Hydrogen Generation Unit Research Articles

An Unprecedented Surprise Failure in a Refinery Hydrogen Generation Unit Jeoparadizing Process Safety and Operational Reliability

Oil and Gas business management started giving focused importance on process safety management in order to ensure sustained operation reliability without any surprise failure incident. Refinery Operation, especially lighter end hydrocarbon processing units are extremely safety critical which need high order reliability from material to maintenance to management perception on plant operation. Routine walk down and specific vigilance especially at hard to reach locations are essential to prevent any eventualities before it becomes too late to control. This paper will discuss about a surprise failure incident at Refinery Hydrogen Generation Unit (HGU) which made the entire refinery management in a state of “raised eyebrow” shock. The consequence of the failure is not only HGU shutdown but simultaneous outage of all critical units which needs hydrogen to operate leading to an unexpected and unaccounted business loss as well HSE impacts.

An intelligent data-driven investigation and optimization integrated with an eco-friendly thermal design approach for a marine diesel engine to study its waste-to-liquefied hydrogen generation potential

The waste heat generated by vehicles, especially heavy-duty engines, has motivated the current research to propose a novel thermal design for a ship's engine. Hence, the suggested system comprises an organic-flash power plant, a bi-evaporator cooling subsystem, a thermal desalination cycle, a water electrolysis-based hydrogen generation unit, and a Claude unit for liquefying hydrogen. The innovative aspects associated with the proposed design include utilizing a novel cascade heat recovery process aimed at reduced irreversibility for the engine's waste and the integration of bi-evaporator technology and Claude unit to facilitate the process of waste-to-liquefied hydrogen generation for a marine engine for improved handling. In addition, the research includes an intelligent study that comprehensively analyzes and optimizes the proposed system in terms of long-term sustainability and economic feasibility. For this purpose, a data-driven optimization technique is implemented using artificial neural networks in combination with multi-objective grey wolf optimization. The aims of the research encompass the optimization of the sustainability index and unit cost of liquefied hydrogen. The research findings indicate that the vapor generator’s terminal temperature difference exerts the most substantial influence on performance metrics, as evidenced by a mean sensitivity index of 0.368. Also, the mentioned objective functions exhibit values of 1.139 and 7.60 $/kg, respectively. Besides, the optimum exergy destruction rate is 124.3 kW, the total investment cost rate is 4.94 $/year, the specific cost of products is 74.87 /GJ, the payback period is 2.2 years, and the net present value is 7.48 M$.

Energy, exergy, economic, and life cycle environmental analysis of a novel biogas-fueled solid oxide fuel cell hybrid power generation system assisted with solar thermal energy storage unit

Biogas production and its derived hydrogen production technology have broad application prospects. In this paper, an integrated biogas power generation system with solid oxide fuel cells is proposed, which mainly consists of four units: a solar thermal energy storage unit, a biogas production and hydrogen generation unit, a SOFC-MGT unit, and a waste heat utilization unit. The presented system is first studied using energy, exergy, economic, and life cycle environmental analyses and the survey results are contrasted with those of renewable energy systems discussed in the references. Besides, a parametric study is conducted to explore the effect of thermodynamic parameters of solar irradiance, ambient temperature, work fluid temperature, reforming temperature, inlet H2O/CH4 ratio of the reformer, and the current density of SOFC. Results indicate that the proposed system's energy efficiency, exergy efficiency, electric power output and exergy destruction are 43.29%, 37.4%, 414.16 kW (net power generation is 351.43 kW) and 1434.59 kW, respectivily. Moreover, the system's levelized cost of electricity and carbon emission factor are $0.076/kWh and 335.6gCO2eq/kWh, having good economic and environmental benefits simultaneously. The parametric study shows that PTSC can be designed shorter with more solar irradiance and high ambient temperature. Besides, the increase of inlet H2O/CH4 ratio and reforming temperature make the system's energy efficiency fall by 2.5% and 20%. For every 300 A/m2 increase in the current density of SOFC, the system efficiency rises by 1.01%.

