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The Effect of Hydrogen Addition on the Pollutant Emissions of a Marine Internal Combustion Engine Genset
Sep 2022
Publication
Hydrogen as a maritime fuel is one of the solutions that will assist the shipping sector in addressing the challenges regarding decarbonization taking into consideration the targets set for 2030 and 2050. The extensive utilization of hydrogen requires massive production of green hydrogen and the development of proper infrastructure to support a sustainable supply chain. An alternative solution is based on the on-board production of hydrogen where production units are installed on-board the vessel. Along these lines the HYMAR project aims to test the utilization of a hydrogen production unit for on-board use. The article deals with the use of hydrogen as a fuel for internal combustion engines taking into consideration reports from literature and the preliminary results of the HYMAR project focusing on the environmental impact and the reduction in emissions. Experimental investigation on a marine auxiliary engine for power generation under the HYMAR project leads to promising results regarding the environmental footprint of the internal combustion engine when hydrogen is added in the fuel mix with increasing percentages.
Ammonia: Zero-carbon Fertiliser, Fuel and Energy Storage
Feb 2020
Publication
This briefing considers the opportunities and challenges associated with the manufacture and future use of zero-carbon ammonia which is referred to in this report as green ammonia. The production of green ammonia has the capability to impact the transition towards zero-carbon through the decarbonisation of its current major use in fertiliser production. Perhaps as significantly it has the following potential uses: • As a medium to store and transport chemical energy with the energy being released either by directly reacting with air or by the full or partial decomposition of ammonia to release hydrogen. • As a transport fuel by direct combustion in an engine or through chemical reaction with oxygen in the air in a fuel cell to produce electricity to power a motor. • To store thermal energy through the absorption of water and through phase changes between material states (for example liquid to gas).
Smart Power-to-gas Deployment Strategies Informed by Spatially Explicit Cost and Value Models
Oct 2022
Publication
Green hydrogen allows coupling renewable electricity to hard-to-decarbonize sectors such as long-distance transport and carbon-intensive industries in order to achieve net zero emissions. Evaluating the cost and value of power-to-gas is a major challenge owing to the spatial distribution and temporal variability of renewable electricity CO2 and energy demand. Here we propose a method based on geographic information system (GIS) and techno-economic modeling to: (i) compare the levelized cost and levelized value of power-to-gas across locations; (ii) identify potential hotspots for their future implementation in Switzerland; and (iii) set cost improvement targets as well as smart deployment strategies. Our method accounts for the spatial and temporal (both hourly and seasonal) availability of renewable electricity and CO2 sources as well as the presence of gas infrastructure heating networks oxygen and gas demand centers. We find that only green hydrogen plants connected directly to run-of-river hydropower plants are currently profitable in Switzerland (with NPV per CAPEX ranging between 2.3-5.6). However considering technological progress by 2050 a few green hydrogen plants deployed in the demand centers and powered by rooftop PV electricity will also become economically attractive. Moreover a few synthetic methane plants connected to run-of-river hydropower plants currently show slight profitability (NPV per CAPEX reaching values up to 1.3) and in 2050 (NPV per CAPEX up to 3.1) whereas those connected to rooftop PV will remain uneconomical even in 2050. Based on our findings we devise a long-term roadmap for policy makers and project developers to plan future green hydrogen projects. The proposed methodology which is applied to Switzerland can be extended to other countries.
Multi-vector Energy Management System including Scheduling Electrolyser, Electric Vehicle Charging Station and Other Assets in a Real Scenario
Oct 2022
Publication
Today in the field of energy the main goal is to reduce emissions with 7 the aim of maintaining a clean environment. To reduce energy consumption 8 from fossil fuels new tools for micro-grids have been proposed. In the context 9 of multi-vector energy management systems the present work proposes an 10 optimal scheduler based on genetic algorithms to manage flexible assets in the 11 energy system such as energy storage and manageable demand. This tool is 12 applied to a case study for a Spanish technology park (360 kW consumption 13 peak) with photovoltaic and wind generation (735 kW generation peak) 14 hydrogen production (15 kW) and electric and fuel cell charging stations. 15 It provides an hourly day-ahead scheduling for the existing flexible assets: 16 the electrolyser the electric vehicle charging station the hydrogen refuelling 17 station and the heating ventilation and air conditioning system in one 18 building of the park. 19 A set of experiments is carried out over a period of 14 days using real 20 data and performing computations in real time in order to test and validate 21 the tool. The analysis of results show that the solution maximises the use of 22 local renewable energy production (demand is shifted to those hours when 23 there is a surplus of generation) which means a reduction in energy costs 24 whereas the computational cost allows the implementation of the tool in real 25 time.
Modelling and Performance Analysis of an Autonomous Marine Vehicle Powered by a Fuel Cell Hybrid Powertrain
Sep 2022
Publication
This paper describes the implementation of a hydrogen-based system for an autonomous surface vehicle in an effort to reduce environmental impact and increase driving range. In a suitable computational environment the dynamic electrical model of the entire hybrid powertrain consisting of a proton exchange membrane fuel cell a hydrogen metal hydride storage system a lithium battery two brushless DC motors and two control subsystems is implemented. The developed calculation tool is used to perform the dynamic analysis of the hybrid propulsion system during four different operating journeys investigating the performance achieved to examine the obtained performance determine the feasibility of the work runs and highlight the critical points. During the trips the engine shows fluctuating performance trends while the energy consumption reaches 1087 Wh for the fuel cell (corresponding to 71 g of hydrogen) and 370 Wh for the battery consuming almost all the energy stored on board.
Velocity Measurements of Hydrogen Jets Using the Optical Flow Method
Sep 2021
Publication
Concentration and velocity measurements are crucial for developing and validating hydrogen jet models which provide scientific bases for hydrogen safety analyses. The concentration fields have been visualized and accurately measured using laser diagnostic methods based on lase Rayleigh and Raman scattering techniques. However the velocity measurements are more challenging. Particle image velocimetry (PIV) has been commonly used for measuring velocities in turbulent flows by seeding tracer particles into the flow and assuming the particles intimately following the flow. However sometimes the particle seeding is difficult or disturbs the flow. Moreover simultaneously concentration and velocity measurements are very difficult when using PIV systems to measure the velocities. Therefore the optical flow velocimetry (OFV) method was used to resolve the velocity fields from the scalar fields or particle images of hydrogen jets. In the present work the velocity field and particle images of hydrogen jets were simulated using FLUENT with the large eddy simulation (LES) model and the particle images were then used to resolve the velocity field by the OFV method. The OFV results were compared with the CFD simulations to verify their accuracy. The results show that the OFC method was an efficient low-cost way to extract the velocity fields from particle images. The OFV method accurately located the large vortices in the flow and the velocity distribution of the high-velocity gradients regions was consistent with the CFD results. The present study lays a foundation for using the OFV method to directly resolve the velocity fields from the concentration fields of hydrogen jets measured by laser diagnostics.
Evolutions in Hydrogen and Fuel Cell Standardization: The HarmonHy Experience
Dec 2007
Publication
HarmonHy is a European Union-funded Specific Support Action aiming to make an assessment of the activities on hydrogen and fuel cell regulations codes and standards (RCS) on a worldwide level. On this basis gaps have been identified and potential conflicts between regulations codes and standards have been investigated. Types of document to be referred to include international regional and national standards EU directives UNECE regulations… Particular attention will be paid to the identification of the needs for standards as perceived by the industry as well as to actions aiming to ensure concordance between standards codes and regulations. Standards and regulations require harmonization. HarmonHy pursues the elaboration of an action plan and a roadmap for future work on harmonizing regulations codes and standards on hydrogen and fuel cells on an international level.
