Canada
Experimental Study on Accumulation of Helium Released into a Semi-confined Enclosure without Ventilation
Sep 2019
Publication
This paper examines the helium dispersion behaviour in a 16.6 m3 enclosure with a small opening in the floor and distributed leaks along the edges. Helium a simulant for hydrogen was injected near the center of the floor with an injection rate ranging from 2 to 50 standard liters per minute (Richardson number of 0.3–134) through an upward-facing nozzle. In a short-term transient the helium distribution predicted with the models of Baines & Turner (1969) and Worster & Huppert (1983) matched the measured distributions reasonably well. In a long-term transient the vertical helium profile always reached a steady state which consisted of a homogenous layer at the top overlaying a stratified layer at the bottom. The helium transients in the uniform layer predicted with the models of Lowesmith (2009) and Prasad & Yang (2010) assuming a vent was located in the ceiling were in good agreement with the measured transients.
Experimental Study and Model Predictions on Helium Release in an Enclosure with Single or Multiple Vents
Sep 2021
Publication
This paper presents experiments performed at Canadian Nuclear Laboratories (CNL) to examine the dispersion behaviour of helium in a polycarbonate enclosure that was representative of a residential parking garage. The purpose was to gain a better understanding of the effect of buoyancy- or winddriven natural ventilation on hydrogen dispersion behaviour. Although hydrogen dispersion studies have been reported extensively in the literature gaps still exist in predictive methods for hazard analysis. Helium a simulant for hydrogen was injected near the centre of the floor with a flow rate ranging from 5 to 75 standard litres per minute through an upward-facing nozzle resulting in an injection Richardson number ranging between 10-1 and 102. The location of the nozzle varied from the bottom of the enclosure to near the ceiling to examine the impact of the nozzle elevation on the development of a stratified layer in the upper region of the enclosure. When the injection nozzle was placed at a sufficiently low elevation the vertical helium profile always consisted of a homogenous layer at the top overlaying a stratified layer at the bottom. To simulate outdoor environmental conditions a fan was placed in front of each vent to examine the effect of opposing or assisting wind on the dispersion. The helium transients in the uniform layer predicted with analytical models were in good agreement with the measured transients for the tests with injection at lower elevations or with no wind. Model improvements are required for adequately predicting transients with significantly stratified profiles or with wind.
Hydrogen Strategy for Canada: Seizing the Opportunities for Hydrogen - A Call to Action
Dec 2020
Publication
For more than a century our nation’s brightest minds have been working on the technology to turn the invisible promise of hydrogen into tangible solutions. Canadian ingenuity and innovation has once again brought us to a pivotal moment. As we rebuild our economy from the impacts of COVID-19 and fight the existential threat of climate change the development of low-carbon hydrogen is a strategic priority for Canada. The time to act is now.<br/>The Hydrogen Strategy for Canada lays out an ambitious framework for actions that will cement hydrogen as a tool to achieve our goal of net-zero emissions by 2050 and position Canada as a global industrial leader of clean renewable fuels. This strategy shows us that by 2050 clean hydrogen can help us achieve our net-zero goal—all while creating jobs growing our economy and protecting our environment. This will involve switching from conventional gasoline diesel and natural gas to zero-emissions fuel sources taking advantage of new regulatory environments and embracing new technologies to give Canadians more choice of zero emission alternatives.<br/>As one of the top 10 hydrogen producers in the world today we are rich in the feedstocks that produce hydrogen. We are blessed with a strong energy sector and the geographic assets that will propel Canada to be a major exporter of hydrogen and hydrogen technologies. Hydrogen might be nature’s smallest molecule but its potential is enormous. It provides new markets for our conventional energy resources and holds the potential to decarbonize many sectors of our economy including resource extraction freight transportation power generation manufacturing and the production of steel and cement. This Strategy is a call to action. It will spur investments and strategic partnerships across the country and beyond our borders. It will position Canada to seize economic and environmental opportunities that exist coast to coast. Expanding our exports. Creating as many as 350000 good green jobs over the next three decades. All while dramatically reducing our greenhouse gas emissions. And putting a net-zero future within our reach.<br/>The importance of Canada’s resource industries and our clean technology sectors has been magnified during the pandemic. We must harness our combined will expertise and financial resources to fully seize the opportunities that hydrogen presents. This strategy is the product of three years of study and analysis including extensive engagement sessions where we heard from more than 1500 of our country’s leading experts and stakeholders. But its release is not the end of a process. This is only the beginning. Together we will use this Strategy to guide our actions and investments. By working with provinces and territories Indigenous partners and the private-sector and by leveraging our many advantages we will create the prosperity we all want protect the planet we all cherish and we will ensure we leave no one behind.
