Hydrogen Production System Research Articles

Integration of biomass gasification and O2/H2 separation membranes for H2 production/separation with inherent CO2 capture: Techno-economic evaluation and artificial neural network based multi-objective optimization

This study delves into the thermodynamic and techno-economic intricacies of a cutting-edge hydrogen production system driven by biomass gasification. The quest for zero emissions propels our innovative integration of an oxygen transport membrane and a hydrogen separation membrane, strategically optimized through artificial intelligence. By situating the oxygen transport membrane near the gasifier, efficient heat transfer and oxygen production synergistically enhance the molar fraction of hydrogen in the syngas. Subsequent utilization of the hydrogen separation membrane, coupled with water gas shift reactors, not only facilitates hydrogen separation and purification but also achieves inherent carbon dioxide capture and storage. This novel membrane-based approach obviates the need for a conventional carbon capture system. Before optimization, our system exhibited a generation rate of approximately 10.29 tons of H2 per day. The levelized cost of production stands at $2.78 per kilogram of hydrogen, with power consumption estimated at 2.99 kWh/kg-H2. The calculated payback period is 9.96 years, considering a sales cost of $3.50 per kg-H2. Multi objective optimization reveals promising prospects, with a potential 26% reduction in power consumption in one scenario. An alternative scenario indicates a remarkable 20% decrease in the system's payback period, accompanied by an 8% dip in the levelized cost of H2. These findings underscore the economic and energy benefits of our membrane-integrated hydrogen production system.

Distributionally robust planning method for expressway hydrogen refueling station powered by a wind-PV system

Hydrogen fuel has received widespread attention as one of the critical solutions to global energy issues. The popularization of hydrogen fuel cell vehicles (HFCV) requires the deep integration of transportation and energy fields. Considering the complementarity of wind and PV power in remote areas, this paper proposes a planning model of an expressway hydrogen refueling station, including a hydrogen production system (HPS) powered by a wind-PV system and several hydrogen refueling systems (HRSs). The interaction and operation constraints of hydrogen production, storage, delivery, and demand are employed to complete hydrogen supply chain integration in the deterministic planning model. The spatiotemporal distribution of refueling demand at each HRS is obtained by Monte Carlo Simulation. Furthermore, we consider the impact of uncertainty related to renewable energy generation and refueling demand on planning and depict them by ambiguity sets based on Kullback Leibler divergence. The planning problem is transformed into a data-driven distributionally robust model and solved by Value-at-Risk and sample average approximation method. Results indicate that 1) The proposed model can simultaneously collaborate with the segments of the hydrogen supply chain. 2) The proposed method balances the planning reliability and economic efficiency and enhances solution robustness.

Towards sustainable energy Carriers: A solar and Wind-Based systems for green liquid hydrogen and ammonia production

Power-to-fuel energy systems have an essential need for decarbonizing energy carriers. This study proposes a solar and wind energy-based system for producing liquid hydrogen and ammonia as energy carriers. The proposed system caters to urban requirements encompassing electricity, cooling, heating, and freshwater. Three different scenarios, only liquid hydrogen, only ammonia, and dual production, are considered and compared. An artificial neural network is employed for prediction and computational time reduction, coupled with a genetic algorithm for system optimization. For a case in which 40 % of the net power is used in the electrolyzer, and the system simultaneously produces liquid hydrogen and ammonia, the overall energy and exergy performance of the system are 56.78 % and 44.69 %, respectively. In this case, the system has the capability of producing 13.2 MW of net power, 0.057 kg/s of liquid hydrogen, 0.162 kg/s of cold ammonia, 3.63 kg/s of freshwater, and 3.4 MW cooling load. The exergy analysis of the system reveals that the Rankine cycle and the electrolyzer have the highest exergy destruction, at 27 % and 21 %, respectively. Using the Technique for Order Preference by Similarity to Ideal Solution method, the optimal liquid hydrogen rate, ammonia production rate, overall exergy efficiency, and net power are determined as 0.026 kg/s, 0.151 kg/s, 51.38 %, and 16.52 MW respectively are recognized as optimal values for dual production scenario.

