Poland
Investigation of Hydrogen Embrittlement Susceptibility and Fracture Toughness Drop after in situ Hydrogen Cathodic Charging for an X65 Pipeline Steel
Apr 2020
Publication
The present research focuses on the investigation of an in situ hydrogen charging effect during Crack Tip Opening Displacement testing (CTOD) on the fracture toughness properties of X65 pipeline steel. This grade of steel belongs to the broader category of High Strength Low Alloy Steels (HSLA) and its microstructure consists of equiaxed ferritic and bainitic grains with a low volume fraction of degenerated pearlite islands. The studied X65 steel specimens were extracted from pipes with 19.15 mm wall thickness. The fracture toughness parameters were determined after imposing the fatigue pre-cracked specimens on air on a specific electrolytic cell under a slow strain rate bending loading (according to ASTM G147-98 BS7448 and ISO12135 standards). Concerning the results of this study in the first phase the hydrogen cations’ penetration depth the diffusion coefficient of molecular and atomic hydrogen and the surficial density of blisters were determined. Next the characteristic parameters related to fracture toughness (such as J KQ CTODel CTODpl) were calculated by the aid of the Force-Crack Mouth Open Displacement curves and the relevant analytical equations.
The Influence of Refractory Metals on the Hydrogen Storage Characteristics of FeTi-based Alloys Prepared by Suspended Droplet Alloying
Jun 2020
Publication
The influence of the addition of refractory metals (molybdenum and tantalum) on the hydrogenation properties of FeTi intermetallic phase-based alloys was investigated. The suspended droplet alloying technique was applied to fabricate FeTiTa-based and FeTiMo-based alloys. The phase composition and hydrogen storage properties of the samples were investigated. The samples modified with the refractory metals exhibited lower plateau pressures and lower hydrogen storage capacities than those of the FeTi reference sample due to solid solution formation. It was observed that the equilibrium pressures decreased with the amount of molybdenum which is in good agreement with the increase in the cell parameters of the TiFe phase. Suspended droplet alloying was found to be a practical method to fabricate alloys with refractory metal additions; however it is appropriate for screening samples with desired chemical and phase compositions rather than for manufacturing purposes.
Hydrogen Explosion Hazards Limitation in Battery Rooms with Different Ventilation Systems
Sep 2019
Publication
When charging most types of industrial lead-acid batteries hydrogen gas is emitted. A large number of batteries especially in relatively small areas/enclosures and in the absence of an adequate ventilation system may create an explosion hazard. This paper describes full scale tests in confined space which demonstrate conditions that can occur in a battery room in the event of a ventilation system breakdown. Over the course of the tests full scale hydrogen emission experiments were performed to study emission time and flammable cloud formation according to the assumed emission velocity. On this basis the characteristics of dispersion of hydrogen in the battery room were obtained. The CFD model Fire Dynamic Simulator (NIST) was used for confirmation that the lack of ventilation in a battery room can be the cause of an explosive atmosphere developing and leading to a potential huge explosive hazard. It was demonstrated that different ventilation systems provide battery rooms with varying efficiencies of hydrogen removal. The most effective type appeared to be natural ventilation which proved more effective than mechanical means.
People’s Attitude to Energy from Hydrogen—From the Point of View of Modern Energy Technologies and Social Responsibility
Dec 2020
Publication
Energy from hydrogen is an appropriate technological choice in the context of sustainable development. The opportunities offered by the use of energy from hydrogen also represent a significant challenge for mobile technologies and daily life. Nevertheless despite a significant amount of research and information regarding the benefits of hydrogen energy it creates considerable controversy in many countries. Globally there is a lack of understanding about the production process of hydrogen energy and the benefits it provides which leads to concerns regarding the consistency of its use. In this study an original questionnaire was used as a research tool to determine the opinions of inhabitants of countries in which hydrogen energy is underutilized and where the infrastructure for hydrogen energy is underdeveloped. Respondents presented their attitude to ecology and indicated their knowledge regarding the operation of hydrogen energy and the use of hydrogen fuel. The results indicate that society is not convinced that the safety levels for energy derived from hydrogen are adequate. It can be concluded that knowledge about hydrogen as an energy source and the production safety and storage methods of hydrogen is very low. Negative attitudes to hydrogen energy can be an important barrier in the development of this energy in many countries.
A Review of Recent Advances on the Effects of Microstructural Refinement and Nano-Catalytic Additives on the Hydrogen Storage Properties of Metal and Complex Hydrides
Dec 2010
Publication
The recent advances on the effects of microstructural refinement and various nano-catalytic additives on the hydrogen storage properties of metal and complex hydrides obtained in the last few years in the allied laboratories at the University of Waterloo (Canada) and Military University of Technology (Warsaw Poland) are critically reviewed in this paper. The research results indicate that microstructural refinement (particle and grain size) induced by ball milling influences quite modestly the hydrogen storage properties of simple metal and complex metal hydrides. On the other hand the addition of nanometric elemental metals acting as potent catalysts and/or metal halide catalytic precursors brings about profound improvements in the hydrogen absorption/desorption kinetics for simple metal and complex metal hydrides alike. In general catalytic precursors react with the hydride matrix forming a metal salt and free nanometric or amorphous elemental metals/intermetallics which in turn act catalytically. However these catalysts change only kinetic properties i.e. the hydrogen absorption/desorption rate but they do not change thermodynamics (e.g. enthalpy change of hydrogen sorption reactions). It is shown that a complex metal hydride LiAlH4 after high energy ball milling with a nanometric Ni metal catalyst and/or MnCl2 catalytic precursor is able to desorb relatively large quantities of hydrogen at RT 40 and 80 °C. This kind of behavior is very encouraging for the future development of solid state hydrogen systems.
Residual Performance of Composite Pressure Vessels Submitted to Mechanical Impacts
Sep 2017
Publication
Type IV pressure vessels are commonly used for hydrogen on-board stationary or bulk storages. During their lifetime they can be submitted to mechanical impacts creating damage within the composite structure not necessarily correlated to what is visible from the outside. When an impact is suspected or when a cylinder is periodically inspected it is necessary to determine whether it can safely stay in service or not. The FCH JU project Hypactor aims at creating a large database of impacts characterized by various non destructive testing (NDT) methods in order to provide reliable pass-fail criteria for damaged cylinders. This paper presents some of the tests results investigating short term burst) and long term (cycling) performance of impacted cylinders and the recommendations that can be made for impact testing and NDT criteria calibration.
Investigation of Praseodymium and Samarium Co-doped Ceria as an Anode Catalyst for DIR-SOFC Fueled by Biogas
Aug 2020
Publication
The Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer.
The XRD SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore the electrical properties of SOFCs with catalytic layers deposited on the Ni-YSZ anode were examined by a current density-time and current density-voltage dependence measurements in hydrogen (24 h) and biogas (90 h). Composition of the outlet gasses was in situ analysed by the FTIR-based unit.
It has been found out that Ce0.9Sm0.1O2-δ and Ce0.8Pr0.05Sm0.15O2-δ catalytic layers show the highest stability over time and thus are the most attractive candidates as catalytic materials in comparison with other investigated lanthanide-doped ceria enhancing direct internal reforming of biogas in SOFCs.
The XRD SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore the electrical properties of SOFCs with catalytic layers deposited on the Ni-YSZ anode were examined by a current density-time and current density-voltage dependence measurements in hydrogen (24 h) and biogas (90 h). Composition of the outlet gasses was in situ analysed by the FTIR-based unit.
It has been found out that Ce0.9Sm0.1O2-δ and Ce0.8Pr0.05Sm0.15O2-δ catalytic layers show the highest stability over time and thus are the most attractive candidates as catalytic materials in comparison with other investigated lanthanide-doped ceria enhancing direct internal reforming of biogas in SOFCs.
Prospects for the Use of Hydrogen in the Armed Forces
Oct 2021
Publication
The energy security landscape that we envisage in 2050 will be different from that of today. Meeting the future energy needs of the armed forces will be a key challenge not least for military security. The World Energy Council’s World Energy Scenarios forecast that the world’s population will rise to 10 billion by 2050 which will also necessitate an increase in the size of the armed forces. In this context energy extraction distribution and storage become essential to stabilizing the imbalance between production and demand. Among the available solutions Power to Hydrogen (P2H) is one of the most appealing options. However despite the potential many obstacles currently hinder the development of the P2H market. This article aims to identify and analyse existing barriers to the introduction of P2H technologies that use hydrogen. The holistic approach used which was based on a literature survey identified obstacles and possible strategies for overcoming them. The research conducted presents an original research contribution at the level of hydrogen strategies considered in leading countries around the world. The research findings identified unresolved regulatory issues and sources of uncertainty in the armed forces. There is a lack of knowledge in the armed forces of some countries about the process of producing hydrogen energy and its benefits which raises concerns about the consistency of its exploitation. Negative attitudes towards hydrogen fuel energy can be a significant barrier to its deployment in the armed forces. Possible approaches and solutions have also been proposed to eliminate obstacles and to support decision makers in defining and implementing a strategy for hydrogen as a clean energy carrier. There are decisive and unresolved obstacles to its deployment not only in the armed forces
Studies of the Impact of Hydrogen on the Stability of Gaseous Mixtures of THT
Dec 2020
Publication
One of the most important requirements concerning the quality of natural gases guaranteeing their safe use involves providing the proper level of their odorization. This allows for the detection of uncontrolled leakages of gases from gas networks installations and devices. The concentration of an odorant should be adjusted in such a manner that the gas odor in a mixture with air would be noticeable by users (gas receivers). A permanent odor of gas is guaranteed by the stability of the odorant molecule and its resistance to changes in the composition of odorized gases. The article presents the results of experimental research on the impact of a hydrogen additive on the stability of tetrahydrothiophene (THT) mixtures in methane and in natural gas with a hydrogen additive. The objective of the work was to determine the readiness of measurement infrastructures routinely used in monitoring the process of odorizing natural gas for potential changes in its composition. One of the elements of this infrastructure includes the reference mixtures of THT used to verify the correctness of the readings of measurement devices. The performed experimental tests address possible changes in the composition of gases supplied via a distribution network resulting from the introduction of hydrogen. The lack of interaction between hydrogen and THT has been verified indirectly by assessing the stability of its mixtures with methane and natural gas containing hydrogen. The results of the presented tests permitted the identification of potential hazards for the safe use of gas from a distribution network resulting from changes in its composition caused by the addition of hydrogen.
Evaluation of Corrosion, Mechanical Properties and Hydrogen Embrittlement of Casing Pipe Steels with Different Microstructure
Dec 2021
Publication
In the research the corrosion and mechanical properties as well as susceptibility to hydrogen embrittlement of two casing pipe steels were investigated in order to assess their serviceability in corrosive and hydrogenating environments under operation in oil and gas wells. Two carbon steels with different microstructures were tested: the medium carbon steel (MCS) with bainitic microstructure and the medium-high carbon steel (MHCS) with ferrite–pearlite microstructure. The results showed that the corrosion resistance of the MHCS in CO2-containing acid chloride solution simulating formation water was significantly lower than that of the MCS which was associated with microstructure features. The higher strength MCS with the dispersed microstructure was less susceptible to hydrogen embrittlement under preliminary electrolytic hydrogenation than the lower strength MHCS with the coarse-grained microstructure. To estimate the embrittlement of steels the method of the FEM load simulation of the specimens with cracks was used. The constitutive relations of the true stress–strain of the tested steels were defined. The stress and strain dependences in the crack tip were calculated. It was found that the MHCS was characterized by the lower plasticity on the stage of the neck formation of the specimen and the lower fracture toughness than the other one. The obtained results demonstrating the limitations of the usage of casing pipes made of the MHCS with the coarse-grained ferrite/pearlite microstructure in corrosive and hydrogenating environments were discussed.
Varying Load Distribution Impacts on the Operation of a Hydrogen Generator Plant
Oct 2021
Publication
This study advances several methods to evaluate the operation of a hydrogen generator plant. The model developed helps customize plants that contain multiple generators of varying powers using a decision module which determines the most efficient plant load distribution. Evaluation indices to assess individual devices within the plant are proposed and system flexibility maximizes the amount of renewable energy stored. Three case studies examined the variable load distribution of an electrolysis system connected to a 40 MW wind farm for energy storage purposes and incorporated a “night-valley” operational strategy. These methods facilitate the selection of the proper plant configuration and provide estimates for individual device effectiveness within the system.
Hydrogen Embrittlement and Oxide Layer Effect in the Cathodically Charged Zircaloy-2
Apr 2020
Publication
Poland The present paper is aimed at determining the less investigated effects of hydrogen uptake on the microstructure and the mechanical behavior of the oxidized Zircaloy-2 alloy. The specimens were oxidized and charged with hydrogen. The different oxidation temperatures and cathodic current densities were applied. The scanning electron microscopy X-ray electron diffraction spectroscopy hydrogen absorption assessment tensile and nanoindentation tests were performed. At low oxidation temperatures an appearance of numerous hydrides and cracks and a slight change of mechanical properties were noticed. At high-temperature oxidation the oxide layer prevented the hydrogen deterioration of the alloy. For nonoxidized samples charged at different current density nanoindentation tests showed that both hardness and Young’s modulus revealed the minims at specific current value and the stepwise decrease in hardness during hydrogen desorption. The obtained results are explained by the barrier effect of the oxide layer against hydrogen uptake softening due to the interaction of hydrogen and dislocations nucleated by indentation test and hardening caused by the decomposition of hydrides. The last phenomena may appear together and result in hydrogen embrittlement in forms of simultaneous hydrogen-enhanced localized plasticity and delayed hydride cracking.
Assessment of Operational Degradation of Pipeline Steels
Jun 2021
Publication
This paper summarizes a series of the authors’ research in the field of assessing the operational degradation of oil and gas transit pipeline steels. Both mechanical and electrochemical properties of steels are deteriorated after operation as is their resistance to environmentally-assisted cracking. The characteristics of resistance to brittle fracture and stress corrosion cracking decrease most intensively which is associated with a development of in-bulk dissipated microdamages of the material. The most sensitive indicators of changes in the material’s state caused by degradation are impact toughness and fracture toughness by the J-integral method. The degradation degree of pipeline steels can also be evaluated nondestructively based on in-service changes in their polarization resistance and potential of the fracture surface. Attention is drawn to hydrogenation of a pipe wall from inside as a result of the electrochemical interaction of pipe metal with condensed moisture which facilitates operational degradation of steel due to the combined action of operating stresses and hydrogen. The development of microdamages along steel texture was evidenced metallographically as a trend to the selective etching of boundaries between adjacent bands of ferrite and pearlite and fractographically by revealing brittle fracture elements on the fracture surfaces namely delamination and cleavage indicating the sites of cohesion weakening between ferrite and pearlite bands. The state of the X52 steel in its initial state and after use for 30 years was assessed based on the numerical simulation method.