Bayesian Inference and Uncertainty Quantification for Hydrogen-Enriched and Lean-Premixed Combustion Systems
May 2021
Publication
Development of probabilistic modelling tools to perform Bayesian inference and uncertainty quantification (UQ) is a challenging task for practical hydrogen-enriched and low-emission combustion systems due to the need to take into account simultaneously simulated fluid dynamics and detailed combustion chemistry. A large number of evaluations is required to calibrate models and estimate parameters using experimental data within the framework of Bayesian inference. This task is computationally prohibitive in high-fidelity and deterministic approaches such as large eddy simulation (LES) to design and optimize combustion systems. Therefore there is a need to develop methods that: (a) are suitable for Bayesian inference studies and (b) characterize a range of solutions based on the uncertainty of modelling parameters and input conditions. This paper aims to develop a computationally-efficient toolchain to address these issues for probabilistic modelling of NOx emission in hydrogen-enriched and lean-premixed combustion systems. A novel method is implemented into the toolchain using a chemical reactor network (CRN) model non-intrusive polynomial chaos expansion based on the point collocation method (NIPCE-PCM) and the Markov Chain Monte Carlo (MCMC) method. First a CRN model is generated for a combustion system burning hydrogen-enriched methane/air mixtures at high-pressure lean-premixed conditions to compute NOx emission. A set of metamodels is then developed using NIPCE-PCM as a computationally efficient alternative to the physics-based CRN model. These surrogate models and experimental data are then implemented in the MCMC method to perform a two-step Bayesian calibration to maximize the agreement between model predictions and measurements. The average standard deviations for the prediction of exit temperature and NOx emission are reduced by almost 90% using this method. The calibrated model then used with confidence for global sensitivity and reliability analysis studies which show that the volume of the main-flame zone is the most important parameter for NOx emission. The results show satisfactory performance for the developed toolchain to perform Bayesian inference and UQ studies enabling a robust and consistent process for designing and optimising low-emission combustion systems.
The ‘Green’ Ni-UGSO Catalyst for Hydrogen Production under Various Reforming Regimes
Jun 2021
Publication
A new spinelized Ni catalyst (Ni-UGSO) using Ni(NO3)2·6H2O as the Ni precursor was prepared according to a less material intensive protocol. The support of this catalyst is a negative-value mining residue UpGraded Slag Oxide (UGSO) produced from a TiO2 slag production unit. Applied to dry reforming of methane (DRM) at atmospheric pressure T = 810 °C space velocity of 3400 mL/(h·g) and molar CO2/CH4 = 1.2 Ni-UGSO gives a stable over 168 h time-on-stream methane conversion of 92%. In this DRM reaction optimization study: (1) the best performance is obtained with the 10–13 wt% Ni load; (2) the Ni-UGSO catalysts obtained from two different batches of UGSO demonstrated equivalent performances despite their slight differences in composition; (3) the sulfur-poisoning resistance study shows that at up to 5.5 ppm no Ni-UGSO deactivation is observed. In steam reforming of methane (SRM) Ni-UGSO was tested at 900 °C and a molar ratio of H2O/CH4 = 1.7. In this experimental range CH4 conversion rapidly reached 98% and remained stable over 168 h time-on-stream (TOS). The same stability is observed for H2 and CO yields at around 92% and 91% respectively while H2/CO was close to 3. In mixed (dry and steam) methane reforming using a ratio of H2O/CH4 = 0.15 and CO2/CH4 = 0.97 for 74 h and three reaction temperature levels (828 °C 847 °C and 896 °C) CH4 conversion remains stable; 80% at 828 °C (26 h) 85% at 847 °C (24 h) and 95% at 896 °C (24 h). All gaseous streams have been analyzed by gas chromatography. Both fresh and used catalysts are analyzed by scanning electron microscopy-electron dispersive X-ray spectroscopy (SEM-EDXS) X-ray diffraction (XRD) and thermogravimetric analysis (TGA) coupled with mass spectroscopy (MS) and BET Specific surface. In the reducing environment of reforming such catalytic activity is mainly attributed to (a) alloys such as FeNi FeNi3 and Fe3Ni2 (reduction of NiFe2O4 FeNiAlO4) and (b) to the solid solution NiO-MgO. The latter is characterized by a molecular distribution of the catalytically active Ni phase while offering an environment that prevents C deposition due to its alkalinity.