Methanol compared to other fuels for on-board hydrogen production in thermally balanced membrane reactors with internal recycle

New processes for hydrogen production from various sources are required, which will enable decentralized hydrogen utilization. Hydrogen is a challenging energy carrier due to its low volumetric energy density, requiring compression or liquefaction, which are costly steps, reducing the overall energy transformation cycle efficiency. Thus, a hydrogen supply route based on distributed on-demand production is more attractive compared to the traditional centralized production route. In this work we analyze the use of methanol as a hydrogen carrier to be converted to hydrogen in a conceptual autothermal scaled-down system for on-board pure hydrogen production. This system integrates two concentric reactors, membrane separation and heat exchange. The required heat is supplied by catalytic combustion of the reforming effluents which are recycled internally. The temperature profile is controlled by distribution of the combustion feed. A validated mathematical model shows that the thermal efficiency of the hydrogen production process from methanol will be much higher (e.g. 45 % vs 15 % in one case, 60 % vs 30 % in another case) compared to the efficiency obtained when feeding other fuels (methane, ethanol or glycerol). In all cases full conversion of the fuel is obtained. The reason for such a significant intensification is the lack of methane formation in the reforming reactor. This leads to higher driving force for hydrogen transport through the membranes and enables lower operating temperatures, reducing heat losses to the surroundings (which are the main source for efficiency loss). The lack of methane formation is due to the Cu-based catalyst used for methanol reforming, as opposed to the Ni-based catalyst used for reforming of other fuels.

Real-time optimization of large-scale hydrogen production systems using off-grid renewable energy: Scheduling strategy based on deep reinforcement learning

Aiming to amplify the renewable energy consumption capacity, this study delineates the development of an off-grid Renewable Energy Large-Scale Hydrogen Production System (H2-RES). The system was optimized for economic efficiency and safety, promising a reduction in both the investment cost for grid connection and the overall cost of hydrogen production from electrolytic water. We presented a comprehensive mathematical model for each H2-RES unit and designed a control strategy to enhance energy optimization and management. An intelligent energy scheduling policy empowered by the DDPG algorithm is introduced for optimal decision-making in continuous state and action spaces. Comparative analysis with traditional control policies, PSO, and DQN algorithms underscores the superior economic efficiency, enhanced renewable energy consumption, and safe operation facilitated by DDPG. These findings underscore the academic and engineering potential of DDPG in the energy dispatch of H2-RES.

A review of the integration of the copper-chlorine cycle with other systems for hydrogen production

There are different methods for hydrogen production, among which thermo-chemical cycles are particularly important. One of the most common thermochemical cycles is the copper-chlorine cycle. In this cycle, the water electrolysis process takes place during a thermo-chemical reaction, and copper chlorine is used as a thermochemical reaction intermediate. This cycle requires two factors to produce hydrogen: A heat source with a temperature of about 520 oC and electricity. For this reason, it is possible to use the hot waste gases of industries or parabolic through collector and heliostat field to provide its heat. To supply electricity for this cycle, various alternatives from the power grid and wind turbine to heat recovery in cycles that use low-temperature energy sources are considered. In this article, the integration of the copper-chlorine cycle with power generation systems has been discussed and investigated from the perspective of energy, exergy, and economics. This review is divided into two general parts using renewable and non-renewable resources. At the beginning of this article, various methods of hydrogen production focusing on the copper-chlorine cycle have been briefly discussed. In the following, the way this cycle works is explained along with energy, exergy, and economic equations, and the research done in this direction is explained. Finally, a strategy for how to integrate the copper-chlorine cycle with other systems is described. Studying this article, in addition to giving a better attitude in the field of integrating this cycle with other plants, is similar to a guideline for using the cycle along with other systems for better productivity. The conducted investigations showed that the recovery of hot industrial exhaust gas as a source of heat for the Cu-Cl cycle has a high potential for saving energy consumption and reducing environmental pollutants. To produce the required electricity, it is recommended to use cycles that work with a low-temperature energy source, such as the organic Rankine cycle and Kalina cycles. Also, if renewable energy sources are used, it is recommended to use parabolic through collectors and heliostats to produce the required heat. As in the case of non-renewable energy sources, cycles with low-temperature energy sources can be used.

Decoupled electrolysis for hydrogen production and hydrazine oxidation via high-capacity and stable pre-protonated vanadium hexacyanoferrate

Decoupled electrolysis for hydrogen production with the aid of a redox mediator enables two half-reactions operating at different rates, time, and spaces, which offers great flexibility in operation. Herein, a pre-protonated vanadium hexacyanoferrate (p-VHCF) redox mediator is synthesized. It offers a high reversible specific capacity up to 128 mAh g−1 and long cycling performance of 6000 cycles with capacity retention about 100% at a current density of 10 A g−1 due to the enhanced hydrogen bonding network. By using this mediator, a membrane-free water electrolytic cell is built to achieve decoupled hydrogen and oxygen production. More importantly, a decoupled electrolysis system for hydrogen production and hydrazine oxidation is constructed, which realizes not only separate hydrogen generation but electricity generation through the p-VHCF-N2H4 liquid battery. Therefore, this work enables the flexible energy conversion and storage with hydrogen production driven by solar cell at day-time and electricity output at night-time.