Development and assessment of a newly developed renewable energy-based hybrid system with liquid hydrogen storage for sustainable development

One of the most effective ways to address the environmental issues triggered by fossil fuels is through the use of renewable energy. In this study, clean and sustainable power and hydrogen generation with three renewable energy sources, a wind-solar-geothermal assisted hybrid plant is planned, investigated, and analyzed. An exhaustive thermodynamic performance analysis is executed to specify the system efficiency by the way energy and exergy efficiency methods. Moreover, this developed cycle comprises a solar photovoltaic (PV) unit, a triple flash geothermal power plant, wind turbines for power generation, and a hydrogen generation and liquefaction unit. Additionally, a case study for Isparta is conducted using actual data on wind speed and solar radiation. A parametric analysis, on the other hand, is conducted to figure out the consequences of the examined cycle's performance. In light of the examination outcomes, the developed plant's power rate is figured as 9942 kW. The hydrogen generation rate and sustainability index are also figured out as 0.02143 kg/s and 2.003, respectively. Finally, the proposed hybrid cycle encloses an energetic and exergetic performance of 32.755 % and 50.06 %, respectively.

An innovative study on a geothermal based multigeneration plant with transcritical CO2 cycle: Thermodynamic evaluation and multi-objective optimization

Renewable energy-sourced integrated plants are among the novel and interesting technologies for production of the clean and effective beneficial multiple commodities. Also, these technologies are one of the main motivations for overcoming environmental troubles. The newly designed geothermal-based multigeneration plant deals with clean and sustainable power, hydrogen, cooling, and heating generation and then comprehensive thermodynamic and economic analyses. This system is driven by a geothermal source that includes a transcritical CO2 based Rankine cycle, an ejector cooling cycle, a hydrogen generation and compression unit, and a domestic hot water preparation unit. Here, a comprehensive mathematical modeling is discussed that are energy and exergy efficiency methods along with economic cost evaluation. Furthermore, to define the optimal working conditions, a multiobjective optimization method is fulfilled based on the relationship between the developed multigeneration system's cost and exergy efficiency. Additionally, a comprehensive parametric assessment is implemented to describe how effects of various indicators on the developed model’s efficiency. In outlook of these outcomes, it is crystal clear that the quantity of clean power and hydrogen generation rate is 1283 kW and 0.009374 kgs−1, respectively. The energy and exergy efficiencies of the developed MG cycle are figured as 27.60% and 22.56%, at 152 ℃ geothermal source temperature. the optimal plant total cost rate is computed as 80.48 $h−1. Finally, it is concluded that this proposed system's performance and cost rates are compatible and applicable.

PVT integrated hydrogen production with small-scale transcritical power cycle

The objective of the present research is to examine the performance of an integrated hydrogen generation system based on solar power. The system is comprised of photovoltaic-thermal (PVT) panels, a transcritical Rankine cycle (tRC), and a hydrogen generation unit, namely proton exchange membrane electrolysis (PEME) process. Carbon dioxide (CO2), which is an environmentally friendly fluid, is used as the working fluid of tRC, where it is directly heated up in the PVT collector. To perform the performance assessment of the system, first, a dynamic simulation of the PVT is conducted based on data from August 17 of Izmir. After, energy and exergy analyses of the integrated system are carried out, followed by parametric analyses. According to the results, the maximum power obtained from the PVT is found to be 2.6 kW, the net energy generated from tRC is calculated as 0.8 kW, while the maximum H2 generation rate is 16 g/h.

Prospects for hydrogen production by the method of gasification of MSW at operating TPPs

The work is devoted to the development of a thermal scheme for the conversion of a cogeneration power plant to threegeneration with the production of hydrogen as a new product.The purpose of the work is to assess the possibility and potential of hydrogen production from MSW at the existing thermal power plants of St. Petersburg.To achieve this goal, it is necessary to develop a methodology for selecting the site of an existing thermal power plant in order to integrate a hydrogen production complex by the MSW gasification method, as well as a methodology for estimating the amount of hydrogen that can potentially be obtained from a given amount of MSW. The research methods include simulation of the thermal circuit of a steam power plant in the United Cycle program.The paper proposes an algorithm for selecting the site of an operating thermal power plant for the integration of a complex for the production of hydrogen by the method of MSW gasification. The algorithm can be applied to any subjects of the Russian Federation, and its relevance is confirmed by strategic documents. Potential locations for the new TPP are being considered in the territories of TPP-21 and TPP-22, which have the necessary resources and good infrastructure. As a result of the study, the site of TPP-22 was selected as the most suitable for the placement of new facilities.A new thermal scheme of a threegeneration power plant has been developed, including a hydrogen generation unit by the MSW gasification method. This allows the production of hydrogen in parallel with the production of electricity and heat. The efficiency evaluation criterion is the fuel heat utilization factor (FHUF). Regardless of the hydrogen content in the generated synthesis gas, the integration of the synthesis gas cooler into the thermal circuit of the TPP leads to an increase in the FHUF and an additional energy effect. This scheme increases the efficiency of existing TPP plants, regardless of the morphological composition of municipal solid waste.

