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Irreproducibility in Hydrogen Storage Material Research
Sep 2016
Publication
The storage of hydrogen in materials has received a significant amount of attention in recent years because this approach is widely thought to be one of the most promising solutions to the problem of storing hydrogen for use as an alternative energy carrier in a safe compact and affordable form. However there have been a number of high profile cases in which erroneous or irreproducible data have been published. Meanwhile the irreproducibility of research results in a wide range of disciplines has been the subject of an increasing amount of attention due to problems with some of the data in the literature. In this Perspective we provide a summary of the problems that have affected hydrogen storage material research. We also discuss the reasons behind them and possible ways of reducing the likelihood of further problems occurring in the future.
Decarbonising Ships, Planes and Trucks: An Analysis of Suitable Low-carbon Fuels for the Maritime, Aviation and Haulage Sectors
Jan 2021
Publication
The high environmental impacts of transport mean that there is an increasing interest in utilising low-carbon alternative energy carriers and powertrains within the sector. While electricity has been mooted as the energy carrier of choice for passenger vehicles as the mass and range of the vehicle increases electrification becomes more difficult. This paper reviews the shipping aviation and haulage sectors and a range of low-carbon energy carriers (electricity biofuels hydrogen and electro fuels) that can be used to decarbonise them. Energy carriers were assessed based on their energy density specific energy cost lifecycle greenhouse gas emissions and land-use. In terms of haulage current battery electric vehicles may be technically feasible however the specific energy of current battery technology reduces the payload capacity and range when compared to diesel. To alleviate these issues biomethane represents a mature technology with potential co-benefits while hydrogen is close to competitiveness but requires significant infrastructure. Energy density issues preclude the use of batteries in shipping which requires energy dense liquids or compressed gaseous fuels that allow for retrofits/current hull designs with methanol being particularly appropriate here. Future shipping may be achieved with ammonia or hydrogen but hull design will need to be changed significantly. Regulations and aircraft design mean that commercial aviation is dependant on drop-in jet fuels for the foreseeable future with power-to-liquid fuels being deemed the most suitable option due to the scales required. Fuel costs and a lack of refuelling infrastructure were identified as key barriers facing the uptake of alternatives with policy and financial incentives required to encourage the uptake of low-carbon fuels.
Health and safety in the new energy economy
Dec 2010
Publication
Over the next decade and beyond the UK is set to take significant steps towards a new energy economy. This will be an economy where the technologies meeting<br/>our electricity heat and fuel needs have to deliver against three key criteria: sustainability security and affordability.<br/><br/>In this context a wide range of emerging energy technologies are expected to play an important role in reshaping the way we satisfy our energy requirements. The extent to which they do so however will depend fundamentally on their ability to be harnessed safely.<br/><br/>Compiled by HSE’s Emerging Energy Technologies Programme this report provides a current assessment of the health and safety hazards that key emerging energy technologies could pose both to workers and to the public at large. (Nuclear energy technologies fall outside the scope of this report.) But it also highlights how an appropriate framework can be and is being put in place to help ensure that these hazards are managed and controlled effectively – an essential<br/>element in enabling the technologies to make a major contribution to the UK’s energy future.
Recent Developments in Carbon-Based Nanocomposites for Fuel Cell Applications: A Review
Jan 2022
Publication
Carbon-based nanocomposites have developed as the most promising and emerging materials in nanoscience and technology during the last several years. They are microscopic materials that range in size from 1 to 100 nanometers. They may be distinguished from bulk materials by their size shape increased surface-to-volume ratio and unique physical and chemical characteristics. Carbon nanocomposite matrixes are often created by combining more than two distinct solid phase types. The nanocomposites that were constructed exhibit unique properties such as significantly enhanced toughness mechanical strength and thermal/electrochemical conductivity. As a result of these advantages nanocomposites have been used in a variety of applications including catalysts electrochemical sensors biosensors and energy storage devices among others. This study focuses on the usage of several forms of carbon nanomaterials such as carbon aerogels carbon nanofibers graphene carbon nanotubes and fullerenes in the development of hydrogen fuel cells. These fuel cells have been successfully employed in numerous commercial sectors in recent years notably in the car industry due to their cost-effectiveness eco-friendliness and long-cyclic durability. Further; we discuss the principles reaction mechanisms and cyclic stability of the fuel cells and also new strategies and future challenges related to the development of viable fuel cells.