Comparative optimization study and 4E analysis of hybrid hydrogen production systems based on PEM, and VCl methods utilizing steel industry waste heat

Global warming and climate change are the challenges caused mainly by greenhouse gases. To tackle the issue, limiting the emission of these gases would be essential. This study conducted a technical and economic evaluation of hydrogen production from waste heat using a proton exchange membrane electrolyzer and a vanadium chloride thermochemical cycle. These systems are integrated separately and in combination with Rankine steam and organic cycles to form three different hybrid systems. These three systems operate at the same input energy through factory waste heat at 810 °C. Each system was separately optimized—employing a genetic algorithm and artificial neural network—to find the best performance points from economics, environment, energy, and exergy viewpoints. Then, the performance of the three systems is examined and compared. The results indicate that the vanadium chloride system outperforms the proton exchange membrane and proton exchange membrane-vanadium chloride in terms of hydrogen production and efficiency. vanadium chloride cycle, as the best scenario, showed the capacity to produce 203.018 tons of hydrogen annually along with 18,504 MWh of energy per year, with energy and exergy efficiencies of 43.71 % and 56.69 %, respectively. Economic analysis results indicate that the payback period for proton exchange membrane, vanadium chloride, and proton exchange membrane-vanadium chloride are 9.829, 4.228, and 6.383 years, respectively. Furthermore, the CO2 emissions reduction for the three scenarios proton exchange membrane, vanadium chloride, and proton exchange membrane-vanadium chloride is 8378, 11201, and 10,002 tons per year, respectively.

Substantiation by Calculation of a System for Hydrogen Production from Biomass Using Chemical Looping Gasification

Substantiation by Calculation of a System for Hydrogen Production from Biomass Using Chemical Looping Gasification

Perovskite-based Z-scheme photocatalytic system for hydrogen production

Photocatalytic hydrogen production is recognized as a promising approach to produce greener hydrogen. The development of next-generation photocatalytic materials aims to enhance photocatalysis efficiency. Perovskite, a third-generation photocatalytic material, has gained interest in photocatalytic water splitting due to its optical stability, structural flexibility, bandgap tunability, and charge transfer efficiency. However, the perovskites are not able to achieve the targeted efficiency. Perovskite-based Z-scheme heterojunction photocatalysts can enhance efficiency. This review gives special attention to types and the formation of Z-schemes. In particular, photocatalysts involved in all-solid-state and direct Z-scheme for photocatalytic hydrogen production have been discussed.

Energy, exergy analysis in a hybrid power and hydrogen production system using biomass and organic Rankine cycle

This study conducts a thorough analysis of an integrated system that has been specifically engineered to generate power and hydrogen concurrently by utilizing biomass and an Organic Rankine Cycle (ORC). Under its feed fluid heater and heat recovery exchanger, the ORC exhibits a dual-generation capability and is powered by biomass combustion. This research investigates a range of ORC configurations that utilize unique working fluids specifically designed for hydrogen production. A comprehensive thermodynamic model is applied to each fluid. An essential goal is to perform a parametric analysis, wherein the impact of critical parameters on the overall performance of the system is thoroughly examined. In addition, an innovative system comprising an integrated proton membrane exchange electrolyzer and biomass in ORC is presented in this study. An evaluation of the energy and exergy efficiencies of five distinct working fluids (R113, R114, R218, RC318, and R236fa) is conducted. The R113 working fluid exhibited the highest energy and exergy efficiencies, whereas the other fan working fluids were found to possess noteworthy characteristics. The R113 working fluid exhibits exergy and energy efficiencies of 67.15 % and 3.69 %, respectively. In addition, the study reveals valuable information regarding exergy losses in the electrolyzer and evaporator, emphasizing their impact on the generation of electricity. This study clarifies the correlation between fluctuations in temperature within the biomass fluid and the subsequent alterations in power and hydrogen generation, uncovering a compromise characterized by a reduction in energy and exergy efficiency. Furthermore, the research illustrates how escalating the mass flow rates of biomass fluids results in a decline in energy and exergy efficiency while concurrently generating power and hydrogen.

