Hydrogen Production Potential Research Articles

Exploring the Potential of Renewable Energy to Enable Green Hydrogen Production for a Sustainable Future

Abstract – Amidst intensifying concerns about greenhouse gas emissions, the imperative to transition towards sustainable energy solutions is paramount. Renewable energy sources (RES) provide a promising avenue, especially in hydrogen production. In this context, the emergence of “green hydrogen” is pivotal. Green hydrogen is a concept produced using RES like solar and wind energy to power the hydrogen production process. Unlike conventional methods emitting carbon dioxide, green hydrogen is generated through water electrolysis using clean energy. India relies on coal for around 70% of its energy needs, leading to a 29% rise in carbon emissions from 2015 to 2022. Green hydrogen is a potential alternative solution to address the increasing energy demand and the depletion of fossil fuels. Using wind energy for water electrolysis emerges as a suitable method for green hydrogen production. Therefore, in the present study, assessed the potential of hydrogen production using the wind energy resources in five selected locations in India using ERA5 hourly wind data. The investigation further explored the characteristics of wind speeds at these locations using average wind speed, Weibull parameters and wind rose analysis. Using the SUZLON S95 wind turbine, power output and annual energy generation at each location were estimated. Further, estimated the annual hydrogen production and required storage capacity at each location. The results showed a power generation of 891 kW in location Una and 895 kW in Mandvi. Finally, the amount of carbon emissions mitigated due to the use of wind energy sources instead of conventional sources for H2 production is calculated.

Utilization of Magnesium Chloride (Mg-Cl) cycle for Hydrogen Production of SOMBRERO Fusion Reactor

The aim of this study is to investigate the hydrogen production potential of the Mg-Cl (magnesium chloride) cycle in the SOMBRERO fusion reactor. Three different percentages of UO2 nuclear fuel, namely 2%, 6% and 10%, have been used while keeping the fuel zone thickness constant. The performance of the SOMBRERO fusion reactor has been considered statically. The neutronic calculations have performed with Monte Carlo neutron transport code. Firstly, it has been determined that the tritium breeding ratio (TBR) and energy multiplication factor (M) values depends on neutronically. Secondly, the amount of hydrogen production with by using energy multiplication factor (M) have been performed. The highest hydrogen production has been obtained as 8,12687 kg/s for 10% UO2 fuel ratio.

Edge-Rich 3D Structuring of Metal Chalcogenide/Graphene with Vertical Nanosheets for Efficient Photocatalytic Hydrogen Production.

Constructing pertinent nanoarchitecture with abundant exposed active sites is a valid strategy for boosting photocatalytic hydrogen generation. However, the controllable approach of an ideal architecture comprising vertically standing transition metal chalcogenides (TMDs) nanosheets on a 3D graphene network remains challenging despite the potential for efficient photocatalytic hydrogen production. In this study, we fabricated edge-rich 3D structuring photocatalysts involving vertically grown TMDs nanosheets on a 3D porous graphene framework (referred to as 3D Gr). 2D TMDs (MoS2 and WS2)/3D Gr heterostructures were produced by location-specific photon-pen writing and metal-organic chemical vapor deposition for maximum edge site exposure enabling efficient photocatalytic reactivity. Vertically aligned 2D Mo(W)S2/3D Gr heterostructures exhibited distinctly boosted hydrogen production because of the 3D Gr caused by synergetic impacts associated with the large specific surface area and improved density of exposed active sites in vertically standing Mo(W)S2. The heterostructure involving graphene and TMDs corroborates an optimum charge transport pathway to rapidly separate the photogenerated electron-hole pairs, allowing more electrons to contribute to the photocatalytic hydrogen generation reaction. Consequently, the size-tailored heterostructure showed a superior hydrogen generation rate of 6.51 mmol g-1 h-1 for MoS2/3D graphene and 7.26 mmol g-1 h-1 for WS2/3D graphene, respectively, which were 3.59 and 3.76 times greater than that of MoS2 and WS2 samples. This study offers a promising path for the potential of 3D structuring of vertical TMDs/graphene heterostructure with edge-rich nanosheets for photocatalytic applications.

Pt1.8Pd0.2CuGa Intermetallic Nanocatalysts with Enhanced Methanol Oxidation Performance for Efficient Hybrid Seawater Electrolysis.