Indoor Use of Hydrogen, Knowledge Gaps and Priorities for the Improvement of Current Standards on Hydrogen, a Presentation of HyIndoor European Project
Sep 2013
Publication
To develop safety strategies for the use of hydrogen indoors the HyIndoor project is studying the behaviour of a hydrogen release deflagration or non-premixed flame in an enclosed space such as a fuel cell or its cabinet a room or a warehouse. The paper proposes a safety approach based on safety objectives that can be used to take various scenarios of hydrogen leaks into account for the safe design of Hydrogen and Fuel Cell (HFC) early market applications. Knowledge gaps on current engineering models and unknown influence of specific parameters were identified and prioritized thereby re-focusing the objectives of the project test campaign and numerical simulations. This approach will enable the improvement of the specification of openings and use of hydrogen sensors for enclosed spaces. The results will be disseminated to all stakeholders including hydrogen industry and RCS bodies.
Effect of Rotation on Ignition Thresholds of Stoichiometric Hydrogen Mixtures
Sep 2017
Publication
Successful transition to a hydrogen economy calls for a deep understanding of the risks associated with its widespread use. Accidental ignition of hydrogen by hot surfaces is one of such risks. In the present study we investigated the effect that rotation has on the reported ignition thresholds by numerically determining the minimum surface temperature required to ignite stoichiometric hydrogen-air using a hot horizontal cylinder rotating at various angular velocities ω. Numerical experiments showed a weak but interesting dependence of the ignition thresholds on rotation: the ignition thresholds increased by 8 K from 931 K to 939 K with increasing angular velocity (0 ≤ ω ≤ 240 rad/s). A further increase to ω = 480 rad/s resulted in a decrease in ignition surface temperature to 935 K. Detailed analysis of the flow patterns inside the vessel and in close proximity to the hot surface brought about by the combined effect of buoyancy and rotation as well as of the distribution of the wall heat flux along the circumference of the cylinder support our previous findings in which regions where temperature gradients are small were found to be prone to ignition.
Regulations, Codes, and Standards (RCS) for Multi-fuel Motor Vehicle Dispensing Station
Sep 2017
Publication
In the United States requirements for liquid motor vehicle fuelling stations have been in place for many years. Requirements for motor vehicle fuelling stations for gaseous fuels including hydrogen are relatively new. These requirements have in the United States been developed along different code and standards paths. The liquid fuels have been addressed in a single document and the gaseous fuels have been addressed in documents specific to an individual gas. The result of these parallel processes is that multi-fuel stations are subject to requirements in several fuelling regulations codes and standards (RCS). This paper describes a configuration of a multi-fuel motor vehicle fuelling station and provides a detailed breakdown of the codes and standards requirements. The multi-fuel station would dispense what the U.S. Department of Energy defines as the six key alternative fuels: biodiesel electricity ethanol hydrogen natural gas and propane. The paper will also identify any apparent gaps in RCS and potential research projects that could help fill these gaps.
Reversible Ammonia-based and Liquid Organic Hydrogen Carriers for High-density Hydrogen Storage: Recent Progress
Feb 2019
Publication
Liquid hydrogen carriers are considered to be attractive hydrogen storage options because of their ease of integration into existing chemical transportation infrastructures when compared with liquid or compressed hydrogen. The development of such carriers forms part of the work of the International Energy Agency Task 32: Hydrogen-Based Energy Storage. Here we report the state-of-the-art for ammonia-based and liquid organic hydrogen carriers with a particular focus on the challenge of ensuring easily regenerable high-density hydrogen storage.
Effectiveness Evaluation of Facilities Protecting from Hydrogen-air Explosion Overpressure
Sep 2011
Publication
The physical processes of the explosion of the hydrogen cloud which is formed as a result of the instantaneous destruction of high-pressure cylinder in the fuelling station are investigated. To simulate the formation of hydrogen-air mixture and its combustion a three-dimensional model of an instantaneous explosion of the gas mixture based on the Euler equations supplemented by the conservation laws of mixture components solved by Godunov method is used. To reduce the influence of the overpressure effects in the shock wave on the surrounding environment it is proposed to use a number of protective measures. An estimation of the efficiency of safety devices is carried out by monitoring the overpressure changes in several critical points. To reduce the pressure load on the construction of protective devices a range of constructive measures is also offered.