Multi-objective optimization configuration of wind-solar coupling hydrogen production system

The existing research on the wind solar coupling hydrogen generation system lacks the evaluation of factors such as the reliability of power supply to the microgrid system. This paper establishes a multi-objective optimization configuration model of wind-solar coupling hydrogen generation system under grid-connected operation mode for hydrogen generation. From the perspective of system economy and stability analysis, the model optimizes the capacity of the wind power unit, photovoltaic unit, energy storage unit, and hydrogen generation unit to improve the economy and reliability of microgrid operation, to minimize load loss rate, system annual cost, renewable energy power generation loss rate, and energy surplus rate.

Performance of hydrogen and power co-generation system based on chemical looping hydrogen generation of coal

An integrated hydrogen and power co-generation system based on slurry-feed coal gasification and chemical looping hydrogen generation (CLH) was proposed with Shenhua coal as fuel and Fe 2 O 3 /MgAl 2 O 4 as an oxygen carrier. The sensitivity analyses of the main units of the system were carried out respectively to optimize the parameters. The syngas can be converted completely in the fuel reactor, and both of the fuel reactor and steam reactor can maintain heat balance. The purity of hydrogen produced after water condensation is 100%. The energy and exergy analyses of the proposed system were studied. Pinch technology was adopted to get a reasonable design of the heat transfer network, and it is found pinch point appears at the hot side temperature of 224.7 °C. At the given status of the proposed system, the hydrogen yield is 1040.11 kg·h −1 and the CO 2 capture rate is 94.56%. At the same time, its energy and exergy efficiencies are 46.21% and 47.22%, respectively. According to exergy analysis, the degree of exergy destruction is ranked. The gasifier unit has the most serious exergy destruction, followed by chemical looping hydrogen generation unit and the heat recovery steam generator unit. • A hydrogen and power co-generation system is proposed and simulated. • Slurry-coal gasification is integrated with chemical looping hydrogen and combined cycle. • Assessing hydrogen production based on chemical looping conversion of fossil fuels. • Pure hydrogen can be achieved with high carbon capture efficiency through process integration.

Techno-Economic Study of the Potential for Green Hydrogen Production in Egypt

Green hydrogen (GH) is considered one of the best environmental alternatives fuel in the coming decades. GH is produced from natural solar energy and water resources. Although water is available in most countries, but sun is restricted in some regions along the year. Electrolysis process has a potential technology for clean and sustainable source of energy. It is also the best alternative to produce valuable hydrogen fuel (HF) from solar energy. The current study presents a theoretical analysis of designing a small-scale hydrogen generation unit containing two electrolyzers with 100 cells and 40 cm plate diameter to produce 75 kgH2/day with consumed electric energy of 3360 kWh and 675 liter water/day, respectively. For designing a large-scale hydrogen generation plant with 280 ton/day (102,200 ton/year), the required electric power can be estimated as 618,333 kW (618.3 MW). Consequently; the electric energy consumption in MWh required can be estimated as 14,840 MWh and the required daily water consumed in m3/day can be estimated as 2,520 m3/day. Considering the price of 1.0 kg of GH equals 3 USD, the cash flow diagram, showed that the project can recover the invested budget (2,259,390,903 USD) within 8 years and earn a remarkable profit of 5,115,728,534 USD after 25 years. This means that the investment in green hydrogen production projects is highly profitable as hydrogen can be sold as direct fuel, energy carrier or to be reacted with nitrogen to produce green ammonia where can be utilized as fertilizers and other useful industrial applications

Further study on carbon fixation using green power for a solar-assisted multi-generation system with carbon capture