Seawater electrolysis is a potentially cost-effective approach to green hydrogen production, but it currently faces substantial challenges for its high energy consumption and the interference of chlorine evolution reaction (ClER). Replacing the energy-demanding oxygen evolution reaction (OER) with the methanol oxidation reaction (MOR) represents a promising alternative, as the MOR occurs at a significantly low anodic potential, which cannot only reduces the voltage needed for electrolysis but also completely circumvents the ClER. To this end, developing high-performance MOR catalysts is a key. Herein, we report a novel quaternary Pt1.8Pd0.2CuGa/C intermetallic nanoparticles (i-NPs) catalyst, which shows a high mass activity (11.13 A mgPGM -1), a large specific activity (18.13mA cmPGM -2), and outstanding stability toward alkaline MOR. Advanced in-situ surface-enhanced Raman spectroscopy (SERS), online differential mass spectrometry (DEMS) and density functional theory (DFT) calculations reveal that the introduction of atomically distributed Pd in Pt2CuGa intermetallic markedly promotes the oxidation of key reaction intermediates by enriching electron concentration around Pt sites, resulting in weak adsorption of carbon-containing intermediates and favorable adsorption of the synergistic OH- groups near Pd sites. Using Pt1.8Pd0.2CuGa/C i-NPs as anodic catalysts, we demonstrate MOR-assisted seawater electrolysis that continuously operates under 1.23V for 240h in simulated seawater and 120h in natural seawater without notable degradation, showing great potential for energy-saving and cost-competitive hydrogen production from seawater. This article is protected by copyright. All rights reserved.

Molecular Engineering for Modulating Photocatalytic Hydrogen Evolution of Fully Conjugated 3D Covalent Organic Frameworks

AbstractCovalent organic frameworks (COFs) have recently shown great potential for photocatalytic hydrogen production. Currently almost all reports are focused on two‐dimensional (2D) COFs, while the 3D counterparts are rarely explored due to their non‐conjugated frameworks derived from the sp3 carbon based tetrahedral building blocks. Here, we rationally designed and synthesized a series of fully conjugated 3D COFs by using the saddle‐shaped cyclooctatetrathiophene derivative as the building block. Through molecular engineering strategies, we thoroughly discussed the influences of key factors including the donor‐acceptor structure, hydrophilicity, specific surface areas, as well as the conjugated/non‐conjugated structures on their photocatalytic hydrogen evolution properties. The as‐synthesized fully conjugated 3D COFs could generate the hydrogen up to 40.36 mmol h−1 g−1. This is the first report on intrinsic metal‐free 3D COFs in photocatalytic hydrogen evolution application. Our work provides insight on the structure design of 3D COFs for highly‐efficient photocatalysis, and also reveals that the semiconducting fully conjugated 3D COFs could be a useful platform in clear energy‐related fields.

Molecular Engineering for Modulating Photocatalytic Hydrogen Evolution of Fully Conjugated 3D Covalent Organic Frameworks.

Covalent organic frameworks (COFs) have recently shown great potential for photocatalytic hydrogen production. Currently almost all reports are focused on two-dimensional (2D) COFs, while the 3D counterparts are rarely explored due to their non-conjugated frameworks derived from the sp3 carbon based tetrahedral building blocks. Here, we rationally designed and synthesized a series of fully conjugated 3D COFs by using the saddle-shaped cyclooctatetrathiophene derivative as the building block. Through molecular engineering strategies, we thoroughly discussed the influences of key factors including the donor-acceptor structure, hydrophilicity, specific surface areas, as well as the conjugated/non-conjugated structures on their photocatalytic hydrogen evolution properties. The as-synthesized fully conjugated 3D COFs could generate the hydrogen up to 40.36 mmol h-1 g-1. This is the first report on intrinsic metal-free 3D COFs in photocatalytic hydrogen evolution application. Our work provides insight on the structure design of 3D COFs for highly-efficient photocatalysis, and also reveals that the semiconducting fully conjugated 3D COFs could be a useful platform in clear energy-related fields.

