Water electrolysis based on renewable energy for hydrogen production

As an energy storage medium,hydrogen has drawn the attention of research institutions and industry over the past decade,motivated in part by developments in renewable energy,which have led to unused surplus wind and photovoltaic power.Hydrogen production from water electrolysis is a good option to make full use of the surplus renewable energy.Among various technologies for producing hydrogen,water electrolysis using electricity from renewable power sources shows greatpromise.To investigate the prospects of water electrolysis for hydrogen production,this review compares different water electrolysis processes,i.e.,alkaline water electrolysis,proton exchange membrane water electrolysis,solid oxide water electrolysis,and alkaline anion exchange membrane water electrolysis.The ion transfer mechanisms,operating characteristics,energy consumption,and industrial products of different water electrolysis apparatus are introduced in this review.Prospects for new water electrolysis technologies are discussed.

Review of renewable energy-based hydrogen production processes for sustainable energy innovation

In this review,we primarily analyze the hydrogen production technologies based on water and biomass,including the economic,technological,and environmental impacts of different types of hydrogen production technologies based on these materials,and comprehensively compare them.Our analyses indicate that all renewable energy-based approaches for hydrogen production are more environmentally friendly than fossil-based hydrogen generation approaches.However,the technical ease and economic efficiency of hydrogen production from renewable sources of energy needs to be further improved in order to be applied on a large scale.Compared with other renewable energy-based methods,hydrogen production via biomass electrolysis has several advantages,including the ease of directly using raw biomass.Furthermore,its environmental impact is smaller than other approaches.Moreover,using a noble metal,catalyst-free anode for this approach can ensure a considerably low power consumption,which makes it a promising candidate for clean and efficient hydrogen production in the future.

Energy Scenario: Production, Consumption and Prospect of Renewable Energy in Australia

Australia is the world’s 9th largest energy producer, 17th largest consumer of non-renewable energy resources and ranks 18th on a per person energy consumption basis.Australia’s energy consumption is primarily composed of non-renewable energy resources (coal, oil, gas and related products), which represent 96% of total energy consumption. Renewables, the majority of which is bioenergy (wood and wood waste, biomass, and biogas) combined with clear energy namely wind, solar hot water, solar electricity, hydroelectricity account for the remaining 4% consumption.Australia’s renewable energy resources are largely undeveloped which will contribute directly to the Australian economy. In this article, a review of literature on energy scenario is presented and discussed.Australia’s total energy production, consumption, storage and export (including renewable and non-renewable) data has been analyzed and discussed in this study. The main objective of the study is to analyze the prospect of renewable energy inAustralia. This study concludes that Australian economy will grow faster if its undeveloped renewable energies can be used efficiently for electricity generation and transport sector.

Renewable Methanol Production Using Captured Carbon Dioxide and Hydrogen Generated through Water-Splitting

The global warming issues associated with fossil fuels have forced the world to shift towards environment-friendly alternatives. The studies on the capture and storage of CO2 have gained significant research attention, and to attract the world towards CO2 capturing and storing, it is necessary to find suitable applications for this captured CO2. Methanol is one of the products which can be produced by utilizing the captured CO2 and hydrogen that can be produced by water splitting. Keeping in view both these green fuel production processes, this study proposes a combined application of both these technologies for the production of methanol, which is an important chemical used in manufacturing industries. This review paper presents a brief study of both carbon capture and hydrogen production technologies. It also provides research trends, economic aspects, and methods of incorporating both these technologies to produce methanol. Additionally, the prospects of the approach in Oman have also been presented.

Economic analysis of hydrogen production from electrolyzed water technology by provinces in China

