Netherlands
Evaluation of Selectivity and Resistance to Poisons of Commercial Hydrogen Sensors
Sep 2013
Publication
The development of reliable hydrogen sensors is crucial for the safe use of hydrogen. One of the main concerns of end-users is sensor reliability in the presence of species other than the target gas which can lead to false alarms or undetected harmful situations. In order to assess the selectivity of commercial of the shelf (COTS) hydrogen sensors a number of sensors of different technology types were exposed to various interferent gas spec Read More
Simulation of the Inelastic Deformation of Porous Reservoirs Under Cyclic Loading Relevant for Underground Hydrogen Storage
Dec 2022
Publication
Subsurface geological formations can be utilized to safely store large-scale (TWh) renewable energy in the form of green gases such as hydrogen. Successful implementation of this technology involves estimating feasible storage sites including rigorous mechanical safety analyses. Geological formations are often highly heterogeneous and entail complex nonlinear inelastic rock deformation physics when utilized for cyclic energy storage. In this work we pres Read More
The Potential of Green Ammonia Production to Reduce Renewable Power Curtailment and Encourage the Energy Transition in China
Apr 2022
Publication
The pursuing of inter-regional power transmission to address renewable power curtailment in China has resulted in disappointing gains. This paper evaluates the case of local green ammonia production to address this issue. An improved optimization-based simulation model is applied to simulate lifetime green manufacturing and the impacts of main institutional incentives and oxygen synergy on investment are analysed. Levelized cost of ammonia is esti Read More
Cost-optimal Reliable Power Generation in a Deep Decarbonisation Future
Jul 2019
Publication
Considering the targets of the Paris agreement rapid decarbonisation of the power system is needed. In order to study cost-optimal and reliable zero and negative carbon power systems a power system model of Western Europe for 2050 is developed. Realistic future technology costs demand levels and generator flexibility constraints are considered. The optimised portfolios are tested for both favourable and unfavourable future weather condition Read More
Potential and Challenges of Low-carbon Energy Options: Comparative Assessment of Alternative Fuels for the Transport Sector
Dec 2018
Publication
The deployment of low-emission alternative fuels is crucial to decarbonise the transport sector. A number of alternatives like hydrogen or dimethyl ether/methanol synthesised using CO2 as feedstock for fuel production (hereafter refer to “CO2-based fuels”) have been proposed to combat climate change. However the decarbonisation potential of CO2-based fuels is under debate because CO2 is re-emitted to the atmosphere when the fuel is Read More
Analysis of Photon-driven Solar-to-hydrogen Production Methods in the Netherlands
Oct 2021
Publication
Hydrogen is deemed necessary for the realization of a sustainable society especially when renewable energy is used to generate hydrogen. As most of the photon-driven hydrogen production methods are not commercially available yet this study has investigated the techno economic and overall performance of four different solar-to hydrogen methods and photovoltaics-based electrolysis methods in the Netherlands. It was found that the photovoltaics-bas Read More
Power-to-gas in Electricity Markets Dominated by Renewables
Oct 2018
Publication
This paper analyses the feasibility of power-to-gas in electricity markets dominated by renewables. The business case of a power-to-gas plant that is producing hydrogen is evaluated by determining the willingness to pay for electricity and by comparing this to the level and volatility of electricity prices in a number of European day-ahead markets. The short-term willingness to pay for electricity depends on the marginal costs and revenues of the plan Read More
A Comparison of Steam Reforming Concepts in Solid Oxide Fuel Cell Systems
Mar 2020
Publication
Various concepts have been proposed to use hydrocarbon fuels in solid oxide fuel cell (SOFC) systems. A combination of either allothermal or adiabatic pre-reforming and water recirculation (WR) or anode off-gas recirculation (AOGR) is commonly used to convert the fuel into a hydrogen rich mixture before it is electrochemically oxidised in the SOFC. However it is unclear how these reforming concepts affect the electrochemistry and temperature gradient Read More
Sector Coupling via Hydrogen to Lower the Cost of Energy System Decarbonization
Aug 2021
Publication