Techno-economic analysis of a novel concept for the combination of methane pyrolysis in molten salt with heliostat solar field

Methane pyrolysis has emerged as a promising low-carbon hydrogen production method, serving as a bridge from conventional fossil fuels to renewable energies (REs). A recent technique for sustainable hydrogen production involves the process of methane pyrolysis in molten salt. To better understand the potential of sustainable turquoise hydrogen production, this paper presents a techno-economic assessment of methane pyrolysis in molten salt combined with a high-temperature heliostat solar field. In addition, a high-temperature thermal energy storage (HTES) unit is utilized to ensure uninterrupted hydrogen production during periods of solar unavailability, thereby contributing to the economic viability of the overall system. The proposed system can produce about 9 tons of H2/day and 27 tons of solid carbon/day with a round-trip efficiency of 49.8 % and a levelized cost of hydrogen (LCOH) of 1.93 $/kg. To further decarbonize the process, the feasibility of utilizing REs as the source of electricity for the HTES was analyzed, yielding a synergistic achievement of clean and economic hydrogen production. This configuration resulted in a LCOH of 1.25 $/kg, after including the United States (US) clean hydrogen production tax incentives. The proposed system shows the potential to achieve the US Department of Energy target of 1 $/kg of hydrogen with a 20 % reduction in the cost of RE infrastructure.

Effect of recycled polyethylene catalyst for Mediterranean pine seed shell biomass pyrolysis on hydrogen and methane production

ABSTRACT The present study exhibits the potential of hydrogen and methane gases production from the Mediterranean pine tree seed shell biomass over recycled polyethylene wastes as catalyst. In the study, firstly, the viscosity and density of polyethylene materials and degassing point were determined. The pyrolysis was carried out at a rate of 50 °C/min at 600°C temperature. The obtained gases were analyzed with gas chromatography device. At the last step of the experiments, solid residues were observed under an optical microscope, and their microstructures were also examined. The results showed that Mediterranean pine seed shell biomass and its mixture with low-density polyethylene may produce methane and hydrogen gases. M8 catalyst, which has one of the lowest viscosity values (0.45 gr/10 min.) and highest density values (0.950 gr/cm3) produced the highest methane and hydrogen gas yields. In the pyrolysis experiments, 38.44% CH4, 19.50% CO2 and 42.06% H2 gases were obtained from Mediterranean pine seed shell biomass. Moreover, CO2 emission values of biomass were calculated and compared with DEFRA values. The study demonstrated that, since hydrogen and methane can be obtained through the pyrolysis process, Mediterranean pine tree seed shell can be classified as a new biomass source and has potential to alternative fuel to fossil-based fuels for internal combustion engines.

Cascade utilization of full spectrum solar energy for achieving simultaneous hydrogen production and all-day thermoelectric conversion

Solar-driven photocatalytic water/seawater splitting holds great potential for green hydrogen production. However, the practical application is hindered by the relatively low conversion efficiency resulting from the inadequate utilization of solar spectrum with significant waste in the form of heat. Moreover, current equipment struggles to maintain all-day operation subjected to the lack of light during nighttime. Herein, a novel hybrid system integrating photothermal catalytic (PTC) reactor, thermoelectric generator (TEG), and phase change materials (PCM) was proposed and designed (named as PTC-TEG-PCM) to address these challenges and enable simultaneous overall seawater splitting and 24-hour power generation. The PTC system effectively maintains in an optimal temperature range to maximize photothermal-assisted photocatalytic hydrogen production. The TEG component recycles the low-grade waste heat for power generation, complementing the shortcoming of photocatalytic conversion and achieving cascade utilization of full-spectrum solar energy. Furthermore, exceptional thermal storage capability of PCM allow for the conversion of released heat into electricity during nighttime, contributing significantly to the overall power output and enabling PTC-TEG-PCM to operate for more than 12 h under the actual condition. Compared to traditional PTC system, the overall energy conversion efficiency of the PTC-TEG-PCM system can be increased by ∼500%, while maintaining the solar-to-hydrogen efficiency. The advancement of this novel system demonstrated that recycling waste heat from the PTC system and utilizing heat absorption/release capability of PCM for thermoelectric application are effective strategies to improve solar energy conversion. With flexible parameter designing, PTC-TEG-PCM can be applied in various scenarios, offering high efficiency, stability, and sustainability.