Safety Concept of a self-sustaining PEM Hydrogen Electrolyzer System
Sep 2013
Publication
Sustainable electricity generation is gaining importance across the globe against the backdrop of ever- diminishing resources and to achieve significant reductions in CO2 emissions. One of the challenges is storing excess energy generated from wind and solar power. Siemens developed an electrolysis system based on proton exchange membrane (PEM) technology enabling large volumes of energy to be stored through the conversion of electrical energy into hydrogen. In developing this new product range Siemens worked intensively on safe operation with a special focus on safety measures (primary secondary and tertiary). Indeed hydrogen is not only a rapidly diffusing gas with a wide range of flammability but frequent lack of information leads to insecurity among the public. Siemens PEM water electrolyzer operates at a working pressure of 50 bar / 5 MPa. The current product generation is being used for demonstration purposes and fits into a 30 ft. / 9.14 m container. Further industrialized product lines up to double-digit medium voltage ranges will be available on the market short- and mid-term. The system is designed to operate self-sustaining. Therefore special features such as back-up and fail-safe mode supported by remote monitoring and access have been implemented. This paper includes Siemens' approach to develop and implement a safety concept for the PEM water electrolyzer leading into the approval and certification by a Notified Body as well as the lessons learnt from test stand and field experience in this new application field
Improved Overall Hydrogen Storage Properties of a CsH and KH Co-doped Mg(NH2)2/2LiH System by Forming Mixed Amides of Li–K and Cs–Mg
Jun 2017
Publication
A CsH and KH co-doped Mg(NH2)2/2LiH composite was prepared with a composition of Mg(NH2)2/2LiH–(0.08 − x)CsH–xKH and the hydrogen storage characteristics was systematically investigated. The results showed that the presence of KH further improved the reaction thermodynamics and kinetics of hydrogen storage in a CsH-containing Mg(NH2)2/2LiH system. A sample with 0.04 mol CsH and 0.04 mol KH had optimal hydrogen storage performance; its dehydrogenation could proceed at 130 °C and hydrogenation at 120 °C with 4.89 wt% of hydrogen storage capacity. At 130 °C a 25-fold increase in the dehydrogenation rate was achieved for the CsH and KH co-doped sample. More importantly the CsH and KH co-doped sample also had good cycling stability because more than 97% of the hydrogen storage capacity (4.34 wt%) remained for theMg(NH2)2/2LiH–0.04CsH–0.04KH sample after 30 cycles. A structural characterization revealed that added CsH and KH participated in the dehydrogenation and hydrogenation reactions by reversibly forming mixed amides of Li–K and Cs–Mg which caused the improved hydrogen storage thermodynamics and kinetics.
East Coast Hydrogen Feasibility Report
Nov 2021
Publication
The highlights of the report include:
- East Coast Hydrogen has the potential to connect up to 7GW of hydrogen production by 2030 alone exceeding the UK Government’s 5GW by 2030 target in a single project. It represents an unmissable opportunity for government and the private sector to work together in delivering on our ambitious decarbonisation targets.
- East Coast Hydrogen can use the natural assets of the North of England including existing and potential hydrogen storage facilities and build on the hydrogen production in two of the UK’s largest industrial clusters in the North East and North West in turn ensuring significant private sector investment in the UK’s industrial heartlands.
- This would be the first step in the conversion of our national gas grid to hydrogen and will act as a blueprint for subsequent conversions across the UK.
- The project will also demonstrate the innovation engineering capabilities and economic opportunity in the North and create tens of thousands of highly skilled Green jobs in the future hydrogen economy."
