publication
Recent targets have increased pressure for the maritime sector to accelerate the uptake of clean fuels. A potential future fuel for shipping is hydrogen however there is a common perception that the volume requirements for this fuel are too large for deep sea shipping. This study has developed a range of techniques to accurately simulate the fuel requirements of hydrogen for a case study vessel. Hydrogen can use fuel cells which achieve higher efficiencies than combustion methods but may require a battery hybrid system to meet changes in demand. A series of novel models for different fuel cell types and other technologies have been developed. The models have been used to run dynamic simulations for different energy system setups. Simulations tested against power profiles from real-world shipping data to establish the minimum viable setup capable of meeting all the power demand for the case study vessel to a higher degree of accuracy than previously achieved. Results showed that the minimum viable setup for hydrogen was with liquid storage a 105.6 MW PEM fuel cell stack and 6.9 MWh of batteries resulting in a total system size of 8934 m3 . Volume requirement results could then be compared to other concepts such as systems using ammonia and methanol 8970 m3 and 6033 m3 respectively.
Techno-economic Analysis and Predictive Operation of a Power-to-hydrogen for Renewable Microgrids
Oct 2023
Publication
To enhance renewable energy (RE) generation and maintain power balance energy storage systems are of utmost importance. This research introduces a cutting-edge Power-to-Hydrogen (PtH) framework that harnesses hydrogen as a clean and versatile energy storage medium. The primary focus of this study lies in optimizing power flow within a microgrid (G) equipped with RE and energy storage systems considering various factors such as RE generation power demand battery charge cycles and operational costs. To achieve the optimal balance between power generation and consumption a sophisticated mathematical solution is devised. This solution governs the charging and discharging patterns for both battery and electrolyzer ensuring a harmonious power equilibrium. The use of short-term forecasting further refines the optimization process adapting the parameters based on anticipated RE sources and load requirements. To fine-tune the power management solution for day-to-day operations an artificial neural fuzzy inference system (ANFIS)-based shortterm prediction model is employed. The predictive analysis provides confidence intervals for crucial aspects including power generation demand battery charging cycles and hydrogen generation. This facilitates precise cost estimation across various hydrogen and heat price ranges. the proposed PtH optimization framework offers an efficient approach to balance power generation and consumption in Gs driven by RE sources and energy storage. To validate the proposed approach numerical simulations are performed based on data from wind and solar farms load requirements and cost of energy. The results show that the proposed energy management strategy significantly reduces operational costs and optimizes PtH generation while maintaining power balance within the microgrid (G). The predictive approach helps fine-tune the optimization process improving efficiency and cost-effectiveness. The research convincingly demonstrate the economic advantages of adopting hydrogen as an energy storage medium paving the way for a cleaner and more sustainable energy future.
The Role of Hydrogen for a Greenhouse Gas-neutral Germany by 2045
May 2023
Publication
This paper aims to provide a holistic analysis of the role of hydrogen for achieving greenhouse gas neutrality in Germany. For that purpose we apply an integrated energy system model which includes all demand sectors of the German energy system and optimizes the transformation pathway from today's energy system to a future cost-optimal energy system. We show that 412 TWh of hydrogen are needed in the year 2045 mostly in the industry and transport sector. Particularly the use of about 267 TWh of hydrogen in industry is essential as there are no cost-effective alternatives for the required emission reduction in the chemical industry or in steel production. Furthermore we illustrate that the German hydrogen supply in the year 2045 requires both an expansion of domestic electrolyzer capacity to 71 GWH2 and hydrogen imports from other European countries and Northern Africa of about 196 TWh. Moreover flexible operation of electrolyzers is cost-optimal and crucial for balancing the intermittent nature of volatile renewable energy sources. Additionally a conducted sensitivity analysis shows that full domestic hydrogen supply in Germany is possible but requires an electrolyzer capacity of 111 GWH2.
Development of a Fuel Cell-based System for Refrigerated Transport
Nov 2012
Publication
Benchmark refrigerated systems in the road transportation sector are powered by diesel having operation costs of up to 6000 €/y. This paper presents the development of an alternative refrigeration system based on fuel cells with higher efficiency reduced costs and independent of diesel price fluctuations. Energy load profiles have been analyzed and the fuel cell stack and auxiliaries are being modeled in order to dimension and design a balance of plant and control algorithms that ensure a safe and easy utilization. Additionally a prototype shall be tested under different load profiles to validate the control strategies and to characterize the performance of the system.
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.
Game-Theory-Based Design and Analysis of a Peer-to-Peer Energy Exchange System between Multi-Solar-Hydrogen-Battery Storage Electric Vehicle Charging Stations
Jun 2024
Publication
As subsidies for renewable energy are progressively reduced worldwide electric vehicle charging stations (EVCSs) powered by renewable energy must adopt market-driven approaches to stay competitive. The unpredictable nature of renewable energy production poses major challenges for strategic planning. To tackle the uncertainties stemming from forecast inaccuracies of renewable energy this study introduces a peer-to-peer (P2P) energy trading strategy based on game theory for solar-hydrogen-battery storage electric vehicle charging stations (SHS-EVCSs). Firstly the incorporation of prediction errors in renewable energy forecasts within four SHS-EVCSs enhances the resilience and efficiency of energy management. Secondly employing game theory’s optimization principles this work presents a day-ahead P2P interactive energy trading model specifically designed for mitigating the variability issues associated with renewable energy sources. Thirdly the model is converted into a mixed integer linear programming (MILP) problem through dual theory allowing for resolution via CPLEX optimization techniques. Case study results demonstrate that the method not only increases SHS-EVCS revenue by up to 24.6% through P2P transactions but also helps manage operational and maintenance expenses contributing to the growth of the renewable energy sector.
Gas Turbine Combustion Technologies for Hydrogen Blends
Sep 2023
Publication
The article reviews gas turbine combustion technologies focusing on their current ability to operate with hydrogen enriched natural gas up to 100% H2. The aim is to provide a picture of the most promising fuel-flexible and clean combustion technologies the object of current research and development. The use of hydrogen in the gas turbine power generation sector is initially motivated highlighting both its decarbonisation and electric grid stability objectives; moreover the state-of-the-art of hydrogen-blend gas turbines and their 2024 and 2030 targets are reported in terms of some key performance indicators. Then the changes in combustion characteristics due to the hydrogen enrichment of natural gas blends are briefly described from their enhanced reactivity to their pollutant emissions. Finally gas turbine combustion strategies both already commercially available (mostly based on aerodynamic flame stabilisation self-ignition and staging) or still under development (like the micro-mixing and the exhaust gas recirculation concepts) are described.