Leveraging bifunctional phosphide-based catalysts in a membrane-electrode-assembly to achieve industrial hydrogen production

The advancement of the hydrogen economy hinges upon the development of clean, cost-effective, and highly efficient hydrogen generators capable of industrial-scale operation. Conventional electrolyzers encounter challenges such as high internal resistance and low current density, which restrict their practical applicability. In this study, we present a cost-effective bifunctional CoFeP electrocatalyst wherein the regulation of cobalt 3d orbitals by iron dopants enhances overall catalytic activity. High-energy-resolution fluorescence-detection X-ray absorption spectroscopy and 1s3p resonant inelastic X-ray scattering confirm a downward shift and delocalization of cobalt ion 3d orbitals. Employed within a membrane-electrode assembly (MEA) system, CoFeP demonstrates voltages of 1.51 V at 10 mA cm−2, 1.65 V at 100 mA cm−2 and 2.11 V at 500 mA cm−2 without iR-correction. These values are significantly lower by 109 mV and 470 mV than those recorded at 100 mA cm−2 (1.62 V) and 500 mA cm−2 (2.71 V), respectively, in a conventional H-cell system. Within the MEA system, CoFeP achieves a Faradaic efficiency exceeding 97% for hydrogen production and sustains stable catalytic for 350 h, underscoring its potential for industrial-scale hydrogen production.

Downsizing nanoarchitectonics of multilayered MXenes electrocatalysts towards real time ion tracking via EQCM and electrocatalytic applications

Since their discovery, engineering two-dimensional (2D) MXene materials have attracted rapid interest in both energy storage and conversion applications. Among the several techniques being introduced for enhancing material properties, downsizing is one among the interesting approaches. Downsizing involves the deliberate scaling down of active 2D materials, such as MXenes, systematically. Although major studies are focused on the electrochemical applications of single layered MXene flakes, curiosity in evaluating the downsized multilayered MXenes for electrochemical applications motivates this project. Thus, in the current study, the multilayered bulk MXenes are sequentially stepped down to smaller multilayered fragments at definite time intervals, and subsequently the potential of this procured heterogeneous polydispersed solution are evaluated towards electrochemical applications without any further post-treatments. Real time monitoring of lithium-ion exchange in the downsized MXene materials at various time intervals was tracked using the electrochemical quartz crystal microbalance technique, where the downsized MXene system exhibited water-assisted lithium-ion transfer behavior. Increase in mass exchange was found to increase with increase in downsized MXene systems, thus making it very interesting towards ion storage applications. Further, downsized MXene electrocatalyst material delivered the lowest onset potential for hydrogen production among the set of catalysts studied. In short, this study outlines and pioneers some interesting observations regarding both energy storage and catalytic applications of multilayered downsized MXenes, thereby opening up new possibilities for facile, rapid and cost-effective material fabrication approaches.

(Bio)electrochemical system: A systematic approach from agricultural waste to sewage wastewater treatment with nutrients and hydrogen recovery

Sustainable biowaste utilization is currently an interesting research area to enhance its conversion to value-added products. Electrochemical and bioelectrochemical technologies are cracking up the fractionization of various types of waste for environmental cleanup processes. In the present study, agricultural waste-based extracted material was used to capture the nutrients and/or pollutants from the anaerobic bioelectrochemically treated sewage wastewater (SWW). Hydrogen production potential of 15.52–11.77 times higher than the single carbon source indicated efficient utilization of organic and inorganic matters by extant microorganisms in the SWW. The electrochemical hemicellulose (HC) extraction, nutrient recovery and other components like applied potential (mV), NaOH (M) and rice straw load (%) analysis were evaluated at three factors and three levels. The N/C ratio of 0.06 and the highest functionalities in the 150-mV extracted HC, confirm its suitability to trap nutrients/pollutants from wastewater. With the potential to substitute expensive adsorbents in the future, the additional advantage of HCs being useful in the recovery of ammonium ions for use in agriculture could positively impact the global food security program. The aim of the study is not only the recovery of nutrients from waste but also to unravel the clean path of waste management with possible green energy production.