Novel Fuzzy Control Energy Management Strategy for Fuel Cell Hybrid Electric Vehicles Considering State of Health
Oct 2021
Publication
Due to the low efficiency and high pollution of conventional internal combustion engine vehicles the fuel cell hybrid electric vehicles are expected to play a key role in the future of clean energy transportation attributed to the long driving range short hydrogen refueling time and environmental advantages. The development of energy management strategies has an important impact on the economy and durability but most strategies ignore the aging of fuel cells and the corresponding impact on hydrogen consumption. In this paper a rule-based fuzzy control strategy is proposed based on the constructed data-driven online estimation model of fuel cell health. Then a genetic algorithm is used to optimize this fuzzy controller where the objective function is designed to consider both the economy and durability by combining the hydrogen consumption cost and the degradation cost characterized by the fuel cell health status. Considering that the rule-based strategy is more sensitive to operating conditions this paper uses an artificial neural network for predictive control. The results are compared with those obtained from the genetic algorithm optimized fuzzy controller and are found to be very similar where the prediction accuracy is assessed using MAPE RMSE and 10-fold cross-validation. Experiments show that the developed strategy has a good generalization capability for variable driving cycles.
Reversible Solid-oxide Cell Stack Based Power-to-x-to-power Systems: Comparison of Thermodynamic Performance
Jun 2020
Publication
The increasing penetration of variable renewable energies poses new challenges for grid management. The economic feasibility of grid-balancing plants may be limited by low annual operating hours if they work either only for power generation or only for power storage. This issue might be addressed by a dual-function power plant with power-to-x capability which can produce electricity or store excess renewable electricity into chemicals at different periods. Such a plant can be uniquely enabled by a solid-oxide cell stack which can switch between fuel cell and electrolysis with the same stack. This paper investigates the optimal conceptual design of this type of plant represented by power-to-x-to-power process chains with x being hydrogen syngas methane methanol and ammonia concerning the efficiency (on a lower heating value) and power densities. The results show that an increase in current density leads to an increased oxygen flow rate and a decreased reactant utilization at the stack level for its thermal management and an increased power density and a decreased efficiency at the system level. The power-generation efficiency is ranked as methane (65.9%) methanol (60.2%) ammonia (58.2%) hydrogen (58.3%) syngas (53.3%) at 0.4 A/cm2 due to the benefit of heat-to-chemical-energy conversion by chemical reformulating and the deterioration of electrochemical performance by the dilution of hydrogen. The power-storage efficiency is ranked as syngas (80%) hydrogen (74%) methane (72%) methanol (68%) ammonia (66%) at 0.7 A/cm2 mainly due to the benefit of co-electrolysis and the chemical energy loss occurring in the chemical synthesis reactions. The lost chemical energy improves plant-wise heat integration and compensates for its adverse effect on power-storage efficiency. Combining these efficiency numbers of the two modes results in a rank of round-trip efficiency: methane (47.5%)>syngas (43.3%) ≈ hydrogen (42.6%)>methanol (40.7%)>ammonia (38.6%). The pool of plant designs obtained lays the basis for the optimal deployment of this balancing technology for specific applications.
Analysing Future Demand, Supply, and Transport of Hydrogen
Jun 2021
Publication
Hydrogen is crucial to Europe’s transformation into a climate-neutral continent by mid-century. This study concludes that the European Union (EU) and UK could see a hydrogen demand of 2300 TWh (2150-2750 TWh) by 2050. This corresponds to 20-25% of EU and UK final energy consumption by 2050. Achieving this future role of hydrogen depends on many factors including market frameworks legislation technology readiness and consumer choice.
The document can be download on their website
The document can be download on their website
Hydrogen Production, Distribution, Storage and Power Conversion in a Hydrogen Economy - A Technology Review
Aug 2021
Publication
To meet ambitious targets for greenhouse gas emissions reduction in the 2035-2050 timeframe hydrogen has been identified as a clean “green” fuel of interest. In comparison to fossil fuel use the burning of hydrogen results in zero CO2 emissions and it can be obtained from renewable energy sources. In addition to zero CO2 emissions hydrogen has several other attractive properties such as higher gravimetric energy content and wider flammability limits than most fossil fuels. However there are practical limitations to its widespread use at present which include low volumetric energy density in the gaseous state and high well-to-wheel costs when compared to fossil fuel production and distribution. In this paper a review is undertaken to identify the current state of development of key areas of the hydrogen network such as production distribution storage and power conversion technology. At present high technology costs still are a barrier to widespread hydrogen adoption but it is envisioned that as scale of production increases then costs are likely to fall. Technical barriers to a hydrogen economy adoption are not as significant as one might think as key technologies in the hydrogen network are already mature with working prototypes already developed for technologies such as liquid hydrogen composite cryotanks and proton exchange membrane fuel cells. It is envisioned that with continuous investment to achieve requisite scale that a hydrogen economy could be realised sooner rather than later with novel concepts such as turboelectric distributed propulsion enabled by a shift to hydrogen-powered network.