Exploring Dilution Potential for Full Load Operation of Medium Duty Hydrogen Engine for the Transport Sector
Jul 2023
Publication
The current political scenario and the concerns for global warming have pushed very harsh regulations on conventional propulsion systems based on the use of fossil fuels. New technologies are being promoted but their current technological status needs further research and development for them to become a competitive substitute for the ever-present internal combustion engine. Hydrogen-fueled internal combustion engines have demonstrated the potential of being a fast way to reach full decarbonization of the transport sector but they still have to face some limitations in terms of the operating range of the engine. For this reason the present work evaluates the potential of reaching full load operation on a conventional diesel engine assuming the minimum modifications required to make it work under H2 combustion. This study shows the methodology through which the combustion model was developed and then used to evaluate a multi-cylinder engine representative of the medium to high duty transport sector. The evaluation included different strategies of dilution to control the combustion performance and the results show that the utilization of EGR brings different benefits to engine operation in terms of efficiency improvement and emissions reduction. Nonetheless the requisites defined for the needed turbocharging system are harsher than expected and result in a potential non-conventional technical solution.
Performance Analysis of a Diabatic Compressed Air Energy Storage System Fueled with Green Hydrogen
Oct 2023
Publication
The integration of an increasing share of Renewable Energy Sources (RES) requires the availability of suitable energy storage systems to improve the grid flexibility and Compressed Air Energy Storage (CAES) systems could be a promising option. In this study a CO2 -free Diabatic CAES system is proposed and analyzed. The plant configuration is derived from a down-scaled version of the McIntosh Diabatic CAES plant where the natural gas is replaced with green hydrogen produced on site by a Proton Exchange Membrane electrolyzer powered by a photovoltaic power plant. In this study the components of the hydrogen production system are sized to maximize the self-consumption share of PV energy generation and the effect of the design parameters on the H2 -CAES plant performance are analyzed on a yearly basis. Moreover a comparison between the use of natural gas and hydrogen in terms of energy consumption and CO2 emissions is discussed. The results show that the proposed hydrogen fueled CAES can effectively match the generation profile and the yearly production of the natural gas fueled plant by using all the PV energy production while producing zero CO2 emissions.
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.
Synergistic Integration of Hydrogen Energy Economy with UK’s Sustainable Development Goals: A Holistic Approach to Enhancing Safety and Risk Mitigation
Oct 2023
Publication
Hydrogen is gaining prominence as a sustainable energy source in the UK aligning with the country’s commitment to advancing sustainable development across diverse sectors. However a rigorous examination of the interplay between the hydrogen economy and the Sustainable Development Goals (SDGs) is imperative. This study addresses this imperative by comprehensively assessing the risks associated with hydrogen production storage transportation and utilization. The overarching aim is to establish a robust framework that ensures the secure deployment and operation of hydrogen-based technologies within the UK’s sustainable development trajectory. Considering the unique characteristics of the UK’s energy landscape infrastructure and policy framework this paper presents practical and viable recommendations to facilitate the safe and effective integration of hydrogen energy into the UK’s SDGs. To facilitate sophisticated decision making it proposes using an advanced Decision-Making Trial and Evaluation Laboratory (DEMATEL) tool incorporating regret theory and a 2-tuple spherical linguistic environment. This tool enables a nuanced decision-making process yielding actionable insights. The analysis reveals that Incident Reporting and Learning Robust Regulatory Framework Safety Standards and Codes are pivotal safety factors. At the same time Clean Energy Access Climate Action and Industry Innovation and Infrastructure are identified as the most influential SDGs. This information provides valuable guidance for policymakers industry stakeholders and regulators. It empowers them to make well-informed strategic decisions and prioritize actions that bolster safety and sustainable development as the UK transitions towards a hydrogen-based energy system. Moreover the findings underscore the varying degrees of prominence among different SDGs. Notably SDG 13 (Climate Action) exhibits relatively lower overall distinction at 0.0066 and a Relation value of 0.0512 albeit with a substantial impact. In contrast SDG 7 (Clean Energy Access) and SDG 9 (Industry Innovation and Infrastructure) demonstrate moderate prominence levels (0.0559 and 0.0498 respectively) each with its unique influence emphasizing their critical roles in the UK’s pursuit of a sustainable hydrogen-based energy future.
Hydrogen Combustion: Features and Barriers to Its Exploitation in the Energy Transition
Oct 2023
Publication
The aim of this article is to review hydrogen combustion applications within the energy transition framework. Hydrogen blends are also included from the well-known hydrogen enriched natural gas (HENG) to the hydrogen and ammonia blends whose chemical kinetics is still not clearly defined. Hydrogen and hydrogen blends combustion characteristics will be firstly summarized in terms of standard properties like the laminar flame speed and the adiabatic flame temperature but also evidencing the critical role of hydrogen preferential diffusion in burning rate enhancement and the drastic reduction in radiative emission with respect to natural gas flames. Then combustion applications in both thermo-electric power generation (based on internal combustion engines i.e. gas turbines and piston engines) and hard-to-abate industry (requiring high-temperature kilns and furnaces) sectors will be considered highlighting the main issues due to hydrogen addition related to safety pollutant emissions and potentially negative effects on industrial products (e.g. glass cement and ceramic).
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
Elevating the Prospects of Green Hydrogen (H2) Production Through Solar-powered Water Splitting Devices: A Systematic Review
May 2024
Publication
As the commercialisation of two contrasting solar-powered water splitting devices with lower TRLs of proton exchange membrane (PEM) electrolyser systems and photoelectrochemical (PEC) systems gains momentum the path towards a sustainable H2 economy is taking shape. Ongoing pilot projects and demonstration plants are proving the feasibility and potential of these technologies in real-world applications. However to ensure their success we must confront the critical challenges of cost reduction and efficiency enhancement making green H2 economically competitive with traditional production methods. To achieve this a collaborative effort among academia industry and policymakers is paramount. This comprehensive review begins by examining traditional water electrolysis methods focusing on the production of green H2 through electrochemical splitting. It delves into crucial components and advancements in the PEM systems addressing challenges related to catalysts membranes gas diffusion layers and bipolar plates. The review also explores solar-driven PEC water splitting emphasizing the significance of efficient photoelectrodes and reactor design. Additionally it discusses the integration of photovoltaic cells with electrochemical or PEC systems for higher H2 yield. Commercialisation is underway and this endeavour necessitates a collaborative approach with active involvement from academia industry and policymakers. This collective effort not only propels us towards greener and more sustainable energy solutions but also represents a transformative step in the global journey towards a sustainable and environmentally conscious economy.
LCA of a Proton Exchange Membrane Fuel Cell Electric Vehicle Considering Different Power System Architectures
Sep 2023
Publication
Fuel cell electric vehicles are a promising solution for reducing the environmental impacts of the automotive sector; however there are still some key points to address in finding the most efficient and less impactful implementation of this technology. In this work three electrical architectures of fuel cell electric vehicles were modeled and compared in terms of the environmental impacts of their manufacturing and use phases. The three architectures differ in terms of the number and position of the DC/DC converters connecting the battery and the fuel cell to the electric motor. The life cycle assessment methodology was employed to compute and compare the impacts of the three vehicles. A model of the production of the main components of vehicles and fuel cell stacks as well as of the production of hydrogen fuel was constructed and the impacts were calculated using the program SimaPro. Eleven impact categories were considered when adopting the ReCiPe 2016 midpoint method and the EF (adapted) method was exploited for a final comparison. The results highlighted the importance of the converters and their influence on fuel consumption which was identified as the main factor in the comparison of the environmental impacts of the vehicle.