Performance evaluation of the Fe–Cl and Mg–Cl cycle for hydrogen production of the minor actinide fuelled PACER fusion blanket

Thermochemical processes used to produce clean hydrogen (H2) on a large scale by utilizing renewable energy and nuclear power sources are considered one of the most environmentally friendly strategies. In this study, the neutronic performance and hydrogen production potential of the PACER fusion blanket have been investigated during the operation period. Firstly, neutronic calculations have been performed to produce an electrical energy of 1000 MW from fusion explosions of 8.36 TJ to be repeated every 40 min with Monte Carlo Calculation Method (MCNP). Minor actinide flouride (MA) fuel out of the nuclear waste of LWRs with volume fractions of 2% have been mixed homogenously in the Flibe coolant. Tritium breeding ratio (TBR) at startup is calculated as 1.27. TBR and energy multiplication factor (M) decrease gradually. TBR >1.05 can be kept over 7 years for a self-sustained reactor. The M due to higher fissionable fuel content in the molten salt computes as 3.3 at initial. The burn up exceeds ∼800 GWd/tM at the end of operation period. Secondly, the potential of hydrogen production for four step iron chloride (Fe–Cl) and three step magnesium chloride (Mg–Cl) thermochemical cycles of the hydrogen unit PACER fusion blanket. The ratio of thermal power (1 − ψ), total thermal power (Phpf) and rate of mass flow of hydrogen (m˙H2) depends on M for Fe–Cl, Mg–Cl (option I) and Mg–Cl (option II) thermochemical cycle have been presented. The ratio of thermal power (1 − ψ) for Fe–Cl, Mg–Cl (option I) and Mg–Cl (option II) have been obtained as 0.6494, 0.131 and 0.095 whereas, total thermal power (Phpf) have been computed as 5298.8, 3608.43 and 3488.925 MW, respectively, at start up. The produced of hydrogen amount for Fe–Cl, Mg–Cl (option I) and Mg–Cl (option II) have been calculated as ∼ 534.65; ∼1236.82 and ∼806.03 kg/year, respectively, at startup.

Hydrogen generation from methanolysis of sodium borohydride using boric acid as a catalyst

ABSTRACT Hydrogen plays a critical role in reducing dependence on fossil fuels and combating climate change as a clean, highly efficient, and renewable energy source. In this study, hydrogen production via methanolysis of sodium borohydride (NaBH4) has been investigated in the presence of boric acid (H3BO3) catalyst. The effect of various parameters on hydrogen generation rate has been reported and the effect of temperature, H3BO3 catalyst concentration, methanol volume and NaBH4 concentration has been studied in the range of 20–50°C, 0.539–2.695 mM, 2–20 mL, and 0.176–0.881 mM, respectively. The kinetic parameters are estimated with the power law model and the reaction order and activation energy are found as 2 and 33.25 kJ·mol−1, respectively. The highest hydrogen generation rate (HGR) is achieved as 628,117 mL·min−1·g cat−1 at 50°C with 1.078 mM H3BO3 and 0.352 M NaBH4 concentrations and 15 mL methanol volume. This study’s notable result is the emphasis on the effect of using a very small amount of boric acid. Because the use of a high amount of boric acid as a catalyst causes steric hindrance in the methanolysis reaction of trimethyl borate, which is the product of the equilibrium reaction between boric acid and excess alcohol in the solution. This situation has been avoided by using a lower amount of boric acid. Thus, it demonstrates that environmentally friendly, efficient, and cost-effective boric acid has great potential in hydrogen production via methanolysis and that its performance can be further improved with more work on the optimization of catalyst concentration.

A comprehensive 3D modelling exploration of a protonic ceramic electrolysis cell stack with metal foam

Protonic ceramic electrolysis cells (PCECs) offer significant potential for large-scale green hydrogen production. The performance of conventional PCEC stacks is notably limited due to the uneven gas distribution. In this research, a new stack design using metal foam as the gas distributor is proposed and numerically evaluated using a 3D Multiphysics model to improve the gas distribution uniformity. At 1.3 V and 600 °C, the current density of the newly designed PCEC with metal foam is 173 % higher than that of the conventional PCEC. Moreover, the hydrogen production capability of metal foam based PCEC is 234 % higher than that of conventional PCEC, due to the improved gas distribution uniformity and faradaic efficiency (FE) of the new PCEC. The application of metal foam increases steam distribution uniformity by 91.2 %. In a conventional PCEC, the FE under the rib is notably lower than that under the channel. In contrast, the FE distribution is more uniform in a metal foam based PCEC. The improved performance in terms of current density, FE, and distribution uniformity highlights the potential of metal foam as a beneficial component in PCEC stacks. These findings contribute to the understanding and further development of PCEC technology.