All-perovskite-based unassisted photoelectrochemical water splitting system for efficient, stable and scalable solar hydrogen production

All-perovskite-based unassisted photoelectrochemical water splitting system for efficient, stable and scalable solar hydrogen production

Parametric Study and Optimization of Hydrogen Production Systems Based on Solar/Wind Hybrid Renewable Energies: A Case Study in Kuqa, China

Based on the concept of sustainable development, to promote the development and application of renewable energy and enhance the capacity of renewable energy consumption, this paper studies the design and optimization of renewable energy hydrogen production systems. For this paper, six different scenarios for grid-connected and off-grid renewable energy hydrogen production systems were designed and analyzed economically and technically, and the optimal grid-connected and off-grid systems were selected. Subsequently, the optimal system solution was optimized by analyzing the impact of the load data and component capacity on the grid dependency of the grid-connected hydrogen production system and the excess power rate of the off-grid hydrogen production system. Based on the simulation results, the most matched load data and component capacity of different systems after optimization were determined. The grid-supplied power of the optimized grid-connected hydrogen production system decreased by 3347 kWh, and the excess power rate of the off-grid hydrogen production system decreased from 38.6% to 10.3%, resulting in a significant improvement in the technical and economic performance of the system.

Techno-economic analysis of green hydrogen production using a 100 MW photovoltaic power generation system for five cities in North and Northwest China

In recent years, photovoltaic power generation technology has developed rapidly, but due to its impact on the stability and security of the power grid, some areas in North and Northwest China have a certain degree of photovoltaic power curtailment phenomenon. Hydrogen is considered a good medium for energy storage, and the photovoltaic power generation system based on hydrogen energy storage has been the focus of research. Therefore, this work established simulation models of a photovoltaic power generation with a rated capacity of 100 MW coupling with hydrogen production system using MATLAB software and performs real-time simulation. Techno-economic performance of the integration system in five cities of Hami, Ordos, Datong, Yinchuan, and Yulin was analyzed. The results show that the coupling system can generate 158484–175675 MWh of electricity annually, which can drive the electrolyzer to produce 2524–2761 tonnes of hydrogen. The energy efficiency of the overall system and levelized cost of hydrogen are 9.03–9.31 % and 25.95/22.54–28.38/24.97 CNY/kg. The total CO2 emissions reduction and carbon credits earned by the established system over a lifetime of 20 years can reach 1.81–2.00 million tonnes and 92.19–102.19 million CNY. This paper will provide economic and energy efficiency reference for studying the coupling of green hydrogen production systems with the coal chemical industry in the above regions.

A new system for hydrogen and methane production with post-combustion amine-based carbon capturing option for better sustainability

In the present paper, a novel integrated multigeneration system is developed to produce hydrogen and methane simultaneously driven by a renewable energy source. Besides, this system captures carbon dioxide from a coal power plant through an amine-based absorber and stripper. Also, solar energy is set to provide the heat required for the system. The generated power is used for different purposes from the coupled Brayton-Rankine combined cycle. There are two methods of iron-based chemical looping with four reactors and steam methane reforming, which are integrated into the system to produce hydrogen and store it at the same time. After gaining enough heat and electricity from mixing and heating the CO2 and H2, the methane is then produced, stored or used for different purposes during the system. This system primarily utilizes solar energy to produce the required heat of the system which is suitable for sunny locations. The governing and balance equations are employed to determine the energy and exergy efficiencies, methane and hydrogen production rates and carbon capture percentage as 48 %, 32 %, 0.0048 kg/s and 0.004 kg/s and 80 % carbon capturing.

CO2-Free Hydrogen Production by Methane Pyrolysis Utilizing a Portion of the Produced Hydrogen for Combustion

Air pollutants such as carbon dioxide and nitrogen oxides emitted by the combustion of fossil fuels have become the subject of increasing concern. Hydrogen has accordingly emerged as a promising low-emission alternative energy source. Among the various methods for hydrogen production, methane pyrolysis, which produces hydrogen without emitting carbon dioxide, has gained substantial attention. This study evaluated the self-sustainability of a new hydrogen production system based on methane pyrolysis, in which a portion of the hydrogen produced is used as combustion fuel rather than relying on catalysts and electrical heating. Coupled heat transfer and one-dimensional reaction simulations employing two plug-flow reactors of a counterflow double-pipe heat exchanger were conducted to investigate the feasibility and efficiency of the proposed system, as well as the influence of flow conditions on hydrogen production. The results confirmed system viability, informed the estimation of hydrogen production rates, and provided methane conversion rate data emphasizing the critical role of low-flow conditions and residence time in system efficiency. Additionally, the production of carbon constituted a significant aspect of system efficiency. These findings indicate that the proposed system can produce environmentally friendly hydrogen, contributing to its potential utilization as a sustainable energy source.