Review of Sampling and Analysis of Particulate Matter in Hydrogen Fuel
Sep 2023
Publication
This review presents state-of-the-art for representative sampling of hydrogen from hydrogen refueling stations. Documented sampling strategies are presented as well as examples of commercially available equipment for sampling at the hydrogen refueling nozzle. Filter media used for sampling is listed and the performance of some of the filters evaluated. It was found that the filtration efficiency of 0.2 and 5 mm filters were not significantly different when exposed to 200 and 300 nm particles. Several procedures for gravimetric analysis are presented and some of the challenges are identified to be filter degradation pinhole formation and conditioning of the filter prior to measurement. Lack of standardization of procedures was identified as a limitation for result comparison. Finally the review summarizes results including particulate concentration in hydrogen fuel quality data published. It was found that less than 10% of the samples were in violation with the tolerance limit.
Policy Design for Diffusing Hydrogen Economy and Its Impact on the Japanese Economy for Carbon Neutrality by 2050: Analysis Using the E3ME-FTT Model
Nov 2023
Publication
To achieve carbon neutrality in Japan by 2050 renewable energy needs to be used as the main energy source. Based on the constraints of various renewable energies the importance of hydrogen cannot be ignored. This study aimed to investigate the diffusion of hydrogen demand technologies in various sectors and used projections and assumptions to investigate the hydrogen supply side. By performing simulations with the E3ME-FTT model and comparing various policy scenarios with the reference scenario the economic and environmental impacts of the policy scenarios for hydrogen diffusion were analyzed. Moreover the impact of realizing carbon neutrality by 2050 on the Japanese economy was evaluated. Our results revealed that large-scale decarbonization via hydrogen diffusion is possible (90% decrease of CO2 emissions in 2050 compared to the reference) without the loss of economic activity. Additionally investments in new hydrogen-based and other low-carbon technologies in the power sector freight road transport and iron and steel industry can improve the gross domestic product (1.6% increase in 2050 compared to the reference) as they invoke economic activity and require additional employment (0.6% increase in 2050 compared to the reference). Most of the employment gains are related to decarbonizing the power sector and scaling up the hydrogen supply sector while a lot of job losses can be expected in the mining and fossil fuel industries.
Optimal Configuration and Scheduling Model of a Multi-Park Integrated Energy System Based on Sustainable Development
Mar 2023
Publication
To maximize the utilization of renewable energy (RE) as much as possible in cold areas while reducing traditional energy use and carbon dioxide emissions a three-layer configuration optimization and scheduling model considering a multi-park integrated energy system (MPIES) a shared energy storage power station (SESPS) and a hydrogen refueling station (HRS) cooperation based on the Wasserstein generative adversarial networks the simultaneous backward reduction technique and the Quantity-Contour (WGAN-SBR_QC) method is proposed. Firstly the WGAN-SBR_QC method is used to generate typical scenarios of RE output. Secondly a three-layer configuration and schedule optimization model is constructed using MPIES SESPS and HRS. Finally the model’s validity is investigated by selecting a multi-park in Eastern Mongolia. The results show that: (1) the typical scenario of RE output improved the overall robustness of the system. (2) The profits of the MPIES and HRS increased by 1.84% and 52.68% respectively and the SESPS profit increased considerably. (3) The proposed approach increased RE utilization to 99.47% while reducing carbon emissions by 32.67%. Thus this model is a reference for complex energy system configuration and scheduling as well as a means of encouraging RE use.
Calibration Facilities and Test Results for Gas Network Hydrogen and Hydrogen Enriched Natural Gas Flow Meters
Jul 2025
Publication
The transition to a decarbonized gas network requires the adaptation of existing infrastructure to accommodate hydrogen and hydrogen-enriched natural gas. This study presents the development of calibration facilities at NEL VSL and DNV for evaluating the performance of flow meters under hydrogen conditions. Nine flow meters were tested covering applications from household consumption to distribution networks. Results demonstrated that rotary displacement meters and diaphragm meters are typically suitable for hydrogen and hydrogenenriched natural gas domestic and commercial consumers use. Tests results for an orifice meter confirmed that a discharge coefficient calibrated with nitrogen can be reliably used for hydrogen by matching Reynolds numbers. Thermal mass flow meters when not configured for the specific test gas exhibited significant errors emphasizing the necessity of gas-specific calibration and configuration. Turbine meters showed predictable error trends influenced by Reynolds number and bearing friction with natural gas calibration providing reliable hydrogen and hydrogen-enriched natural gas performance in the Reynolds domain. It was confirmed that ultrasonic meter performance varies by manufacturers with some meter models requiring a correction for gas composition bias when used in hydrogen enriched natural gas applications. These findings provide critical experimental data to guide future hydrogen metering standards and infrastructure adaptations supporting the European Union’s goal of integrating hydrogen into the gas network.
Energy Performance Assessment of a Solar-driven Thermochemical Cycle Device for Green Hydrogen Production
Sep 2023
Publication
This paper presents a novel dynamic simulation model for assessing the energy performance of solar-driven systems employed in green hydrogen production. The system consists of a parabolic dish collector that focuses solar radiation on two cerium-based thermochemical reactors. The model is based on a transient finitedifference method to simulate the thermal behaviour of the system and it integrates a theoretical analysis of materials and operating principles. Different empirical data were considered for experimentally validating it: a good agreement between experimental and simulated results was obtained for the temperatures calculated inside the thermochemical reactor (R2 = 0.99 MAPE = 6.3%) and the hourly flow rates of hydrogen oxygen and carbon monoxide (R2 = 0.96 MAPE = 10%) inside the thermochemical reactor. The model was implemented in a MatLab tool for the system dynamic analysis under different boundary conditions. Subsequently to explore the capability of this approach the developed tool was used for analysing the examined device operating in twelve different weather zones. The obtained results comprise heat maps of specific crucial instants and hourly dynamic trends showing redox reaction cycles occurring into the thermochemical reactors. The yearly hydrogen production ranges from 1.19 m3 /y to 1.64 m3 /y according to the hourly incident solar radiations outdoor air temperatures and wind speeds. New graphic tools for rapid feasibility studies are presented. The developed tools and the obtained results can be useful to the basic design of this technology and for the multi-objective optimization of its layout and main design/operating parameters.