For carbon-based thermal systems, a serious challenge to achieving carbon neutralization is carbon emission reduction. Currently, advanced chemical looping combustion can help thermal systems to realize carbon capture without energy consumption. This study further develops the carbon fixation process of thermal systems using green power. In detail, hydrogen generation and methanol synthesis units are integrated into a multi-generation system, which follows the principle of energy quality matching. Green power, solar heat, methane, high- and low-temperature heat, and mechanical work are reasonably utilized in hydrogen generation, preheating reactants, methanol synthesis, and purifying methanol. The case study shows that the proposed system’s exergy efficiency is enhanced by 10 % compared with the reference system. In addition, about 43 % of carbon dioxide is stored in the form of methanol without cutting down the performance of system components. The energy and exergy efficiencies in the methanol synthesis are 56.36 % and 75.66 %, respectively, indicating the advantages of the proposed system over those proposed in extant research. In addition, these efficiencies are still higher than 50 % and 75 %, respectively, when the incident radiance is larger than 600 W/m2. This study also investigates the effect of electrolytic cell stack and incident irradiance on system performance. Results indicate that the proposed system can directly utilize fluctuating green power without using expensive batteries; moreover, the irreversibility of the multi-generation system is improved. These findings not only broaden the scope of application of green power but also allow to further realize the clean and efficient utilization of fossil fuels.

Comprehensive techno-economic investigation of biomass gasification and nanomaterial based SOFC/SOEC hydrogen production system

This work handled the hydrogen generation by steam-based sawdust gasification procedure. Furthermore, it examined hydrogen generation requirements through conducting thorough parametric examinations concerning parameters that influence hydrogen generation efficiency. Through the integration of the hydrogen generation unit in the newly installed plant, the amount of generated hydrogen had been studied by integrating the solid oxide fuel cell and solid oxide electrolysis cell and relying on the steam gasification of sawdust as biomass. To assess the performance of this new system, a thorough investigation employing thermodynamic and thermoeconomic analyses, and parametric assessments are conducted. Outcomes documented that the maximum destroyed exergy happened in the integrated nanomaterial-based SOFC/SOEC subsystem. The system's exergetic efficiency including hydrogen efficiency rose from 64 to 77%. Also, relying on the thermoeconomic model, the yield of the system's net generated hydrogen improved by about 3%, reducing the unit cost of hydrogen to 0.21 $/kWh from 0.26 $/kWh.

Comparative analyses of a novel solar tower assisted multi-generation system with re-compression CO2 power cycle, thermoelectric generator, and hydrogen production unit

In the present paper, a new energy generation system is suggested for multiple outputs, including a hydrogen generation unit. The plant is powered by a solar tower and involves six different subsystems; supercritical carbon dioxide (sCO2) re-compression Brayton cycle, ammonia-water absorption refrigeration cycle, hydrogen generation, steam generation, drying process, and thermoelectric generator. The thermodynamic assessment of the multi-generation system is carried out for three different cities from Turkey, Iran, and Qatar. The energy and exergy efficiencies are calculated for base conditions to compare the different locations. The operating output parameters for the suggested system and simple re-compression Brayton system are compared. A parametric analysis is also done for investigating the influences of different system variables on plant performance. According to the results, Doha city is found to be more effective due to its geographical conditions. Moreover, based on the comparative study, the proposed cycles produce more power than the basic re-compression cycle with 64.59 kW, 47.33 kW, and 52.25 kW for Doha, Isparta, and Tehran, respectively. Additionally, the analyses revealed that in the term of energy efficiency, the suggested system has 32.29%, 32.28%, and 32.29% better performance than the simple cycle, and in terms of exergy efficiency, it has 4%, 4.8%, and 5% better performance than the simple cycle in Doha, Isparta, and Tehran, respectively.

Techno-economic evaluation and parametric study of generating green hydrogen from waste heat recovery of efficient solid oxide fuel cell

According to the United Nations Population Division, the world population is expanding, and this rise has been more pronounced in the last century. As an instance, the population in 2020 is almost two times more than the population in 1970. As a result, the population will have increased by around 4.1 billion people in 50 years (according to Worldometers.info). Energy may be considered to be one of the most fundamental prerequisites for human survival. This research presents a newly projected energy system based on FC and RR-ORC and PEME for green generation on hydrogen and power. The system actually has two power blocks and one hydrogen generation unit. The system has three subsystems that are modeled incomplete form based on the thermodynamic and economic model. The effect of strategic proposal variables are foreseen on the LCOE, overall cost, and exergetic efficiency. Also, the variation of hydrogen production and net power output is predicted. The results show that current density, as well as fuel and air utilization factor, has a crucial effect on the system performance while the parameters of the bottoming cycle as ORC and pinch point variables have little effect on cycle performance; on the other hand, they affect the downstream cycles much, like hydrogen production system. Increasing current density has the highest effect on the system performance by an 8% reduction in exergy efficiency.