A novel model for measuring the economics of hydrogen generation via electrolytic water projects was constructed.The model overcomes the current problem of incomplete and inaccurate assessments of the price of producing hydrogen via water,which are caused by ignoring the indirect carbon costs of different power generation sources in the process of determining the cost of producing hydrogen via water.The model was used to analyze the price of producing hydrogen via water electrolysis and its sensitivity to the electricity costs of hydrogen production and carbon prices in various provinces of China.With the continuing increase in the penetration of novel energy in China’s power system and the gradual decline in electricity prices,the price of producing hydrogen via electrolytic water is expected to be close to or even lower than that of producing hydrogen via coal in the future.Geographical differences also have a significant impact on the price of producing hydrogen,which is typically higher in the southeastern coastal region than in the western region,because of the local price of electricity and the composition of the energy sources.Provinces that have been effective in developing novel energy sources,such as Qinghai,Sichuan,and others,have been effective in the hydrogen energy industry.Sichuan and other provinces with significant new energy development have a clear advantage in the hydrogen industry.Because provinces with low hydrogen production costs can transport hydrogen to provinces with high hydrogen production costs through pipelines,hydrogen pipelines are planned from Shaanxi to Henan and from Xinjiang to Nei Mongol.These study results reveal the relative economic advantages of producing hydrogen via water electrolysis under various energy and electricity price policies and provide new perspectives on China’s energy strategy and the growth of the hydrogen energy sector.

Hydroelectric and Hydrogen Storage Systems for Electric Energy Produced from Renewable Energy Sources

Renewable energy sources are essential formitigating the greenhouse effect and supplying energy to resource-scarce regions.However,their intermittent nature necessitates efficient storage solutions to enhance system efficiency and manage energy costs.This paper investigates renewable and clean storage systems,specifically examining the storage of electricity generated from renewable sources using hydropower plants and hydrogen,both of which are highly efficient and promising for future energy production and storage.The study utilizes extensive literature data to analyze the impact of various parameters on the cost per kWh of electricity production in hybrid renewable systems incorporating hydropower and hydrogen storage plants.Results indicate that these hybrid systems can store electricity efficiently and cost-effectively,with production costs ranging from 0.126 to 0.3$/kWh for renewablehydropower systems and 0.118 to 0.42$/kWh for renewable-hydrogen systems,with expected cost reductions over the next decade due to technological advancements and increased market adoption.The novelty of this study lies in its comprehensive comparison of hybrid renewable systems integrating hydropower and hydrogen storage,providing detailed cost analysis and future projections.It identifies key parameters influencing the cost and efficiency of these systems,offering insights into optimizing storage solutions for renewable energy.Moreover,this research underscores the potential of hybrid systems to reduce dependency on fossil fuels,particularly during peak demand periods,and emphasizes the importance of seasonal and geographic considerations in selecting energy sources.The study highlights the importance of policy support and investment in hybrid renewable systems and calls for further research into optimizing these systems for different seasonal and geographic conditions.Overall,the integration of renewable energy sources with hydropower and hydrogen storage offers a promising pathway to a sustainable,economical,and resilient energy future.

Progress in manipulating spin polarization for solar hydrogen production

Photocatalytic and photoelectrochemical water splitting using semiconductor materials are effective approaches for converting solar energy into hydrogen fuel.In the past few years,a series of photocatalysts/photoelectrocatalysts have been developed and optimized to achieve efficient solar hydrogen production.Among various optimization strategies,the regulation of spin polarization can tailor the intrinsic optoelectronic properties for retarding charge recombination and enhancing surface reactions,thus improving the solar-to-hydrogen(STH)efficiency.This review presents recent advances in the regulation of spin polarization to enhance spin polarized-dependent solar hydrogen evolution activity.Specifically,spin polarization manipulation strategies of several typical photocatalysts/photoelectrocatalysts(e.g.,metallic oxides,metallic sulfides,non-metallic semiconductors,ferroelectric materials,and chiral molecules)are described.In the end,the critical challenges and perspectives of spin polarization regulation towards future solar energy conversion are briefly provided.

Ethanol steam reforming study over ZSM-5 supported cobalt versus nickel catalyst for renewable hydrogen generation

The renewable hydrogen generation through ethanol steam reforming is one of the anticipated areas for sustainable hydrogen generation. To elucidate the role of Ni and Co with ZSM-5 support, catalysts were prepared by wet impregnation method and ethanol steam reforming(ESR) was performed. The catalysts were characterized by HR-XRD, ATR–FTIR, HR-SEM, TEM with SAED, EDAX, surface area analyzer and TPR. It had shown complete ethanol conversion at 773 K, but the selectivity in hydrogen generation was found higher for 10% Ni/ZSM-5 catalyst as compared to 10% Co/ZSM-5. The 10% Ni/ZSM-5 catalyst has about 72% hydrogen selectivity at temperature 873 K. It indicates that Ni is a more sustainable catalyst as compared to Co with ZSM-5 support for ESR. The C_2H_4 was found major undesirable products up to 823 K temperature. Nevertheless, the 10% Ni/ZSM-5 catalyst had shown its stability for high temperature(873 K) ESR performance.