Effect of Hydrogen Addition on the Energetic and Ecologic Parameters of an SI Engine Fueled by Biogas
Jan 2021
Publication
The global policy solution seeks to reduce the usage of fossil fuels and greenhouse gas (GHG) emissions and biogas (BG) represents a solutions to these problems. The use of biogas could help cope with increased amounts of waste and reduce usage of fossil fuels. Biogas could be used in compressed natural gas (CNG) engines but the engine electronic control unit (ECU) needs to be modified. In this research a spark ignition (SI) engine was tested for mixtures of biogas and hydrogen (volumetric hydrogen concentration of 0 14 24 33 and 43%). In all experiments two cases of spark timing (ST) were used: the first for an optimal mixture and the second for CNG. The results show that hydrogen increases combustion quality and reduces incomplete combustion products. Because of BG’s lower burning speed the advanced ST increased brake thermal efficiency (BTE) by 4.3% when the engine was running on biogas. Adding 14 vol% of hydrogen (H2 ) increases the burning speed of the mixture and enhances BTE by 2.6% at spark timing optimal for CNG (CNG ST) and 0.6% at the optimal mixture ST (mixture ST). Analyses of the rate of heat release (ROHR) temperature and pressure increase in the cylinder were carried out using utility BURN in AVL BOOST software.
Validation of Selected Optical Methods for Assessing Polyethylene (PE) Liners Used in High Pressure Vessels for Hydrogen Storage
Jun 2021
Publication
A polyethylene (PE) liner is the basic element in high-pressure type 4 composite vessels designed for hydrogen or compressed natural gas (CNG) storage systems. Liner defects may result in the elimination of the whole vessel from use which is very expensive both at the manufacturing and exploitation stage. The goal is therefore the development of efficient non-destructive testing (NDT) methods to test a liner immediately after its manufacturing before applying a composite reinforcement. It should be noted that the current regulations codes and standards (RC&S) do not specify liner testing methods after manufacturing. It was considered especially important to find a way of locating and assessing the size of air bubbles and inclusions and the field of deformations in liner walls. It was also expected that these methods would be easily applicable to mass-produced liners. The paper proposes the use of three optical methods namely visual inspection digital image correlation (DIC) and optical fiber sensing based on Bragg gratings (FBG). Deformation measurements are validated with finite element analysis (FEA). The tested object was a prototype of a hydrogen liner for high-pressure storage (700 bar). The mentioned optical methods were used to identify defects and measure deformations.
A Hybrid Energy Storage System Using Compressed Air and Hydrogen as the Energy Carrier
Feb 2020
Publication
In this paper an innovative concept of an energy storage system that combines the idea of energy storage through the use of compressed air and the idea of energy storage through the use of hydrogen (with its further conversion to synthetic natural gas) has been proposed. The thermal integration of two sub-systems allows for efficient storage of large amounts of energy based on the use of pressure tanks with limited volumes. A thermodynamic assessment of the integrated hybrid system was carried out. For the assumed operation parameters an energy storage efficiency value of 38.15% was obtained which means the technology is competitive with intensively developed pure hydrogen energy storage technologies. The results obtained for the hybrid system were compared to the results obtained for three reference systems each of which uses hydrogen generators. The first is a typical Power-to-H2-to-Power system which integrates hydrogen generators with a fuel cell system. The other two additionally use a compressed air energy storage installation. In the first case the compressed air energy storage system consists of a diabatic system. In the second case the compressed air energy storage system is adiabatic. The article has discussed the disadvantages and advantages of all the analyzed systems.
Magnesium Gasar as a Potential Monolithic Hydrogen Absorbent
Feb 2021
Publication
The study focuses on the aspect of using the structure of gasars i.e. materials with directed open porosity as a potential hydrogen storage. The structure of the tested gasar is composed of a large number of thin open tubular pores running through the entire longitudinal section of the sample. This allows hydrogen to easily penetrate into the entire sample volume. The analysis of pore distribution showed that the longest diffusion path needed for full penetration of the metal structure with hydrogen is about L = 50–70 μm regardless of the external dimensions of the sample. Attempts to hydrogenate the magnesium gasar structure have shown its ability to accumulate hydrogen at a level of 1 wt%. The obtained results were compared with the best result was obtained for the ZK60 alloy after equal channel angular pressing (ECAP) and crushed to a powder form. The result obtained exceeded 4 wt% of hydrogen accumulated in the metal structure at theoretical 6.9 wt% maximum capacity. A model analysis of the theoretic absorption capacity of pure magnesium was also carried out based on the concentration of vacancies in the metal structure. The theoretical results obtained correlate well with experimental data.
The Energy Approach to the Evaluation of Hydrogen Effect on the Damage Accumulation
Aug 2019
Publication
The energy approach for determining the durability of structural elements at high temperature creep and hydrogen activity was proposed. It has been shown that the approach significantly simplifies research compared with the known ones. Approbation of the approach was carried out on the example of determining the indicators of durability of the Bridgman sample under conditions of creep and different levels of hydrogenation of the metal. It was shown that with an increase of hydrogen concentration in the metal from 2 to 10 ppm the durability of the test sample decreased from 22 to 58%.
Tests of the Vehicle’s Powertrain with Hydrogen Fuel Cells at a Low Temperature
Sep 2019
Publication
The article discusses issues related to the operation of fuel cells stack fed with hydrogen at low temperature. The test object was a Toyota Mirai passenger car equipped with this type of powertrain. Tests were carried out in a thermoclimatic chamber at the Cracow University of Technology. They had an initial character and their aim was to evaluate the work of individual subassemblies of the propulsion system including the hydrogen supply system in terms of operational safety.
Impact of Depth on Underground Hydrogen Storage Operations in Deep Aquifers
Mar 2024
Publication
Underground hydrogen storage in geological structures is considered appropriate for storing large amounts of hydrogen. Using the geological Konary structure in the deep saline aquifers an analysis of the influence of depth on hydrogen storage was carried out. Hydrogen injection and withdrawal modeling was performed using TOUGH2 software assuming different structure depths. Changes in the relevant parameters for the operation of an underground hydrogen storage facility including the amount of H2 injected in the initial filling period cushion gas working gas and average amount of extracted water are presented. The results showed that increasing the depth to approximately 1500 m positively affects hydrogen storage (flow rate of injected hydrogen total capacity and working gas). Below this depth the trend was reversed. The cushion gas-to-working gas ratio did not significantly change with increasing depth. Its magnitude depends on the length of the initial hydrogen filling period. An increase in the depth of hydrogen storage is associated with a greater amount of extracted water. Increasing the duration of the initial hydrogen filling period will reduce the water production but increase the cushion gas volume.
Hydrogen Storage in Pure and Boron-Substituted Nanoporous Carbons—Numerical and Experimental Perspective
Aug 2021
Publication
Nanoporous carbons remain the most promising candidates for effective hydrogen storage by physisorption in currently foreseen hydrogen-based scenarios of the world’s energy future. An optimal sorbent meeting the current technological requirement has not been developed yet. Here we first review the storage limitations of currently available nanoporous carbons then we discuss possible ways to improve their storage performance. We focus on two fundamental parameters determining the storage (the surface accessible for adsorption and hydrogen adsorption energy). We define numerically the values nanoporous carbons have to show to satisfy mobile application requirements at pressures lower than 120 bar. Possible necessary modifications of the topology and chemical compositions of carbon nanostructures are proposed and discussed. We indicate that pore wall fragmentation (nano-size graphene scaffolds) is a partial solution only and chemical modifications of the carbon pore walls are required. The positive effects (and their limits) of the carbon substitutions by B and Be atoms are described. The experimental ‘proof of concept’ of the proposed strategies is also presented. We show that boron substituted nanoporous carbons prepared by a simple arc-discharge technique show a hydrogen adsorption energy twice as high as their pure carbon analogs. These preliminary results justify the continuation of the joint experimental and numerical research effort in this field.
Laser Induced Hydrogen Emission from Ethanol with Dispersed Graphene Particles
Apr 2021
Publication
Efficient hydrogen emission from ethanol with disperse graphene foam particles by using a continuous wave infrared laser diode is reported. The products of ethanol dissociation - hydrogen methane and carbon oxide were measured using mass spectrometry. It was found that the most efficient generation of hydrogen was observed when graphene particles were irradiated by a focused laser beam proceeded at the surface of ethanol solution. The process was assisted by intense white light emission resulting from the laser induced multiphoton ionization of graphene combined with the simultaneous emission of hot electrons. The hot electron emission enables the efficient dissociation of ethanol molecules located close to the solution surface with graphene foam particles.
Inhibition of Hydrogen-yielding Dark Fermentation by Ascomycetous Yeasts
May 2018
Publication
Hydrogen-yielding fermentation conducted in bioreactors is an alternative method of hydrogen production. However unfavourable processes can seriously inhibit bio-hydrogen generation during the acidogenic step of anaerobic digestion. Here ascomycetous yeasts were identified as a major factor inhibiting the production of bio-hydrogen by fermentation. Changes in the performance of hydrogen-producing bioreactors including metabolic shift quantitative changes in the fermentation products decreased pH instability of the microbial community and consequently a dramatic drop in bio-hydrogen yield were observed following yeast infection. Ascomycetous yeasts from the genera Candida Kazachstania and Geotrichum were isolated from hydrogen-producing bioreactors. Yeast metabolites secreted into the growth medium showed antibacterial activity. Our studies indicate that yeast infection of hydrogen-producing microbial communities is one of the serious obstacles to use dark fermentation as an alternative method of bio-hydrogen production. It also explains why studies on hydrogen fermentation are still limited to the laboratory or pilot-scale systems.
Functional Model of Power Grid Stabilization in the Green Hydrogen Supply Chain System—Conceptual Assumptions
Dec 2022
Publication
Green hydrogen supply chain includes supply sources production and distribution of hydrogen produced from renewable energy sources (RES). It is a promising scientific and application area as it is related to the problem of instability of power grids supplied with RES. The article presents the conceptual assumptions of the research on the design of a functional multi-criteria model of the stabilization model architecture of energy distribution networks based on a hydrogen energy buffer taking into account the applicable use of hydrogen. The aim of the research was to identify the variables contributing to the stabilization of the operation of distribution networks. The method used to obtain this result was a systematic review of the literature using the technique of in-depth analysis of full-text articles and expert consultations. The concept of a functional model was described as a matrix in two dimensions in which the identified variables were embedded. The first dimension covers the phases of the supply chain: procurement and production along with storage and distribution. The second dimension divides the separate factors into technical economic and logistic. The research was conducted in the context of system optimization from the point of view of the operator of the energy distribution system. As a result of the research several benefits resulting from stabilization using a hydrogen buffer were identified. Furthermore the model may be used in designing solutions stabilizing the operation of power grids in which there are surpluses of electricity produced from RES. Due to the applied multidimensional approach the developed model is recommended for use as it enables the design of solutions in a systemic manner. Due to the growing level of energy obtained from renewable energy sources the issue of stabilizing the energy network is becoming increasingly important for energy network distributors.
Self-ignition of Hydrogen-nitrogen Mixtures During High-pressure Release Into Air
Oct 2015
Publication
This paper demonstrates experimental and numerical study on spontaneous ignition of H2–N2 mixtures during high-pressure release into air through the tubes of various diameters and lengths. The mixtures included 5% and 10% (vol.) N2 addition to hydrogen being at initial pressure in range of 4.3–15.9 MPa. As a point of reference pure hydrogen release experiments were performed with use of the same experimental stand experimental procedure and extension tubes. The results showed that N2 addition may increase the initial pressure necessary to self-ignite the mixture as much as 2.12 or 2.85 – times for 5% and 10% N2 addition respectively. Additionally simulations were performed with use of Cantera code (0-D) based on the ideal shock tube assumption and with the modified KIVA3V code (2-D) to establish the main factors responsible for ignition and sustained combustion during the release.
Hytunnel Project to Investigate the Use of Hydrogen Vehicles in Road Tunnels
Sep 2009
Publication
Hydrogen vehicles may emerge as a leading contender to replace today’s internal combustion engine powered vehicles. A Phenomena Identification and Ranking Table exercise conducted as part of the European Network of Excellence on Hydrogen Safety (HySafe) identified the use of hydrogen vehicles in road tunnels as a topic of important concern. An internal project called HyTunnel was duly established within HySafe to review identify and analyse the issues involved and to contribute to the wider activity to establish the true nature of the hazards posed by hydrogen vehicles in the confined space of a tunnel and their relative severity compared to those posed by vehicles powered by conventional fuels including compressed natural gas (CNG). In addition to reviewing current hydrogen vehicle designs tunnel design practice and previous research a programme of experiments and CFD modelling activities was performed for selected scenarios to examine the dispersion and explosion hazards potentially posed by hydrogen vehicles. Releases from compressed gaseous hydrogen (CGH2) and liquid hydrogen (LH2) powered vehicles have been studied under various tunnel geometries and ventilation regimes. The findings drawn from the limited work done so far indicate that under normal circumstances hydrogen powered vehicles do not pose a significantly higher risk than those powered by petrol diesel or CNG but this needs to be confirmed by further research. In particular obstructions at tunnel ceiling level have been identified as a potential hazard in respect to fast deflagration or even detonation in some circumstances which warrants further investigation. The shape of the tunnel tunnel ventilation and vehicle pressure relief device (PRD) operation are potentially important parameters in determining explosion risks and the appropriate mitigation measures.
Hydrogen-powered Vehicles in Urban Transport Systems – Current State and Development
Mar 2020
Publication
The work is dedicated to the possibility of using hydrogen-powered vehicles in urban transport systems. Due to the need to look for alternative solutions for vehicles with conventional drive in cities hydrogen-powered cars are one of the practical possibilities of realizing the sustainable transport assumptions and independence from oil imports - which is one of the main priorities of the European Union. This paper presents a literature analysis the analysis of the current state and development of use hydrogen-powered vehicles in the world.<br/>The article refers to the possibilities of use hydrogen-vehicles in different ways of mobility: individual vehicles taxis and shared mobility. In addition the author focused on showing the advantages and disadvantages of using hydrogen-powered vehicles in urban transport systems.