Systems-Based Safety Analysis for Hydrogen-Driven Autonomous Ships
Jun 2024
Publication
In the maritime domain hydrogen fuel cell propulsion and autonomous vessels are two important issues that are yet to be implemented together because of a few challenges. It is obvious that there are several individual safety studies on Maritime Autonomous Surface Ships and hydrogen storage as well as fuel cells based on various risk assessment tools but the combined safety studies that include hydrogen fuel cells on autonomous vessels with recent risk analysis methods are extremely limited. This research chooses the “System-Theoretic Process Analysis” (STPA) method which is a recent method for potential risk identification and mitigation. Both hydrogen and autonomous vessels are analyzed and assessed together with the STPA method. Results are not speculative but rather flexible compared to conventional systems. The study finds a total of 44 unsafe control actions (UCAs) evolved from human and central control unit controllers through STPA. Further the loss scenarios (LS) are identified that lead to those UCAs so that loss scenarios can be assessed and UCAs can be mitigated for safe operation. The objective of this study is to ensure adequate safety for hydrogen fuel cell propulsion on autonomous vessels.
Topology and Control of Fuel Cell Generation Converters
Jun 2023
Publication
Fuel cell power generation is one of the important ways of utilizing hydrogen energy which has good prospects for development. However fuel cell volt-ampere characteristics are nonlinear the output voltage is low and the fluctuation range is large and a power electronic converter matching its characteristics is required to achieve efficient and stable work. Based on the analysis of the fuel cell’s characteristic mechanism maximum power point tracking algorithm fuel cell converter characteristics application and converter control strategy the paper summarizes the general principles of the topology of fuel cell converters. In addition based on the development status of new energy hydrogen energy is organically combined with other new energy sources and the concept of 100% absorption system of new energy with green hydrogen as the main body is proposed to provide a reference for the development of hydrogen energy.
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 Industrial Decarbonization: A MILP Optimization Model for Low-carbon Hydrogen Supply Chains
Jun 2024
Publication
This study develops a an optimization model focused on the layout and dispatch of a low-carbon hydrogen supply chain. The objective is to identify the lowest Levelized Cost of Hydrogen for a given demand. The model considers various elements including electricity supply from the local grid and renewable sources (photovoltaic and wind) alongside hydrogen production compression storage and transportation to end users. Applied to an industrial case study in Sweden the findings indicate that the major cost components are linked to electricity generation and investment in electrolyzers with the LCOH reaching 5.2 EUR/kgH2 under typical demand conditions. Under scenarios with higher peak demands and greater demand volatility the LCOH increases to 6.8 EUR/kgH2 due to the need for additional renewable energy capacity. These results highlight the critical impact of electricity availability and demand fluctuations on the LCOH emphasizing the complex interdependencies within the hydrogen supply chain. This study provides valuable insights into the feasibility and cost-effectiveness of adopting hydrogen as an energy carrier for renewable electricity in the context of decarbonizing industrial processes in the energy system.
Full Load Optimization of a Hydrogen Fuelled Industrial Engine
Jun 2024
Publication
There are a large number of applications in which hydrogen internal combustion engines represent a sensible alternative to battery electric propulsion systems and to fuel cell electric propulsion systems. The main advantages of combustion engines are their high degree of robustness and low manufacturing costs. No critical raw materials are required for production and there are highly developed production plants worldwide. A CO2-free operation is possible when using hydrogen as a fuel. The formation of nitrogen oxides during hydrogen combustion in the engine can be effectively mitigated by a lean-burn combustion process. However achieving low NOx raw emissions conflicts with achieving high power yields. In this work a series industrial diesel engine was converted for hydrogen operation and comprehensive engine tests were carried out. Various measures to improve the trade-off between NOx emissions and performance were investigated and evaluated. The rated power output and the maximum torque of the series diesel engine could be exceeded while maintaining an indicated specific NOx emission of 1 g/kWh along the entire full load curve. In the low-end-torque range however the gap to the full load curve of the series diesel engine could not be fully closed with the hardware used.
Price Promises, Trust Deficits and Energy Justice: Public Perceptions of Hydrogen Homes
Oct 2023
Publication
In an era characterised by political instability economic uncertainty and mounting environmental pressures hydrogen fuel is being positioned as a critical piece of the global energy security and clean energy agenda. The policy push is noteworthy in the United Kingdom where the government is targeting industrial decarbonisation via hydrogen while exploring a potential role for hydrogen-fuelled home appliances. Despite the imperative to secure social acceptance for accelerating the diffusion of low-carbon energy technologies public perceptions of hydrogen homes remain largely underexplored by the researcher community. In response this analysis draws on extensive focus group data to understand the multi-dimensional nature of social acceptance in the context of the domestic hydrogen transition. Through an integrated mixed-methods multigroup analysis the study demonstrates that socio-political and market acceptance are strongly interlinked owing to a trust deficit in the government and energy industry coupled to underlying dissatisfaction with energy markets. At the community level hydrogen homes are perceived as a potentially positive mechanism for industrial regeneration and local economic development. Households consider short-term disruptive impacts to be tolerable provided temporary disconnection from the gas grid does not exceed three days. However to strengthen social acceptance clearer communication is needed regarding the spatial dynamics and equity implications of the transition. The analysis concludes that existing trust deficits will need to be overcome which entails fulfilling not only a ‘price promise’ on the cost of hydrogen appliances but also enacting a ‘price pledge’ on energy bills. These deliverables are fundamental to securing social acceptance for hydrogen homes.
Designing Off-grid Green Hydrogen Plants Using Dynamic Polymer Electrolyte Membrane Electrolyzers to Minimize the Hydrogen Production Cost
Oct 2023
Publication
Hydrogen produced from electrolysis is an attractive carbon-free fuel and feedstock but potential benefits depend on the carbon intensity of electricity production. This study uses technoeconomic modeling to analyze the benefits of producing zero-carbon hydrogen through dynamically operated polymer electrolyte membrane electrolyzers connected to photovoltaic and wind variable renewable energy (VRE) sources. Dynamic operation is considered for current densities between 0 and 6 A cm2 and compared to a constant current density of 2 A cm2 for different combinations of VRE to electrolysis (VRE:E) capacity ratios and compositions of photovoltaic and wind energy in four locations across the United States. For optimal VRE:E and wind:photovoltaic capacity ratios dynamic operation is found to reduce the levelized cost of hydrogen by 5%–9% while increasing hydrogen production by 134%–173% and decreasing excess electrical power by 82%–95%. The framework herein may be used to determine the optimal VRE:E capacity and VRE mix for dynamically operated green hydrogen systems.
Techno-Economic Analysis of Hydrogen–Natural Gas Blended Fuels for 400 MW Combined Cycle Power Plants (CCPPs)
Sep 2023
Publication
Various research and development activities are being conducted to use hydrogen an environmentally friendly fuel to achieve carbon neutrality. Using natural gas–hydrogen blends has advantages such as the usage of traditional combined cycle power plant (CCPP) technology and existing natural gas piping infrastructure. Therefore we conducted CCPP process modeling and economic analysis based on natural gas–hydrogen blends. For process analysis we developed a process model for a 400 MW natural gas CCPP using ASPEN HYSYS and confirmed an error within the 1% range through operation data validation. For economic analysis we comparatively reviewed the levelized cost of electricity (LCOE) of CCPPs using hydrogen blended up to 0.5 mole fraction. For LCOE sensitivity analysis we used fuel cost capital expenditures capacity factor and power generation as variables. LCOE is 109.15 KRW/kWh when the hydrogen fuel price is 2000 KRW/kg and the hydrogen mole fraction is increased to 0.5 a 5% increase from the 103.9 KRW/kWh of CCPPs that use only natural gas. Economic feasibility at the level of 100% natural gas CCPPs is possible by reducing capital expenditures (CAPEX) by at least 20% but net output should be increased by at least 5% (20.47 MW) when considering only performance improvement.