A Positive Shift in the Public Acceptability of a Low-Carbon Energy Project After Implementation: The Case of a Hydrogen Fuel Station
Apr 2019
Publication
Public acceptability of low-carbon energy projects is often measured with one-off polls. This implies that opinion-shifts over time are not always taken into consideration by decision makers relying on these polls. Observations have given the impression that public acceptability of energy projects increases after implementation. However this positive shift over time has not yet been systematically studied and is not yet understood very well. This paper aims to fill this gap. Based on two psychological mechanisms loss aversion and cognitive dissonance reduction we hypothesize that specifically people who live in proximity of a risky low-carbon technology—a hydrogen fuel station (HFS) in this case—evaluate this technology as more positive after its implementation than before. We conducted a survey among Dutch citizen living nearby a HFS and indeed found a positive shift in the overall evaluation of HFS after implementation. We also found that the benefits weighed stronger and the risks weaker after the implementation. This shift did not occur for citizens living further away from the HFS. The perceived risks and benefits did not significantly change after implementation neither for citizens living in proximity nor for citizens living further away. The societal implications of the findings are discussed.
Light-Driven Hydrogen Evolution Assisted by Covalent Organic Frameworks
Jun 2021
Publication
Covalent organic frameworks (COFs) are crystalline porous organic polymers built from covalent organic blocks that can be photochemically active when incorporating organic semiconducting units such as triazine rings or diacetylene bridges. The bandgap charge separation capacity porosity wettability and chemical stability of COFs can be tuned by properly choosing their constitutive building blocks by extension of conjugation by adjustment of the size and crystallinity of the pores and by synthetic post-functionalization. This review focuses on the recent uses of COFs as photoactive platforms for the hydrogen evolution reaction (HER) in which usually metal nanoparticles (NPs) or metallic compounds (generally Pt-based) act as co-catalysts. The most promising COF-based photocatalytic HER systems will be discussed and special emphasis will be placed on rationalizing their structure and light-harvesting properties in relation to their catalytic activity and stability under turnover conditions. Finally the aspects that need to be improved in the coming years will be discussed such as the degree of dispersibility in water the global photocatalytic efficiency and the robustness and stability of the hybrid systems putting emphasis on both the COF and the metal co-catalyst.
Expectations as a Key to Understanding Actor Strategies in the Field of Fuel Cell and Hydrogen Vehicles
Feb 2012
Publication
Due to its environmental impact the mobility system is increasingly under pressure. The challenges to cope with climate change air quality depleting fossil resources imply the need for a transition of the current mobility system towards a more sustainable one. Expectations and visions have been identified as crucial in the guidance of such transitions and more specifically of actor strategies. Still it remained unclear why the actors involved in transition activities appear to change their strategies frequently and suddenly. The empirical analysis of the expectations and strategies of three actors in the field of hydrogen and fuel cell technology indicates that changing actor strategies can be explained by rather volatile expectations related to different levels. Our case studies of the strategies of two large car manufacturers and the German government demonstrate that the car manufacturers refer strongly to expectations about the future regime while expectations related to the socio-technical landscape level appear to be crucial for the strategy of the German government.
SGN Project Report - Flame Visibility Risk Assessment
Feb 2021
Publication
This report contains information on the relative risks of natural gas and hydrogen fires particularly regarding their visibility. The fires considered are those that could occur on the H100 Fife trial network. The H100 Fife project will connect a number of residential houses to 100% hydrogen gas supply. The project includes hydrogen production storage and a new distribution network. From a review of large and small-scale tests and incidents it is concluded that hydrogen flames are likely to be clearly visible for releases above 2 bar particularly for larger release rates. At lower pressures hydrogen flame visibility will be affected by ambient lighting background colour and release orientation although this is also the case for natural gas. Potential safety implications from lack of flame visibility are that SGN workers other utility workers or members of the public could inadvertently come into contact with an ignited release. However some releases would be detected through noise thrown soil or interaction with objects. From a workshop and review of risk reduction measures and analysis of historical interference damage incidents it is concluded that flames with the potential for reduced visibility are adequately controlled. This is due to the likelihood of such scenarios occurring being low and that the consequences of coming into contact with such a flame are unlikely to be severe. These conclusions are supported by cost-benefit analysis that shows that no additional risk mitigation measures are justified for the H100 project. It is recommended that the cost-benefit analysis is revisited before applying the approach to a network wider than the H100 project. It was observed that the addition of odorant at relevant concentrations did not have an effect on the visibility of hydrogen flames.
This report and any attachment is freely available on the ENA Smarter Networks Portal here. IGEM Members can download the report and any attachment directly by clicking on the pdf icon above.
This report and any attachment is freely available on the ENA Smarter Networks Portal here. IGEM Members can download the report and any attachment directly by clicking on the pdf icon above.
Integrating a Top-Gas Recycling and CO2 Electrolysis Process for H2-Rich Gas Injection and Reduce CO2 Emissions from an Ironmaking Blast Furnace
Mar 2022
Publication
Introducing CO2 electrochemical conversion technology to the iron-making blast furnace not only reduces CO2 emissions but also produces H2 as a byproduct that can be used as an auxiliary reductant to further decrease carbon consumption and emissions. With adequate H2 supply to the blast furnace the injection of H2 is limited because of the disadvantageous thermodynamic characteristics of the H2 reduction reaction in the blast furnace. This paper presents thermodynamic analysis of H2 behaviour at different stages with the thermal requirement consideration of an iron-making blast furnace. The effect of injecting CO2 lean top gas and CO2 conversion products H2–CO gas through the raceway and/or shaft tuyeres are investigated under different operating conditions. H2 utilisation efficiency and corresponding injection volume are studied by considering different reduction stages. The relationship between H2 injection and coke rate is established. Injecting 7.9–10.9 m3/tHM of H2 saved 1 kg/tHM coke rate depending on injection position. Compared with the traditional blast furnace injecting 80 m3/tHM of H2 with a medium oxygen enrichment rate (9%) and integrating CO2 capture and conversion reduces CO2 emissions from 534 to 278 m3/tHM. However increasing the hydrogen injection amount causes this iron-making process to consume more energy than a traditional blast furnace does.
Safety Analysis and Risk Control of Shore-Based Bunkering Operations for Hydrogen Powered Ships
Sep 2021
Publication
In order to ensure the safety of shore-based hydrogen bunkering operations this paper takes a 2000-ton bulk hydrogen powered ship as an example. Firstly the HAZID method is used to identify the hazards of hydrogen bunkering then the probability of each scenario is analyzed and then the consequences of scenarios with high risk based on FLACS software is simulated. Finally the personal risk of bunkering operation is evaluated and the bunkering restriction area is defined. The results show that the personal risk of shore-based bunkering operation of hydrogen powered ship is acceptable but the following risk control measures should be taken: (1) The bunkering restriction area shall be delineated and only the necessary operators are allowed to enter the area and control the any form of potential ignition source; (2) The hose is the high risk hazards during bunkering. The design form of bunkering arm and bunkering hose is considered to shorten the length of the hose as far as possible; (3) A safe distance between shore-based hydrogenation station and the building outside the station should be guaranteed. The results have a guiding role in effectively reducing the risk of hydrogen bunkering operation.