Recent Advances in High-Temperature Steam Electrolysis with Solid Oxide Electrolysers for Green Hydrogen Production
Apr 2023
Publication
Hydrogen is known to be the carbon-neutral alternative energy carrier with the highest energy density. Currently more than 95% of hydrogen production technologies rely on fossil fuels resulting in greenhouse gas emissions. Water electrolysis is one of the most widely used technologies for hydrogen generation. Nuclear power a renewable energy source can provide the heat needed for the process of steam electrolysis for clean hydrogen production. This review paper analyses the recent progress in hydrogen generation via high-temperature steam electrolysis through solid oxide electrolysis cells using nuclear thermal energy. Protons and oxygen-ions conducting solid oxide electrolysis processes are discussed in this paper. The scope of this review report covers a broad range including the recent advances in material development for each component (i.e. hydrogen electrode oxygen electrode electrolyte interconnect and sealant) degradation mechanisms and countermeasures to mitigate them.
Modelling the Impacts of Hydrogen–Methane Blend Fuels on a Stationary Power Generation Engine
Mar 2023
Publication
To reduce greenhouse gas emissions from natural gas use utilities are investigating the potential of adding hydrogen to their distribution grids. This will reduce the carbon dioxide emissions from grid-connected engines used for stationary power generation and it may also impact their power output and efficiency. Promisingly hydrogen and natural gas mixtures have shown encouraging results regarding engine power output pollutant emissions and thermal efficiency in well-controlled on-road vehicle applications. This work investigates the effects of adding hydrogen to the natural gas fuel for a lean-burn spark-ignited four-stroke 8.9 liter eight-cylinder naturally aspirated engine used in a commercial stationary power generation application via an engine model developed in the GT-SUITETM modelling environment. The model was validated for fuel consumption air flow and exhaust temperature at two operating modes. The focus of the work was to assess the sensitivity of the engine’s power output brake thermal efficiency and pollutant emissions to blends of methane with 0–30% (by volume) hydrogen. Without adjusting for the change in fuel energy the engine power output dropped by approximately 23% when methane was mixed with 30% by volume hydrogen. It was found that increasing the fueling rate to maintain a constant equivalence ratio prevented this drop in power and reduced carbon dioxide emissions by almost 4.5%. In addition optimizing the spark timing could partially offset the increases in in-cylinder burned and unburned gas temperatures and in-cylinder pressures that resulted from the faster combustion rates when hydrogen was added to the natural gas. Understanding the effect of fuel change in existing systems can provide insight on utilizing hydrogen and natural gas mixtures as the primary fuel without the need for major changes in the engine.
Improvement of MC Method in SAE J2601 Hydrogen Refuelling Protocol Using Dual-zone Dual-Temperature Model
Sep 2023
Publication
The MC method refuelling protocol in SAE J2601 has been published by the Society of Automotive Engineers (SAE) in order to safely and quickly refuel hydrogen vehicles. For the calculation method of the pressure target to control the refuelling stop we introduced a dual-zone dual-temperature model that distinguishes the hydrogen temperature in the tank from the wall temperature to replace the dual-zone single-temperature model of the original MC method. The total amount of heat transferred by convection between hydrogen and the inner tank wall during the filling process was expressed as an equation of final hydrogen temperature final wall temperature final refuelling time tank inner surface area and the correction factor. The correction factor equations were determined by fitting simulation data from the 0D1D model where hydrogen inside the tank is lumped parameter model (0D) and the tank wall is a one-dimensional model (1D). For the correction factor of the linear equation its first-order coefficient and constant term have a linear relationship with the initial pressure of the storage tank and their R2 values obtained from the fitting are greater than 0.99. Finally we derived a new equation to calculate the final hydrogen temperature which can be combined with the 100% SOC inside the vehicle tank to determine the pressure target. The simulation results show that the final SOC obtained are all greater than 96% using the modified pressure target and the correction factor of the linear equation.