Hydrogen Towards Sustainable Transition: A Review of Production, Economic, Environmental Impact and Scaling Factors
Sep 2023
Publication
Currently meeting the global energy demand is largely dependent on fossil fuels such as natural gas coal and oil. Fossil fuels represent a danger to the Earth’s environment and its biological systems. The utilisation of these fuels results in a rise in atmospheric CO2 levels which in turn triggers global warming and adverse changes in the climate. Furthermore these represent finite energy resources that will eventually deplete. There is a pressing need to identify and harness renewable energy sources as a replacement for fossil fuels in the near future. This shift is expected to have a minimal environmental impact and would contribute to ensuring energy security. Hydrogen is considered a highly desirable fuel option with the potential to substitute depleting hydrocarbon resources. This concise review explores diverse methods of renewable hydrogen production with a primary focus on solar wind geothermal and mainly water-splitting techniques such as electrolysis thermolysis photolysis and biomass-related processes. It addresses their limitations and key challenges hampering the global hydrogen economy’s growth including clean value chain creation storage transportation production costs standards and investment risks. The study concludes with research recommendations to enhance production efficiencies and policy suggestions for governments to mitigate investment risks while scaling up the hydrogen economy.
Model-based Economic Analysis of Off-grid Wind/Hydrogen Systems
Sep 2023
Publication
Hydrogen has emerged in the context of large-scale renewable uptake and deep decarbonization. However the high cost of splitting water into hydrogen using renewable energy hinders the development of green hydrogen. Here we provide a cost analysis of hydrogen from off-grid wind. It is found that the current cost evaluation can be improved by examining the operational details of electrolysis. Instead of using low-resolution wind-speed data and linear electrolysis models we generate 5-min resolution wind data and utilize detailed electrolysis models that can describe the safe working range startup time and efficiency variation. Economic assessments are performed over 112 locations in seven countries to demonstrate the influence of operational models. It is shown that over-simplified models lead to less reliable results and the relative error can be 63.65% at most. Further studies have shown the global picture of producing green hydrogen. Based on the improved model we find that the levelized cost of hydrogen ranges from 1.66$/kg to 13.61$/kg. The wind-based hydrogen is cost-competitive in areas with abundant resources and lower investment cost such as China and Denmark. However it is still costly in most of the studied cases. An optimal sizing strategy or involving a battery as electricity storage can further reduce the hydrogen cost the effectiveness of which is location-specific. The sizing strategies of electrolyzers differ by country and rely on the specific wind resource. In contrast the sizing of batteries presents similar trends. Smaller batteries are preferred in almost all the investigated cases.
Experimental Activities on a Hydrogen-Fueled Spark-Ignition Engine for Light-Duty Applications
Nov 2023
Publication
The increase in the overall global temperature and its subsequent impact on extreme weather events are the most critical consequences of human activity. In this scenario transportation plays a significant role in greenhouse gas (GHG) emissions which are the main drivers of climate change. The decline of non-renewable energy sources coupled with the aim of reducing GHG emissions from fossil fuels has forced a shift towards a net-zero emissions economy. As an example of this transition the European Union has set 2050 as the target for achieving carbon neutrality. Hydrogen (H2 ) is gaining increasing relevance as one of the most promising carbon-free energy vectors. If produced from renewable sources it facilitates the integration of various alternative energy sources for achieving a carbon-neutral economy. Recently interest in its application to the transportation sector has grown including different power plant concepts such as fuel cells or internal combustion engines. Despite exhibiting significant drawbacks such as low density combustion instabilities and incompatibilities with certain materials hydrogen is destined to become one of the future fuels. In this publication experimental activities are reported that were conducted on a sparkignition engine fueled with hydrogen at different operating points. The primary objective of this research is to gain a better understanding of the thermodynamic processes that control combustion and their effects on engine performance and pollutant emissions. The results show the emission levels performance and combustion characteristics under different conditions of dilution load and injection strategy and timing.
Hydrogen-Powered Aircraft at Airports: A Review of the Infrastructure Requirements and Planning Challenges
Nov 2023
Publication
Hydrogen-fueled aircraft are a promising innovation for a sustainable future in aviation. While hydrogen aircraft design has been widely studied research on airport requirements for new infrastructure associated with hydrogen-fueled aircraft and its integration with existing facilities is scarce. This study analyzes the current body of knowledge and identifies the planning challenges which need to be overcome to enable the operation of hydrogen flights at airports. An investigation of the preparation of seven major international airports for hydrogen-powered flights finds that although there is commitment airports are not currently prepared for hydrogen-based flights. Major adjustments are required across airport sites covering land use plans airside development utility infrastructure development and safety security and training. Developments are also required across the wider aviation industry including equipment updates such as for refueling and ground support and supportive policy and regulations for hydrogen-powered aircraft. The next 5–10 years is identified from the review as a critical time period for airports given that the first commercial hydrogen-powered flight is likely to depart in 2026 and that the next generation of short-range hydrogen-powered aircraft is predicted to enter service between 2030 and 2035.
Investigation of Performance of Anion Exchange Membrane (AEM) Electrolysis with Different Operating Conditions
Mar 2023
Publication
In this work the performance of anion exchange membrane (AEM) electrolysis is evaluated. A parametric study is conducted focusing on the effects of various operating parameters on the AEM efficiency. The following parameters—potassium hydroxide (KOH electrolyte concentration (0.5–2.0 M) electrolyte flow rate (1–9 mL/min) and operating temperature (30–60 ◦C)—were varied to understand their relationship to AEM performance. The performance of the electrolysis unit is measured by its hydrogen production and energy efficiency using the AEM electrolysis unit. Based on the findings the operating parameters greatly influence the performance of AEM electrolysis. The highest hydrogen production was achieved with the operational parameters of 2.0 M electrolyte concentration 60 ◦C operating temperature and 9 mL/min electrolyte flow at 2.38 V applied voltage. Hydrogen production of 61.13 mL/min was achieved with an energy consumption of 48.25 kW·h/kg and an energy efficiency of 69.64%.