HyDeploy2 Report: Exemption
Jun 2021
Publication
Exemption is requested by Northern Gas Networks Ltd (NGN) from the obligation set out in Regulation 8(1) of the Gas Safety (Management) Regulations 1996 (GSMR) to convey only natural gas that is compliant with the Interchangeability requirements of Part I of Schedule 3 of the GSMR within a section of the NGN gas distribution network near Winlaton (the “field trial area”). The field trial area is owned and operated by Northern Gas Networks Ltd. The proposed conveyance of non-compliant gas (hereafter called the “Winlaton Field Trial”) will last for one year and is part of the Network Innovation Competition Project “HyDeploy2”.<br/>The project the first two phases of which are funded under the UK Network Innovation Competition scheme aims to demonstrate that natural gas containing levels of hydrogen beyond the upper limit set out in Schedule 3 of in the Gas Safety (Management) Regulations (GSMR) can be distributed and utilised safely and efficiently in the UK gas distribution networks. The first phase of the HyDeploy project is currently underway and includes a 10-month field trial that of hydrogen injection into part of a private gas distribution system owned and operated by Keele University. The second phase of the HyDeploy project (HyDeploy2) continues on from the work of the first phase and is scheduled to conclude with two 12-month field trials in which hydrogen will be injected into public gas networks owned and operated by NGN and Cadent Gas.<br/>Click on the supplements tab to view the other documents from this report
Synthesis and Characterization of Carbon-Based Composites for Hydrogen Storage Application
Dec 2021
Publication
Recent development shows that carbon-based composites are proving to be the most promising materials in hydrogen energy production storage and conversion applications. In this study composites of the copper-based metal-organic framework with different ratios of graphite oxide have been prepared for hydrogen storage application. The developed materials are characterized by X-ray diffraction (XRD) gravimetric thermal analysis (TGA) scanning electron microscopy (SEM) and BET. The newly developed composites have an improved crystalline structure and an increased surface area. The results of the experiment showed that the composite material MOF/GO 20% can store 6.12% of hydrogen at −40 ◦C.
Scenarios to Decarbonize Austria’s Energy Consumption and the Role of Underground Hydrogen Storage
May 2022
Publication
The European Union is aiming at reaching greenhouse gas (GHG) emission neutrality in 2050. Austria’s current greenhouse gas emissions are 80 million t/year. Renewable Energy (REN) contributes 32% to Austria’s total energy consumption. To decarbonize energy consumption a substantial increase in energy generation from renewable energy is required. This increase will add to the seasonality of energy supply and amplifies the seasonality in energy demand. In this paper the seasonality of energy supply and demand in a Net-Zero Scenario are analyzed for Austria and requirements for hydrogen storage derived. We looked into the potential usage of hydrogen in Austria and the economics of hydrogen generation and technology and market developments to assess the Levelized Cost of Hydrogen (LCOH). Then we cover the energy consumption in Austria followed by the REN potential. The results show that incremental potential of up to 140 TWh for hydropower photovoltaic (PV) and wind exists in Austria. Hydropower generation and PV is higher in summer- than in wintertime while wind energy leads to higher energy generation in wintertime. The largest incremental potential is PV with agrivoltaic systems significantly increasing the area amenable for PV compared with PV usage only. Battery Electric Vehicles (BEV) and Fuel Cell Vehicles (FCV) use energy more efficiently than Internal Combustion Engine (ICE) cars; however the use of hydrogen for electricity generation significantly decreases the efficiency due to electricity–hydrogen– electricity conversion. The increase in REN use and the higher demand for energy in Austria in wintertime require seasonal storage of energy. We developed three scenarios Externally Dependent Scenario (EDS) Balanced Energy Scenario (BES) or Self-Sustained Scenario (SSS) for Austria. The EDS scenario assumes significant REN import to Austria whereas the SSS scenario relies on REN generation within Austria. The required hydrogen storage would be 10.82 bn m3 for EDS 13.34 bn m3 for BES and 18.69 bn m3 for SSS. Gas and oil production in Austria and the presence of aquifers indicates that sufficient storage capacity might be available. Significant technology development is required to be able to implement hydrogen as an energy carrier and to balance seasonal energy demand and supply.