Methanol Electrolysis for Hydrogen Production Using Polymer Electrolyte Membrane: A Mini-Review
Nov 2020
Publication
Hydrogen (H2) has attained significant benefits as an energy carrier due to its gross calorific value (GCV) and inherently clean operation. Thus hydrogen as a fuel can lead to global sustainability. Conventional H2 production is predominantly through fossil fuels and electrolysis is now identified to be most promising for H2 generation. This review describes the recent state of the art and challenges on ultra-pure H2 production through methanol electrolysis that incorporate polymer electrolyte membrane (PEM). It also discusses about the methanol electrochemical reforming catalysts as well as the impact of this process via PEM. The efficiency of H2 production depends on the different components of the PEM fuel cells which are bipolar plates current collector and membrane electrode assembly. The efficiency also changes with the nature and type of the fuel fuel/oxygen ratio pressure temperature humidity cell potential and interfacial electronic level interaction between the redox levels of electrolyte and band gap edges of the semiconductor membranes. Diverse operating conditions such as concentration of methanol cell temperature catalyst loading membrane thickness and cell voltage that affect the performance are critically addressed. Comparison of various methanol electrolyzer systems are performed to validate the significance of methanol economy to match the future sustainable energy demands.
Strategies for Joint Procurement of Fuel Cell Buses
Jun 2018
Publication
The Fuel Cells and Hydrogen Joint Undertaking (FCH JU) has supported a range of initiatives in recent years designed to develop hydrogen fuel cell buses to a point where they can fulfil their promise as a mainstream zero emission vehicle for public transport.<br/>Within this study 90 different European cities and regions have been supported in understanding the business case of fuel cell bus deployment and across these locations. The study analyses the funding and financing for fuel cell bus deployment to make them become a mainstream zero emission choice for public transport providers in cities and regions across Europe. It also outlines possible solutions for further deployment of FC buses beyond the subsidised phase.<br/>In the light of the experience of the joint tender process in the UK and in Germany the study highlights best practices for ordering fuel cell buses. Other innovative instruments explored in other countries for the orders of large quantities of fuel cells buses are presented: Special Purpose Vehicles and centralised purchase office. Finally the study deeply analyses the funding and financing for fuel cell bus deployment to make them become a mainstream zero emission choice for public transport providers in cities and regions across Europe.
Net Zero and Geospheric Return: Actions Today for 2030 and Beyond
Sep 2020
Publication
In a report co-authored by Columbia University’s Centre on Global Energy Policy (CGEP) and the Global CCS Institute titled ‘Net Zero and Geospheric Return: Actions today for 2030’ findings reveal that climate finance policies and the development of carbon dioxide removal technologies need to grow rapidly within the next 10 years in order to curb climate change and hit net-zero targets.
The report unveils key climate actions required to avoid climate catastrophe:
With 2020 set to close the hottest decade on record CO2 emissions need to drop by 50% to achieve net-zero climate goals by 2030 The rapid deployment of climate mitigating infrastructure needs to occur including the expansion of CO2 pipelines from the current 8000 km to 43000 km by 2030 Clear climate polices which reduce the financial and regulatory risk of CO2 capture and storage and increase CO2 storage options need to be quickly developed and implemented.
Link to document on Global CCS Institute Website
The report unveils key climate actions required to avoid climate catastrophe:
With 2020 set to close the hottest decade on record CO2 emissions need to drop by 50% to achieve net-zero climate goals by 2030 The rapid deployment of climate mitigating infrastructure needs to occur including the expansion of CO2 pipelines from the current 8000 km to 43000 km by 2030 Clear climate polices which reduce the financial and regulatory risk of CO2 capture and storage and increase CO2 storage options need to be quickly developed and implemented.
Link to document on Global CCS Institute Website
Energy Management Strategies for a Zero-emission Hybrid Domestic Ferry
Oct 2021
Publication
The paper presents three approaches for the sizing and control of a maritime hybrid power-plant equipped with proton exchange membrane fuel cells and batteries. The study focuses on three different power-plant configurations including the energy management strategy and the power-plant component sizing. The components sizing is performed following the definition of the energy management strategy using the sequential optimization approach. These configurations are tested using a dynamic model developed in Simulink. The simulations are carried out to validate the technical feasibility of each configuration for maritime use. Each energy management strategy is developed to allow for the optimization of a chosen set of parameters such as hydrogen consumption and fuel cell degradation. It is observed that in the hybrid power-plant optimization there are always trade-offs and the optimization should be carried out by prioritizing primary factors the ship owner considers most important for day-to-day operations.
Non-alloy Mg Anode for Ni-MH Batteries: Multiple Approaches Towards a Stable Cycling Performance
Apr 2021
Publication
Mg attracts much research interest as anode material for Ni-MH batteries thanks to its lightweight cost-effectiveness and high theoretical capacity (2200 mA h g−1). However its practical application is tremendously challenged by the poor hydrogen sorption kinetics passivation from aggressive aqueous electrolytes and insulating nature of MgH2. Mg-based alloys exhibit enhanced hydrogen sorption kinetics and electrical conductivity but significant amount of costly transition metal elements are required. In this work we have for the first time utilized non-alloyed but catalyzed Mg as anode for Ni-MH batteries. 5 mol.% TiF3 was added to nanosized Mg for accelerating the hydrogen sorption kinetics. Several strategies for preventing the problematic passivation of Mg have been studied including protective encapsulation of the electrode and utilizing room-temperature/high-temperature ionic liquids and an alkaline polymer membrane as working electrolyte. Promising electrochemical performance has been achieved in this Mg–TiF3 composite anode based Ni-MH batteries with room for further improvements.
Numerical Analysis on the Mechanism of Blast Mitigation by Water Droplets
Sep 2021
Publication
Hydrogen has a high risk of ignition owing to its extremely low ignition energy and wide range of flammability. Therefore acquiring parameters relating to safe usage is of particular interest. The ignition of hydrogen generates combustion processes such as detonation and deflagration which may produce a blast wave. The severity of injuries sustained from a blast wave is determined by its strength. To reduce the physical hazards caused by explosion there is a need for some concepts for attenuating explosions and blast waves. In the present study we used water droplets as a material to reduce the blast wave strength. Numerical analysis of the interaction between blast waves and water droplets in a shock tube was conducted to understand the mitigation mechanism of blast wave. In this report we numerically modelled the experiment conducted by Mataradze et al. [1] to understand the main factor of blast mitigation by water droplets. In order to quantitatively clarify the mitigation effect of water droplets on the blast wave especially by quasi-steady drag here we conducted parameter studies on water droplet sprayed region. From this calculation it was suggested that the location of water droplet sprayed layer did not affect the blast mitigation effect at far side of the high explosives.