An energy-economic analysis of a hybrid PV/wind/battery energy-driven hydrogen generation system in rural regions of Egypt

The production of storable green hydrogen via water electrolysis, driven by renewable energy, is an attractive alternative for paving the way for a carbon-free business and a feasible path to energy sustainability. This study investigated the technical and economic feasibility of a stand-alone hybrid renewable energy system (PV/WT-BS/WE) that relied on a photovoltaic (PV), wind turbine (WT), battery storage (BS) and water electrolyzer (WE) to generate electricity and green hydrogen in three Egyptian regions with different climate. The targeted outcomes in terms of electricity and hydrogen generation, system efficiency, and cost analysis are computed, displayed, and compared with other hydrogen production scenarios with various working policies includes (PV-BS/WE), (PV/WT-WE), and (PV-WE) utilizing MATLAB/Simulink computer simulation. According to the findings, the PV/WT-BS/WE scenario is more advantageous in Ras Ghareb as an optimal site, with a yearly generation of electricity, hydrogen of (16,984.64 kWh, 3127.65 m3), and overall system average efficiency of 14.41 %. A favorable LCOH of 2.22 $/kg found in Ras-Garb, in northeastern Egypt. This study could guide authorities in developing various national-scale hydrogen production systems since it outlines the techno-economic features of various scenarios across the country. Additionally, the effectiveness of the suggested system is evaluated against existing literature.

Numerical study on a novel solar-thermal-reaction system for clean hydrogen production of methanol-steam reforming

Renewable energy-driven hydrogen production methods offer a promising solution for mitigating energy crises. The present study introduces a new solar-driven hydrogen production system that within methanol steam reforming (MSR) process. The numerical analysis is carried out using a cylindrical Fresnel linear concentrator coupled with a solar thermal reactor (STR). A comprehensive kinetic model of the MSR reaction was constructed and combined with analytical methods based on Monte Carlo ray tracing methods and finite volume methods to analyze the multi-physical properties involved in the reaction process. The results indicate that a novel solar-driven MSR-STR system can generate a sufficient driving force after adjusting the concentrator structure and relative position to match the energy demand of the MSR reaction. The accuracy of the model is compared with the experimental values, and the average error is 7.8 %. Tracking error of the component should be maintained below 1.5° to ensure the optical efficiency. The annual hydrogen production was analyzed and the levelized cost of hydrogen is $1.77/kg. Finally, a comparison is presented between the proposed MSR-STR system and parabolic trough concentrator based MSR hydrogen production system to evaluate the feasibility of the former in terms of the economics of implementation.

Numerical study on novel parabolic trough solar receiver-reactors with double-channel structure catalyst particle packed beds by developing actual three-dimensional catalyst porosity distributions

Flow channel structure and operation strategy play important role in fixed packed bed based parabolic trough solar receiver-reactors (PTSRRs) for efficient hydrogen production. A horizontal separated double-channel structure with the countercurrent control strategy (H-DCS-CCS) and a vertical separated double-channel structure with the flow matching strategy (V-DCS-FMS) were proposed for better coupling of multiple physical fields in PTSRRs. A three-dimensional comprehensive numerical model was developed to simulate the complex optical-thermal-chemical process and real spatial pore structure characteristics of novel PTSRRs, based on a proposed coupling calculation procedure of actual three-dimensional catalyst porosity distributions. After validation, the effect mechanism of novel double-channel structures and operation strategies were further investigated. It was revealed that the H-DCS-CCS can significantly reduce the PTSRR maximum temperature, increasing the upper limit of the methanol conversion rate by 7.15%. The V-DCS-FMS can effectively improve the temperature uniformity and the reaction performance within tuned flow rate ratio ranges. This proposed novel concept could provide guidance for similar solar-driven thermochemical hydrogen production systems.

Performance Evaluation of High Current Density (HCD) Solid Oxide Electrolysis Cell (SOEC) Hydrogen Production System in Endothermic Mode: An Energy and Exergy Perspective

Performance Evaluation of High Current Density (HCD) Solid Oxide Electrolysis Cell (SOEC) Hydrogen Production System in Endothermic Mode: An Energy and Exergy Perspective