Latest progress in hydrogen production from solar water splitting via photocatalysis,photoelectrochemical,and photovoltaic-photoelectrochemical solutions

Hydrogen production via solar water splitting is regarded as one of the most promising ways to utilize solar energy and has attracted more and more attention. Great progress has been made on photocatalytic water splitting for hydrogen production in the past few years. This review summarizesthe very recent progress (mainly in the last 2–3 years) on three major types of solar hydrogenproduction systems: particulate photocatalysis (PC) systems, photoelectrochemical (PEC) systems,and photovoltaic‐photoelectrochemical (PV‐PEC) hybrid systems. The solar‐to‐hydrogen (STH)conversion efficiency of PC systems has recently exceeded 1.0% using a SrTiO3:La,Rh/Au/BiVO4:Mophotocatalyst, 2.5% for PEC water splitting on a tantalum nitride photoanode, and reached 22.4%for PV‐PEC water splitting using a multi‐junction GaInP/GaAs/Ge cell and Ni electrode hybrid system.The advantages and disadvantages of these systems for hydrogen production via solar watersplitting, especially for their potential demonstration and application in the future, are briefly describedand discussed. Finally, the challenges and opportunities for solar water splitting solutions are also forecasted.

Progress and Prospects of Hydrogen Production: Opportunities and Challenges

This study presents an overview of the current status of hydrogen production in relation to the global requirement for energy and resources.Subsequently,it symmetrically outlines the advantages and disadvantages of various production routes including fossil fuel/biomass conversion,water electrolysis,microbial fermentation,and photocatalysis(PC),in terms of their technologies,economy,energy consumption,and costs.Considering the characteristics of hydrogen energy and the current infrastructure issues,it highlights that onsite production is indispensable and convenient for some special occasions.Finally,it briefly summarizes the current industrialization situation and presents future development and research directions,such as theoretical research strengthening,renewable raw material development,process coupling,and sustainable energy use.

Oxidative reforming of methane for hydrogen and synthesis gas production:Thermodynamic equilibrium analysis

A thermodynamic analysis of methane oxidative reforming was carried out by Gibbs energy minimization （at constant pressure and temperature） and entropy maximization （at constant pressure and enthalpy） methods,to determine the equilibrium compositions and equilibrium temperatures,respectively.Both cases were treated as optimization problems （non-linear programming formulation）.The GAMS 23.1 software and the CONOPT2 solver were used in the resolution of the proposed problems.The hydrogen and syngas production were favored at high temperatures and low pressures,and thus the oxygen to methane molar ratio （O 2 /CH 4） was the dominant factor to control the composition of the product formed.For O 2 /CH 4 molar ratios higher than 0.5,the oxidative reforming of methane presented autothermal behavior in the case of either utilizing O 2 or air as oxidant agent,but oxidation reaction with air possessed the advantage of avoiding peak temperatures in the system,due to change in the heat capacity of the system caused by the addition of nitrogen.The calculated results were compared with previously published experimental and simulated data with a good agreement between them.

Renewable Energies, Present & Future

Fossil fuels are major cause of environmental destruction in pollutions. It has created much needed momentum for renewable energies, which are environmentally benign, generated locally, and can play a significant role in developing economy. As a sustainable energy sources, it can grow at a rapid pace to meet increasing demands for electricity in a cost-effective way.