Using Hydrogen Reactors to Improve the Diesel Engine Performance
Apr 2022
Publication
This work is aimed at solving the problem of converting diesel power drives to diesel– hydrogen fuels which are more environmentally friendly and less expensive alternatives to diesel fuel. The method of increasing the energy efficiency of diesel fuels has been improved. The thermochemical essence of using methanol as an alternative fuel to increase energy efficiency based on the provisions of thermotechnics is considered. Alternative methanol fuel has been chosen as the initial product for the hydrogen conversion process and its energy value cost and temperature conditions have been taken into account. Calculations showed that the caloric effect from the combustion of the converted mixture of hydrogen H2 and carbon monoxide CO exceeds the effect from the combustion of the same amount of methanol fuel. Engine power and fuel energy were increased due to the thermochemical regeneration of engine exhaust gas heat. An experimental setup was created to study the operation of a converted diesel engine on diesel–hydrogen products. Experimental studies of power and environmental parameters of a diesel engine converted for diesel–hydrogen products were performed. The studies showed that the conversion of diesel engines to operate using diesel– hydrogen products is technically feasible. A reduction in energy consumption was accompanied by an improvement in the environmental performance of the diesel–hydrogen engine working together with a chemical methanol conversion thermoreactor. The formation of carbon monoxide occurred in the range of 52–62%; nitrogen oxides in the exhaust gases decreased by 53–60% according to the crankshaft speed and loading on the experimental engine. In addition soot emissions were reduced by 17% for the engine fueled with the diesel–hydrogen fuel. The conversion of diesel engines for diesel–hydrogen products is very profitable because the price of methanol is on average 10–20% of the cost of petroleum fuel.
Enhanced Production of Hydrogen from Methanol Using Spark Discharge Generated in a Small Portable Reactor
Nov 2021
Publication
An efficient production of hydrogen from a mixture of methanol and water is possible in a spark discharge. In this discharge there is a synergistic effect of high-energy electrons and high temperature interactions which enables an efficient course of endothermic processes such as the production of hydrogen from methanol. The water to methanol molar ratio of 1:1 was kept constant during the study. While the discharge power and feed flow rate were varied from 15 to 55 W and from 0.25 to 2 mol/h respectively which corresponded to the residence time of the reactants in the plasma zone from 58 to 7 ms. The cooled gas mixture contained 56 to 60% of H2. Other gaseous products of the process were CO CO2 and a small amount of CH4. The maximum energy yield was 16.2 mol(H2)/kWh which represents 20% of the theoretical energy yield when the substrates are in a liquid phase.
Operation Analysis of Selected Domestic Appliances Supplied with Mixture of Nitrogen-Rich Natural Gas with Hydrogen
Dec 2021
Publication
This is article presents the results of the testing of the addition of a hydrogen-to-nitrogen-rich natural gas of the Lw group and its influence on the operation of selected gas-fired domestic appliances. The tests were performed on appliances used for the preparation of meals and hot water production for hygienic and heating purposes. The characteristics of the tested gas appliances are also presented. The burners and their controllers with which the tested appliances were equipped were adapted for the combustion of Lw natural gas. The tested appliances reflected the most popular designs for domestic gas appliances in their group used both in Poland and in other European countries. The tested appliances were supplied with nitrogen-rich natural gas of the Lw group and a mixture of this gas with hydrogen at 13.2% content. The article presents the approximate percentage compositions of the gases used during the tests and their energy parameters. The research was focused on checking the following operating parameters and the safety of the tested appliances: the rated heat input thermal efficiency combustion quality ignition flame stability and transfer. The article contains an analysis of the test results referring in detail to the issue of decreasing the heat input of the appliances by lowering the energy parameters of the nitrogen-rich natural gas of the Lw group mixture with a hydrogen addition and how it influenced the thermal efficiency achieved by the appliances. The conclusions contain an explanation regarding among other things how the design of an appliance influences the thermal efficiency achieved by it in relation to the heat input decrease. In the conclusions on the basis of the research results answers have been provided to the following questions: (1) Whether the hydrogen addition to the nitrogen-rich natural gas of the Lw group will influence the safe and proper operation of domestic gas appliances; (2) What hydrogen percentage can be added to the nitrogen-rich natural gas of the Lw group in order for the appliances adapted for combusting it to operate safely and effectively without the need for modifying them?
Integration of Experimental Facilities: A Joint Effort for Establishing a Common Knowledge Base in Experimental Work on Hydrogen Safety
Sep 2009
Publication
With regard to the goals of the European HySafe Network research facilities are essential for the experimental investigation of relevant phenomena for testing devices and safety concepts as well as for the generation of validation data for the various numerical codes and models. The integrating activity ‘Integration of Experimental Facilities (IEF)’ has provided basic support for jointly performed experimental work within HySafe. Even beyond the funding period of the NoE HySafe in the 6th Framework Programme IEF represents a long lasting effort for reaching sustainable integration of the experimental research capacities and expertise of the partners from different research fields. In order to achieve a high standard in the quality of experimental data provided by the partners emphasis was put on the know-how transfer between the partners. The strategy for reaching the objectives consisted of two parts. On the one hand a documentation of the experimental capacities has been prepared and analysed. On the other hand a communication base has been established by means of biannual workshops on experimental issues. A total of 8 well received workshops has been organised covering topics from measurement technologies to safety issues. Based on the information presented by the partners a working document on best practice including the joint experimental knowledge of all partners with regard to experiments and instrumentation was created. Preserving the character of a working document it was implemented in the IEF wiki website which was set up in order to provide a central communication platform. The paper gives an overview of the IEF network activities over the last 5 years.
Numerical Analysis of Detonation Propensity of Hydrogen-air Mixtures with Addition of Methane, Ethane or Propane
Oct 2015
Publication
The detonation propensity of hydrogen-air mixtures with addition of methane ethane or propane in wide range of compositions is analyzed. The analysis concerned the detonation cell width ignition delay time RSB and parameters. Results are presented as a function of hydrogen molar fraction. Computations were performed with the use of three Cantera 2.1.1. scripts in the Matlab R2010b environment. The validated mechanisms of chemical reactions based on data available in the literature were used. Six mechanisms were assessed: GRI-Mech 3.0 LLNL SanDiego Wang POLIMI and AramcoMech. In conclusion the relation between detonation propensity parameters is discussed.
On the Use of Hydrogen in Confined Spaces: Results from the Internal Project InsHyde
Sep 2009
Publication
Alexandros G. Venetsanos,
Paul Adams,
Inaki Azkarate,
A. Bengaouer,
Marco Carcassi,
Angunn Engebø,
E. Gallego,
Olav Roald Hansen,
Stuart J. Hawksworth,
Thomas Jordan,
Armin Keßler,
Sanjay Kumar,
Vladimir V. Molkov,
Sandra Nilsen,
Ernst Arndt Reinecke,
M. Stöcklin,
Ulrich Schmidtchen,
Andrzej Teodorczyk,
D. Tigreat,
N. H. A. Versloot and
L. Boon-Brett
The paper presents an overview of the main achievements of the internal project InsHyde of the HySafe NoE. The scope of InsHyde was to investigate realistic small-medium indoor hydrogen leaks and provide recommendations for the safe use/storage of indoor hydrogen systems. Additionally InsHyde served to integrate proposals from HySafe work packages and existing external research projects towards a common effort. Following a state of the art review InsHyde activities expanded into experimental and simulation work. Dispersion experiments were performed using hydrogen and helium at the INERIS gallery facility to evaluate short and long term dispersion patterns in garage like settings. A new facility (GARAGE) was built at CEA and dispersion experiments were performed there using helium to evaluate hydrogen dispersion under highly controlled conditions. In parallel combustion experiments were performed by FZK to evaluate the maximum amount of hydrogen that could be safely ignited indoors. The combustion experiments were extended later on by KI at their test site by considering the ignition of larger amounts of hydrogen in obstructed environments outdoors. An evaluation of the performance of commercial hydrogen detectors as well as inter-lab calibration work was jointly performed by JRC INERIS and BAM. Simulation work was as intensive as the experimental work with participation from most of the partners. It included pre-test simulations validation of the available CFD codes against previously performed experiments with significant CFD code inter-comparisons as well as CFD application to investigate specific realistic scenarios. Additionally an evaluation of permeation issues was performed by VOLVO CEA NCSRD and UU by combining theoretical computational and experimental approaches with the results being presented to key automotive regulations and standards groups. Finally the InsHyde project concluded with a public document providing initial guidance on the use of hydrogen in confined spaces.
From Coal Ashes to Solid Sorbents for Hydrogen Storage
Jun 2020
Publication
The purpose of this work is the literature review in the field of hydrogen storage in solid sorbents. The best solid sorbents for hydrogen storage were selected with the possibility of synthesis them from coal fly ash. In addition the on-board hydrogen storage analysis was carried out. The review method consists of two parts. The first part based on research questions included types of the best sorbents for hydrogen storage the possibility to obtain them from coal fly ash and practical use in hydrogen storage system on-board. The second part was the selection of publications from The Web of Science and Elsevier Scopus databases and the analysis as well as available reports on the websites at this scope. After searching the relevant articles in the databases abstracts were analysed in terms of the questions asked. The links between references and research were checked. The search procedure was repeated several times. Finally articles with high Impact Factor index published by authors recognized on a global scale were selected for the presented review. The collected information proved that carbon materials are suited to hydrogen storage because of their high porosity large specific surface area and thermal stability. Besides solid sorbents such as zeolites metal-organic frameworks activated carbons or zeolite template carbons can be obtained from coal fly ash. Thanks to silicon aluminium and unburned carbon content fly ash is a good material for the synthesis of hydrogen sorbents. Under cryogenic conditions and high pressure it is possible to adsorb as much as 8.5 wt% of hydrogen. Although the Department of Energy (DOE) requirements for the hydrogen storage system on-board vehicles are not met the review of scientific publications shows that research in this area is developing and better parameters are being obtained.
Production of Hydrogen and Methane from Lignocellulose Waste by Fermentation. A Review of Chemical Pretreatment for Enhancing the Efficiency of the Digestion Process
May 2020
Publication
In Poland lignocellulose wastes constitute about 43% of municipal waste (∼4 417 Gg). Anaerobic and/or dark fermentation are sustainable methods of lignocellulosic waste-management and contribute greatly to ever increasing demand for energy and products. This paper presents the results of the theoretical potential of methane and hydrogen yields from lignocellulosic wastes. Also state-of-the-art methods in the field of lignocellulose fermentation as well as its development and pretreatment are discussed. The main reason for applying pretreatment is the decomposition (decrystallization) of cellulose and hemicellulose and cleavage of polymers into monomers which may be more easily digested by bacteria in DF and AD fermentation processes. At current price levels the cheapest methods are basic and acidic pretreatments. Acidic pretreatment is very efficient (especially using sulfuric acids) solubilizing up to 80% of lignocellulose but strong acids produce inhibitors and are highly corrosive. Alkaline pretreatment is a competitive and even more efficient (>80%) method to acidic pretreatment especially for some rigid materials that acid cannot solubilize. Oxidative pretreatment is usually expensive but can support the sacharisation process by either alkaline or acidic methods; in the case of NMMO efficiency reaching 82%. Ion-liquid pretreatment is selective (almost 100% sacharisation) but very costly and is too expensive for hydrogen production. The last methods can be profitable if some valuable by-products results. An efficient chemical pretreatment should be preceded by physical comminution e.g. mechanical which is the cheapest one.
Mechanical Properties of Gas Main Steels after Long-Term Operation and Peculiarities of Their Fracture Surface Morphology
Feb 2019
Publication
Regularities of steel structure degradation of the “Novopskov-Aksay-Mozdok” gas main pipelines (Nevinnomysskaya CS) as well as the “Gorky-Center” pipelines (Gavrilovskaya CS) were studied. The revealed peculiarities of their degradation after long-term operation are suggested to be treated as a particular case of the damage accumulation classification (scheme) proposed by prof. H.M. Nykyforchyn. It is shown that the fracture surface consists of sections of ductile separation and localized zones of micro-spalling. The presence of the latter testifies to the hydrogen-induced embrittlement effect. However the steels under investigation possess sufficiently high levels of the mechanical properties required for their further safe exploitation both in terms of durability and cracking resistance.
Study of the Effects of Changes in Gas Composition as Well as Ambient and Gas Temperature on Errors of Indications of Thermal Gas Meters
Oct 2020
Publication
Thermal gas meters represent a promising technology for billing customers for gaseous fuels however it is essential to ensure that measurement accuracy is maintained in the long term and in a broad range of operating conditions. The effect of hydrogen addition to natural gas will change the physicochemical properties of the mixture of natural gas and hydrogen. Such a mixture will be supplied through the gas system to consumers including households where the amounts of received gas will be metered. The physicochemical properties of hydrogen including the specific density or viscosity differ significantly from those of the natural gas components such as methane ethane propane nitrogen etc. Therefore it is of utmost importance to establish the impact of the changes in the gas composition caused by the addition of hydrogen to natural gas on the metrological properties of household gas meters including thermal gas meters. Furthermore since household gas meters can be installed outdoors and taking into account the fact that household gas meters are good heat exchangers the influence of ambient and gas temperature on the metrological properties of those meters should be investigated. This article reviews a test bench and a testing method concerning errors of thermal gas meter indicators using air and natural gas including the type containing hydrogen. The indication errors for thermal gas meters using air natural gas and natural gas with an addition of 2% 4% 5% 10% and 15% hydrogen were determined and then subjected to metrological analysis. Moreover the test method and test bench are discussed and the results of tests on the impact of ambient and gas temperatures (-25 ◦C and 55 ◦C respectively) on the errors of indications of thermal gas meters are presented. Conclusions for distribution system operators in terms of gas meter selection were drawn based on the test results.