Thermodynamic assessment of a novel multigenerational power system for liquid hydrogen production

A Brayton plant-based multigenerational system is proposed and investigated thermodynamically through energetic and exergetic approaches in this study. Liquid hydrogen, electrical energy, heating-cooling and fresh water are the useful outputs produced by the combined plant. For this purpose, the Brayton cycle, organic Rankine cycle, multi-effect distillation plant, single-effect absorption cooling plant, hydrogen generation and liquefaction unit are used in the multigeneration system design. The study targets are to design a novel multigeneration system design, develop the related software codes, analyze the system thermodynamically, and evaluate the effects of plant design indicators. Thermodynamic assessment results indicate that the energy efficiency of the multigeneration system ranges between 63.64% and 74.31%, the exergy efficiency value ranges from 55.67% to 67.35%. Parametric analyses performed in this study indicate that the most influential parameter is the fuel mass flow rate. Also, it should be stated that an increase in the dead state temperature, combustion chamber temperature, and fuel mass flow rate positively affects the plant effectiveness.

A comprehensive evaluation of a novel integrated system consisting of hydrogen boil-off gas reliquifying process and polymer exchange membrane fuel cell using exergoeconomic and Markov analyses

The price of constructing hydrogen generation units is very high and sometimes it is not possible to build them in the desired location, so the transfer of hydrogen from the hydrogen generation system to the units that need it is justified. Since the storage of hydrogen gas needs a large volume and its transportation is very complex, so if hydrogen is stored in liquid form, this problem can be resolved. In transporting liquid hydrogen (LH2) over long distances, owing to heat transfer to the environment, the LH2 vaporizes, forming boil-off gas (BOG). Herein, in lieu of only reliquifying the BOG, this study proposes and assesses a system employing the BOG partially as feed for a novel liquefaction process, and also the remaining utilized in a proton exchange membrane fuel cell (PEMFC) to generate power. Using the cold energy of the onsite liquid oxygen utility of the LH2 cargo vessel, the mixed refrigerant liquefaction cycle is further cooled down. In this regard, by using 130 kg/h BOG as input, 60.37 kg/h of liquid hydrogen is produced and the rest enters PEMFC with 552.7 kg/h oxygen to produce 1592 kW of power. The total thermal efficiency of the integrated system and electrical efficiency of the PEMFC is 83.18% and 68.76%, respectively. Regarding the liquefaction cycle, its specific power consumption (SPC) and coefficient of performance (COP) were achieved at 3.203 kWh/kgLH 2 and 0.1876, respectively. The results of exergy analysis show that the exergy destruction of the whole system is 937.4 kW and also its exergy efficiency is calculated to be 58.38%. Exergoeconomic and Markov analyses have also been applied to the integrated system. Also, by changing the important parameters of PEMFC, its optimal performance has been extracted.

Development and CFD analysis for determining the optimal operating conditions of 250 kg/day hydrogen generation for an on-site hydrogen refueling station (HRS) using steam methane reforming

The objective of this study to develop and undertake a comprehensive CFD analysis of an effective state-of-the-art 250 kg/day hydrogen generation unit for an on-site hydrogen refueling station (HRS), an essential part of the infrastructure required for fuel cell vehicles and various aspects of hydrogen mobility. This design consists of twelve reforming tubes and one newly designed metal fiber burner to ensure superior emission standards and performance. Experimental and computational modeling steps are conducted to investigate the effects of various operating conditions, the excess air ratio (EAR) at the burner, the gas hourly space velocity (GHSV), the process gas inlet temperature, and the operating pressure on the hydrogen production rate and thermal efficiency. The results indicate that the performance of the steam methane reforming reactor increased significantly by improving the combustion characteristics and preventing local peak temperatures along the reforming tube. It is shown that EAR should be chosen appropriately to maximize the hydrogen production rate and lifetime operation of the reformer tube. It is found that high inlet process gas temperatures and low operating pressure are beneficial, but these parameters have to be chosen carefully to ensure proper efficiency. Also, a high GHSV shortens the residence time and provides unfavorable heat transfer in the bed, leading to decreased conversion efficiency. Thus, a moderate GHSV should be used. It is shown that heat transfer is an essential factor for obtaining increased hydrogen production. This study addresses the pressing need for the HRS to adopt such a compact system, whose processes can ensure greater hydrogen production rates as well as better durability, reliability, and convenience.