Regional Insights into Low-carbon Hydrogen Scale Up: World Energy Insights Working Paper
May 2022
Publication
Following the release of the “Hydrogen on the Horizon” series in July and September 2021 the World Energy Council in collaboration with EPRI and PwC led a series of regional deep dives to understand regional differences within low-carbon hydrogen development. These regional deep dives aimed to uncover regional perspectives and differing dynamics for low-carbon hydrogen uptake.<br/>Although each region presents its own distinctive challenges and opportunities the deep dives revealed that the “regional paths” provide new insights into the global scaling up of low-carbon hydrogen in the coming years. In addition each region holds its own unique potential in achieving the Sustainable Development Goals.<br/>Key Takeaways:<br/>1. Our new regional insights indicate that low-carbon hydrogen can play a significant role by 2040 across the world by supporting countries’ efforts towards achieving Paris Agreement goals whilst contributing to the diversity and security of their energy portfolios. This would require significant global trade flows of hydrogen and hydrogen-based fuels.<br/>2. The momentum for hydrogen-based fuels is continuing to grow worldwide but differences are seen between regions – based on differing market activities and opportunities.<br/>3. Today moving from “whether” to “how” to develop low-carbon hydrogen highlights significant uncertainties which need to be addressed if hydrogen is to reach its full potential.<br/>Can the challenges in various supply chain options be overcome?<br/>Can hydrogen play a role in tackling climate change in the short term?<br/>Can bankable projects emerge and the gap between engineers and financers be bridged? Can the stability of supply of the main low-carbon hydrogen production sources be guaranteed?<br/>4. Enabling low-carbon hydrogen at scale would notably require greater coordination and cooperation amongst stakeholders worldwide to better mobilise public and private finance and to shift the focus to end-users and people through the following actions:<br/>Moving from production cost to end-use price<br/>Developing Guarantees of Origin schemes with sustainability requirements<br/>Developing a global monitoring and reporting tool on low-carbon hydrogen projects<br/>Better consideration of social impacts alongside economic opportunities
Methane Cracking as a Bridge Technology to the Hydrogen Economy
Nov 2016
Publication
Shifting the fossil fuel dominated energy system to a sustainable hydrogen economy could mitigate climate change through reduction of greenhouse gas emissions. Because it is estimated that fossil fuels will remain a significant part of our energy system until mid-century bridge technologies which use fossil fuels in an environmentally cleaner way offer an opportunity to reduce the warming impact of continued fossil fuel utilization. Methane cracking is a potential bridge technology during the transition to a sustainable hydrogen economy since it produces hydrogen with zero emissions of carbon dioxide. However methane feedstock obtained from natural gas releases fugitive emissions of methane a potent greenhouse gas that may offset methane cracking benefits. In this work a model exploring the impact of methane cracking implementation in a hydrogen economy is presented and the impact on global emissions of carbon dioxide and methane is explored. The results indicate that the hydrogen economy has the potential to reduce global carbon dioxide equivalent emissions between 0 and 27% when methane leakage from natural gas is relatively low methane cracking is employed to produce hydrogen and a hydrogen fuel cell is applied. This wide range is a result of differences between the scenarios and the CH4 leakage rates used in the scenarios. On the other hand when methane leakage from natural gas is relatively high methane steam reforming is employed to produce hydrogen and an internal combustion engine is applied the hydrogen economy leads to a net increase in global carbon dioxide equivalent emissions between 19 and 27%.
Assessment of Fossil-free Steelmaking Based on Direct Reduction Applying High-temperature Electrolysis
Jun 2021
Publication
Preventing humanity from serious impact of climate crisis requires carbon neutrality across all economic sectors including steel industry. Although fossil-free steelmaking routes receiving increasing attention fundamental process aspects especially approaches towards the improvement of efficiency and flexibility are so far not comprehensively studied. In this paper optimized process concepts allowing for a gradual transition towards fossil-free steelmaking based on the coupling of direct reduction process electric arc furnace and electrolysis are presented. Both a high-temperature and low-temperature electrolysis were modeled and possibilities for the integration into existing infrastructure are discussed. Various schemes for heat integration especially when using high-temperature electrolysis are highlighted and quantified. It is demonstrated that the considered direct reduction-based process concepts allow for a high degree of flexibility in terms of feed gas composition when partially using natural gas as a bridge technology. This allows for an implementation in the near future as well as the possibility of supplying power grid services in a renewable energy system. Furthermore it is shown that an emission reduction potential of up to 97.8% can be achieved with a hydrogen-based process route and 99% with a syngas-based process route respectively provided that renewable electricity is used.
Challenges and Outlines of Steelmaking toward the Year 2030 and Beyond—Indian Perspective
Oct 2021
Publication
In FY-20 India’s steel production was 109 MT and it is the second-largest steel producer on the planet after China. India’s per capita consumption of steel was around 75 kg which has risen from 59 kg in FY-14. Despite the increase in consumption it is much lower than the average global consumption of 230 kg. The per capita consumption of steel is one of the strongest indicators of economic development across the nation. Thus India has an ambitious plan of increasing steel production to around 250 MT and per capita consumption to around 160 kg by the year 2030. Steel manufacturers in India can be classified based on production routes as (a) oxygen route (BF/BOF route) and (b) electric route (electric arc furnace and induction furnace). One of the major issues for manufacturers of both routes is the availability of raw materials such as iron ore direct reduced iron (DRI) and scrap. To achieve the level of 250 MT steel manufacturers have to focus on improving the current process and product scenario as well as on research and development activities. The challenge to stop global warming has forced the global steel industry to strongly cut its CO2 emissions. In the case of India this target will be extremely difficult by ruling in the production duplication planned by the year 2030. This work focuses on the recent developments of various processes and challenges associated with them. Possibilities and opportunities for improving the current processes such as top gas recycling increasing pulverized coal injection and hydrogenation as well as the implementation of new processes such as HIsarna and other CO2 -lean iron production technologies are discussed. In addition the eventual transition to hydrogen ironmaking and “green” electricity in smelting are considered. By fast-acting improvements in current facilities and brave investments in new carbon-lean technologies the CO2 emissions of the Indian steel industry can peak and turn downward toward carbon-neutral production.
Carbon-Negative Hydrogen Production (HyBECCS) from Organic Waste Materials in Germany: How to Estimate Bioenergy and Greenhouse Gas Mitigation Potential
Nov 2021
Publication
Hydrogen derived from biomass feedstock (biohydrogen) can play a significant role in Germany’s hydrogen economy. However the bioenergy potential and environmental benefits of biohydrogen production are still largely unknown. Additionally there are no uniform evaluation methods present for these emerging technologies. Therefore this paper presents a methodological approach for the evaluation of bioenergy potentials and the attainable environmental impacts of these processes in terms of their carbon footprints. A procedure for determining bioenergy potentials is presented which provides information on the amount of usable energy after conversion when applied. Therefore it elaborates a four-step methodical conduct dealing with available waste materials uncertainties of early-stage processes and calculation aspects. The bioenergy to be generated can result in carbon emission savings by substituting fossil energy carriers as well as in negative emissions by applying biohydrogen production with carbon capture and storage (HyBECCS). Hence a procedure for determining the negative emissions potential is also presented. Moreover the developed approach can also serve as a guideline for decision makers in research industry and politics and might also serve as a basis for further investigations such as implementation strategies or quantification of the benefits of biohydrogen production from organic waste material in Germany
Effect of TiO2 on Electrocatalytic Behavior of Ni-Mo Alloy Coating for Hydrogen Energy
Jun 2018
Publication
Ni-Mo-TiO2 composite coating has been developed through electrodeposition method by depositing titanium dioxide (TiO2) nanoparticles parallel to the process of Ni-Mo alloy coating. The experimental results explaining the increased electrocatalytic activity of Ni-Mo alloy coating on incorporation of TiO2 nanoparticles into its alloy matrix is reported here. The effect of addition of TiO2 on composition morphology and phase structure of TiO2 – composite coating is studied with special emphasis on its electrocatalytic activity for hydrogen evolution reaction (HER) in 1.0 M KOH solution. The electrocatalytic activity of alloy coatings were validated using cyclic voltammetry (CV) and chronopotentiometry (CP) techniques. Under optimal condition TiO2 – composite alloy coating represented as (Ni-Mo-TiO2)2.0 A dm 2 is found to exhibit the highest electrocatalytic activity for HER compared to its binary alloy counterpart. The increased electrocatalytic activity of (Ni-Mo-TiO2)2.0 A dm 2 composite coating was attributed to the increased Mo content porosity and roughness of coating affected due to addition of TiO2 nanoparticles supported by SEM EDX XRD and AFM study. The increased electrocatalytic activity of (Ni-Mo-TiO2)2.0 A dm 2 coating was found due to decreased Rct and increased Cdl values demonstrated by EIS study. Better electrocatalytic activity of (Ni-Mo-TiO2)2.0 A dm 2 coating compared to (Ni-Mo)2.0 A dm 2 coating has been explained through mechanism. Experimental study revealed that (Ni-Mo-TiO2)2.0 A dm 2 composite coating follows Volmer-Heyrovsky mechanism compared to Tafel mechanism in case of (Ni-Mo-TiO2)2.0 A dm 2 coating assessed on the basis of Tafel slopes.