Sustainable Hydrogen Production by Plasmonic Thermophotocatalysis
Feb 2021
Publication
A vision of hydrogen based economy and clean sustainable fossil fuels-free world inspires the scientific community to put much effort into the development of visible-light-driven photochemistry and efficient solar energy harvesting. The unique features of plasmonic nanomaterials such as capability of significant electric field amplification an extreme local heating generation of high energy charge carriers and broad tunability of optical properties coupled to catalytically active surfaces provide an exciting opportunity for hydrogen production with solar photochemistry. This review sums up recent progress in the development of plasmonic thermophotocatalysis paying particular attention to sustainable production of hydrogen. We approach the subject from a broad bottom-up perspective beginning with the brief description of plasmon-related phenomena and plasmon-assisted photochemistry through the demonstration of various plasmonic nanostructures their synthesis and hydrogen production efficiency ending with the idea of continuous-flow reactors and their future implementation in hydrogen production by plasmonic thermophotocatalysis. Finally we summarize the review and highlight the remaining challenges that have to be faced before the widespread commercialization of this technology.
Hydrogen Production During Direct Cellulose Fermentation by Mixed Bacterial Culture: The Relationship Between the Key Process Parameters Using Response Surface Methodology
Jun 2021
Publication
Dark fermentation is a promising method to produce hydrogen from lignocellulosic biomass. This study assessed the influence of temperature phosphate buffer concentration and substrate concentration on direct hydrogen production form cellulose using response surface methodology. Mixed bacterial culture was successfully enriched on cellulose and used as an inoculum for hydrogen production. The model indicated that the highest cumulative hydrogen production (CHP) of 2.14 L H2/Lmedium could be obtained at 13.5 gcellulose/L 79.5 mM buffer and 32.6 °C. However hydrogen yield is then only 0.58 mol H2/molhexose due to low substrate conversion efficiency (SCE). Simultaneous optimization of CHP and SCE with desirability function approach resulted in the H2 yield of 2.71 ± 0.1 mol H2/molhexose and 93.8 ± 1.8% SCE at 3.35 gcellulose/L 69 mM buffer and 32.9 °C. Phosphate concentration above 80 mM decreased H2 production but had positive effect on cellulose consumption. The bacterial community analysis showed that Ruminiclostridium papyrosolvens was responsible for cellulose hydrolysis. Lachnoclostridium sp. was positively correlated with ethanol production at high phosphate buffer concentration while Caproiciproducens sp. with caproate production at low buffer concentration. The obtained results opens the possibility of simultaneous hydrogen and caproate production from cellulosic substrates.
Aging Effects on Modelling and Operation of a Photovoltaic System with Hydrogen Storage
Jun 2021
Publication
In this work the aging effects on modelling and operation of a photovoltaic system with hydrogen storage in terms of energy production decrease and demand for additional hydrogen during 10 years of the system operation was analysed for the entire energy system for the first time. The analyses were performed with the support of experimental data for the renewable energy system composed of photovoltaic modules fuel cell electrolysers hydrogen storage and hydrogen backup.<br/>It has been found that the total degradation of the analysed system can be described by the proposed parameter – unit additional hydrogen consumption ratio. The results reveal a 33.2–36.2% increase of the unit fuel requirement from an external source after 10 years in reference to the initial condition. Degradation of the components can on the other hand be well described with the unit hydrogen consumption ratio by fuel cell for electricity or the unit electricity consumption ratio by electrolyser for hydrogen production which has been found to vary for the electrolyser in the range of 4.6–4.9% and for the fuel cell stack in the range of 13.4–15.1% during the 10 years of the system operation. The analyses indicate that this value depends on the load profile and PV module types and the system performance decline is non-linear."
Research on the Concept of Hydrogen Supply Chains and Power Grids Powered by Renewable Energy Sources: A Scoping Review with the Use of Text Mining
Jan 2022
Publication
The key direction of political actions in the field of sustainable development of the energy sector and economy is the process of energy transformation (decarbonization) and increasing the share of renewable energy sources (RES) in the supply of primary energy. Regardless of the indisputable advantages RES are referred to as unstable energy sources. A possible solution might be the development of the concept of hydrogen supply chains especially the so-called green hydrogen obtained in the process of electrolysis from electricity produced from RES. The aim of the research undertaken in the article is to identify the scope of research carried out in the area of hydrogen supply chains and to link this research with the issues of the operation of electricity distribution networks powered by RES. As a result of the scoping review and the application of the text-mining method using the IRaMuTeQ tool which includes the analysis of the content of 12 review articles presenting the current research achievements in this field over the last three years (2016–2020) it was established that the issues related to hydrogen supply chains including green hydrogen are still not significantly associated with the problem of the operation of power grids. The results of the conducted research allow formulating recommendations for further research areas.
Models of Delivery of Sustainable Public Transportation Services in Metropolitan Areas–Comparison of Conventional, Battery Powered and Hydrogen Fuel-Cell Drives
Nov 2021
Publication
The development of public transport systems is related to the implementation of modern and low-carbon vehicles. Over the last several years there has been a clear progress in this field. The number of electric buses has increased and the first solutions in the area of hydrogen fuel cells have been implemented. Unfortunately the implementation of these technologies is connected with significant financial expenditure. The goal of the article is the analysis of effectiveness of financial investment consisting in the purchase of 30 new public transport buses (together with the necessary infrastructure–charging stations). The analysis has been performed using the NPV method for the period of 10 years. Discount rate was determined on 4% as recommended by the European Commission for this type of project. It is based on the case study of the investment project carried out by Metropolis GZM in Poland. The article determines and compares the efficiency ratios for three investment options-purchase of diesel-powered battery-powered and hydrogen fuel-cell electric vehicles. The results of the analysis indicate that the currently high costs of vehicle purchase and charging infrastructure are a significant barrier for the implementation of battery-powered and hydrogen fuel-cell buses. In order to meet the transport policy goals related to the exchange of traditional bus stock to more eco-friendly vehicles it is necessary to involve public funds for the purpose of financing the investment activities.
Problems of Hydrogen Doping in the Methane Fermentation Process and of Energetic Use of the Gas Mixture
Jul 2021
Publication
This article discusses the technology for doping hydrogen into the fermenter to increase methane production and the amount of energy in the mixture. Hydrogen doping is anticipated to enable more carbon to be applied to produce methane. Hydrogen is proposed to be produced by using excess electricity from for example off-peak electricity hours at night. The possibilities of using a mixture of hydrogen and biogas for combustion in boilers and internal combustion engines have been determined. It has been proven that the volumetric addition of hydrogen reduces the heat of combustion of the mixture. Problems arising from hydrogen doping during the methane fermentation process have been identified.
Requirements for Hydrogen Resistance of Materials in CI Engine Toxic Substances Powered by Biofuels
Aug 2019
Publication
It has been described the conception of using platinum catalytic layer in multi hole fuel injector atomizer. The catalytic layer has been placed on not working part of atomizer needle. The aim of modification was activation of dehydrogenation reaction paraffin to olefin hydrocarbons with escape hydrogen molecule in CI engine bio fuel. The modification of atomizer with catalytic layer and reaction process leads to the presence of hydrogen and its influence on structural materials properties after the catalysis which requires the high hydrogen and crack resistance of used materials. There is used high speed steel as material. Article describes how hydrogen and combustion gases influence on thermal friction processes on this material. First of all the investigations were conduct 359 engine with biodiesel. During test had been observed nitrogen oxides carbon monoxide and particles emission. The obtained results show that there is possibility to lower toxic substances emission in exhaust gases CI engine powered by biodiesel. On the second it has been described the influence of biodiesel (including hydrogen) on fuel injector components and their influence on structural materials characteristics. There has been presented how biodiesel with hydrogen influences on precision elements and injection and return discharges. The investigation has been made by using engine test bench and fuel injector and pumps test equipment.
Study of the Effect of Addition of Hydrogen to Natural Gas on Diaphragm Gas Meters
Jun 2020
Publication
Power-to-gas technology plays a key role in the success of the energy transformation. This paper addresses issues related to the legal and technical regulations specifying the rules for adding hydrogen to the natural gas network. The main issue reviewed is the effects of the addition of hydrogen to natural gas on the durability of diaphragm gas meters. The possibility of adding hydrogen to the gas network requires confirmation of whether within the expected hydrogen concentrations long-term operation of gas meters will be ensured without compromising their metrological properties and operational safety. Methods for testing the durability of gas meters applied at test benches and sample results of durability tests of gas meters are presented. Based on these results a metrological and statistical analysis was carried out to establish whether the addition of hydrogen affects the durability of gas meters over time. The most important conclusion resulting from the conducted study indicates that for the tested gas meter specimens there was no significant metrological difference between the obtained changes of errors of indications after testing the durability of gas meters with varying hydrogen content (from 0% to 15%).
Thermodynamic, Economic and Environmental Assessment of Renewable Natural Gas Production Systems
May 2020
Publication
One of the options to reduce the dependence on fossil fuels is to produce gas with the quality of natural gas but based on renewable energy sources. It can encompass among other biogas generation from various types of biomass and its subsequent upgrading. The main aim of this study is to analyze under a combined technical economic and environmental perspective three of the most representative technologies for the production of biomethane (bio-based natural gas): (i) manure fermentation and its subsequent upgrading by CO2 removal (ii) manure fermentation and biogas methanation using renewable hydrogen from electrolysis and (iii) biomass gasification in the atmosphere of oxygen and methanation of the resulted gas. Thermodynamic economic and environmental analyses are conducted to thoroughly compare the three cases. For these purposes detailed models in Aspen Plus software were built while environmental analysis was performed using the Life Cycle Assessment methodology. The results show that the highest efficiency (66.80%) and the lowest break-even price of biomethane (19.2 €/GJ) are reached for the technology involving fermentation and CO2 capture. Concerning environmental assessment the system with the best environmental performance varies depending on the impact category analyzed being the system with biomass gasification and methanation a suitable trade-off solution for biomethane production.
Influence of Carbon Catalysts on the Improvement of Hydrogen Storage Properties in a Body-Centered Cubic Solid Solution Alloy
Jun 2021
Publication
Body-centered cubic (BCC) alloys are considered as promising materials for hydrogen storage with high theoretical storage capacity (H/M ratio of 2). Nonetheless they often suffer from sluggish kinetics of hydrogen absorption and high hydrogen desorption temperature. Carbon materials are efficient hydrogenation catalysts however their influence on the hydrogen storage properties of BCC alloy has not been comprehensively studied. Therefore in this paper composites obtained by milling of carbon catalysts (carbon nanotubes mesoporous carbon carbon nanofibers diamond powder graphite fullerene) and BCC alloy (Ti1.5V0.5) were extensively studied in the non-hydrogenated and hydrogenated state. The structure and microstructure of the obtained materials were studied by scanning and transmission electron microscopes X-ray diffraction (XRD) and Raman spectroscopy. XRD and Raman measurements showed that BCC alloy and carbon structures were in most cases intact after the composite synthesis. The hydrogenation/dehydrogenation studies showed that all of the used carbon catalysts significantly improve the hydrogenation kinetics reduce the activation energy of the dehydrogenation process and decrease the dehydrogenation temperature (by nearly 100 K). The superior kinetic properties were measured for the composite with 5 wt % of fullerene that absorbs 3.3 wt % of hydrogen within 1 min at room temperature.
Study of the Microstructural and First Hydrogenation Properties of TiFe Alloy with Zr, Mn and V as Additives
Jul 2021
Publication
In this paper we report the effect of adding Zr + V or Zr + V + Mn to TiFe alloy on microstructure and hydrogen storage properties. The addition of only V was not enough to produce a minimum amount of secondary phase and therefore the first hydrogenation at room temperature under a hydrogen pressure of 20 bars was impossible. When 2 wt.% Zr + 2 wt.% V or 2 wt.% Zr + 2 wt.% V + 2 wt.% Mn is added to TiFe the alloy shows a finely distributed Ti2Fe-like secondary phase. These alloys presented a fast first hydrogenation and a high capacity. The rate-limiting step was found to be 3D growth diffusion controlled with decreasing interface velocity. This is consistent with the hypothesis that the fast reaction is likely to be the presence of Ti2Fe-like secondary phases that act as a gateway for hydrogen.
Assessment of Operational Performance for an Integrated ‘Power to Synthetic Natural Gas’ System
Dec 2021
Publication
This article presents a power to SNG (synthetic natural gas) system that converts hydrogen into SNG via a methanation process. In our analysis detailed models for all the elements of the system are built. We assume a direct connection between a wind farm and a hydrogen generator. For the purposes of our calculations we also assume that the hydrogen generator is powered by the renewable source over a nine-hour period per day (between 21:00 and 06:00) and this corresponds to the off-peak period in energy demand. In addition a hydrogen tank was introduced to maximize the operating time of the methanation reactor. The cooperation between the main components of the system were simulated using Matlab software. The primary aim of this paper is to assess the influence of various parameters on the operation of the proposed system and to optimize its yearly operation via a consideration of the most important constraints. The analyses also examine different nominal power values of renewables from 8 to 12 MW and hydrogen generators from 3 to 6 MW. Implementing the proposed configuration taking into account the direct connection of the hydrogen generator and the methanation reactor showed that it had a positive effect on the dynamics and the operating times of the individual subsystems within the tested configuration
Experimental Determination of Critical Conditions for Hydrogen-air Detonation Propagation in Partially Confined Geometry
Oct 2015
Publication
An experimental investigation was performed to determine critical semi-open channel height (h*) and two-sided open channel width (w*) in which hydrogen-air detonation may propagate. Three types of gaseous mixture composition were used: 25% 29.6% and 40% of hydrogen in air. Experimental setup was based on rectangular (0.11 × 0.11 × 2 m) test channel equipped with acceleration section (0.11 × 0.11 × 1 m). Different channel heights h in range of 15–40 mm and widths w in range of 30–50 mm were used in the test channel. The critical height h* and width w* were defined for each investigated configuration. To determine representative detonation cell sizes λ and to calculate their relationship to h* and w* the sooted plate technique was used. The results showed that detonation in stoichiometric H2-air mixture may propagate in semi-open channel only when the channel height is very close to or higher than approximately 3λ. For less reactive mixtures critical relation h*/λ reaches 3.1 or 3.6 for mixtures with 25% and 40% of hydrogen in air respectively. For two-sided open channel similar relations w*/λ were close to 4.9 and 5.5 for 29.6%H2 and 40%H2 in air respectively.