A Techno-economic Study of the Strategy for Hydrogen Transport by Pipelines in Canada
Jan 2023
Publication
Hydrogen as a clean zero-emission energy fuel will play a critical role in energy transition and achievement of the net-zero target in 2050. Hydrogen delivery is integral to the entire value chain of a full-scale hydrogen economy. This work conducted a systematic review and analysis of various hydrogen transportation methods including truck tankers for liquid hydrogen tube trailers for gaseous hydrogen and pipelines by identifying and ranking the main properties and affecting factors associated with each method. It is found that pipelines especially the existing natural gas pipelines provide a more efficient and cheaper means to transport hydrogen over long distances. Analysis was further conducted on Canadian natural gas pipeline network which has been operating for safe effective and efficient energy transport over six decades. The established infrastructure along with the developed operating and management experiences and skillful manpower makes the existing pipelines the best option for transport of hydrogen in either blended or pure form in the country. The technical challenges in repurposing the existing natural gas pipelines for hydrogen service were discussed and further work was analyzed.
A Review of the Status of Fossil and Renewable Energies in Southeast Asia and Its Implications on the Decarbonization of ASEAN
Mar 2022
Publication
The ten nations of Southeast Asia collectively known as ASEAN emitted 1.65 Gtpa CO2 in 2020 and are among the most vulnerable nations to climate change which is partially caused by anthropogenic CO2 emission. This paper analyzes the history of ASEAN energy consumption and CO2 emission from both fossil and renewable energies in the last two decades. The results show that ASEAN’s renewable energies resources range from low to moderate are unevenly distributed geographically and contributed to only 20% of total primary energy consumption (TPEC) in 2015. The dominant forms of renewable energies are hydropower solar photovoltaic and bioenergy. However both hydropower and bioenergy have substantial sustainability issues. Fossil energies depend heavily on coal and oil and contribute to 80% of TPEC. More importantly renewable energies’ contribution to TPEC has been decreasing in the last two decades despite the increasing installation capacity. This suggests that the current rate of the addition of renewable energy capacity is inadequate to allow ASEAN to reach net-zero by 2050. Therefore fossil energies will continue to be an important part of ASEAN’s energy mix. More tools such as carbon capture and storage (CCS) and hydrogen will be needed for decarbonization. CCS will be needed to decarbonize ASEAN’s fossil power and industrial plants while blue hydrogen will be needed to decarbonize hard-to-decarbonize industrial plants. Based on recent research into regional CO2 source-sink mapping this paper proposes six large-scale CCS projects in four countries which can mitigate up to 300 Mtpa CO2 . Furthermore this paper identifies common pathways for ASEAN decarbonization and their policy implications.
A Novel Approach for Quantifying Hydrogen Embrittlement Using Side-grooved CT Samples
Feb 2022
Publication
Aerospace parts made of high strength steels such as landing gears and helicopter transmissions are often electroplated to satisfy various engineering specifications. However plated parts are occasionnaly rejected because of hydrogen embrittlement and the industry has few means of evaluating quantitatively the actual damage caused by hydrogen. In the present article we developed a novel method to measure the stress intensity threshold for hydrogen embrittlement (Kth) in industrial plating conditions. The method consists in plating side-grooved CT samples in industrial plating baths and measuring Kth with an incremental step loading methodology. We validated the method with a benchmark case known to produce embrittlement (omitted post-plating bake) and we used the method on a test case for which the level of embrittlement was unknown (delayed bake). For the benchmark case we measured a Kth of 49.0 MPa m0.5 for non-baked samples. This value is significantly lower than the fracture toughness of the unplated material which is 63.8 MPa m0.5 . We conclude that this novel combination of geometry and test method is efficient in quantifying hydrogen embrittlement of samples plated in industrial conditions. For the test case the Kth are respectively 57.9 MPa m0.5 and 58.8 MPa m0.5 for samples baked 100 h and 4 h after plating. We conclude that delaying the post-plating bake does not cause hydrogen embrittlement in the studied conditions. Using a finite element hydrogen diffusion analysis we argue that the side grooves on CT samples increase the sensitivity to hydrogen embrittlement in comparison to smooth samples. In smooth samples a zone of plane stress at the surface of the specimen shields hydrogen from penetrating to the center of the specimen a phenomenon which is alleviated with machining side grooves.