Magnetism and electronic properties of ConMoP (n = 1 ~ 5) cluster: a DFT study.

Hydrogen has emerged as a promising clean energy carrier, underscoring the imperative need to comprehend its adsorption mechanisms. This study delves into the magnetic and electronic properties of Co-Mo-P clusters, aiming to unveil their catalytic potential in hydrogen production. Employing density functional theory (DFT), we optimized cluster configurations and scrutinized their magnetic behaviors. Our investigation unveiled 16 stable configurations of the ConMoP (n = 1 ~ 5) cluster, predominantly in steric forms. The magnetic attributes were primarily ascribed to the d orbitals of Co metal atoms, with Co3MoP exhibiting exceptional magnetic characteristics. Analysis of density of state diagrams revealed the prevalence of spin-up α-electrons in d orbitals, while spin-down β-electrons attenuated overall magnetic properties. Localized orbital (LOL) analysis highlighted stable covalent bonds within the clusters, affirming their catalytic potential. Orbital delocalization index (ODI) analysis revealed diverse spatial distribution ranges for orbitals across different configurations, suggesting a progressive attenuation of off-domain properties with increasing cluster size. Furthermore, infrared spectroscopy unveiled distinct vibrational peaks in various configurations, indicative of unique infrared activities. These findings contribute to a nuanced theoretical understanding of Co-Mo-P clusters and pave the path for future research aimed at augmenting their catalytic efficiency in hydrogen production. This study underscores the viability of Co-Mo-P clusters as alternatives to conventional Pt catalysts, offering insights into the design of novel materials for sustainable energy applications. Further research is warranted to explore the behavior of the Co-Mo-P system under diverse reaction conditions, fostering advancements in materials and energy science. In this study, we harnessed the ConMoP (n = 1 ~ 5) cluster as a simulation platform for probing the local structure of the material. Our aim was to scrutinize the magnetism, electronic characteristics influenced by the varying metal atoms within these clusters. A systematic exploration involved incrementing the number of metal atoms and expanding the cluster size to elucidate the corresponding property variations. Density functional theory (DFT) calculations were pivotal to our methodology, employing the B3LYP hybrid functional implemented in the Gaussian16 software package. The ConMoP (n = 1 ~ 5) cluster underwent optimization calculations and vibrational analysis at the def2-tzvp quantization level, yielding optimized configurations with diverse spin multiplet degrees. To comprehensively characterize and visually represent the stability, electronic features, and catalytic attributes of these configurations, we employed a suite of computational tools. Specifically, quantum chemistry software GaussView and wave function analysis software Multiwfn played integral roles. Through the integrated use of these computational tools, we acquired valuable insights into the magnetism, electronic characteristics of the ConMoP (n = 1 ~ 5) cluster, shedding light on their dependency on distinct metal atoms.

Emerging Photoreforming Process to Hydrogen Production: A Future Energy

AbstractIn the quest of renewable energy technologies, solar photoreforming emerges as one of the affordable yet challenging process for converting biomass into hydrogen, hydrocarbon fuels, and chemicals. This review highlights the state‐of‐the‐art photoreforming, elucidating its underlying mechanisms for the conversion of dissipated polymers into H2 and valuable chemicals. Biomass feedstocks such as carbohydrates, agricultural residues, glycopolymers, food wastes, and waste plastics are evaluated based on their chemical composition, energy content, and sustainability aspects, exploring the selection of appropriate bio‐renewable resources, considering their abundance, availability, and potential for hydrogen production. The impact of diverse process parameters on photoreforming efficiency is explored, encompassing factors like reaction temperature, pH, catalyst loading, reactor design, solvent effect, and light intensity across various sacrificial substrates. The discussion also considers their correlation with hydrogen production rate, selectivity, and energy efficiency. This review buckles on the design and synthesis of functional photocatalysts for biomass‐derived feedstock, highlighting their photocatalytic (PC) properties in biomass reforming processes and related feedstock into valuable chemicals and biofuel. The review also delves into potential pathways for future advancements including artificial intelligence (AI) and machine learning (ML), alongside addressing the challenges and insightful perspectives within this evolving field of future green energy.