Heat Pumps for Germany—Additional Pressure on the Supply–Demand Equilibrium and How to Cope with Hydrogen
Jun 2024
Publication
In the context of the German Energiewende the current government intends to install six million heat pumps by 2030. Replacing gas heating by power has significant implications on the infrastructure. One of the biggest advantages of using gas is the existing storage portfolio. It has not been clarified yet how power demand should be structured on an annual level—especially since power storage is already a problem and solar power is widely promoted to fuel heat pumps despite having an inverse profile. In this article three different solutions namely hydrogen batteries and carbon capture and storage are discussed with respect to resources energy and financial demand. It shows that relying solely on batteries or hydrogen is not solving the structuring problem. A combination of all existing technologies (including fossil fuels) is required to structure the newly generated electricity demand
Identifying Social Aspect Related to the Hydrogen Economy: Review, Synthesis, and Research Perspectives
Oct 2023
Publication
Energy transition will reshape the power sector and hydrogen is a key energy carrier that could contribute to energy security. The inclusion of sustainability criteria is crucial for the adequate design/deployment of resilient hydrogen networks. While cost and environmental metrics are commonly included in hydrogen models social aspects are rarely considered. This paper aims to identify the social criteria related to the hydrogen economy by using a systematic hybrid literature review. The main contribution is the identification of twelve social aspects which are described ranked and discussed. “Accessibility” “Information” “H2 markets” and “Acceptability” are now emerging as the main themes of hydrogen-related social research. Identified gaps are e.g. lack of the definition of the value of H2 for society insufficient research for “socio-political” aspects (e.g. geopolitics wellbeing) scarce application of social lifecycle assessment and the low amount of works with a focus on social practices and cultural issues.
Dynamic Simulation and Thermoeconomic Analysis of a Power to Gas System
Sep 2023
Publication
Power to gas technology is an innovative solution to promote the use of renewable energy technologies also including e-fuels. This work presents a techno-economic analysis of a novel concept of a renewable power to gas plant. A 2.4 MW solid oxide electrolyzer fed by a 3.1 MW photovoltaic field is coupled with a biomethane production unit to produce synthetic methane by means of a 2.4 MW methanation unit. The hydrogen produced by the electrolyzer is used for the methanation reaction aiming at producing natural gas at net zero carbon emissions. The CO2 is obtained as a byproduct of the membrane separation in a biogas upgrading unit. The methanation unit and the electrolyzer models are developed in MatLab and integrated in TRNSYS to perform a dynamic simulation of all the components and the system as a whole. Dynamic simulation results show a 42% increase in the production of natural gas from renewable energy sources. The thermoeconomic analysis shows a remarkable primary energy saving index of 176% and a total amount of 896 tons of CO2 equivalent emissions saved. As expected the critical point is the economic feasibility since the simple payback is 9 years in case local incentives and subsidies are considered. The parametric analysis on the photovoltaic capacity shows that the simple payback dramatically depends on such design parameter varying from 6 years in the best case scenario to 92 years in the worst case scenario.
Research Progress and Prospects on Hydrogen Damage in Welds of Hydrogen-Blended Natural Gas Pipelines
Nov 2023
Publication
Hydrogen energy represents a crucial pathway towards achieving carbon neutrality and is a pivotal facet of future strategic emerging industries. The safe and efficient transportation of hydrogen is a key link in the entire chain development of the hydrogen energy industry’s “production storage and transportation”. Mixing hydrogen into natural gas pipelines for transportation is the potential best way to achieve large-scale long-distance safe and efficient hydrogen transportation. Welds are identified as the vulnerable points in natural gas pipelines and compatibility between hydrogen-doped natural gas and existing pipeline welds is a critical technical challenge that affects the global-scale transportation of hydrogen energy. Therefore this article systematically discusses the construction and weld characteristics of hydrogen-doped natural gas pipelines the research status of hydrogen damage mechanism and mechanical property strengthening methods of hydrogen-doped natural gas pipeline welds and points out the future development direction of hydrogen damage mechanism research in hydrogen-doped natural gas pipeline welds. The research results show that: 1 Currently there is a need for comprehensive research on the degradation of mechanical properties in welds made from typical pipe materials on a global scale. It is imperative to systematically elucidate the mechanism of mechanical property degradation due to conventional and hydrogeninduced damage in welds of high-pressure hydrogen-doped natural gas pipelines worldwide. 2 The deterioration of mechanical properties in welds of hydrogen-doped natural gas pipelines is influenced by various components including hydrogen carbon dioxide and nitrogen. It is necessary to reveal the mechanism of mechanical property deterioration of pipeline welds under the joint participation of multiple damage mechanisms under multi-component gas conditions. 3 Establishing a fundamental database of mechanical properties for typical pipeline steel materials under hydrogen-doped natural gas conditions globally is imperative to form a method for strengthening the mechanical properties of typical high-pressure hydrogen-doped natural gas pipeline welds. 4 It is essential to promptly develop relevant standards for hydrogen blending transportation welding technology as well as weld evaluation testing and repair procedures for natural gas pipelines.
Exploring Hydrogen Storage Potentital in Depleted Western Australian Hydrocarbon Reservoirs: A Petrophysical and Petrographic Analysis
Oct 2023
Publication
Hydrogen recognised as a clean and sustainable energy carrier with excellent transportation fuel properties drives numerous countries towards a hydrogen-based economy due to its high utilisation efficiency and minimal environmental impact. However the gaseous nature of hydrogen necessitates larger storage surface areas. Underground Hydrogen Storage (UHS) has emerged as a promising and efficient method to overcome this challenge. Currently only a handful of UHS locations exist globally due to the novelty of this field. With its abundant depleted hydrocarbon reservoirs boasting significant storage capacity Western Australia presents a suitable region for hydrogen storage. This paper comprehensively analyses petrophysical and petrographic characteristics employing XRD MIP and Micro-CT techniques on sandstone and claystone samples obtained from several fields in Western Australia. The suitability of these samples for hydrogen storage is evaluated based on mineral composition and porosity. The analysis reveals that more than 96% of Quartz is present in the sandstone samples. The claystone samples exhibit a mineral composition comprising Quartz Calcite K-feldspar Kaolinite Pyrite Albite and Muscovite. The study suggests that hydrogen storage in formation rock is favourable due to the low reactivity of hydrogen with silicate minerals but interactions with cap rock minerals should be considered. Micro-CT results indicate the connected porosity in the 17.23–4.67% range. Pore distribution in sandstones ranges from nanometers to millimetres with a substantial proportion of connected pores in the intermediate range which is conducive to hydrogen storage. This is particularly advantageous as the hydrogen-water system is highly water-wet with hydrogen primarily occupying medium and larger pores minimising hydrogen trapping. In claystone most pores were below 3 nm but instrumental constraints limited their quantification. In conclusion the petrophysical and petrographic analysis underscores the potential of Western Australian depleted hydrocarbon reservoirs for hydrogen storage. Understanding the mineralogical reactions with cap rock minerals is crucial while the favourable pore distribution in sandstones further supports the viability of hydrogen storage.