Accumulation of Inert Impurities in a Polymer Electrolyte Fuel Cell System with Anode Recirculation and Periodic Purge: A Simple Analytical Model
Mar 2022
Publication
Anode recirculation with periodic purge is commonly used in polymer electrolyte fuel cell systems to control the accumulation of nitrogen water and other impurities that are present in the fuel or diffuse through the membrane from the cathode compartment. In this work we develop a simple generalized analytical model that simulates the time dependence of the accumulation of inert impurities in the anode compartment of such a system. It is shown that when there is transport out of the anode chamber the inert species is expected to accumulate exponentially until equilibrium is reached when the rate of inert entering the anode in the fuel supply and/or via crossover from the cathode is balanced by the rate of leakage and/or crossover to the cathode. The model is validated using recently published experimental data for the accumulation of N2 CH4 and CO2 in a recirculated system. The results show that nitrogen accumulation needs to be taken into account to properly adjust system parameters such as purge rate purge volume and recirculation rate. The use of this generalized analytical model is intended to aid the selection of these system parameters to optimize performance in the presence of inerts.
On the Bulk Transport of Green Hydrogen at Sea: Comparison Between Submarine Pipeline and Compressed and Liquefied Transport by Ship
Jan 2023
Publication
This paper compares six (6) alternatives for green hydrogen transport at sea. Two (2) alternatives of liquid hydrogen (LH2) by ship two (2) alternatives of compressed hydrogen (cH2) by ship and two (2) alternatives of hydrogen by pipeline. The ship alternatives study having hydrogen storage media at both end terminals to reduce the ships’ time at port or prescinding of them and reduce the immobilized capital. In the case of the pipeline new models are proposed by considering pressure costs. One scenario considers that there are compression stations every 500 km and the other one considers that there are none along the way. These alternatives are assessed under nine different scenarios that combine three distances: 100 km 2500 km and 5000 km; and three export rates of hydrogen 100 kt/y 1 Mt/y and 10 Mt/y. The results show including uncertainty bands that for the 100 km of distance the best alternative is the pipeline. For 2500 km and 100 kt/y the top alternative is cH2 shipping without storage facilities at the port terminals. For 2500 km and 1 Mt/y and for 5000 km and 100 kt/y the best alternatives are cH2 or LH2 shipping. For the remaining scenarios the best alternative is LH2 shipping.
Techno-economic Assessment of Low-carbon Hydrogen Export from Western Canada to Eastern Canada, the USA, the Asia-Pacific, and Europe
Dec 2021
Publication
The use of low-carbon hydrogen is being considered to help decarbonize several jurisdictions around the world. There may be opportunities for energy-exporting countries to supply energy-importing countries with a secure source of low-carbon hydrogen. The study objective is to assess the delivered cost of gaseous hydrogen export from Canada (a fossil-resource rich country) to the Asia-Pacific Europe and inland destinations in North America. There is a data gap on the feasibility of inter-continental export of hydrogen from an energy-producing jurisdiction to energy-consuming jurisdictions. This study is aimed at addressing this gap and includes an assessment of opportunities across the Pacific Ocean and the Atlantic Ocean based on fundamental engineering-based models. Techno-economics were used to determine the delivered cost of hydrogen to these destinations. The modelling considers energy material and capacity-sizing requirements for a five-stage supply chain comprising hydrogen production with carbon capture and storage hydrogen pipeline transportation liquefaction shipping and regasification at the destinations. The results show that the delivered cost of hydrogen to inland destinations in North America is between CAD$4.81/kg and CAD$6.03/kg to the Asia-Pacific from CAD$6.65/kg to CAD$6.99/kg and at least CAD$8.14/kg for exports to Europe. Delivering hydrogen by blending in existing long-distance natural gas pipelines reduced the delivered cost to inland destinations by 17%. Exporting ammonia to the Asia-Pacific provides cost savings of 28% compared to shipping liquified hydrogen. The developed information may be helpful to policymakers in government and the industry in making informed decisions about international trade of low-carbon hydrogen in both energy-exporting and energy-importing jurisdictions globally.