Hybrid Power Management Strategy with Fuel Cell, Battery, and Supercapacitor for Fuel Economy in Hybrid Electric Vehicle Application
Jun 2022
Publication
The power management strategy (PMS) is intimately linked to the fuel economy in the hybrid electric vehicle (HEV). In this paper a hybrid power management scheme is proposed; it consists of an adaptive neuro-fuzzy inference method (ANFIS) and the equivalent consumption minimization technique (ECMS). Artificial intelligence (AI) is a key development for managing power among various energy sources. The hybrid power supply is an eco-acceptable system that includes a proton exchange membrane fuel cell (PEMFC) as a primary source and a battery bank and ultracapacitor as electric storage systems. The Haar wavelet transform method is used to calculate the stress (σ) on each energy source. The proposed model is developed in MATLAB/Simulink software. The simulation results show that the proposed scheme meets the power demand of a typical driving cycle i.e. Highway Fuel Economy Test Cycle (HWFET) and Worldwide Harmonized Light Vehicles Test Procedures (WLTP—Class 3) for testing the vehicle performance and assessment has been carried out for various PMS based on the consumption of hydrogen overall efficiency state of charge of ultracapacitors and batteries stress on hybrid sources and stability of the DC bus. By combining ANFIS and ECMS the consumption of hydrogen is minimized by 8.7% compared to the proportional integral (PI) state machine control (SMC) frequency decoupling fuzzy logic control (FDFLC) equivalent consumption minimization strategy (ECMS) and external energy minimization strategy (EEMS).
Pt Catalytic Effects on the Corrosion and Hydrogen Chemisorption Properties of Zircaloy-2
Dec 2020
Publication
Noble metals are added to boiling water reactors (BWRs) to mitigate stress corrosion cracking of structural components made from steels and Ni-based alloys and this technology is referred to as Noble Metal Chemical Addition (NMCA) or NobleChemTM. There is a growing concern that NMCA can cause unwanted harmful effects on the corrosion and hydrogen uptake properties of Zircaloy-2 fuel cladding. To investigate this we have subjected Zircaloy-2 fuel claddings to out-of-pile BWR conditions in a custom-built autoclave. These claddings are oxidized in pressurized hot water (280 °C 9 MPa) for 25 60 and 150 days wherein Pt nanoparticles (~10 nm) were simultaneously injected. Cross-sectional focused ion beam cuts made at the oxide-metal interface reveal that the oxide growth is not significantly influenced by the local Pt loadings (≤ 1 µg·cm-2). Surprisingly an inverse correlation was observed between oxide thicknesses and metal's hydrogen contents. Interestingly Pt catalysts have led to diminished hydrogen absorption in specimens with liner exposed to the hot water. Overall Pt catalysts exhibited no detrimental effects on the corrosion rate and hydrogen absorption in Zircaloy-2.
Structural Model of Power Grid Stabilization in the Green Hydrogen Supply Chain System—Conceptual Assumptions
Jan 2022
Publication
The paper presents the conceptual assumptions of research concerning the design of a theoretical multi-criteria model of a system architecture to stabilize the operation of power distribution networks based on a hydrogen energy buffer taking into account the utility application of hydrogen. The basis of the research process was a systematic literature review using the technique of in-depth analysis of full-text articles and expert consultations. The structural model concept was described in two dimensions in which the identified variables were embedded. The first dimension includes the supply chain phases: procurement and production with warehousing and distribution. The second dimension takes into account a comprehensive and interdisciplinary approach and includes the following factors: technical economic–logistical locational and formal–legal.
Microfluidics-based Analysis of Dynamic Contact Angles Relevant for Underground Hydrogen Storage
May 2022
Publication
Underground Hydrogen Storage (UHS) is an attractive technology for large-scale (TWh) renewable energy storage. To ensure the safety and efficiency of the UHS it is crucial to quantify the H2 interactions with the reservoir fluids and rocks across scales including the micro scale. This paper reports the experimental measurements of advancing and receding contact angles for different channel widths for a H2 /water system at P = 10 bar and T = 20 ◦C using a microfluidic chip. To analyse the characteristics of the H2 flow in straight pore throats the network is designed such that it holds several straight channels. More specifically the width of the microchannels range between 50 μm and 130 μm. For the drainage experiments H2 is injected into a fully water saturated system while for the imbibition tests water is injected into a fully H2 -saturated system. For both scenarios high-resolution images are captured starting the introduction of the new phase into the system allowing for fully-dynamic transport analyses. For better insights N2 /water and CO2 /water flows were also analysed and compared with H2 /water. Results indicate strong water-wet conditions with H2 /water advancing and receding contact angles of respectively 13◦–39◦ and 6◦–23◦ . It was found that the contact angles decrease with increasing channel widths. The receding contact angle measured in the 50 μm channel agrees well with the results presented in the literature by conducting a core-flood test for a sandstone rock. Furthermore the N2 /water and CO2 /water systems showed similar characteristics as the H2 /water system. In addition to the important characterization of the dynamic wettability the results are also crucially important for accurate construction of pore-scale simulators.
The Role of the Flow Field Generated by Venting Process on the Pressure Time History of a Vented Deflagration
Sep 2017
Publication
Vented deflagrations are one of the most challenging phenomenon to be replicated numerically in order to predict its resulting pressure time history. As a matter of fact a number of different phenomena can contribute to modify the burning velocity of a gas mixture undergoing a deflagration especially when the flame velocity is considerably lower than the speed of sound. In these conditions acceleration generated by both the flow field induced by the expanding flame and from discontinuities as the vent opening and the venting of the combustion products affect the burning velocity and the burning behaviour of the flame. In particular the phenomena affecting the pressure time history of a deflagration after the flame front reaches the vent area such as flame acoustic interaction and local pressure peaks seem to be closely related to a change in the burning behaviour induced by the venting process. Flame acoustic interaction and local pressure peaks arise as a consequence of the change in the burning behaviour of the flame. This paper analyses the video recording of the flame front produced during the TP experimental campaign performed by UNIPI in the project HySEA to analyse qualitatively the contribution of the generated flow field in a vented deflagration in its pressure-time history.
HyDeploy2: Materials Summary and Interpretation
May 2021
Publication
During the exemption application process the original report was evaluated as part of a regulatory review and responses to questions submitted for further consideration. These have been addressed in this revised version (revision 1) in the form of an addendum. The addendum includes the question raised its number and the response to it. The area of the main body of the report to which each question and response refers is indicated by square brackets and the addendum number e.g. [A1].<br/>Through analysis of the literature and results of the practical testing the susceptibility of materials present in the Winlaton trial site to hydrogen degradation has been assessed with consideration of the Winlaton operating conditions (up to 20% H2 at total blend pressures of 20 mbar – 2 bar). The aim of this report has been to determine whether there are any components which have been identified at the Winlaton trial site which could have a significantly increased risk of failure due to their exposure to hydrogen during the one year trial. Where possible direct supporting data has been used to make assessments on the likelihood of failure; in other cases the assessment was aided by collaborative expert opinion in the fields of mechanical engineering materials science and the domestic gas industry.<br/>Click on the supplements tab to view the other documents from this report
Optimization of Energy Management Strategy for Fuel Cell Hybrid Electric Vehicles Based on Dynamic Programming
Jun 2022
Publication
Fuel cell hybrid electric vehicles have attracted a large amount of attention in recent years owing to their advantages of zero emissions high efficiency and low noise. To improve the fuel economy and system durability of vehicles this paper proposes an energy management strategy optimization method for fuel cell hybrid electric vehicles based on dynamic programming. Rule-based and dynamic-programming-based strategies are developed based on building a fuel cell/battery hybrid system model. The rule-based strategy is improved with a power distribution scheme of dynamic programming strategy to improve the fuel economy of the vehicle. Furthermore a limit on the rate of change of the output power of the fuel cell system is added to the rule-based strategy to avoid large load changes to improve the durability of the fuel cell. The simulation results show that the equivalent 100 km hydrogen consumption of the strategy based on the dynamic programming optimization rules is reduced by 6.46% compared with that before the improvement and by limiting the rate of change of the output power of the fuel cell system the times of large load changes are reduced. Therefore the strategy based on the dynamic programming optimization rules effectively improves the fuel economy and system durability of vehicles.