There is growing interest in using hydrogen (H2) as a long-duration energy storage resource in a future electric grid dominated by variable renewable energy (VRE) generation. Modeling H2 use exclusively for grid-scale energy storage often referred to as ‘‘power-to-gas-to-power (P2G2P)’’ overlooks the cost-sharing and CO2 emission benefits from using the deployed H2 assets to decarbonize other end-use sectors where direct electrification is challenging. Her Read More
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 Read More
Flexible Power & Biomass-to-Methanol Plants: Design Optimization and Economic Viability of the Electrolysis Integration
Nov 2021
Publication
This paper assesses the optimal design criteria of a flexible power and biomass to methanol (PBtM) plant conceived to operate both without green hydrogen addition (baseline mode) and with hydrogen addition (enhanced mode) following an intermittent use of the electrolysis system which is turned on when the electricity price allows an economically viable hydrogen production. The assessed plant includes a gasification section syngas cleaning and compr Read More
Transient Reversible Solid Oxide Cell Reactor Operation – Experimentally Validated Modeling and Analysis
Oct 2018
Publication
A reversible solid oxide cell (rSOC) reactor can operate efficiently in both electrolysis mode and in fuel cell mode. The bidirectional operability enables rSOC reactors to play a central role as an efficient energy conversion system for energy storage and sector coupling for a renewable energy driven society. A combined system for electrolysis and fuel cell operation can result in complex system configurations that should be able to switch between the tw Read More
Wind Power to Methanol: Renewable Methanol Production Using Electricity, Electrolysis of Water and CO2 Air Capture
Feb 2020
Publication
A 100 MW stand-alone wind power to methanol process has been evaluated to determine the capital requirement and power to methanol efficiency. Power available for electrolysis determines the amount of hydrogen produced. The stoichiometric amount of CO2– required for the methanol synthesis – is produced using direct air capture. Integration of utilities for CO2 air capture hydrogen production from co-harvested water and methanol synthesi Read More
The Membrane-assisted Chemical Looping Reforming Concept for Efficient H2 Production with Inherent CO2 Capture: Experimental Demonstration and Model Validation
Feb 2018
Publication
In this work a novel reactor concept referred to as Membrane-Assisted Chemical Looping Reforming (MA-CLR) has been demonstrated at lab scale under different operating conditions for a total working time of about 100 h. This reactor combines the advantages of Chemical Looping such as CO2 capture and good thermal integration with membrane technology for a better process integration and direct product separation in a single unit which in its tur Read More
Potential Role of Natural Gas Infrastructure in China to Supply Low-carbon Gases During 2020–2050
Oct 2021
Publication
As natural gas (NG) demand increases in China the question arises how the NG infrastructure fit into a low greenhouse gas (GHG) emissions future towards 2050. Herein the potential role of the NG infrastructure in supplying low-carbon gases during 2020–2050 for China at a provincial resolution was analyzed for different scenarios. In total four low-carbon gases were considered in this study: biomethane bio-synthetic methane hydrogen and low-carbon synt Read More
Perspective on the Hydrogen Economy as a Pathway to Reach Net-zero CO2 Emissions in Europe
Jan 2022
Publication
The envisioned role of hydrogen in the energy transition – or the concept of a hydrogen economy – has varied through the years. In the past hydrogen was mainly considered a clean fuel for cars and/or electricity production; but the current renewed interest stems from the versatility of hydrogen in aiding the transition to CO2 neutrality where the capability to tackle emissions from distributed applications and complex industrial processes is of paramoun Read More
Renaissance of Ammonia Synthesis for Sustainable Production of Energy and Fertilizers
Feb 2021
Publication
Green ammonia synthesis via the Haber–Bosch (HB) process has become a major field of research in the recent years for production of fertilizers and seasonal energy storage due to drastic drop in cost of renewable hydrogen. While the field of catalysis and engineering has worked on this subject for many years the current process of ammonia synthesis remains essentially unaltered. As a result current industrial developments on green ammonia are Read More
Greenhouse Gas Implications of Extending the Service Life of PEM Fuel Cells for Automotive Applications: A Life Cycle Assessment
Feb 2022
Publication