Design and analysis of nuclear and solar-based energy, food, fuel, and water production system for an indigenous community

For the sustainable communities, there is a strong need to address the United Nations' sustainable development goals for communities, cities and countries. In this paper, we develop a unique hybrid energy system for cleaner productions of energy, fuel, food and water for an indigenous community by addressing the following goals, namely: zero hunger; clean water; affordable and clean energy; industry, innovation and infrastructure; sustainable cities and communities; and climate action. Also, the present sustainable system is investigated thermodynamically by considering energy and exergy criteria and evaluated through energy and exergy efficiencies. As a case study, the Saugeen First Nation indigenous community in the Bruce Peninsula in Ontario, Canada, is selected for meeting the demands of useful commodities where an integration of a newly developed multigenerational system with an existing nuclear reactor is achieved in order to provide food security, supply the freshwater for drinking purposes, and meet the community's electricity and heat demands. Moreover, to exploit the existing thermophysical properties of fluids in the nuclear system, a hydrogen generation unit is proposed. The novel integration is enhanced the current nuclear system and increased the variety of useful outputs. The overall system is analyzed according to the first and second laws of thermodynamics. A transient (time-dependent) analysis is carried out via hourly simulations with software packages and hourly sensitive meteorological data. The overall system performance results are obtained as 65.8% for energy efficiency and 40.1% exergy efficiency at average ambient conditions for a 126.04 mol/s hydrogen production rate.

Energy and economic analysis of a hydrogen and ammonia co-generation system based on double chemical looping

In this work, a model of hydrogen production by double chemical looping is introduced. The efficiency benefit obtained was investigated. The chemical looping hydrogen generation unit is connected in series to the downstream of a chemical looping gasification unit as an additional system for 100 MW·h coal gasification, with the function of supplementary combustion to produce hydrogen. Using Aspen Plus software for process simulation, the production of H2 and N2 in the series system is higher than that in the independent Chemical looping gasification and Chemical looping hydrogen generation systems, and the production of hydrogen is approximately 25.63% and 12.90% higher, respectively; The study found that when the gasification temperature is 900 °C, steam-carbon ratio is 0.84 and oxygen-carbon ratio is 1.5, the hydrogen production rate of the system was the maximum. At the same time, through heat exchange between logistics, high-pressure steam at 8.010 × 104 kg·h−1 and medium-pressure steam at 1.101 × 104 kg·h−1 are generated, and utility consumption is reduced by 61.58%, with utility costs decreasing by 48.69%. An economic estimation study found that the production cost of ammonia is 108.66 USD·(t NH3)−1. Finally, cost of equipment is the main factors influencing ammonia production cost were proposed by sensitivity analysis.

Risk assessment of hydrogen generation unit considering dependencies using integrated DEMATEL and TOPSIS approach

Hydrogen generation is with highly operational risk, and the catastrophic consequence may be caused as hydrogen is easily inflammable and explosive. It is of great importance to perform an effective risk assessment to ensure the operational safety of hydrogen generation unit. This paper presents a novel framework comprising of fuzzy DEMATEL implemented with TOPSIS to assess the comprehensive risk of hydrogen generation unit. This methodology is capable of capturing the interdependencies among different hazards, and prioritize the hazards in the decision-making process. An index-based risk assessment system is built by identifying hazards related to hydrogen generation. Subsequently, fuzzy DEMATEL is used to extract the interrelationships among risk indices and determine their weights, and TOPSIS model is utilized to prioritize hazards and calculate their risk values. Eventually, the risk of hydrogen generation unit is assessed by integrating the initial risk values with the weights of evaluation indices. The safety strategies based on assessment outcomes are developed to reduce the risk of hydrogen generation. A case study is used to test the practicability of the methodology, and it is observed that it can be a useful tool to risk assessment and management of hydrogen generation unit.