Copper‐doped zinc sulfide nanoframes with three‐dimensional photocatalytic surfaces for enhanced solar driven H_(2) production

Solar‐to‐chemical energy conversion is perceived as one of the most potential solutions to the current energy and environmental crisis,yet requires major scientific endeavors on the development of efficient and sustainable photocatalysts.Remolding the composition and morphology of a semiconductor jointly for the purpose of improving photocatalysis efficiency remains challenging.Herein,we rationally fabricated Cu‐doped ZnS nanoframes via a simple conjunct strategy of substitutional doping,chemical acidic etching,and sulfidation,aiming at enhancing the light utilization and charge separation/transfer efficiency for solar‐light‐driven hydrogen generation.Cu‐doped zeolitic imidazolate framework‐8(ZIF‐8)rhombic dodecahedrons are transformed to hollow Cu‐ZIF‐8 nanoframes converted to Cu‐ZnS nanoframes with three‐dimensional photocatalytic active surfaces via anisotropic chemical etching,which is further converted to Cu‐ZnS nanoframes.By combining the merits of optimal heteroatom doping and frame‐like open architecture,the obtained 1%Cu‐doped ZnS nanoframe exhibits high photocatalytic activity under solar light irradiation with improved hydrogen production rate up to 8.30 mmol h^(–1) g^(–1) and excellent stability in the absence of cocatalysts,which is significantly improved in comparison with those of the bare ZnS and Cu‐ZnS with different morphologies.This work inspired by merging the merits of metal doping and anisotropic chemical etching may shed light on the rational design and fabrication of advanced photocatalysts.

The Prospects for Renewable Energy through Hydrogen Energy Systems

The prospects for renewable energy are enhanced through the use of hydrogen energy systems in which hydrogen is an energy carrier. As easily accessible fossil fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier. As the world’s energy sources become less fossil fuel-based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services, in a hydrogen economy. Thus, hydrogen energy systems allow greater use of renewable energy resources. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems, and their economics, are described and reviewed.

Modeling of Hydrogen Production in an Alkaline Electrolyser System Connected with a Solar Photovoltaic Panel or a Wind Turbine: Case Study;Douala-Cameroon

This article is in the field of research into the storage of renewable energy production. One of the main obstacles to the rapid development of renewable energies is the storage of the energy produced at low cost and with good efficiency. The production of hydrogen from renewable energies is a promising solution. The present work evaluates the potential of hydrogen production by electrolysis from solar photovoltaic and wind renewable energies in the city of Douala in Cameroon. The methodological approach used is based on the semi-empirical modelling approach of an alkaline electrolyser associated with the solar panel or the wind turbine. The simulation results obtained on the MATLAB/Simulink platform show that the average hydrogen production potential is estimated at 0.55 Nm3/h for a PV panel supply, which corresponds to average energy efficiency of 70%, and at 0.675 Nm3/h for a wind turbine supply, which corresponds to average energy efficiency of 84%. These results show the need to promote this technology, whose efficiency can be improved depending on the choice of site.

Fuzzy logic controller implementation on a microbial electrolysis cell for biohydrogen production and storage

This work presents the implementation of fuzzy logic control(FLC) on a microbial electrolysis cell(MEC).Hydrogen has been touted as a potential alternative source of energy to the depleting fossil fuels. MEC is one of the most extensively studied method of hydrogen production. The utilization of biowaste as its substrate by MEC promotes the waste to energy initiative. The hydrogen production within the MEC system, which involves microbial interaction contributes to the system's nonlinearity. Taking into account of the high complexity of MEC system, a precise process control system is required to ensure a wellcontrolled biohydrogen production flow rate and storage application inside a tank. Proportionalderivative-integral(PID) controller has been one of the pioneer control loop mechanism. However, it lacks the capability to adapt properly in the presence of disturbance. An advanced process control mechanism such as the FLC has proven to be a better solution to be implemented on a nonlinear system due to its similarity in human-natured thinking. The performance of the FLC has been evaluated based on its implementation on the MEC system through various control schemes progressively. Similar evaluations include the performance of Proportional-Integral(PI) and PID controller for comparison purposes. The tracking capability of FLC is also accessed against another advanced controller that is the model predictive controller(MPC). One of the key findings in this work is that the FLC resulted in a desirable hydrogen output via MEC over the PI and PID controller in terms of shorter settling time and lesser overshoot.

Tri-profit electrolysis for energy-efficient production of benzoic acid and H_(2)

Electrosynthesis has recently attracted intensive research attentions and holds great potential in implementing scalable green synthesis thanks to more and more readily accessible renewable electric energy.