A larger adoption of hydrogen fuel-cell electric vehicles (FCEVs) is typically included in the strategies to decarbonize the transportation sector. This inclusion is supported by life-cycle assessments (LCAs) which show the potential greenhouse gas (GHG) emission benefit of replacing internal combustion engine vehicles with their fuel cell counterpart. However the literature review performed in this study shows that the effects of durability and performance losses Read More
Techno-economic Analysis of Developing an Underground Hydrogen Storage Facility in Depleted Gas Field: A Dutch Case Study
Apr 2023
Publication
Underground hydrogen storage will be an essential part of the future hydrogen infrastructure to provide flexibility and security of supply. Storage in porous reservoirs should complement storage in salt caverns to be able to meet the projected high levels of required storage capacities. To assess its techno-economic feasibility a case study of hydrogen storage in a depleted gas field in the Netherlands is developed. Subsurface modelling is performed Read More
Benefits of an Integrated Power and Hydrogen Offshore Grid in a Net-zero North Sea Energy System
Jun 2022
Publication
The North Sea Offshore Grid concept has been envisioned as a promising alternative to: 1) ease the integration of offshore wind and onshore energy systems and 2) increase the cross-border capacity between the North Sea region countries at low cost. In this paper we explore the techno-economic benefits of the North Sea Offshore Grid using two case studies: a power-based offshore grid where only investments in power assets are allowed (i.e. offshore win Read More
Dynamic Operation of Water Electrolyzers: A Review for Applications in Photovoltaic Systems Integration
May 2023
Publication
This review provides a comprehensive overview of the dynamics of low-temperature water electrolyzers and their influence on coupling the three major technologies alkaline Proton Exchange Membrane (PEM) and Anion Exchange Membrane (AEM) with photovoltaic (PV) systems. Hydrogen technology is experiencing considerable interest as a way to accelerate the energy transition. With no associated CO2 emissions and fast response water electr Read More
Selection Criteria and Ranking for Sustainable Hydrogen Production Options
Aug 2022
Publication
This paper aims to holistically study hydrogen production options essential for a sustainable and carbon-free future. This study also outlines the benefits and challenges of hydrogen production methods to provide sustainable alternatives to fossil fuels by meeting the global energy demand and net-zero targets. In this study sixteen hydrogen production methods are selected for sustainability investigation based on seven different criteria. The criteria selected Read More
Exploring Supply Chain Design and Expansion Planning of China's Green Ammonia Production with an Optimization-based Simulation Approach
Aug 2021
Publication
Green ammonia production as an important application for propelling the upcoming hydrogen economy has not been paid much attention by China the world's largest ammonia producer. As a result related studies are limited. This paper explores potential supply chain design and planning strategies of green ammonia production in the next decade of China with a case study in Inner Mongolia. A hybrid optimization-based simulation approach is applied c Read More
A Green Hydrogen Energy System: Optimal Control Strategies for Integrated Hydrogen Storage and Power Generation with Wind Energy
Jul 2022
Publication
The intermittent nature of renewable energy resources such as wind and solar causes the energy supply to be less predictable leading to possible mismatches in the power network. To this end hydrogen production and storage can provide a solution by increasing flexibility within the system. Stored hydrogen as compressed gas can either be converted back to electricity or it can be used as feed-stock for industry heating for built environment Read More
Permeation Tests in Type-approval Regulations for Hydrogen Fuelled Vehicles: Analysis and Testing Experiences at the JRC-GASTEF Facility
Jan 2023
Publication
This article presents an analysis of the permeation tests established in the current regulations for the type-approval of on board tanks in hydrogen vehicles. The analysis is done from the point of view of a test maker regarding the preparation for the execution of a permeation test. The article contains a description of the required instrumentation and set-up to carry out a permeation test according to the applicable standards and regulations. Tank Read More
Production Costs for Synthetic Methane in 2030 and 2050 of an Optimized Power-to-Gas Plant with Intermediate Hydrogen Storage
Aug 2019
Publication