Performance and Emission Optimisation of an Ammonia/ Hydrogen Fuelled Linear Joule Engine Generator
Mar 2024
Publication
This paper presents a Linear Joule Engine Generator (LJEG) powered by ammonia and hydrogen co-combustion to tackle decarbonisation in the electrification of transport propulsion systems. A dynamic model of the LJEG which integrates mechanics thermodynamics and electromagnetics sub-models as well as detailed combustion chemistry analysis for emissions is presented. The dynamic model is integrated and validated and the LJEG performance is optimised for improved performance and reduced emissions. At optimal conditions the engine could generate 1.96 kWe at a thermal efficiency of 34.3% and an electrical efficiency of 91%. It is found that the electromagnetic force of the linear alternator and heat addition from the external combustor and engine valve timing have the most significant influences on performance whereas the piston stroke has a lesser impact. The impacts of hydrogen ratio oxygen concentration inlet pressure and equivalence ratio of ammonia-air on nitric oxide (NO) formation and reduction are revealed using a detailed chemical kinetic analysis. Results indicated that rich combustion and elevated pressure are beneficial for NO reduction. The rate of production analysis indicates that the equivalence ratio significantly changes the relative contribution among the critical NO formation and reduction reaction pathways.
Environmental Life-Cycle Assessment of Eco-Friendly Alternative Ship Fuels (MGO, LNG, and Hydrogen) for 170 GT Nearshore Ferry
May 2022
Publication
With increasing concerns about environmental pollution the shipping industry has been considering various fuels as alternative power sources. This paper presents a study of the holistic environmental impacts of eco-friendly alternative ship fuels of marine gas oil (MGO) liquefied natural gas (LNG) and hydrogen across each of their life cycles from their production to the operation of the ship. The environmental impacts of the fuels were estimated by life-cycle assessment (LCA) analysis in the categories of well-to-tank tank-to-wake and well-to-wake phases. The LCA analysis was targeted for a 170 gross tonnage (GT) nearshore ferry operating in the ROK which was conceptually designed in the study to be equipped with the hydrogen fuel cell propulsion system. The environmental impact performance was presented with comparisons for the terms of global warming potential (GWP) acidification potential (AP) photochemical ozone creation potential (POCP) eutrophication potential (EP) and particulate matter (PM). The results showed that the hydrogen showed the highest GWP level during its life cycle due to the large amount of emissions in the hydrogen generation process through the steam methane reforming (SMR) method. The paper concludes with suggestions of an alternative fuel for the nearshore ferry and its production method based on the results of the study.
Future Energy Scenarios 2019
Jul 2019
Publication
Decarbonising energy is fundamental in the transition towards a sustainable future. Our Future Energy Scenarios aim to stimulate debate to inform the decisions that will help move us towards achieving carbon reduction targets and ultimately shape the energy system of the future.
Liquefied Hydrogen Value Chain: A Detailed Techno-economic Evaluation for its Application in the Industrial and Mobility Sectors
Oct 2023
Publication
Green hydrogen can be efficiently produced in regions rich in renewable sources far from the European largeproduction sites and delivered to the continent for utilization in the industrial and mobility sectors. In this work the transportation of hydrogen from North Africa to North Italy in its liquefied form is considered. A technoeconomic assessment is performed on its value chain which includes liquefaction storage maritime transport distribution regasification and compression. The calculated transport cost for the industrial application (delivery to a hydrogen valley) ranges from 6.14 to 9.16 €/kg while for the mobility application (delivery to refueling stations) the range is 10.96–17.71 €/kg. In the latter case the most cost-effective configuration involves the distribution of liquefied hydrogen and regasification at the refueling stations. The liquefaction process is the cost driver of the value chain in all the investigated cases suggesting the importance of its optimization to minimize the overall transport cost.
Hydrogen Production, Storage, Utilisation and Environmental Impacts: A Review
Oct 2021
Publication
Dihydrogen (H2) commonly named ‘hydrogen’ is increasingly recognised as a clean and reliable energy vector for decarbonisation and defossilisation by various sectors. The global hydrogen demand is projected to increase from 70 million tonnes in 2019 to 120 million tonnes by 2024. Hydrogen development should also meet the seventh goal of ‘affordable and clean energy’ of the United Nations. Here we review hydrogen production and life cycle analysis hydrogen geological storage and hydrogen utilisation. Hydrogen is produced by water electrolysis steam methane reforming methane pyrolysis and coal gasification. We compare the environmental impact of hydrogen production routes by life cycle analysis. Hydrogen is used in power systems transportation hydrocarbon and ammonia production and metallugical industries. Overall combining electrolysis-generated hydrogen with hydrogen storage in underground porous media such as geological reservoirs and salt caverns is well suited for shifting excess of-peak energy to meet dispatchable on-peak demand.
Assessment of Greenhouse Gas Emissions from Hydrogen Production Processes: Turquoise Hydrogen vs. Steam Methane Reforming
Nov 2022
Publication
Hydrogen has received substantial attention because of its diverse application in the energy sector. Steam methane reforming (SMR) dominates the current hydrogen production and is the least expensive endothermic reaction to produce grey hydrogen. This technology provides the advantages of low cost and high energy efficiency; however it emits an enormous amount of CO2. Carbon capture storage (CCS) technology helps reduce these emissions by 47% to 53% producing blue hydrogen. Methane pyrolysis is an alternative to SMR that produces (ideally) CO2-free turquoise hydrogen. In practice methane pyrolysis reduces CO2 emissions by 71% compared to grey hydrogen and 46% compared to blue hydrogen. While carbon dioxide emissions decrease with CCS fugitive methane emissions (FMEs) for blue and turquoise hydrogen are higher than those for grey hydrogen because of the increased use of natural gas to power carbon capture. We undertake FMEs of 3.6% of natural gas consumption for individual processes. In this study we also explore the utilization of biogas as a feedstock and additional Boudouard reactions for efficient utilization of solid carbon from methane pyrolysis and carbon dioxide from biogas. The present study focuses on possible ways to reduce overall emissions from turquoise hydrogen to provide solutions for a sustainable low-CO2 energy source.
Effects of Fuel Cell Size and Dynamic Limitations on the Durability and Efficiency of Fuel Cell Hybrid Electric Vehicles under Driving Conditions
Mar 2024
Publication
In order to enhance the durability of fuel cell systems in fuel cell hybrid electric vehicles (FCHEVs) researchers have been dedicated to studying the degradation monitoring models of fuel cells under driving conditions. To predict the actual degradation factors and lifespan of fuel cell systems a semi-empirical and semi-physical degradation model suitable for automotive was proposed and developed. This degradation model is based on reference degradation rates obtained from experiments under known conditions which are then adjusted using coefficients based on the electrochemical model. By integrating the degradation model into the vehicle simulation model of FCHEVs the impact of different fuel cell sizes and dynamic limitations on the efficiency and durability of FCHEVs was analyzed. The results indicate that increasing the fuel cell stack power improves durability while reducing hydrogen consumption but this effect plateaus after a certain point. Increasing the dynamic limitations of the fuel cell leads to higher hydrogen consumption but also improves durability. When considering only the rated power of the fuel cell a comparison between 160 kW and 100 kW resulted in a 6% reduction in hydrogen consumption and a 10% increase in durability. However when considering dynamic limitation factors comparing the maximum and minimum limitations of a 160 kW fuel cell hydrogen consumption increased by 10% while durability increased by 83%.