Everything About Hydrogen Podcast: Building Europe's Hydrogen Mobility Network
Jan 2020
Publication
On this weeks episode the team are talking all things hydrogen with Jacob Krogsgaard the CEO of Everfuel a leading supplier of green hydrogen for mobility and industry in Europe. Since its establishment by Nel and a Consortium of parties and investors Everfuel has become a market leader in establishing green hydrogen solutions for mobility in Europe and has recently expanded into areas such as power-to-gas as well. The team catch up with Jacob on Everfuels business model the establishment of the H2Bus Consortium Jacob’s views on how the market for green hydrogen is evolving in Europe and where he sees the greatest early potential for scaling.…..All this and more on the show!
The podcast can be found on their website
The podcast can be found on their website
Hydrogen for Net Zero - A Critical Cost-competitive Energy Vector
Nov 2021
Publication
The report “Hydrogen for Net Zero” presents an ambitious yet realistic deployment scenario until 2030 and 2050 to achieve Net Zero emissions considering the uses of hydrogen in industry power mobility and buildings. The scenario is described in terms of hydrogen demand supply infrastructure abatement potential and investments required and then compared with current momentum and investments in the industry to identify the investment gaps across value chains and geographies.
The report is based on the technoeconomic data of cost and performance of hydrogen technologies provided by Hydrogen Council members and McKinsey & Company as well as the Hydrogen Council investment tracker which covers all large-scale investments into hydrogen globally.
Link to their website
The report is based on the technoeconomic data of cost and performance of hydrogen technologies provided by Hydrogen Council members and McKinsey & Company as well as the Hydrogen Council investment tracker which covers all large-scale investments into hydrogen globally.
Link to their website
A Review of Heavy-Duty Vehicle Powertrain Technologies Diesel Engine Vehicles, Battery Electric Vehicles, and Hydrogen Fuel Cell Electric Vehicles
Jun 2021
Publication
Greenhouse gas emissions from the freight transportation sector are a significant contributor to climate change pollution and negative health impacts because of the common use of heavy-duty diesel vehicles (HDVs). Governments around the world are working to transition away from diesel HDVs and to electric HDVs to reduce emissions. Battery electric HDVs and hydrogen fuel cell HDVs are two available alternatives to diesel engines. Each diesel engine HDV battery-electric HDV and hydrogen fuel cell HDV powertrain has its own advantages and disadvantages. This work provides a comprehensive review to examine the working mechanism performance metrics and recent developments of the aforementioned HDV powertrain technologies. A detailed comparison between the three powertrain technologies highlighting the advantages and disadvantages of each is also presented along with future perspectives of the HDV sector. Overall diesel engine in HDVs will remain an important technology in the short-term future due to the existing infrastructure and lower costs despite their high emissions while battery-electric HDV technology and hydrogen fuel cell HDV technology will be slowly developed to eliminate their barriers including costs infrastructure and performance limitations to penetrate the HDV market.
Direct Evidence for Solid-like Hydrogen in a Nanoporous Carbon Hydrogen Storage Material at Supercritical Temperatures
Jul 2015
Publication
Here we report direct physical evidence that confinement of molecular hydrogen (H2) in an optimized nanoporous carbon results in accumulation of hydrogen with characteristics commensurate with solid H2 at temperatures up to 67 K above the liquid vapor critical temperature of bulk H2. This extreme densification is attributed to confinement of H2 molecules in the optimally sized micropores and occurs at pressures as low as 0.02 MPa. The quantities of contained solid-like H2 increased with pressure and were directly evaluated using in situ inelastic neutron scattering and confirmed by analysis of gas sorption isotherms. The demonstration of the existence of solid-like H2 challenges the existing assumption that supercritical hydrogen confined in nanopores has an upper limit of liquid H2 density. Thus this insight offers opportunities for the development of more accurate models for the evaluation and design of nanoporous materials for high capacity adsorptive hydrogen storage.
Cost-optimized Design Point and Operating Strategy of Polymer Electrolyte Membrane Electrolyzers
Nov 2022
Publication
Green hydrogen is a key solution for reducing CO2 emissions in various industrial applications but high production costs continue to hinder its market penetration today. Better competitiveness is linked to lower investment costs and higher efficiency of the conversion technologies among which polymer electrolyte membrane electrolysis seems to be attractive. Although new manufacturing techniques and materials can help achieve these goals a less frequently investigated approach is the optimization of the design point and operating strategy of electrolyzers. This means in particular that the questions of how often a system should be operated and which cell voltage should be applied must be answered. As existing techno-economic models feature gaps which means that these questions cannot be adequately answered a modified model is introduced here. In this model different technical parameters are implemented and correlated to each other in order to simulate the lowest possible levelized cost of hydrogen and extract the required designs and strategies from this. In each case investigated the recommended cost-based cell voltage that should be applied to the system is surprisingly low compared to the assumptions made in previous publications. Depending on the case the cell voltage is in a range between 1.6 V and 1.8 V with an annual operation of 2000e8000 h. The wide range of results clearly indicate how individual the design and operation must be but with efficiency gains of several percent the effect of optimization will be indispensable in the future.
Design and Optimization of Coal to Hydrogen System Coupled with Non-Nominal Operation of Thermal Power Unit
Dec 2022
Publication
In an actual thermal power plant deep peak shaving will cause thermal power units to run under non-nominal conditions for an extended period resulting in serious problems such as increased equipment wearing low equipment utilization efficiency and decreased benefits. To this end in this work both the design and optimization method for a coal to hydrogen system which is coupled with the expected non-nominal operation of thermal power units are proposed. Aiming towards maximum profit in the context of thermal power plants a mathematical optimization model for a coal to hydrogen system based on the multi-period operating conditions of thermal power plants is established. The corresponding optimal design scheme of the coal to hydrogen system is determined using variable operating conditions. The superiority of the integrated system compared with an independent system is explored and the feasibility of the proposed method is verified by using the case study of an actual thermal power plant. The results show that compared with the independent system the economic benefits of the integrated system can increase by 13.56% where the sale of hydrogen in the coal to hydrogen system accounts for 60.3% of the total benefit. The main expenditure associated with the system is the purchase cost of feedstock coal accounting for 91.8%. Since the required power and medium-pressure steam in the coal to hydrogen process are provided by thermal power units the minimum operating load of the thermal power plant in the integrated system increases from 40% to 60.1% which significantly improves the utilization efficiency and service life of the generator units. In addition the proposed integration scheme of the system is simple and controllable which can contribute to the maintenance of the safe and stable operation of power generation and hydrogen production processes. These results are expected to provide the necessary methodological guidance for the integration and optimization of coal-fired power plants and coal to hydrogen systems.