The publication gives an overview of the production costs of synthetic methane in a Power-to-Gas process. The production costs depend in particularly on the electricity price and the full load hours of the plant sub-systems electrolysis and methanation. The full-load hours of electrolysis are given by the electricity supply concept. In order to increase the full-load hours of methanation the size of the intermediate hydrogen storage tank and the size of the met Read More
Technical Potential of On-site Wind Powered Hydrogen Producing Refuelling Stations in the Netherlands
Aug 2020
Publication
This study assesses the technical potential of wind turbines to be installed next to existing fuelling stations in order to produce hydrogen. Hydrogen will be used for Fuel Cell Vehicle refuelling and feed-in existing local gas grids. The suitable fuelling stations are selected through a GIS assessment applying buffer zones and taking into account risks associated with wind turbine installation next to built-up areas critical infrastructures and ecological networks. I Read More
Thermodynamic Evaluation of Bi-directional Solid Oxide Cell Systems Including Year-round Cumulative Exergy Analysis
Jun 2018
Publication
Bi-directional solid oxide cell systems (Bi-SOC) are being increasingly considered as an electrical energy storage method and consequently as a means to boost the penetration of renewable energy (RE) and to improve the grid flexibility by power-to-gas electrochemical conversion. A major advantage of these systems is that the same SOC stack operates as both energy storage device (SOEC) and energy producing device (SOFC) based on the energy de Read More
An Innovative Approach for Energy Transition in China? Chinese National Hydrogen Policies from 2001 to 2020
Jan 2023
Publication
To accelerate clean energy transition China has explored the potential of hydrogen as an energy carrier since 2001. Until 2020 49 national hydrogen policies were enacted. This paper explores the relevance of these policies to the development of the hydrogen industry and energy transition in China. We examine the reasons impacts and challenges of Chinese national hydrogen policies through the conceptual framework of Thomas Dye’s policy analysis met Read More
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 Read More
Hydrogen in the Electricity Value Chain
Mar 2019
Publication
Renewable energy sources like solar-PV and wind and the electrification of heating demand lead to more variability in the generation and demand of electricity. The need for flexibility in the electricity supply system e.g. by energy storage will therefore increase. Hydrogen has been a long-serving CO2-free energy carrier apt to store energy over a long period of time without significant losses.
Review and Harmonization of the Life-Cycle Global Warming Impact of PV-Powered Hydrogen Production by Electrolysis
Sep 2021
Publication
This work presents a review of life-cycle assessment (LCA) studies of hydrogen electrolysis using power from photovoltaic (PV) systems. The paper discusses the assumptions strengths and weaknesses of 13 LCA studies and identifies the causes of the environmental impact. Differences in assumptions of system boundaries system sizes evaluation methods and functional units make it challenging to directly compare the Global Warming Potential (GWP) resu Read More
Flexible Power and Biomass-To-Methanol Plants With Different Gasification Technologies
Jan 2022
Publication
The competitiveness of biofuels may be increased by integrating biomass gasification plants with electrolysis units which generate hydrogen to be combined with carbon-rich syngas. This option allows increasing the yield of the final product by retaining a higher amount of biogenic carbon and improving the resilience of the energy sector by favoring electric grid services and sector coupling. This article illustrates a techno-economic comparative analys Read More
Development of a Flashback Correlation for Burner-stabilized Hydrogen-air Premixed Flames
Feb 2022
Publication
With a growing need for replacing fossil fuels with cleaner alternatives hydrogen has emerged as a viable candidate for providing heat and power. However stable and safe combustion of hydrogen is not simple and as such a number of key issues have been identified that need to be understood for a safe design of combustion chambers. One such issue is the higher propensity of hydrogen flames to flashback compared to that for methane flames. The flas Read More
A Comparative Study for H2 –CH4 Mixture Wettability in Sandstone Porous Rocks Relevant to Underground Hydrogen Storage
Mar 2022
Publication