Experimental Study of Hot Inert Gas Jet Ignition of Hydrogen-Oxygen Mixture
Sep 2005
Publication
Experiments were performed to investigate the diffusion ignition process that occurs when hot inert gas (argon or nitrogen) is injected into the stoichiometric hydrogen-oxygen mixture at the test section. Detonation wave initiated by spark plug in the driver section in stoichiometric acetylene-oxygen mixture At P=0.5 MPa and room temperature propagates as incident shockwave in the driven section through inert gas after bursting the diaphragm separating the sections. At the end wall of driver section the inert gas is heated behind the reflected shock wave and then injected in to the test section with the stoichiometric hydrogen-oxygen mixture through the hole 8mm in diameter. An increase of the initial pressure of the combustible mixture in the test section from 0.2 to 0.6MPa resulted in decrease of the minimum temperature of injected gas causing ignition from 1650K to 850K. At the same time the induction time for ignition process has increased from 190 to 320μs when hot argon was injected. For the injection of hot nitrogen an increase of the initial pressure of the combustible mixture from 0.2 to 0.4 MPa resulted in decrease of the minimum temperature of injected inert gas giving ignition from 1150K to 850Kand an increase of the induction time from 170 to 240μs.The results of experiments indicate that ignition occurs when the static enthalpy of injected mass of inert gas exceeds some critical value. The mechanism of ignition process was also studied by schlieren photography.
An Intercomparison Exercise on the Capabilities of CFD Models to Predict Distribution and Mixing of H2 in a Closed Vessel.
Sep 2005
Publication
This paper presents a compilation and discussion of the results supplied by HySafe partners participating in the Standard Benchmark Exercise Problem (SBEP) V1 which is based on an experiment on hydrogen release mixing and distribution inside a vessel. Each partner has his own point of view of the problem and uses a different approach to the solution. The main characteristics of the models employed for the calculations are compared. The comparison between results together with the experimental data when available is made. Relative deviations of each model from the experimental values are also included. Explanations and interpretations of the results are presented together with some useful conclusions for future work.
An Inter-Comparison Exercise on the Capabilities of CFD Models to Predict the Short and Long Term Distribution and Mixing of Hydrogen in a Garage
Sep 2007
Publication
Alexandros G. Venetsanos,
E. Papanikolaou,
J. García,
Olav Roald Hansen,
Matthias Heitsch,
Asmund Huser,
Wilfried Jahn,
Jean-Marc Lacome,
Thomas Jordan,
H. S. Ledin,
Dmitry Makarov,
Prankul Middha,
Etienne Studer,
Andrei V. Tchouvelev,
Franck Verbecke,
M. M. Voort,
Andrzej Teodorczyk and
M. A. Delichatsios
The paper presents the results of the CFD inter-comparison exercise SBEP-V3 performed within the activity InsHyde internal project of the HYSAFE network of excellence in the framework of evaluating the capability of various CFD tools and modelling approaches in predicting the physical phenomena associated to the short and long term mixing and distribution of hydrogen releases in confined spaces. The experiment simulated was INERIS-TEST-6C performed within the InsHyde project by INERIS consisting of a 1 g/s vertical hydrogen release for 240 s from an orifice of 20 mm diameter into a rectangular room (garage) of dimensions 3.78x7.2x2.88 m in width length and height respectively. Two small openings at the front and bottom side of the room assured constant pressure conditions. During the test hydrogen concentration time histories were measured at 12 positions in the room for a period up to 5160 s after the end of release covering both the release and the subsequent diffusion phases. The benchmark was organized in two phases. The first phase consisted of blind simulations performed prior to the execution of the tests. The second phase consisted of post calculations performed after the tests were concluded and the experimental results made available. The participation in the benchmark was high: 12 different organizations (2 non-HYSAFE partners) 10 different CFD codes and 8 different turbulence models. Large variation in predicted results was found in the first phase of the benchmark between the various modelling approaches. This was attributed mainly to differences in turbulence models and numerical accuracy options (time/space resolution and discretization schemes). During the second phase of the benchmark the variation between predicted results was reduced.
Experimental and Numerical Study on Spontaneous Ignition of Hydrogen-methane Jets in Air
Sep 2013
Publication
This paper is an investigation of the spontaneous ignition process of high-pressure hydrogen and hydrogen-methane mixtures injected into air. The experiments were conducted in a closed channel filled with air where the hydrogen or hydrogen–methane mixture depressurised through different tubes (diameters d = 6 10 and 14 mm and lengths L = 10 25 40 50 75 and 100 mm). The methane addition to the mixture was 5% and 10% vol. The results showed that only 5% methane addition may increase even 2.67 times the pressure at which the mixture may ignite in comparison to the pressure of the pure hydrogen flow. The 10% of methane addition did not provide an ignition for burst pressures up to 15.0 MPa in the geometrical configuration with the longest tube (100 mm). Additionally the simulations of the experimental configuration with pure hydrogen were performed with the use of KIVA numerical code with full kinetic reaction mechanism.
Impact of Hydrogen Injection on Natural Gas Measurement
Dec 2021
Publication
Hydrogen is increasingly receiving a primary role as an energy vector in ensuring the achievement of the European decarbonization goals by 2050. In fact Hydrogen could be produced also by electrolysis of water using renewable sources such as photovoltaic and wind power being able to perform the energy storage function as well as through injection into natural gas infrastructures. However hydrogen injection directly impacts thermodynamic properties of the gas itself such as density calorific value Wobbe index sound speed etc. Consequently this practice leads to changes in metrological behavior especially in terms of volume and gas quality measurements. In this paper the authors present an overview on the impact of hydrogen injection in natural gas measurements. In particular the changes in thermodynamic properties of the gas mixtures with different H2 contents have been evaluated and the effects on the accuracy of volume conversion at standard conditions have been investigated both on the theoretical point of view and experimentally. To this end the authors present and discuss the effect of H2 injection in gas networks on static ultrasonic domestic gas meters both from a theoretical and an experimental point of view. Experimental tests demonstrated that ultrasonic gas meters are not significantly affected by H2 injection up to about 10%.
Fast Turbulent Deflagration and DDT of Hydrogen-Air Mixtures in Small Obstructed Channel
Sep 2007
Publication
An experimental study of flame propagation acceleration and transition to detonation in hydrogen-air mixture in 2 m long rectangular cross section channel filled with obstacles located at the bottom wall was performed. The initial conditions of the hydrogen-air mixture were 0.1 MPa and 293 K. Three different cases of obstacle height (blockage ratio 0.25 0.5 and 0.75) and four cases of obstacle density were studied with the channel height equal to 0.08 m. The channel width was 0.11 m in all experiments. The propagation of flame and pressure waves was monitored by four pressure transducers and four in house ion probes. The pairs of transducers and probes were placed at various locations along the channel in order to get information about the progress of the phenomena along the channel. To examine the influence of mixture composition on flame propagation and DDT the experiments were performed for the compositions of 20% 25% and 29.6% of H2 in air by volume. As a result of the experiments the deflagration and detonation regimes and velocities of flame propagation in the obstructed channel were determined.
Laser-Induced Generation of Hydrogen in Water by Using Graphene Target
Jan 2022
Publication
A new method of hydrogen generation from water by irradiation with CW infrared laser diode of graphene scaffold immersed in solution is reported. Hydrogen production was extremely efficient upon admixing NaCl into water. The efficiency of hydrogen production increased exponentially with laser power. It was shown that hydrogen production was highly efficient when the intense white light emission induced by laser irradiation of graphene foam was occurring. The mechanism of laser-induced dissociation of water is discussed. It was found that hydrogen production was extremely high at about 80% and assisted by a small emission of O2 CO and CO2 gases.
Economic Evaluation of Renewable Hydrogen Integration into Steelworks for the Production of Methanol and Methane
Jun 2022
Publication
This work investigates the cost-efficient integration of renewable hydrogen into steelworks for the production of methane and methanol as an efficient way to decarbonize the steel industry. Three case studies that utilize a mixture of steelworks off-gases (blast furnace gas coke oven gas and basic oxygen furnace gas) which differ on the amount of used off-gases as well as on the end product (methane and/or methanol) are analyzed and evaluated in terms of their economic performance. The most influential cost factors are identified and sensitivity analyses are conducted for different operating and economic parameters. Renewable hydrogen produced by PEM electrolysis is the most expensive component in this scheme and responsible for over 80% of the total costs. Progress in the hydrogen economy (lower electrolyzer capital costs improved electrolyzer efficiency and lower electricity prices) is necessary to establish this technology in the future.
Production of Ultra-dense Hydrogen H(0): A Novel Nuclear Fuel
Mar 2021
Publication
Condensation of hydrogen Rydberg atoms (highly electronically excited) into the lowest energy state of condensed hydrogen i.e. the ultra-dense hydrogen phase H(0) has gained increased attention not only from the fundamental aspects but also from the applied point of view. The physical properties of ultra-dense hydrogen H(0) were recently reviewed summarizing the results reported in 50 publications during the last ten years. The main application of H(0) so far is as the fuel and working medium in nuclear particle generators and nuclear fusion reactors which are under commercial development. The first fusion process showing sustained operation above break-even was published in 2015 (AIP Advances) and used ultra-dense deuterium D(0) as fuel. The first generator giving a high-intensity muon flux intended for muon-catalyzed fusion reactors was patented in 2017 using H(0) as the working medium. Here we first focus on the different nuclear processes using hydrogen isotopes for energy generation and then on the detailed processes of formation of H(0). The production of H(0) employs heterogeneous catalysts which are active in hydrogen transfer reactions. Iron oxide-based alkali promoted catalysts function well but also platinum group metals and carbon surfaces are active in this process. The clusters of highly excited Rydberg hydrogen atoms H(l) are formed upon interaction with alkali Rydberg matter. The final conversion step from ordinary hydrogen Rydberg matter H(l) to H(0) is spontaneous and does not require a solid surface. It is concluded that the exact choice of catalyst is not very important. It is also concluded that the crucial feature of the catalyst is to provide excited alkali atoms at a sufficiently high surface density and in this way enabling formation and desorption of H(0) clusters. Finally the relation to industrial catalytic processes which use H(0) formation catalysts is described and some important consequences like the muon and neutron radiation from H(0) are discussed.
Investigating the Impact of Economic Uncertainty on Optimal Sizing of Grid-Independent Hybrid Renewable Energy Systems
Aug 2021
Publication
One of the many barriers to decarbonization and decentralization of the energy sector in developing countries is the economic uncertainty. As such this study scrutinizes economics of three grid-independent hybrid renewable-based systems proposed to co-generate electricity and heat for a small-scale load. Accordingly the under-study systems are simulated and optimized with the aid of HOMER Pro software. Here a 20-year average value of discount and inflation rates is deemed a benchmark case. The techno-economic-environmental and reliability results suggest a standalone solar/wind/electrolyzer/hydrogen-based fuel cell integrated with a hydrogen-based boiler system is the best alternative. Moreover to ascertain the impact of economic uncertainty on optimal unit sizing of the nominated model the fluctuations of the nominal discount rate and inflation respectively constitute within the range of 15–20% and 10–26%. The findings of economic uncertainty analysis imply that total net present cost (TNPC) fluctuates around the benchmark value symmetrically between $478704 and $814905. Levelized energy cost varies from an amount 69% less than the benchmark value up to two-fold of that. Furthermore photovoltaic (PV) optimal size starts from a value 23% less than the benchmark case and rises up to 55% more. The corresponding figures for wind turbine (WT) are respectively 21% and 29%. Eventually several practical policies are introduced to cope with economic uncertainty.
Why Ultrasonic Gas Leak Detection?
Sep 2021
Publication
Technologies that have traditionally been used in fixed installations to detect hydrogen gas leaks such as Catalytic and Electrochemical Point Sensors have one limitation: in order for a leak to be detected the gas itself must either be in close proximity to the detector or within a pre-defined area. Unfortunately outdoor environmental conditions such as changing wind directions and quick dispersion of the gas cloud from a leaking outdoor installation often cause that traditional gas detection systems may not alert to the presence of gas simply because the gas never reaches the detector. These traditional gas detection systems need to wait for the gas to form a vapor cloud which may or may not ignite and which may or may not allow loss prevention by enabling shutting down the gas facility in time. Ultrasonic Gas Leak Detectors (UGLD) respond at the speed of sound at gas leak initiation unaffected by changing wind directions and dilution of the gas. Ultrasonic Gas Leak Detectors are based on robust microphone technology; they detect outdoor leaks by sensing the distinct high frequency ultrasound emitted by all high pressure gas leaks. With the ultrasonic sensing technology leaking gas itself does not have to reach the sensor – just the sound of the gas leaking. By adding Ultrasonic Gas Leak Detectors for Hydrogen leak detection faster response times and lower operation costs can be obtained.
Improving Ecological Efficiency of Gas Turbine Power System by Combusting Hydrogen and Hydrogen-Natural Gas Mixtures
Apr 2023
Publication
Currently the issue of creating decarbonized energy systems in various spheres of life is acute. Therefore for gas turbine power systems including hybrid power plants with fuel cells it is relevant to transfer the existing engines to pure hydrogen or mixtures of hydrogen with natural gas. However significant problems arise associated with the possibility of the appearance of flashback zones and acoustic instability of combustion an increase in the temperature of the walls of the flame tubes and an increase in the emission of nitrogen oxides in some cases. This work is devoted to improving the efficiency of gas turbine power systems by combusting pure hydrogen and mixtures of natural gas with hydrogen. The organization of working processes in the premixed combustion chamber and the combustion chamber with a sequential injection of ecological and energy steam for the “Aquarius” type power plant is considered. The conducted studies of the basic aerodynamic and energy parameters of a gas turbine combustor working on hydrogen-containing gases are based on solving the equations of conservation and transfer in a multicomponent reacting system. A four-stage chemical scheme for the burning of a mixture of natural gas and hydrogen was used which allows for the rational parameters of environmentally friendly fuel burning devices to be calculated. The premixed combustion chamber can only be recommended for operations on mixtures of natural gas with hydrogen with a hydrogen content not exceeding 20% (by volume). An increase in the content of hydrogen leads to the appearance of flashback zones and fuel combustion inside the channels of the swirlers. For the combustion chamber of the combined-cycle power plant “Vodoley” when operating on pure hydrogen the formation of flame flashback zones does not occur.