Effects of Quantum Confinement of Hydrogen in Nanocavities – Experimental INS Results and New Insights
Jun 2020
Publication
Current developments of non-relativistic quantum mechanics appear to predict and reveal counter-intuitive dynamical effects of hydrogen in nanostructured materials that are of considerable importance for basic research as well as for technological applications. In this review the experimental focus is on H2O and H molecules in carbon nanotubes and other nanocavities that have been experimentally investigated using the well-established technique of incoherent inelastic neutron scattering (INS). For instance the momentum and energy transfers as obtained from the commonly used standard data analysis techniques from a
(I) H2 molecule in a C-nanotube resulting in a roto-translational motion along the nanotube axis seems to (1) either violate the standard conservation laws or (2) to attribute to the H molecule undergoing translation the effective mass a.m.u. (atomic mass units) instead of the expected 2 a.m.u. A similar striking anomalous effect has been found in the neutron-H scattering from the
(II) H2O molecules in nano-channels of some solid materials in which O-H stretching vibrations along the channel axis are created.
The results of this scattering process seem to once again either violate the standard conservation laws or to attribute to the effective mass of the struck H2 molecule as a.m.u. instead of the expected value of 1 a.m.u. We show that these counterintuitive observations from the INS studies have no conventional interpretation within the standard non-relativistic scattering theory. However they can be qualitatively interpreted “from first principles” within the framework of modern theories of
(III) time-symmetric quantum dynamics as provided by the weak values (WV) and two-state- vector formalism (TSVF)
and/or
(IV) quantum correlations especially quantum discord (QD) and quantum thermodynamics (QTD).
The theoretical analysis provides an intuitive understanding of the experimental results gives strong evidence that the nano-structured cavities do represent quantum systems which participate significantly in the dynamics of the neutron-H scattering and surprisingly shows that new physical information can be derived from the experimental data. This latter point may also have far-reaching consequences for technology and material sciences (e.g. fuel cells H storage materials etc.). Moreover novel insights into the short-lived quantum dynamics and/or quantum information theory can be gained.
(I) H2 molecule in a C-nanotube resulting in a roto-translational motion along the nanotube axis seems to (1) either violate the standard conservation laws or (2) to attribute to the H molecule undergoing translation the effective mass a.m.u. (atomic mass units) instead of the expected 2 a.m.u. A similar striking anomalous effect has been found in the neutron-H scattering from the
(II) H2O molecules in nano-channels of some solid materials in which O-H stretching vibrations along the channel axis are created.
The results of this scattering process seem to once again either violate the standard conservation laws or to attribute to the effective mass of the struck H2 molecule as a.m.u. instead of the expected value of 1 a.m.u. We show that these counterintuitive observations from the INS studies have no conventional interpretation within the standard non-relativistic scattering theory. However they can be qualitatively interpreted “from first principles” within the framework of modern theories of
(III) time-symmetric quantum dynamics as provided by the weak values (WV) and two-state- vector formalism (TSVF)
and/or
(IV) quantum correlations especially quantum discord (QD) and quantum thermodynamics (QTD).
The theoretical analysis provides an intuitive understanding of the experimental results gives strong evidence that the nano-structured cavities do represent quantum systems which participate significantly in the dynamics of the neutron-H scattering and surprisingly shows that new physical information can be derived from the experimental data. This latter point may also have far-reaching consequences for technology and material sciences (e.g. fuel cells H storage materials etc.). Moreover novel insights into the short-lived quantum dynamics and/or quantum information theory can be gained.
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