TODAY'S REALITIES AND PROSPECTS OF THE FUTURE DEVELOPMENT OF HYDRO ENERGY IN THE WORLD AND IN UKRAINE

Traditional fossil fuels have a detrimental effect on the global environmental situation, which leads to stricter standards for environmental protection. Therefore, in recent years there has been a need to develop and master new technologies that make it possible to generate, store and transmit energy without or while minimizing emissions of greenhouse gases into the atmosphere, primarily CO2, which is referred to as the so-called “carbon footprint”. An emerging branch of global energy - hydrogen energy - is based on the use of a compound such as hydrogen as a means for accumulating, transporting, producing and consuming energy. Hydrogen is expected to transform the economy in four main application areas: transportation, industry, energy and utilities. The purpose of this review is to analyze the main trends and criteria for the successful development of global hydrogen energy, as well as to consider the state and prospects for the development of the emerging global and Ukrainian hydrogen energy markets. The article analyzes the development of the hydrogen energy market, discusses national programs to support this new branch of world energy and pilot hydrogen projects. Issues of production, consumption, accumulation, storage and transportation of hydrogen are considered. Ukraine is one of the EU's priority partners in the future hydrogen economy, as it has the necessary capacity for hydrogen production - both for domestic consumption and for export. In 2021, the Ministry of Energy of Ukraine joined the European Pure Hydrogen Alliance. Ukraine's potential for hydrogen production is currently being investigated. The possibility of using the national GTS for hydrogen transportation to Europe is also being studied. The results of the targeted comprehensive program of scientific research of the National Academy of Sciences of Ukraine regarding the creation of new materials, technological processes, structures and systems that could become the basis for the widespread introduction of hydrogen technologies in Ukraine are presented. An assessment of the state of the global and Ukrainian hydrogen markets and the prospects for their development in the coming years is provided.

Negative net global warming potential hydrogen production through biomass gasification combined with chemical looping: Environmental and economic assessments

The integration of biomass gasification (BG) with chemical looping hydrogen production (CLHP) offers one prospective approach for green hydrogen production. The environmental and economic assessments are conducted to evaluated the sustainable performance of the BG-CLHP system during the hydrogen production cycle (HPC). The results showed that the environmental impacts of BG-CLHP are concentrated in freshwater aquatic ecotoxicity (FAETP), human toxicity (HTP), and acidification (AP). The BG-CLHP system can provide a more cost-competitive hydrogen supply solution for hydrogen refueling stations compared the offshore wind or photovoltaic (PV) powered electrolysis, given the same hydrogen production target. For global warming potential (GWP) and cost, the BG-CLHP demonstrates excellent integrated performance with GWP values of −15.13 and −17.00 kg CO2, eq/kg H2, for the Air case and Oxygen case, and the costs of 3.05 and 2.82 $/kg H2, respectively, and sensitivity analysis reveals that the CLHP stage is the primary contributor to GWP. Compared with existing hydrogen production routes, BG-CLHP can still be improved in terms of costs and the technical maturity, however, the excellent negative GWP properties of BG-CLHP make it will play a more important role in future large-scale hydrogen production.

Biohydrogen production by co-digestion of food waste and corn industry wastewater

Food waste (FW) and corn industry wastewater (cornWW) are residues with a high potential for hydrogen production in the dark fermentation process. The study aimed to identify the co-digestion of FW and cornWW ratios for improving hydrogen production and evaluating the synergistic effect on biohydrogen production potential (BHP) in batch test. The inoculum consisted of a mixed culture plus the native microbiota of each substrate. The adjustment of the initial pH to 7.5 was compared to the co-digestion without control of the initial pH of the experiments. The highest hydrogen and metabolites production were obtained with a co-digestion FW:cornWW ratio. When no pH adjustment is applied, pH values above 10 completely inhibit the metabolic activity of bacteria in the process. The cornWW not only provided alkalinity to the system but also can be applied to adjust the organic matter content of FW, adjusting the initial concentration of organic matter. The growth of microbial communities was formed mainly by Clostridium sp. The co-digestion of FW:cornWW can be technically feasible to improve the production of H2 through the dark fermentation process.