Characterizing the wettability of hydrogen (H2 )–methane (CH4 ) mixtures in subsurface reservoirs is the first step towards understanding containment and transport properties for underground hydrogen storage (UHS). In this study we investigate the static contact angles of H2 –CH4 mixtures in contact with brine and Bentheimer sandstone rock using a captive-bubble cell device at different pressures temperatures and brine salinity values. It is found that un Read More
Overview of First Outcomes of PNR Project HYTUNNEL-CS
Sep 2021
Publication
Dmitry Makarov,
Donatella Cirrone,
Volodymyr V. Shentsov,
Sergii Kashkarov,
Vladimir V. Molkov,
Z. Xu,
Mike Kuznetsov,
Alexandros G. Venetsanos,
Stella G. Giannissi,
Ilias C. Tolias,
Knut Vaagsaether,
André Vagner Gaathaug,
Mark R. Pursell,
Wayne M. Rattigan,
Frank Markert,
Luisa Giuliani,
L.S. Sørensen,
A. Bernad,
Mercedes Sanz Millán,
U. Kummer,
Christian Brauner,
Paola Russo,
J. van den Berg,
F. de Jong,
Tom Van Esbroeck,
M. Van De Veire,
Didier Bouix,
Gilles Bernard-Michel,
Sergey Kudriakov,
Etienne Studer,
Domenico Ferrero,
Joachim Grüne and
G. Stern
The paper presents the first outcomes of the experimental numerical and theoretical studies performed in the funded by Fuel Cell and Hydrogen Joint Undertaking (FCH2 JU) project HyTunnel-CS. The project aims to conduct pre-normative research (PNR) to close relevant knowledge gaps and technological bottlenecks in the provision of safety of hydrogen vehicles in underground transportation systems. Pre normative research performed in the proje Read More
AMHYCO Project - Advances in H2/CO Combustion, Recombination and Containment Modelling
Sep 2023
Publication
During a severe accident in a nuclear power plant one of the potential threats to the containment is the occurrence of energetic combustion events. In modern plants Severe Accident Management Guidelines (SAMG) as well as dedicated mitigation hardware are in place to minimize/mitigate this combustion risk and thus avoid the release of radioactive material into the environment. Advancements in SAMGs are in the focus of AMHYCO an EU-funded H Read More
Investigation of an Intensified Thermo-Chemical Experimental Set-Up for Hydrogen Production from Biomass: Gasification Process Integrated to a Portable Purification System—Part II
Jun 2022
Publication
Biomass gasification is a versatile thermochemical process that can be used for direct energy applications and the production of advanced liquid and gaseous energy carriers. In the present work the results are presented concerning the H2 production at a high purity grade from biomass feedstocks via steam/oxygen gasification. The data demonstrating such a process chain were collected at an innovative gasification prototype plant coupled to a Read More
Hydrogen Related Accidents and Lesson Learned from Events Reported in the East Continental Asia
Sep 2023
Publication
Hydrogen as an energy carrier plays an important role in carbon neutrality and energy transition. Hydrogen is the lightest element with a density of only 0.08375 kg/m3 in gaseous form at standard temperature and pressure (STP); as a result hydrogen is usually stored and transported in a highly compressed form. It is prone to leakage and has a very low ignition energy of 0.017 mJ. Safety remains a challenge in the use of hydrogen as an energy sourc Read More
Maximisation of PV Energy Use and Performance Analysis of a Stand-alone PV-hydrogen System
Sep 2023
Publication
The development of clean hydrogen and photovoltaic (PV) systems is lagging behind the goals set in the Net Zero Emissions scenario of the International Energy Agency. For this reason efficient hydrogen production systems powered from renewable energy need to be deployed faster. This work presents an optimization procedure for a stand-alone fully PVpowered alkaline electrolysis system. The approach is based on the Particle Swarm Optimization Read More
Life Cycle Assessments on Battery Electric Vehicles and Electrolytic Hydrogen: The Need for Calculation Rules and Better Databases on Electricity
May 2021
Publication
LCAs of electric cars and electrolytic hydrogen production are governed by the consumption of electricity. Therefore LCA benchmarking is prone to choices on electricity data. There are four issues: (1) leading Life Cycle Impact (LCI) databases suffer from inconvenient uncertainties and inaccuracies (2) electricity mix in countries is rapidly changing year after year (3) the electricity mix is strongly fluctuating on an hourly and daily basis which requires time-b Read More
Model Supported Business Case Scenario Analysis for Decentral Hydrogen Conversion, Storage and Consumption within Energy Hubs
Mar 2022
Publication
Recently smart energy hubs with hydrogen conversion and storage have received increased attention in the Netherlands. The hydrogen is to be used for vehicle filling stations industrial processes and heating. The scientific problem addressed in this paper is the proper sizing of capacities for renewable energy generation hydrogen conversion and storage in relation to a feasible business case for the energy hub while achieving security of supply. Scenario Read More