Thermodynamics and Kinetics of Hydriding and Dehydriding Reactions in Mg-based Hydrogen Storage Materials
Oct 2021
Publication
Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity environmental benignity and high Clarke number characteristics. However the limited thermodynamics and kinetic properties pose major challenges for their engineering applications. Herein we review the recent progress in improving their thermodynamics and kinetics with an emphasis on the models and the influence of various parameters in the calculated models. Subsequently the impact of alloying composite and nano-crystallization on both thermodynamics and dynamics are discussed in detail. In particular the correlation between various modification strategies and the hydrogen capacity dehydrogenation enthalpy and temperature hydriding/dehydriding rates are summarized. In addition the mechanism of hydrogen storage processes of Mg-based materials is discussed from the aspect of classical kinetic theories and microscope hydrogen transferring behavior. This review concludes with an outlook on the remaining challenge issues and prospects.
Cost and Capacity Requirements of Electrification or Renewable Gas Transition Options that Decarbonize Building Heating in Metro Vancouver, British Columbia
Jun 2022
Publication
Northern countries face a unique challenge in decarbonizing heating demands. This study compares two pathways to reduce carbon emissions from building heating by (1) replacing natural gas heaters with electric heat pumps or (2) replacing natural gas with renewable gas. Optimal annual system cost and capacity requirements for Metro Vancouver Canada are assessed for each pathway under nine scenarios. Results show that either pathway can be lower cost but the range of costs is more narrow for the renewable gas pathway. System cost is sensitive to heat demand with colder temperatures favouring the renewable gas pathway and milder temperatures favouring the electrification pathway. These results highlight the need for a better understanding of heating profiles and associated energy system requirements.
Large-scale Long-distance Land-based Hydrogen Transportation Systems: A Comparative Techno-economic and Greenhouse Gas Emission Assessment
Aug 2022
Publication
Interest in hydrogen as an energy carrier is growing as countries look to reduce greenhouse gas (GHG) emissions in hard-to-abate sectors. Previous works have focused on hydrogen production well-to-wheel analysis of fuel cell vehicles and vehicle refuelling costs and emissions. These studies use high-level estimates for the hydrogen transportation systems that lack sufficient granularity for techno-economic and GHG emissions analysis. In this work we assess and compare the unit costs and emission footprints (direct and indirect) of 32 systems for hydrogen transportation. Process-based models were used to examine the transportation of pure hydrogen (hydrogen pipeline and truck transport of gaseous and liquified hydrogen) hydrogen-natural gas blends (pipeline) ammonia (pipeline) and liquid organic hydrogen carriers (pipeline and rail). We used sensitivity and uncertainty analyses to determine the parameters impacting the cost and emission estimates. At 1000 km the pure hydrogen pipelines have a levelized cost of $0.66/kg H2 and a GHG footprint of 595 gCO2eq/kg H2. At 1000 km ammonia liquid organic hydrogen carrier and truck transport scenarios are more than twice as expensive as pure hydrogen pipeline and hythane and more than 1.5 times as expensive at 3000 km. The GHG emission footprints of pure hydrogen pipeline transport and ammonia transport are comparable whereas all other transport systems are more than twice as high. These results may be informative for government agencies developing policies around clean hydrogen internationally.