Model Predictive Control of an Off-sire Green Hydrogen Production and Refuelling Station
Jan 2023
Publication
The expected increase of hydrogen fuel cell vehicles has motivated the emergence of a significant number of studies on Hydrogen Refuelling Stations (HRS). Some of the main HRS topics are sizing location design optimization and optimal operation. On-site green HRS where hydrogen is produced locally from green renewable energy sources have received special attention due to their contribution to decarbonization. This kind of HRS are complex systems whose hydraulic and electric linked topologies include renewable energy sources electrolyzers buffer hydrogen tanks compressors and batteries among other components. This paper develops a linear model of a real on-site green HRS that is set to be built in Zaragoza Spain. This plant can produce hydrogen either from solar energy or from the utility grid and is designed for three different types of services: light-duty and heavy-duty fuel cell vehicles and gas containers. In the literature there is a lack of online control solutions developed for HRS even more in the form of optimal online control. Hence for the HRS operation a Model Predictive Controller (MPC) is designed to solve a weighted multi-objective online optimization problem taking into account the plant dynamics and constraints as well as the disturbances prediction. Performance is analysed throughout 210 individual month-long simulations and the effect of the multi-objective weighting prediction horizon and hydrogen selling price is discussed. With the simulation results this work shows the suitability of MPC for HRS control and its significant economic advantage compared to the rule-based control solution. In all simulations the MPC operation fulfils all required services. Moreover results show that a seven-day prediction horizon can improve profits by 57% relative to a one-day prediction horizon; that the battery is under-sized; or that the MPC operation strategy is more resolutive for low hydrogen selling prices.
A Zero Carbon Route to the Supply of High-temperature Heat Through the Integration of Solid Oxide Electrolysis Cells and H2–O2 Combustion
Aug 2022
Publication
Previously suggested options to achieve carbon neutrality involve the use of fossil fuels with carbon capture or exploiting biomass as sources of energy. Industrial high-temperature heating could possibly exploit electrical heating or combustion using hydrogen. However it is difficult to replace all the current coal or natural gas furnaces with these options for chemical industry. In this work a method that integrates solid oxide electrolysis cells (SOEC) and H2–O2 combustion is proposed and the related parameters are modelled to analyze their impacts. There is no waste heat and waste emissions in the proposed option and all substances are recycled. Unlike previous research the heat required for SOEC operation is generated from H2 combustion. The best working condition is under thermoneutral voltage and the highest electricity-to-thermal efficiency that can be achieved is 86.88% under a current density of 12000 A/m2 and operating temperature of 750 ◦C. Ohmic overpotential has the greatest effect on electricity consumption and the anode activation overpotential is the second most important option. Increasing combustion product temperature cannot significantly improve thermal efficiency but can raise the available maximum thermal energy.
Influence of Air Distribution on Combustion Characteristics of a Micro Gas Turbine Fuelled by Hydrogen-doped Methane
Nov 2021
Publication
Adding hydrogen to the fuel can change the combustion characteristics and greatly improve the pollutants emission for the gas turbine. The numerical method was adopted to study the combustion process in a counter-flow combustor of a 100 kW micro gas turbine using methane doped by hydrogen and various distribution schemes of air flow. The combustion characteristics and pollutant emissions were explored to ascertain the influence of air distribution based on solving the validated models. It was shown that as the amount of premixed air increased in the swirling gas the range of the recirculation region became larger and the range of the high-temperature zone in the combustion chamber gradually enlarged. When the amount of premixed air was 30% the outlet temperature distribution of the combustor was excellent and the average temperature was 1172 K. Moreover the concentration of NOX gradually increased and reached a maximum value of 23.46 ppm (@15% O2) as the premixed air increased in the range of the ratio less than 40%. It was reduced to 0.717 ppm (@15% O2) when the amount of premixed air increased to 50%. These findings may support the running of the micro gas turbine using the hybrid fuel of hydrogen and methane.
Techno-economic Assessment of a Hydrogen-based Islanded Microgrid in North-east
Feb 2023
Publication
Currently renewable energy-based generators are considered worldwide to achieve net zero targets. However the stochastic nature of renewable energy systems leads to regulation and control challenges for power system operators especially in remote and regional grids with smaller footprints. A hybrid system (i.e. solar wind biomass energy storage) could minimise this issue. Nevertheless the hybrid system is not possible to develop in many islands due to the limited land area geographical conditions and others. Hydrogen as a carrier of clean energy can be used in locations where the installation of extensive or medium-scale renewable energy facilities is not permissible due to population density geographical constraints government policies and regulatory issues. This paper presents a techno-economic assessment of designing a green hydrogen-based microgrid for a remote island in North-east Australia. This research work determines the optimal sizing of microgrid components using green hydrogen technology. Due to the abovementioned constraints the green hydrogen production system and the microgrid proposed in this paper are located on two separate islands. The paper demonstrates three cost-effective scenarios for green hydrogen production transportation and electricity generation. This work has been done using Hybrid Optimisation Model for Multiple Energy Resources or HOMER Pro simulation platform. Simulation results show that the Levelized Cost of Energy using hydrogen technology can vary from AU$0.37/kWh to AU$1.08/kWh depending on the scenarios and the variation of key parameters. This offers the potential to provide lower-cost electricity to the remote community. Furthermore the CO2 emission could be reduced by 1760777 kg/year if the renewable energy system meets 100% of the electricity demand. Additionally the sensitivity analysis in this paper shows that the size of solar PV and wind used for green hydrogen production can further be reduced by 50%. The sensitivity analysis shows that the system could experience AU$0.03/kWh lower levelized cost if the undersea cable is used to transfer the generated electricity between islands instead of hydrogen transportation. However it would require environmental approval and policy changes as the islands are located in the Great Barrier Reef.
Hydrogen Storage by Liquid Hydrogen Carriers: Catalyst, Renewable Carrier, and Technology - A Review
Mar 2023
Publication
Hydrogen has attracted widespread attention as a carbon-neutral energy source but developing efficient and safe hydrogen storage technologies remains a huge challenge. Recently liquid organic hydrogen carriers (LOHCs) technology has shown great potential for efficient and stable hydrogen storage and transport. This technology allows for safe and economical large-scale transoceanic transportation and long-cycle hydrogen storage. In particular traditional organic hydrogen storage liquids are derived from nonrenewable fossil fuels through costly refining procedures resulting in unavoidable environmental contamination. Biomass holds great promise for the preparation of LOHCs due to its unique carbon-balance properties and feasibility to manufacture aromatic and nitrogen-doped compounds. According to recent studies almost 100% conversion and 92% yield of benzene could be obtained through advanced biomass conversion technologies showing great potential in preparing biomass-based LOHCs. Overall the present LOHCs systems and their unique applications are introduced in this review and the technical paths are summarized. Furthermore this paper provides an outlook on the future development of LOHCs technology focusing on biomass-derived aromatic and N-doped compounds and their applications in hydrogen storage.
Determinants of Consumers’ Purchasing Intentions for the Hydrogen-Electric Motorcycle
Aug 2017
Publication
In recent years increasing concerns regarding the energy costs and environmental effects of urban motorcycle use have spurred the development of hydrogen-electric motorcycles in Taiwan. Although gasoline-powered motorcycles produce substantial amounts of exhaust and noise pollution hydrogen-electric motorcycles are highly energy-efficient relatively quiet and produce zero emissions features that suggest their great potential to reduce the problems currently associated with the use of motorcycles in city environments. This study identified the significant external variables that affect consumers’ purchase intentions toward using hydrogen-electric motorcycles. A questionnaire method was employed with a total of 300 questionnaires distributed and 233 usable questionnaires returned yielding a 78% overall response rate. Structural equation modeling (SEM) was applied to test the research hypothesis. The research concluded that (1) product knowledge positively influenced purchase intentions but negatively affected the perceived risk; (2) perceived quality via hydrogen-electric motorcycles positively influenced the perceived value but negatively affected the perceived risk; (3) perceived risk negatively affected the perceived value; and (4) the perceived value positively affected purchase intentions. This study can be used as a reference for motorcycle manufacturers when planning their marketing strategies.