Analysis of Hydrogen-powered Propulsion System Alternatives for Diesel-electric Regional Trains
Aug 2022
Publication
Non-electrified regional railway lines with typically employed diesel-electric multiple units require alternative propulsion systems to meet increasingly strict emissions regulations. With the aim to identify an optimal alternative to conventional diesel traction this paper presents a model-based assessment of hydrogen-powered propulsion systems with an internal combustion engine or fuel cells as the prime mover combined with different energy storag Read More
1921–2021: A Century of Renewable Ammonia Synthesis
Apr 2022
Publication
Synthetic ammonia manufactured by the Haber–Bosch process and its variants is the key to securing global food security. Hydrogen is the most important feedstock for all synthetic ammonia processes. Renewable ammonia production relies on hydrogen generated by water electrolysis using electricity generated from hydropower. This was used commercially as early as 1921. In the present work we discuss how renewable ammonia production s Read More
Cost Minimisation of Renewable Hydrogen in a Dutch Neighbourhood While Meeting European Union Sustainability Targets
Jun 2022
Publication
Decentralised renewable energy production in the form of fuels or electricity can have large scale deployment in future energy systems but the feasibility needs to be assessed. The novelty of this paper is in the design and implementation of a mixed integer linear programming optimisation model to minimise the net present cost of decentralised hydrogen production for different energy demands on neighbourhood urban scale while simultaneously adhe Read More
Hydrogen Bubble Growth in Alkaline Water Electrolysis: An Immersed Boundary Simulation Study
Nov 2022
Publication
Enhancing the efficiency of industrial water electrolysis for hydrogen production is important for the energy transition. In electrolysis hydrogen is produced at the cathode which forms bubbles due to the diffusion of dissolved hydrogen in the surrounding supersaturated electrolyte. Hydrogen (and oxygen) bubbles play an important role in the achievable electrolysis efficiency. The growth of the bubbles is determined by diffusive and convective mass transfer. Read More
Ammonia Production from Clean Hydrogen and the Implications for Global Natural Gas Demand
Jan 2023
Publication
Non-energy use of natural gas is gaining importance. Gas used for 183 million tons annual ammonia production represents 4% of total global gas supply. 1.5-degree pathways estimate an ammonia demand growth of 3–4-fold until 2050 as new markets in hydrogen transport shipping and power generation emerge. Ammonia production from hydrogen produced via water electrolysis with renewable power (green ammonia) and from natural gas with CO2 stora Read More
Techno-economic Evaluation on a Hybrid Technology for Low Hydrogen Concentration Separation and Purification from Natural Gas Grid
Jul 2020
Publication
Hydrogen can be stored and distributed by injecting into existing natural grids then at the user site separated and used in different applications. The conventional technology for hydrogen separation is pressure swing adsorption (PSA). The recent NREL study showed the extraction cost for separating hydrogen from a 10% H2 stream with a recovery of 80% is around 3.3e8.3 US$/kg. In this document new system configurations for low hydrogen Read More
Influence of Hydrogen on Grid Investments for Smart Microgrids
Mar 2022
Publication
Electrification of the heat network in buildings together with a rise in popularity of Electric Vehicles (EVs) will result in a need to make investments in the electrical energy infrastructure in order to prevent congestion. This paper discusses the influence of hydrogen in future smart microgrids on these investments. Moreover smart control strategies i.e. EV management and demand response programs are used in this paper to lower the peak of Read More
On the Climate Impacts of Blue Hydrogen Production
Nov 2021
Publication
Natural gas based hydrogen production with carbon capture and storage is referred to as blue hydrogen. If substantial amounts of CO2 from natural gas reforming are captured and permanently stored such hydrogen could be a low-carbon energy carrier. However recent research raises questions about the effective climate impacts of blue hydrogen from a life cycle perspective. Our analysis sheds light on the relevant issues and provides a balanced p Read More
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