Overview of the Hydrogen Production by Plasma-Driven Solution Electrolysis
Oct 2022
Publication
This paper reviews the progress in applying the plasma-driven solution electrolysis (PDSE) which is also referred to as the contact glow-discharge electrolysis (CGDE) or plasma electrolysis for hydrogen production. The physicochemical processes responsible for the formation of PDSE and effects occurring at the discharge electrode in the cathodic and anodic regimes of the PDSE operation are described. The influence of the PDSE process parameters especially the discharge polarity magnitude of the applied voltage type and concentration of the typical electrolytic solutions (K2CO3 Na2CO3 KOH NaOH H2SO4 ) presence of organic additives (CH3OH C2H5OH CH3COOH) temperature of the electrolytic solution the active length and immersion depth of the discharge electrode into the electrolytic solution on the energy efficiency (%) energy yield (g(H2 )/kWh) and hydrogen production rate (g(H2 )/h) is presented and discussed. This analysis showed that in the cathodic regime of PDSE the hydrogen production rate is 33.3 times higher than that in the anodic regime of PDSE whereas the Faradaic and energy efficiencies are 11 and 12.5 times greater respectively than that in the anodic one. It also revealed the energy yield of hydrogen production in the cathodic regime of PDSE in the methanol–water mixture as the electrolytic solution is 3.9 times greater compared to that of the alkaline electrolysis 4.1 times greater compared to the polymer electrolyte membrane electrolysis 2.8 times greater compared to the solid oxide electrolysis 1.75 times greater than that obtained in the microwave (2.45 GHz) plasma and 5.8% greater compared to natural gas steam reforming.
Increasing Technical Efficiency of Renewable Energy Sources in Power Systems
Mar 2023
Publication
This paper presents a method for refining the forecast schedule of renewable energy sources (RES) generation by its intraday adjustment and investigates the measures for reserving RES with unstable generation in electric power systems (EPSs). Owing to the dependence of electricity generation by solar and wind power plants (PV and WPPs respectively) on natural conditions problems arise with their contribution to the process of balancing the power system. Therefore the EPS is obliged to keep a power reserve to compensate for deviations in RES from the planned generation amount. A system-wide reserve (mainly the shunting capacity of thermal and hydroelectric power plants) is used first followed by other means of power reserve: electrochemical hydrogen or biogas plants. To analyze the technical and economic efficiency of certain backup means mathematical models based on the theory of similarity and the criterion method were developed. This method is preferred because it provides the ability to compare different methods of backing up RES generation with each other assess their proportionality and determine the sensitivity of costs to the capacity of backup methods with minimal available initial information. Criterion models have been formed that allow us to build dependencies of the costs of backup means for unstable RES generation on the capacity of the backup means. It is shown that according to the results of the analysis of various methods and means of RES backup hydrogen technologies are relatively the most effective. The results of the analysis in relative units can be clarified if the current and near-term price indicators are known.
Hydrogen Stratification in Enclosures in Dependence of the Gas Release Momentum
Sep 2021
Publication
The hydrogen dispersion phenomenon in an enclosure depends on the ratio of the gas buoyancy induced momentum. Random diffusive motions of individual gas particles become dominative when the release momentum is low. Then a uniform hydrogen concentration appears in the enclosure instead of the gas stratification below the ceiling. The paper justifies this hypothesis by demonstrating fullscale experimental results of hydrogen dispersion within a confined space under six different release variations. During the experiments hydrogen was released into the test room of 60 m3 volume in two methods: through a nozzle and through 21 points evenly distributed on the emission box cover (multipoint release). Each release method was tested with three different hydrogen volume flow rates (3.17·10−3 m3/s 1.63·10−3 m3/s 3.34·10−4 m3/s). The tests confirm the increase of hydrogen convective upward flow and its stratification tendency relative to increased volume flow. A tendency of more uniform hydrogen cloud distribution when Mach Reynolds and Froud number values decreased was demonstrated. Because the hydrogen dispersion phenomena impact fire and explosive hazards the presented experimental results could help fire protection systems be in an enclosure designed allowing their effectiveness optimization.
Hydrogen Internal Combustion Engine Vehicles: A Review
Nov 2022
Publication
Motor vehicles are the backbone of global transport. In recent years due to the rising costs of fossil fuels and increasing concerns about their negative impact on the natural environment the development of low-emission power supply systems for vehicles has been observed. In order to create a stable and safe global transport system an important issue seems to be the diversification of propulsion systems for vehicles which can be achieved through the simultaneous development of conventional internal combustion vehicles electric vehicles (both battery and fuel cell powered) as well as combustion hydrogen-powered vehicles. This publication presents an overview of commercial vehicles (available on the market) powered by internal combustion hydrogen engines. The work focuses on presenting the development of technology from the point of view of introducing ready-made hydrogen-powered vehicles to the market or technical solutions enabling the use of hydrogen mixtures in internal combustion engines. The study covers the history of the technology dedicated hydrogen and bi-fuel vehicles and vehicles with an engine powered by a mixture of conventional fuels and hydrogen. It presents basic technology parameters and solutions introduced by leading vehicle manufacturers in the vehicle market.
Selection of Underground Hydrogen Storage Risk Assessment Techniques
Dec 2021
Publication
The article proposes the use of the analytic hierarchy process (AHP) method to select a risk assessment technique associated with underground hydrogen storage. The initial choosing and ranking of risk assessment techniques can be considered as a multi-criteria decision problem. The usage of a decision model based on six criteria is proposed. A ranking of methods for estimating the risks associated with underground hydrogen storage is presented. The obtained results show that the application of the AHP-based approach may be a useful tool for selecting the UHS risk assessment technique. The proposed method makes it possible to make an objective decision of the most satisfactory approach from the point of view of all the adopted decision criteria regarding the selection of the best risk assessment technique.
Recent Progress on Hydrogen Storage and Production Using Chemical Hydrogen Carriers
Jul 2022
Publication
Depleting fossil fuel resources and anthropogenic climate changes are the reasons for the intensive development of new sustainable technologies based on renewable energy sources. One of the most promising strategies is the utilization of hydrogen as an energy vector. However the limiting issue for large-scale commercialization of hydrogen technologies is a safe efficient and economical method of gas storage. In industrial practice hydrogen compression and liquefaction are currently applied; however due to the required high pressure (30–70 MPa) and low temperature (−253 ◦C) both these methods are intensively energy consuming. Chemical hydrogen storage is a promising alternative as it offers safe storage of hydrogen-rich compounds under ambient conditions. Although many compounds serving as hydrogen carriers are considered some of them do not have realistic perspectives for large-scale commercialization. In this review the three most technologically advanced hydrogen carriers—dimethyl ether methanol and dibenzyltoluene—are discussed and compared. Their potential for industrial application in relation to the energy storage transport and mobility sectors is analyzed taking into account technological and environmental aspects.
Clean Hydrogen Is a Challenge for Enterprises in the Era of Low-Emission and Zero-Emission Economy
Jan 2023
Publication
Hydrogen can be considered an innovative fuel that will revolutionize the energy sector and enable even more complete use of the potential of renewable sources. The aim of the paper is to present the challenges faced by companies and economies that will produce and use hydrogen. Thanks to the use of hydrogen in the energy transport and construction sectors it will be possible to achieve climate neutrality by 2050. By 2050 global demand for hydrogen will increase to 614 million metric tons a year and thanks to the use of hydrogen in energy transport and construction it will be possible to achieve climate neutrality. Depending on the method of hydrogen production the processes used and the final effects several groups can be distinguished marked with different colors. It is in this area of obtaining friendly hydrogen that innovative possibilities for its production open up. The costs of hydrogen production are also affected by network fees national tax systems availability and prices of carbon capture utilization and storage installations energy consumption rates by electrolyzers and transport methods. It is planned that 1 kg of hydrogen will cost USD 1. The study used the desk research method which made it possible to analyze a huge amount of descriptive data and numerical data.
Thermodynamic Analysis of the Effect of Green Hydrogen Addition to a Fuel Mixture on the Steam Methane Reforming Process
Oct 2021
Publication
Steam methane (CH4–H2O) reforming in the presence of a catalyst usually nickel is the most common technology for generating synthesis gas as a feedstock in chemical synthesis and a source of pure H2 and CO. What is essential from the perspective of further gas use is the parameter describing a ratio of equilibrium concentration of hydrogen to carbon monoxide (/ = 2/). The parameter is determined by operating temperature and the initial ratio of steam concentration to methane = 2 0 /4 0 . In this paper the author presents a thermodynamic analysis of the effect of green hydrogen addition to a fuel mixture on the steam methane reforming process of gaseous phase (CH4/H2)–H2O. The thermodynamic analysis of conversion of hydrogen-enriched methane (CH4/H2)–H2O has been performed using parametric equation formalism allowing for determining the equilibrium composition of the process in progress. A thermodynamic condition of carbon precipitation in methane reforming (CH4/H2) with the gaseous phase of H2O has been interpreted. The ranges of substrate concentrations creating carbon deposition for temperature T = 1000 K have been determined based on the technologies used. The results obtained can serve as a model basis for describing the properties of steam reforming of methane and hydrogen mixture (CH4/H2)– H2O.
Studies on the Impact of Hydrogen on the Results of THT Measurement Devices
Dec 2021
Publication
An essential prerequisite for safe transport and use of natural gas is their appropriate odorization. This enables the detection of uncontrolled gas leaks. Proper and systematic odorization inspection ensures both safe use of gas and continuity of the process itself. In practice it is conducted through among others measuring odorant concentrations in gas. Control devices for rapid gas odorization measurements that are currently used on a large scale in the gas industry are equipped with electrochemical detectors selective for sulfur compounds like tetrahydrothiophene (THT). Because the selectivity of electrochemical detector response to one compound (e.g. THT) the available declarations of manufacturers show that detector sensitivity (indirectly also the quality of the measurement result) is influenced by the presence of increased e.g. sulfur or hydrogen compound content in the gas. Because of the lack of sufficient source literature data in this field it was necessary to experimentally verify this impact. The results of studies on experimental verification of suspected influence of increased amounts of hydrogen in gas on the response of electrochemical detector was carried out at the Oil and Gas Institute—National Research Institute (INiG—PIB). They are presented in this article. The data gathered in the course of researching the dependence between THT concentration measurement result quality and hydrogen content in gas composition enabled a preliminary assessment of the threat to the safety of end users of gaseous fuels caused by the introduction of this gas into the distribution network. Noticing the scope of necessary changes in the area of odorization is necessary to guarantee this safety.
A Multiobjective Optimization of a Catalyst Distribution in a Methane/Steam Reforming Reactor Using a Genetic Algorithm
May 2020
Publication
The presented research focuses on an optimization design of a catalyst distribution inside a small-scale methane/steam reforming reactor. A genetic algorithm was used for the multiobjective optimization which included the search for an optimum of methane conversion rate and a minimum of the difference between highest and lowest temperatures in the reactor. For the sake of computational time the maximal number of the segment with different catalyst densities was set to be thirty in this study. During the entire optimization process every part of the reactor could be filled either with a catalyst material or non-catalytic metallic foam. In both cases the porosity and pore size was also specified. The impact of the porosity and pore size on the active reaction surface and permeability was incorporated using graph theory and three-dimensional digital material representation. Calculations start with the generation of a random set of possible reactors each with a different catalyst distribution. The algorithm calls reforming simulation over each of the reactors and after obtaining concentration and temperature fields the algorithms calculated fitness function. The properties of the best reactors are combined to generate a new population of solutions. The procedure is repeated and after meeting the coverage criteria the optimal catalyst distribution was proposed. The paper is summarized with the optimal catalyst distribution for the given size and working conditions of the system.
The Impact of Economic, Energy, and Environmental Factors on the Development of the Hydrogen Economy
Aug 2021
Publication
This article attempts to model interdependencies between socio-economic energy and environmental factors with selected data characterizing the development of the hydrogen economy. The study applies Spearman’s correlation and a linear regression model to estimate the influence of gross domestic product population final energy consumption renewable energy and CO2 emission on chosen hydrogen indicators—production patents energy technology research development and demonstration budgets. The study was conducted in nine countries selected for their actions towards a hydrogen economy based on analyses of national strategies policies research and development programs and roadmaps. The results confirm the statistically significant impact of the chosen indicators which are the drivers for the development of the hydrogen economy from 2008 to 2018. Moreover the empirical results show that different characteristics in each country contribute to the development of the hydrogen economy vision
Investigation on System for Renewable Electricity Storage in Small Scale Integrating Photovoltaics, Batteries, and Hydrogen Generator
Nov 2020
Publication
In this article the solution based on hydrogen generation to increase the flexibility of energy storage systems is proposed. Operating characteristics of a hydrogen generator with integrated electrical energy storage and a photovoltaic installation were determined. The key role of the electricity storage in the proposed system was to maintain the highest operating efficiency related to the nominal parameters of the hydrogen generator. The hydrogen generators achieved the highest energy efficiency for the nominal operating point at the highest power output. Lead-acid batteries were used to ensure the optimal operating conditions for the hydrogen generator supplied with renewable energy throughout the day. The proposed system reduces significantly the hydrogen generator nominal power and devices in system operate in such a way to improve their efficiency and durability. The relations between individual components and their constraints were determined. The proposed solution is fully in-line with previously investigated technologies for improving grid stability and can help incorporate renewable energy sources to increase the sustainability of the energy sector and green hydrogen production.
Magnesium-Based Materials for Hydrogen Storage—A Scope Review
Sep 2020
Publication
Magnesium hydride and selected magnesium-based ternary hydride (Mg2FeH6 Mg2NiH4 and Mg2CoH5) syntheses and modification methods as well as the properties of the obtained materials which are modified mostly by mechanical synthesis or milling are reviewed in this work. The roles of selected additives (oxides halides and intermetallics) nanostructurization polymorphic transformations and cyclic stability are described. Despite the many years of investigations related to these hydrides and the significant number of different additives used there are still many unknown factors that affect their hydrogen storage properties reaction yield and stability. The described compounds seem to be extremely interesting from a theoretical point of view. However their practical application still remains debatable.