Hydrogen production at intermediate temperatures with proton conducting ceramic cells:Electrocatalytic activity,durability and energy efficiency

Proton conducting ceramic cells(PCCs)are an attractive emerging technology operating in the intermediate temperature range of 500 to 700℃.In this work,we evaluate the production of hydrogen at intermediate temperatures by proton conducting ceramic cell electrolysis(PCCEL).We demonstrate a highperformance steam electrolysis owing to a composite positrode based on BaGd_(0.8)La_(0.2)Co_(2)O_(6-δ)(BGLC1082)and BaZr0.5Ce0.4Y0.1O3-δ(BZCY541).The high reliability of PCCEL is demonstrated for 1680 h at a current density as high as-0.8 A cm^(-2)close to the thermoneutral cell voltage at 600℃.The electrolysis cell showed a specific energy consumption ranging from 54 to 66 kW h kg^(-1)that is comparable to state-of-the-art low temperature electrolysis technologies,while showing hydrogen production rates systematically higher than commercial solid oxide ceramic cells(SOCs).Compared to SOCs,the results verified the higher performances of PCCs at the relevant operating temperatures,due to the lower activation energy for proton transfer comparing with oxygen ion conduction.However,because of the p-type electronic conduction in protonic ceramics,the energy conversion rate of PCCs is relatively lower in steam electrolysis.The faradaic efficiency of the PCC in electrolysis mode can be increased at lower operating temperatures and in endothermic conditions,making PCCEL a technology of choice to valorize high temperature waste heat from industrial processes into hydrogen.To increase the faradaic efficiency by optimizing the materials,the cell design,or the operating strategy is a key challenge to address for future developments of PCCEL in order to achieve even more superior techno-economic merits.

Design and optimization of electrochemical cell potential for hydrogen gas production

This study deals with the optimization of best working conditions in molten melt for the production of hydrogen(H2) gas.Limited research has been carried out on how electrochemical process occurs through steam splitting via molten hydroxide.54 combinations of cathode,anode,temperature and voltage have been investigated for the optimization of best working conditions with molten hydroxide for hydrogen gas production.All these electrochemical investigations were carried out at 225 to 300℃ temperature and 1.5 to 2.5 V applied voltage values.The current efficiency of 90.5,80.0 and 68.6% has been achieved using stainless steel anodic cell with nickel,stainless steel and platinum working cathode respectively.For nickel cathode,an increase in the current directly affected the hydrogen gas flow rate at cathode.It can be hypothesized from the noted results that increase in current is directly proportional to operating temperature and applied voltage.Higher values were noted when the applied voltages increased from 1.5 to 2.5 V at 300℃,the flow rate of hydrogen gas increased from 1.5 to 11.3 cm^(3) min^(-1),1.0 to 13 cm^(3) min^(-1) in case of electrolysis@stainless steel and@graphite anode respectively.It is observed that the current efficiency of stainless steel anodic cell was higher than the graphite anodic cell.Therefore,steam splitting with the help of molten salts has shown an encouraging alternate to current methodology for H2 fuel production.

Low Temperature H_(2) Production from Formic Acid Aqueous Solution Catalyzed on Metal Doped Mo_(2)C

Hydrogen is recognized as a promising energy scours in the close future.Online hydrogen preparation from formic acid under mild reaction conditions causes extensive interests.Mo_(2)C and metal(Fe,Ni,Co,K)doped Mo_(2)C on granular activated carbon(GAC)were prepared and used as heterogeneous catalysts for H2 generation from formic acid on a fixed bed reactor at 100–250°C.The formic acid conversions on doped Mo_(2)C-Me/GAC are clearly improved,especially at lower reaction temperatures.Co doping presents outstanding effect on H2 selectivity and conversion rate compared to Ni and Fe.A 56.3%formic acid conversion was reached on Mo_(2)C-Co/GAC at 100°C,which triples that on Mo_(2)C/GAC at the same temperature.At 150°C,a high formic acid conversion over 90%was reached on Mo_(2)C-Co/GAC.These long lifetime catalysts with no precious metal provide a low cost route to hydrogen production from formic acid.