Interlinking the Renewable Electricity and Gas Sectors: A Techno-Economic Case Study for Austria
Oct 2021
Publication
Achieving climate neutrality requires a massive transformation of current energy systems. Fossil energy sources must be replaced with renewable ones. Renewable energy sources with reasonable potential such as photovoltaics or wind power provide electricity. However since chemical energy carriers are essential for various sectors and applications the need for renewable gases comes more and more into focus. This paper determines the Austrian green hydrogen potential produced exclusively from electricity surpluses. In combination with assumed sustainable methane production the resulting renewable gas import demand is identified based on two fully decarbonised scenarios for the investigated years 2030 2040 and 2050. While in one scenario energy efficiency is maximised in the other scenario significant behavioural changes are considered to reduce the total energy consumption. A techno-economic analysis is used to identify the economically reasonable national green hydrogen potential and to calculate the averaged levelised cost of hydrogen (LCOH2) for each scenario and considered year. Furthermore roll-out curves for the necessary expansion of national electrolysis plants are presented. The results show that in 2050 about 43% of the national gas demand can be produced nationally and economically (34 TWh green hydrogen 16 TWh sustainable methane). The resulting national hydrogen production costs are comparable to the expected import costs (including transport costs). The most important actions are the quick and extensive expansion of renewables and electrolysis plants both nationally and internationally
The Role of Hydrogen in a Greenhouse Gas-neutral Energy Supply System in Germany
Sep 2022
Publication
Hydrogen is widely considered to play a pivotal role in successfully transforming the German energy system but the German government’s current “National Hydrogen Strategy” does not specify how hydrogen utilization production storage or distribution will be implemented. Addressing key uncertainties for the German energy system’s path to greenhouse gas-neutrality this paper examines hydrogen in different scenarios. This analysis aims to support the concretization of the German hydrogen strategy. Applying a European energy supply model with strong interactions between the conversion sector and the hydrogen system the analysis focuses on the requirements for geological hydrogen storages and their utilization over the course of a year the positioning of electrolyzers within Germany and the contributions of hydrogen transport networks to balancing supply and demand. Regarding seasonal hydrogen storages the results show that hydrogen storage facilities in the range of 42 TWhH2 to 104 TWhH2 are beneficial to shift high electricity generation volumes from onshore wind in spring and fall to winter periods with lower renewable supply and increased electricity and heat demands. In 2050 the scenario results show electrolyzer capacities between 41 GWel and 75 GWel in Germany. Electrolyzer sites were found to follow the low-cost renewable energy potential and are concentrated on the North Sea and Baltic Sea coasts with their high wind yields. With respect to a hydrogen transport infrastructure there were two robust findings: One a domestic German hydrogen transport network connecting electrolytic hydrogen production sites in northern Germany with hydrogen demand hubs in western and southern Germany is economically efficient. Two connecting Germany to a European hydrogen transport network with interconnection capacities between 18 GWH2 and 58 GWH2 is cost-efficient to meet Germany’s substantial hydrogen demand.
Residual Tensile Properties of Carbon Fiber Reinforced Epoxy Resin Composites at Elevated Temperatures
Sep 2021
Publication
Carbon fiber reinforced epoxy resin composites have attracted great attention in high pressure hydrogen storage for its light weight and excellent mechanical properties. The degradation of residual mechanical properties at elevated temperature from 20 °C to 450 °C were studied experimentally. The effects of temperature on the tensile strength and failure mode of the composite specimens with stacking sequences of 0° 90° and ±45° (labeled as CF0 CF90 and CF 45) were systematically analyzed followed by the fracture surfaces examination. Results show that the tensile strength residual ratios of the three kinds of specimens decrease significantly with heating temperature increasing. In particular the decomposing temperature of the resin matrix exerts the largest effects on the degradation of tensile strength of CF0 specimen within 450 °C. While the loss of tensile strength of CF90 and CF45 specimens is dependent on the thermal softening of epoxy resin which has closely related to the glass transition temperature. Furthermore the debonding and fiber softening appeared in the CF0 specimens when the temperature reached 450 °C. For CF90 specimens the degradation of bonding strength of epoxy could be found at 150 °C and regarding CF45 specimens delamination cracking between plies occurred extensively when the temperature above 125 °C.
Techno-economic Assessment of Offshore Wind-to-hydrogen Scenarios: A UK Case Study
Jan 2023
Publication
The installed capacity electricity generation from wind and the curtailment of wind power in the UK between 2011 and 2021 showed that penetration levels of wind energy and the amount of energy that is curtailed in future would continue to rise whereas the curtailed energy could be utilised to produce green hydrogen. In this study data were collected technologies were chosen systems were designed and simulation models were developed to determine technical requirements and levelised costs of hydrogen produced and transported through different pathways. The analysis of capital and operating costs of the main components used for onshore and offshore green hydrogen production using offshore wind including alternative strategies for hydrogen storage and transport and hydrogen carriers showed that a significant reduction in cost could be achieved by 2030 enabling the production of green hydrogen from offshore wind at a competitive cost compared to grey and blue hydrogen. Among all scenarios investigated in this study compressed hydrogen produced offshore is the most cost-effective scenario for projects starting in 2025 although the economic feasibility of this scenario is strongly affected by the storage period and the distance to the shore of the offshore wind farm. Alternative scenarios for hydrogen storage and transport such as liquefied hydrogen and methylcyclohexane could become more cost-effective for projects starting in 2050 when the levelised cost of hydrogen could reach values of about £2 per kilogram of hydrogen or lower.
A Numerical Investigation on De-NOx Technology and Abnormal Combustion Control for a Hydrogen Engine with EGR System
Sep 2020
Publication
The combustion emissions of the hydrogen-fueled engines are very clean but the problems of abnormal combustion and high NOx emissions limit their applications. Nowadays hydrogen engines use exhaust gas recirculation (EGR) technology to control the intensity of premixed combustion and reduce the NOx emissions. This study aims at improving the abnormal combustion and decreasing the NOx emissions of the hydrogen engine by applying a three-dimensional (3D) computational fluid dynamics (CFD) model of a single-cylinder hydrogen-fueled engine equipped with an EGR system. The results indicated that peak in-cylinder pressure continuously increased with the increase of the ignition advance angle and was closer to the top dead center (TDC). In addition the mixture was burned violently near the theoretical air–fuel ratio and the combustion duration was shortened. Moreover the NOx emissions the average pressure and the in-cylinder temperature decreased as the EGR ratio increased. Furthermore increasing the EGR ratio led to an increase in the combustion duration and a decrease in the peak heat release rate. EGR system could delay the spontaneous combustion reaction of the end-gas and reduce the probability of knocking. The pressure rise rate was controlled and the in-cylinder hot spots were reduced by the EGR system which could suppress the occurrence of the pre-ignition in the hydrogen engine.
Methodologies for Representing the Road Transport Sector in Energy System Models
Dec 2013
Publication
Energy system models are often used to assess the potential role of hydrogen and electric powertrains for reducing transport CO2 emissions in the future. In this paper we review how different energy system models have represented both vehicles and fuel infrastructure in the past and we provide guidelines for their representation in the future. In particular we identify three key modelling decisions: the degree of car market segmentation the imposition of market share constraints and the use of lumpy investments to represent infrastructure. We examine each of these decisions in a case study using the UK MARKAL model. While disaggregating the car market principally affects only the transition rate to the optimum mix of technologies market share constraints can greatly change the optimum mix so should be chosen carefully. In contrast modelling infrastructure using lumpy investments has little impact on the model results. We identify the development of new methodologies to represent the impact of behavioural change on transport demand as a key challenge for improving energy system models in the future.
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