Economic Conditions for Developing Hydrogen Production Based on Coal Gasification with Carbon Capture and Storage in Poland
Sep 2020
Publication
This study documents the results of economic assessment concerning four variants of coal gasification to hydrogen in a shell reactor. That assessment has been made using discounting methods (NPV: net present value IRR: internal rate of return) as well as indicators based on a free cash flow to firm (FCFF) approach. Additionally sensitivity analysis has been carried out along with scenario analysis in current market conditions concerning prices of hard coal lignite hydrogen and CO2 allowances as well as capital expenditures and costs related to carbon capture and storage (CCS) systems. Based on NPV results a negative economic assessment has been obtained for all the analyzed variants varying within the range of EUR −903 to −142 million although the variants based on hard coal achieved a positive IRR (5.1–5.7%) but lower than the assumed discount rates. In Polish conditions the gasification of lignite seems to be unprofitable in the assumed scale of total investment outlays and the current price of coal feedstock. The sensitivity analyses indicate that at least a 20% increase of hydrogen price would be required or a similar reduction of capital expenditures (CAPEX) and costs of operation for the best variant to make NPV positive. Analyses have also indicated that on the economic basis only the prices of CO2 allowances exceeding EUR 40/Mg (EUR 52/Mg for lignite) would generate savings due to the availability of CCS systems.
A Comprehensive Overview of Hydrogen-Fueled Internal Combustion Engines: Achievements and Future Challenges
Oct 2021
Publication
This paper provides a comprehensive review and critical analysis of the latest research results in addition to an overview of the future challenges and opportunities regarding the use of hydrogen to power internal combustion engines (ICEs). The experiences and opinions of various international research centers on the technical possibilities of using hydrogen as a fuel in ICE are summarized. The advantages and disadvantages of the use of hydrogen as a solution are described. Attention is drawn to the specific physical chemical and operational properties of hydrogen for ICEs. A critical review of hydrogen combustion concepts is provided drawing on previous research results and experiences described in a number of research papers. Much space is devoted to discussing the challenges and opportunities associated with port and direct hydrogen injection technology. A comparison of different fuel injection and ignition strategies and the benefits of using the synergies of selected solutions are presented. Pointing to the previous experiences of various research centers the hazards related to incorrect hydrogen combustion such as early pre‐ignition late pre‐ignition knocking combustion and backfire are described. Attention is focused on the fundamental importance of air ratio optimization from the point of view of combustion quality NOx emissions engine efficiency and performance. Exhaust gas scrubbing to meet future emission regulations for hydrogen powered internal combustion engines is another issue that is considered. The article also discusses the modifications required to adapt existing engines to run on hydrogen. Referring to still‐unsolved problems the reliability challenges faced by fuel injection systems in particular are presented. An analysis of more than 150 articles shows that hydrogen is a suitable alternative fuel for spark‐ignition engines. It will significantly improve their performance and greatly reduce emissions to a fraction of their current level. However its use also has some drawbacks the most significant of which are its high NOx emissions and low power output and problems in terms of the durability and reliability of hydrogen‐fueled engines.
Hydrogen Dispersion and Ventilation Effects in Enclosures under Different Release Conditions
Apr 2021
Publication
Hydrogen is an explosive gas which could create extremely hazardous conditions when released into an enclosure. Full-scale experiments of hydrogen release and dispersion in the confined space were conducted. The experiments were performed for hydrogen release outflow of 63 × 10−3 m3/s through a single nozzle and multi-point release way optionally. It was found that the hydrogen dispersion in an enclosure strongly depends on the gas release way. Significantly higher hydrogen stratification is observed in a single nozzle release than in the case of the multi-point release when the gas concentration becomes more uniform in the entire enclosure volume. The experimental results were confirmed on the basis of Froud number analysis. The CFD simulations realized with the FDS code by NIST allowed visualization of the experimental hydrogen dispersion phenomenon and confirmed that the varied distribution of hydrogen did not affect the effectiveness of the accidental mechanical ventilation system applied in the tested room.
Energy Futures and Green Hydrogen Production: Is Saudi Arabia Trend?
May 2023
Publication
This paper explores the potential for hydrogen energy to become a future trend in Saudi Arabia energy industry. With the emergence of hydrogen as a promising clean energy source there has been growing interest and investment in this area globally. This study investigated whether the country is likely to pursue this trend given its current energy mix and policies. A study was conducted to provide an overview of the global trends and best practices in hydrogen energy adoption and investment. The outcomes of the analysis show that the country current energy mix has the potential to produce green hydrogen energy. The evaluation of its readiness and potential obstacles for hydrogen energy adoption has been drowned and there are several challenges that need to be addressed. The study outcomes also conclude with policy implications and recommendations for the country energy industry.
Process of Transformation to Net Zero Steelmaking: Decarbonisation Scenarios Based on the Analysis of the Polish Steel Industry
Apr 2023
Publication
The European steel industry is experiencing new challenges related to the market situation and climate policy. Experience from the period of pandemic restrictions and the effects of Russia’s armed invasion of Ukraine has given many countries a basis for including steel along with raw materials (coke iron ore electricity) in economic security products (CRMA). Steel is needed for economic infrastructure and construction development as well as a material for other industries (without steel factories will not produce cars machinery ships washing machines etc.). In 2022 steelmakers faced a deepening energy crisis and economic slowdown. The market situation prompted steelmakers to impose restrictions on production volumes (worldwide production fell by 4% compared to the previous year). Despite the difficult economic situation of the steel industry (production in EU countries fell by 11% in 2022 compared to the previous year) the EU is strengthening its industrial decarbonisation policy (“Fit for 55”). The decarbonisation of steel production is set to accelerate by 2050. To sharply reduce carbon emissions steel mills need new steelmaking technologies. The largest global steelmakers are already investing in new technologies that will use green hydrogen (produced from renewable energy sources). Reducing iron ore with hydrogen plasma will drastically reduce CO2 emissions (steel production using hydrogen could emit up to 95% less CO2 than the current BF + BOF blast furnace + basic oxygen furnace integrated method). Investments in new technologies must be tailored to the steel industry. A net zero strategy (deep decarbonisation goal) may have different scenarios in different EU countries. The purpose of this paper was to introduce the conditions for investing in low-carbon steelmaking technologies in the Polish steel market and to develop (based on expert opinion) scenarios for the decarbonisation of the Polish steel industry.
Sustainable Public Transport Strategies—Decomposition of the Bus Fleet and Its Influence on the Decrease in Greenhouse Gas Emissions
Mar 2022
Publication
The COVID pandemic has caused a major exodus of passengers who chose urban and suburban transport. In many countries especially in the European Union there is a tendency to choose individual means of transport causing damage to the environment and contributing significantly to greenhouse gas emissions. One method to promote urban transport is replacing bus fleets with newer ones thus making public transport more attractive and reducing the emission of harmful exhaust fume components into the atmosphere. The aim of this study was to show a methodology for calculating CO2e for bus fleets. When determining CO2e the principal greenhouse gases such as CO2 CH4 and N2O are usually considered. However CO emissions also have indirect effects on climate through enhanced levels of tropospheric O3 and increased lifetime of CH4; therefore CO2 CH4 N2O and CO emissions were determined for CO2e emission calculations. Two bus fleet variant scenarios were analysed; the first non-investment variant assumed passenger transport using the old fleet without any P&R parking zones. The second scenario was based on the current state which includes the purchase of new low-emission buses and the construction of P&R infrastructure. The calculations were performed using the COPERT emission model with real data from 52 buses running on 13 lines. For the analysed case study of the Rzeszow agglomeration and neighbouring communes implementing the urban and suburban transport modernisation project resulted in a reduction in estimated CO2e emissions of about 450 t. The methodology presented which also considers the impact of CO emissions on the greenhouse effect is a new element of the study that has not been presented in previous works and may serve as a model for other areas in the field of greenhouse gas emission analyses. The future research scope includes investigation of other fuels and powertrain supplies such as hydrogen and hybrid vehicles.
Efficient Use of Low-Emission Power Supply for Means of Transport
Apr 2023
Publication
The paper presents the possibilities of low-emission-powered vehicles based mainly on compressed hydrogen. It shows currently used forms of powering vehicles based on their genesis process of obtention and popularity. They are also compared to each other presenting the advantages and disadvantages of a given solution. The share of electricity in transport its forecasts for the future and the possibilities of combination with conventional energy sources are also described. Based on current technological capabilities hydrogen plays a crucial role as presented in the above work constituting a fundamental basis for future transport solutions.
Towards Sustainable Transport: Techno-Economic Analysis of Investing in Hydrogen Buses in Public Transport in the Selected City of Poland
Dec 2022
Publication
The production storage and use of hydrogen for energy purposes will become increasingly important during the energy transition. One way to use hydrogen is to apply it to power vehicles. This green technological solution affects low-emissions transport which is beneficial and important especially in cities. The authors of this article analyzed the use of hydrogen production infrastructure for bus propulsion in the city of Katowice (Poland). The methods used in the study included a greedy algorithm and cost methods which were applied for the selection of vehicles and identification of the infrastructure for the production storage and refueling of hydrogen as well as to conduct the economic analysis during this term. The article presented the complexity of the techno-economic analysis of the infrastructure and its installation. The key element was the selection of the number of vehicles to the hydrogen production possibilities of an electrolyser and capabilities of the storage and charging infrastructure.
Analysis of the Implementation of Functional Hydrogen Assumptions in Poland and Germany
Nov 2022
Publication
The use of hydrogen exists in various sectors in Poland and Germany. Hydrogen can be used in industry transport decarbonisation of the Polish steel industry and as one of the low-emission alternatives to the existing coal applications in this sector. Limiting climate change requires efforts on a global scale from all countries of the world. Significant economic benefits will be realized by stimulating the development of new technologies to deal with climate change. The scenarios show an increasing demand for industrial hydrogen in the future. The key is to replace gray hydrogen with green and to convert industrial processes which will create additional hydrogen demand. The condition for the development of a green hydrogen economy is access to adequate installed capacity in renewable energy. Germany will become the leading market in the era of energy transformation in the coming years. The implementation of the hydrogen assumptions in Poland is possible to a greater extent by the efforts of entrepreneurs
Massive Green Hydrogen Production Using Solar and Wind Energy: Comparison between Europe and the Middle East
Jul 2023
Publication
This comparative study examines the potential for green hydrogen production in Europe and the Middle East leveraging 3MWp solar and wind power plants. Experimental weather data from 2022 inform the selection of two representative cities namely Krakow Poland (Europe) and Diyala Iraq (Middle East). These cities are chosen as industrial–residential zones representing the respective regions’ characteristics. The research optimizes an alkaline water electrolyzer capacity in juxtaposition with the aforementioned power plants to maximize the green hydrogen output. Economic and environmental factors integral to green hydrogen production are assessed to identify the region offering the most advantageous conditions. The analysis reveals that the Middle East holds superior potential for green hydrogen production compared to Europe attributed to a higher prevalence of solar and wind resources coupled with reduced land and labor costs. Hydrogen production costs in Europe are found to range between USD 9.88 and USD 14.31 per kilogram in contrast to the Middle East where costs span from USD 6.54 to USD 12.66 per kilogram. Consequently the Middle East emerges as a more feasible region for green hydrogen production with the potential to curtail emissions enhance air quality and bolster energy security. The research findings highlight the advantages of the Middle East industrial–residential zone ‘Diyala’ and Europe industrial–residential zone ‘Krakow’ in terms of their potential for green hydrogen production.
A Promising Cobalt Catalyst for Hydrogen Production
Mar 2022
Publication
In this work a metal cobalt catalyst was synthesized and its activity in the hydrogen production process was tested. The substrates were water and ethanol. Activity tests were conducted at a temperature range of 350–600 °C water to ethanol molar ratio of 3 to 5 and a feed flow of 0.4 to 1.2 mol/h. The catalyst had a specific surface area of 1.75 m2/g. The catalyst was most active at temperatures in the range of 500–600 °C. Under the most favorable conditions the ethanol conversion was 97% the hydrogen production efficiency was 4.9 mol (H2)/mol(ethanol) and coke production was very low (16 mg/h). Apart from hydrogen and coke CO2 CH4 CO and traces of C2H2 and C2H4 were formed.
Thermodynamic and Technical Issues of Hydrogen and Methane-Hydrogen Mixtures Pipeline Transmission
Feb 2019
Publication
The use of hydrogen as a non-emission energy carrier is important for the innovative development of the power-generation industry. Transmission pipelines are the most efficient and economic method of transporting large quantities of hydrogen in a number of variants. A comprehensive hydraulic analysis of hydrogen transmission at a mass flow rate of 0.3 to 3.0 kg/s (volume flow rates from 12000 Nm3/h to 120000 Nm3/h) was performed. The methodology was based on flow simulation in a pipeline for assumed boundary conditions as well as modeling of fluid thermodynamic parameters for pure hydrogen and its mixtures with methane. The assumed outlet pressure was 24 bar (g). The pipeline diameter and required inlet pressure were calculated for these parameters. The change in temperature was analyzed as a function of the pipeline length for a given real heat transfer model; the assumed temperatures were 5 and 25 ◦C. The impact of hydrogen on natural gas transmission is another important issue. The performed analysis revealed that the maximum participation of hydrogen in natural gas should not exceed 15%–20% or it has a negative impact on natural gas quality. In the case of a mixture of 85% methane and 15% hydrogen the required outlet pressure is 10% lower than for pure methane. The obtained results present various possibilities of pipeline transmission of hydrogen at large distances. Moreover the changes in basic thermodynamic parameters have been presented as a function of pipeline length for the adopted assumptions.
Electrocatalytic Properties for the Hydrogen Evolution of the Electrodeposited Ni–Mo/WC Composites
May 2021
Publication
The catalytical activity for the hydrogen evolution reaction (HER) of the electrodeposited Ni–Mo/WC composites is examined in 1 M KOH solution. The structure surface morphology and surface composition is investigated using the scanning electron microscopy X-ray diffraction and X-ray photoelectron spectroscopy. The electrocatalytic properties for the HER is evaluated based on the cathodic polarization electrochemical impedance cyclic voltammetry and chronopotentiometry methods. The obtained results prove the superior catalytic activity for the HER of Ni–Mo/WC composites to Ni–Mo alloy. The catalytic activity of Ni–Mo/WC electrodes is determined by the presence of WC nanoparticles and Mo content in the metallic matrix. The best electrocatalytic properties are identified for Ni–Mo/WC composite with the highest Mo content and the most oxidized surface among the studied coatings. The impedance results reveal that the observed improvement in the catalytic activity is the consequence of high real surface area and high intrinsic catalytic activity of the composite.