Potential for Natural Hydrogen in Quebec (Canada): A First Review
Mar 2024
Publication
The energy transition calls for natural hydrogen exploration with most occurrences discovered either inadvertently or more recently at the location of potentially diffusive circles observed from a change of vegetation cover at the surface. However some notable hydrogen occurrences are not directly associated with the presence of diffusive circles like the Bourakebougou field in Mali. Thus the objective of this work was to highlight geological areas that have some potential to find natural hydrogen in Quebec a Canadian province where no diffusive circles have yet been documented but which is rich in potential source rocks and where no exploration for natural hydrogen has been undertaken so far. A review of the different geological regions of Quebec was undertaken to highlight the relevant characteristics and geographical distribution of geological assemblages that may produce or have produced natural hydrogen in particular iron-rich rocks but also uranium-rich rocks supramature shales and zones where significant structural discontinuities are documented or suspected which may act as conduits for the migration of fluids of mantle origin. In addition to regional and local geological data an inventory of available geochemical data is also carried out to identify potential tracers or proxies to facilitate subsequent exploration efforts. A rating was then proposed based on the quality of the potential source rocks which also considers the presence of reservoir rocks and the proximity to end-users. This analysis allowed rating areas of interest for which fieldwork can be considered thus minimizing the exploratory risks and investments required to develop this resource. The size of the study area (over 1.5 million km2 ) the diversity of its geological environments (from metamorphic cratons to sedimentary basins) and their wide age range (from Archean to Paleozoic) make Quebec a promising territory for natural hydrogen exploration and to test the systematic rating method proposed here.
Two-stage Model Predictive Control for a Hydrogen-based Storage System Paired to a Wind Farm Towards Green Hydrogen Production for Fuel Cell Electric Vehicles
Jul 2022
Publication
This study proposes a multi-level model predictive control (MPC) for a grid-connected wind farm paired to a hydrogen-based storage system (HESS) to produce hydrogen as a fuel for commercial road vehicles while meeting electric and contractual loads at the same time. In particular the integrated system (wind farm + HESS) should comply with the “fuel production” use case as per the IEA-HIA report where the hydrogen production for fuel cell electric vehicles (FCEVs) has the highest unconditional priority among all the objectives. Based on models adopting mixed-integer constraints and dynamics the problem of external hydrogen consumer requests optimal load demand tracking and electricity market participation is solved at different timescales to achieve a long-term plan based on forecasts that then are adjusted at real-time. The developed controller will be deployed onto the management platform of the HESS which is paired to a wind farm established in North Norway within the EU funded project HAEOLUS. Numerical analysis shows that the proposed controller efficiently manages the integrated system and commits the equipment so as to comply with the requirements of the addressed scenario. The operating costs of the devices are reduced by 5% which corresponds to roughly 300 commutations saved per year for devices.
A Comparative Study of CFD-Modelling for Lean Premixed Hydrogen Deflagrations in Large-scale Vented Vessels
Sep 2021
Publication
Hydrogen combustion inside a post-accident nuclear reactor containment may pose a challenge to the containment integrity which could alter the fission-product release source term to the public. Combustion-generated overpressures may be relieved by venting to adjacent compartments through relief panels or existing openings. Thus an improved understanding of the propagation of lean hydrogen deflagrations in inter-connected compartments is essential for the development of appropriate management strategies. GOTHIC is a general purpose lumped parameter thermal-hydraulic code for solving multi-phase compressible flows which is accepted as an industry-standard code for containment safety analyses. Following the Fukushima accident the application of three-dimensional computational fluid dynamics methods to high-fidelity detailed analysis of hydrogen combustion processes has become more widespread. In this study a recently developed large-eddy-simulation (LES) capability is applied to the prediction of lean premixed hydrogen deflagrations in large-scale vented vessels of various configurations. The LES predictions are compared with GOTHIC predictions and experimental data obtained from the large-scale vented combustion test facility at the Canadian Nuclear Laboratories. The LES methodology makes use of a flamelet- or a progress-variable-based combustion model. An empirical burning velocity model is combined with an advanced finite-volume framework and a mesh-independent subfilter-scale model. Descriptions of the LES and GOTHIC modelling approaches used to simulate the hydrogen reactive flows in the vented vessels along with the experimental data sets are given. The potential and limitations of the lumped parameter and LES approaches for accurately describing lean premixed hydrogen deflagrations in vented vessels are discussed.
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