Optimal Parameter Determination of Membrane Bioreactor to Boost Biohydrogen Production-Based Integration of ANFIS Modeling and Honey Badger Algorithm
Jan 2023
Publication
Hydrogen is a new promising energy source. Three operating parameters including inlet gas flow rate pH and impeller speed mainly determine the biohydrogen production from membrane bioreactor. The work aims to boost biohydrogen production by determining the optimal values of the control parameters. The proposed methodology contains two parts: modeling and parameter estimation. A robust ANIFS model to simulate a membrane bioreactor has been constructed for the modeling stage. Compared with RMS thanks to ANFIS the RMSE decreased from 2.89 using ANOVA to 0.0183 using ANFIS. Capturing the proper correlation between the inputs and output of the membrane bioreactor process system encourages the constructed ANFIS model to predict the output performance exactly. Then the optimal operating parameters were identified using the honey badger algorithm. During the optimization process inlet gas flow rate pH and impeller speed are used as decision variables whereas the biohydrogen production is the objective function required to be maximum. The integration between ANFIS and HBA boosted the hydrogen production yield from 23.8 L to 25.52 L increasing by 7.22%.
Hydrogen in the Strategies of the European Union Member States
Jan 2021
Publication
Energy and environmental challenges are two key issues related to the sustainable development of the Earth. Fossil fuels (oil coal and natural gas) still supply more than 85% of world energy consumption. Several nations around the globe are striving to provide access to clean and sustainable energy by 2030 (Hostettler et al. 2015). When the Paris Agreement entered into force in 2016 many countries have recently announced serious commitments to significantly reduce their carbon dioxide emissions promising to achieve “net zero” by 2050. he main goal is to limit global warming to well below 2 degrees Celsius preferably to 1.5 degrees Celsius compared to pre-industrial levels (IEA 2021). his requires a total transformation of the energy systems that underpin our economies. In the case of renewable energy technology deployment hydrogen may provide a complementary solution due to its flexibility as an energy carrier and storage medium. The European Union (EU) a signatory to the Paris Agreement demonstrated interest in hydrogen as an invaluable raw material in considerably reducing CO2 emissions. Hydrogen inthe EU energy mix is estimated to increase from the current level (less than 2%) to 13–14% in 2050 (EC 2018).
Fuelling the Transition Podcast: Using Hydrogen to Achieve Net-zero
Jan 2021
Publication
In order to achieve the EU’s target of 55% carbon reduction by 2030 hydrogen will have to make a key contribution to the energy mix. With many applications in industrial heat mobility power and chemical refineries hydrogen can be used to decarbonise where electrification is not possible. Equinor is a broad energy company with 21000 employees developing oil gas wind and solar energy in more than 30 countries worldwide. Equinor have been at the forefront of promoting hydrogen projects in Europe and developing low-carbon hydrogen solutions. In this episode Johan Leuraers Chief Consultant - Policy and Regulatory Affairs at Equinor and John Williams Head of Hydrogen Expertise Cluster at AFRY Management Consulting join us to discuss the main barriers to the uptake of hydrogen and the next steps to kick-start the hydrogen economy.
The podcast can be found on their website.
The podcast can be found on their website.
Decarbonisation of Heat and the Role of ‘Green Gas’ in the United Kingdom
May 2018
Publication
This paper looks at the possible role of ‘green gas’ in the decarbonisation of heat in the United Kingdom. The option is under active discussion at the moment because of the UK’s rigorous carbon reduction targets and the growing realisation that there are problems with the ‘default’ option of electrifying heat. Green gas appears to be technically and economically feasible. However as the paper discusses there are major practical and policy obstacles which make it unlikely that the government will commit itself to developing ‘green gas’ in the foreseeable future.
Future Energy Scenarios 2018
Jul 2018
Publication
Welcome to our Future Energy Scenarios. These scenarios which stimulate debate and help inform the decisions that will shape our energy future have never been more important – especially when you consider the extent to which the energy landscape is being transformed.
Location Optimization of Hydrogen Refueling Stations in Hydrogen Expressway Based on Hydrogen Supply Chain Cost
Jan 2021
Publication
Hydrogen energy is regarded as an important way to achieve carbon emission reduction. This paper focuses on the combination of the design of the hydrogen supply chain network and the location of hydrogen refueling stations on the expressway. Based on the cost analysis of the hydrogen supply chain a multi-objective model is developed to determine the optimal scale and location of hydrogen refueling stations on the hydrogen expressway. The proposed model considers the hydrogen demand forecast hydrogen source selection hydrogen production and storage and transportation hydrogen station refueling mode etc. Taking Dalian City China as an example with offshore wind power as a reliable green hydrogen supply to select the location and capacity of hydrogen refueling stations for the hydrogen energy demonstration section of a certain expressway under multiple scenarios. The results of the case show that 4 and 5 stations are optimized on the expressway section respectively and the unit hydrogen cost is $14.3 /kg H2 and $11.8 /kg H2 respectively which are equal to the average hydrogen price in the international range. The optimization results verify the feasibility and effectiveness of the model.
Fuelling the Transition Podcast: How Will Hydrogen Heat and Safety in the Home?
Jan 2022
Publication
In this episode Angela Needle Director of Strategy at Cadent and John Williams Head of Hydrogen Expertise Cluster at AFRY Management Consulting join us to discuss a range of topics concerning hydrogen and the energy transition. This includes Cadent’s involvement in hydrogen through HyNet the role of hydrogen in heat safety and plans for the first hydrogen village. They also explore Angela’s role as co-founder of the Women’s Utilities Network a group focussed on helping women develop their skills within the energy space.
The podcast can be found on their website.
The podcast can be found on their website.
The Origin and Occurrence of Natural Hydrogen
Mar 2023
Publication
Hydrogen is an attractive clean sustainable energy source primarily produced via industry. At present most reviews on hydrogen mainly focus on the preparation and storage of hydrogen while the development and utilization of natural hydrogen will greatly reduce its cost. Natural hydrogen has been discovered in many geological environments. Therefore based on extensive literature research in this study the distribution and sources of natural hydrogen were systematically sorted and the identification method and occurrence state of natural hydrogen were examined and summarized. The results of this research show that hydrogen has been discovered in oceanic spreading centers transform faults passive margins convergent margins and intraplate settings. The primary sources of the hydrogen include alterations in Fe(II)-containing rocks the radiolysis of water degassed magma and the reaction of water- and silica-containing rocks during the mechanical fracturing. Hydrogen can appear in free gas it can be adsorbed and trapped in inclusions. Currently natural hydrogen exploration is in its infancy. This systematic review helps to understand the origin distribution and occurrence pattern of natural hydrogen. In addition it facilitates the exploration and development of natural hydrogen deposits thus enabling the production of low-cost hydrogen.
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