Hydrogen Technology on the Polish Electromobility Market. Legal, Economic, and Social Aspects
Apr 2021
Publication
The aim of this study was to evaluate the motorization market of electric vehicles powered by hydrogen cells in Poland. European conditions of such technology were indicated as well as original proposals on amendments to the law to increase the development pace of electromobility based on hydrogen cells. There were also presented economic aspects of this economic phenomenon. Moreover survey research was conducted to examine the preferences of hydrogen and electric vehicle users in 5 primary Polish cities. In this way the level of social acceptance for the technological revolution based on hydrogen cells and taking place in the motorization sector was determined.
Catalyst Distribution Optimization Scheme for Effective Green Hydrogen Production from Biogas Reforming
Sep 2021
Publication
Green hydrogen technology has recently gained in popularity due to the current economic and ecological trends that aim to remove the fossil fuels share in the energy mix. Among various alternatives biogas reforming is an attractive choice for hydrogen production. To meet the authorities’ requirements reforming biogas-enriched natural gas and sole biogas is tempting. Highly effective process conditions of biogas reforming are yet to be designed. The current state of the art lacks proper optimization of the process conditions. The optimization should aim to allow for maximization of the process effectiveness and limitation of the phenomena having an adverse influence on the process itself. One of the issues that should be addressed in optimization is the uniformity of temperature inside a reactor. Here we show an optimization design study that aims to unify temperature distribution by novel arrangements of catalysts segments in the model biogas reforming reactor. The acquired numerical results confirm the possibility of the enhancement of reaction effectiveness coming from improving the thermal conditions. The used amount of catalytic material is remarkably reduced as a side effect of the presented optimization. To ensure an unhindered perception of the reaction improvement the authors proposed a ratio of the hydrogen output and the amount of used catalyst as a measure.
Opportunities and Limitations of Hydrogen Energy in Poland against the Background of the European Union Energy Policy
Jul 2022
Publication
One of the strategic goals of developed countries is to significantly increase the share of renewable energy sources in electricity generation. However the process may be hindered by e.g. the storage and transport of energy from renewable sources. The European Union countries see the development of the hydrogen economy as an opportunity to overcome this barrier. Therefore since 2020 the European Union has been implementing a hydrogen strategy that will increase the share of hydrogen in the European energy mix from the current 2 percent to up to 13–14 percent by 2050. In 2021 following the example of other European countries the Polish government adopted the Polish Hydrogen Strategy until 2030 with an outlook until 2040 (PHS). However the implementation of the strategy requires significant capital expenditure and infrastructure modernisation which gives rise to question as to whether Poland is likely to achieve the goals set out in the Polish Hydrogen Strategy and European Green Deal. The subject of the research is an analysis of the sources of financing for the PHS against the background of solutions implemented by the EU countries and a SWOT/TOWS analysis on the hydrogen economy in Poland. The overall result of the SWOT/TOWS analysis shows the advantage of strengths and related opportunities. This allows for a positive assessment of the prospects for the hydrogen economy in Poland. Poland should continue its efforts to take advantage of the external factors (O/S) such as EU support an increased price competitiveness of hydrogen and the emergence of a competitive cross-border hydrogen market in Europe. At the same time the Polish authorities should not forget about the weaknesses and threats that may inhibit the development of the domestic hydrogen market. It is necessary to modernise the infrastructure; increase the share of renewable energy sources in hydrogen production; increase R&D expenditure and in particular to complete the negotiations related to the adoption of the Fit for 55 package.
Co-gasification of Refuse-derived Fuels and Bituminous Coal with Oxygen/steam Blend to Hydrogen Rich Gas
May 2022
Publication
The gasification technology of refuse-derived fuels (RDF) can represent a future alternative to the global hydrogen production and a pathway for the development of the circular economy. The paper presents an innovative way of utilizing RDF through their oxygen/steam co-gasification with bituminous coal to hydrogen rich gas. Five different RDF samples (RDF1÷RDF5) were investigated. The in-depth analyses of the co-gasification of bituminous coal blends with different amounts of RDF (10 15 and 20%w/w) under various temperature conditions were conducted with the application of Hierarchical Clustering Analysis (HCA). The results of the research study revealed a decrease in the total gas yield as well as in the hydrogen yield observed with the increase in the RDF fraction in the fuel blend. The lowest hydrogen yield and the highest carbon conversion were noted for the co-gasification tests of coal blends with 20%w/w for all the studied RDFs. The SEM-EDS (Scanning Electron Microscopy with Energy Dispersive Spectroscopy) and WDXRF (Wavelength Dispersive X-ray Fluorescence) results showed a significantly higher H2 yield in RDF2 co-gasification with coal in comparison with all the remaining RDFs due to the higher concentration of calcium in the sample. The molecular structure analysis of polymers using Fourier transform infrared spectroscopy (FTIR) demonstrated that the most prevalent synthetic polymers in RDF2 are polyethylene terephthalate and polyvinyl chloride characterized by the lowest thermal stability compared to polyethylene and polypropylene.
Modeling the Effects of Implementation of Alternative Ways of Vehicle Powering
Nov 2021
Publication
The trend to replace traditional fossil fuel vehicles is becoming increasingly apparent. The replacement concerns the use of pure biofuels or in blends with traditional fuels the use of hydrogen as an alternative fuel and above all the introduction of electric propulsion. The introduction of new types of vehicle propulsion affects the demand for specific fuels the needs for new infrastructure or the nature of the emissions to the environment generated by fuel production and vehicle operation. The article presents a mathematical model using the difference of two logistic functions the first of which describes the development of the production of a specific type of vehicle and the second the withdrawal of this type of vehicle from traffic after its use. The model makes it possible to forecast both the number of vehicles of each generation as a function of time as well as changes in energy demand from various sources and changes in exhaust emissions. The results of the numerical simulation show replacing classic vehicles with alternative vehicles increases the total energy demand if the generation of the next generation occurs earlier than the decay of the previous generation of vehicles and may decrease in the case of overlapping or delays in the creation of new vehicles compared to the course of the decay function of the previous generation. For electric vehicles carbon dioxide emissions are largely dependent on the emissions from electricity generation. The proposed model can be used to forecast technology development variants as well as analyze the current situation based on the approximation of real data from Vehicle Registration Offices.
The Influence of the First Filling Period Length and Reservoir Level Depth on the Operation of Underground Hydrogen Storage in a Deep Aquifer
Sep 2022
Publication
Underground storage is a method of storing large amounts of renewable energy that can be converted into hydrogen. One of the fundamental problems associated with this process concerns determining the timing and amount of injected gas in the first filling period for the operation of an underground storage facility. Ascertaining the hydrogen flow rate is essential to ensure that the capillary and fracturing pressures are not exceeded. The value of the flow rate was assessed by modelling the injection of hydrogen into a deep aquifer. The best initial H2 injection period was found to be five months. The volume of the cushion gas and the total storage capacity expanded with the extension of the first filling period length. The working capacity grew as the depth increased reaching maximum values at depths of approximately 1200e1400 m. This depth was considered optimal for storing hydrogen in the analysed structure.
The Significance of Formal & Legal Factors in Selecting a Location for a Hydrogen Buffer to Stabilize the Operation of Power Distribution Networks
Oct 2022
Publication
This article presents the conceptual assumptions for the process of identifying and evaluating the formal & legal factors that impact the choice of a hydrogen buffer location to stabilize the operation of power distribution networks. The assumption for the research process was establishing a methodological framework for an in-depth analysis of legislative acts (the EU legislation and the national law) to enable identification of synthetic groups of formal & legal factors to be further analyzed using the DEMATEL method. As a result the cause-and-effect relations between the variables were examined and an in-depth analysis was carried out to investigate the level of impact of the formal & legal factors on the functioning and location of a hydrogen energy buffer.
Energy-Economic Assessment of Islanded Microgrid with Wind Turbine, Photovoltaic Field, Wood Gasifier, Battery, and Hydrogen Energy Storage
Sep 2022
Publication
Island energy systems are becoming an important part of energy transformation due to the growing needs for the penetration of renewable energy. Among the possible systems a combination of different energy generation technologies is a viable option for local users as long as energy storage is implemented. The presented paper describes an energy-economic assessment of an island system with a photovoltaic field small wind turbine wood chip gasifier battery and hydrogen circuit with electrolyzer and fuel cell. The system is designed to satisfy the electrical energy demand of a tourist facility in two European localizations. The operation of the system is developed and dynamically simulated in the Transient System Simulation (TRNSYS) environment taking into account realistic user demand. The results show that in Gdansk Poland it is possible to satisfy 99% of user demand with renewable energy sources with excess energy equal to 31% while in Agkistro Greece a similar result is possible with 43% of excess energy. Despite the high initial costs it is possible to obtain Simple Pay Back periods of 12.5 and 22.5 years for Gdansk and Agkistro respectively. This result points out that under a high share of renewables in the energy demand of the user the profitability of the system is highly affected by the local cost of energy vectors. The achieved results show that the system is robust in providing energy to the users and that future development may lead to an operation based fully on renewables.
Hydrogen as a Renewable Energy Carrier in a Hybrid Configuration of Distributed Energy Systems: Bibliometric Mapping of Current Knowledge and Strategies
Jul 2023
Publication
Storing energy in hydrogen deposits balances the operation of energy systems and is an effective tool in the process of energy transformation towards achieving Sustainable Development Goals. To assess the validity of its use as an alternative renewable energy carrier in dispersed energy systems of hybrid configuration a comprehensive review of scientific literature was conducted in this study based on bibliometric analysis. The bibliographic database used in the study was the international Web of Science database. This review contributes to a better understanding of the characteristics of the selected research area. The evolution of research trends implemented in the design of energy systems associated with hydrogen technologies is revealed clearly indicating that it is a developing field. In recent years there has been an increase in the number of publications although the territorial range of research (mainly simulation) conducted in the domain does not include areas with the most favourable infrastructural conditions. The analysis reveals weak cooperation between South American African East Asian and Oceanic countries. In the light of earlier thematically similar literature reviews several research gaps are also identified and proposals for future research are presented. They concern in particular the parallel implementation and optimization of the operation of hydrogen (HRES—Hybrid Renewable Energy System and HESS—Hybrid Energy Storage System) solutions in terms of economics ecology lifespan and work efficiency as well as their feasibility analysis. With the support of other researchers and those involved in the subject matter this review may contribute to the further development of hybrid hydrogen systems in terms of increasing competitiveness and promoting the implementation of these technologies.
Scaling Factors for Channel Width Variations in Tree-like Flow Field Patterns for Polymer Electrolyte Membrane Fuel Cells - An Experimental Study
Apr 2021
Publication
To have a uniform distribution of reactants is an advantage to a fuel cell. We report results for such a distributor with tree-like flow field plates (FFP). Numerical simulations have shown that the width scaling parameters of tree-like patterns in FFPs used in polymer electrolyte membrane fuel cells (PEMFC) reduces the viscous dissipation in the channels. In this study experimental investigations were conducted on a 2-layer FF plate possessing a tree-like FF pattern which was CNC milled on high-quality graphite. Three FF designs of different width scaling parameters were employed. I–V curves power curves and impedance spectra were generated at 70% 60% and 50% relative humidity (25 cm2 active area) and compared to those obtained from a conventional 1-channel serpentine FF. It was found that the FF design with a width scaling factor of 0.917 in the inlet and 0.925 in the outlet pattern exhibited the best peak power out of the three designs (only 11% - 0.08 W/cm2 lower than reference serpentine FF). Results showed that a reduction of the viscous dissipation in the flow pattern was not directly linked to a PEMFC performance increase. It was found that water accumulation together with a slight increase in single PEMFC resistance were the main reasons for the reduced power density. As further improvements a reduction of the number of branching generation levels and width scaling factor were recommended.
Analysis of the Polish Hydrogen Strategy in the Context of the EU’s Strategic Documents on Hydrogen
Oct 2021
Publication
In December 2019 the European Commission unveiled an ambitious project the European Green Deal which aims to lead the European Union to climate neutrality by 2050. This is a significant challenge for all EU countries and especially for Poland. The role of hydrogen in the processes of decarbonization of the economy and transport is being discussed in many countries around the world to find rational solutions to this difficult and complex problem. There is an ongoing discussion about the hydrogen economy which covers the production of hydrogen its storage transport and conversion to the desired forms of energy primarily electricity mechanical energy and new fuels. The development of the hydrogen economy can significantly support the achievement of climate neutrality. The belief that hydrogen plays an important role in the transformation of the energy sector is widespread. There are many technical and economic challenges as well as legal and logistical barriers to deal with in the transition process. The development of hydrogen technologies and a global sustainable energy system that uses hydrogen offers a real opportunity to solve the challenges facing the global energy industry: meeting the need for clean fuels increasing the efficiency of fuel and energy production and significantly reducing greenhouse gas emissions. The paper provides an in-depth analysis of the Polish Hydrogen Strategy a document that sets out the directions for the development of hydrogen use (competences and technologies) in the energy transport and industrial sectors. This analysis is presented against the background of the European Commission’s document ‘A Hydrogen Strategy for a Climate-Neutral Europe’. The draft project presented is a good basis for further discussion on the directions of development of the Polish economy. The Polish Hydrogen Strategy although it was created later than the EU document does not fully follow its guidelines. The directions for further work on the hydrogen strategy are indicated so that its final version can become a driving force for the development of the country’s economy.
Efficient Plasma Technology for the Production of Green Hydrogen from Ethanol and Water
Apr 2022
Publication
This study concerns the production of hydrogen from a mixture of ethanol and water. The process was conducted in plasma generated by a spark discharge. The substrates were introduced in the liquid phase into the reactor. The gaseous products formed in the spark reactor were hydrogen carbon monoxide carbon dioxide methane acetylene and ethylene. Coke was also produced. The energy efficiency of hydrogen production was 27 mol(H2 )/kWh and it was 36% of the theoretical energy efficiency. The high value of the energy efficiency of hydrogen production was obtained with relatively high ethanol conversion (63%). In the spark discharge it was possible to conduct the process under conditions in which the ethanol conversion reached 95%. However this entailed higher energy consumption and reduced the energy efficiency of hydrogen production to 8.8 mol(H2 )/kWh. Hydrogen production increased with increasing discharge power and feed stream. However the hydrogen concentration was very high under all tested conditions and ranged from 57.5 to 61.5%. This means that the spark reactor is a device that can feed fuel cells the power load of which can fluctuate.
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