India

Hydrogen is seen as an important future energy carrier as part of the move away from traditional hydrocarbon sources. Delayed ignition of a hydrogen-air mixture formed from an accidental release of hydrogen in either a confined or congested environment can lead to the generation of overpressure impacting both people and assets. An understanding of the possible overpressures generated is critical in designing facilities and effective mitigation systems against hydrogen explosion hazards. This paper describes the numerical modelling of hydrogen deflagrations using a new application PDRFOAM-R that is part of the wider OpenFOAM open-source CFD package of routines for the solution of systems of partial differential equations. The PDRFOAM-R code solves momentum and continuity equations the combustion model is based on flame area transport and the turbulent burning velocity correlation is based on Markstein and Karlovitz numbers. PDRFOAM-R is derived from publicly available PDRFOAM tool and it resolves small and large obstacles unlike PDRFOAM which is based on the Porosity Distributed Resistance approach. The PDRFOAM-R code is validated against various unconfined-uncongested and semi-confined congested explosion experiments. The flame dynamics and pressure history predicted from the simulation show a reasonable comparison with the experiments.

Presently the fulfilment of world’s energy demand highly relies on the fossil fuel i.e. coal oil and natural gas. Fossil fuels pose threat to environment and biological systems on the earth. Usage of these fuels leads to an increase in the CO2 content in the atmosphere that causes global warming and undesirable climatic changes. Additionally these are limited sources of energy those will eventually dwindle. There is huge urge of identifying and utilizing the renewable energy resources to replace these fossil fuels in the near future as it is expected to have no impact on environment and thus would enable one to provide energy security. Hydrogen is one of the most desirable fuel capable of replacing vanishing hydrocarbons. In this review we present the status of energy demands recent advances in renewable energy and the prospects of hydrogen as a future fuel are highlighted. It gives a broad overview of different energy systems and mainly focuses on different technologies and their reliability for the production of hydrogen in present and future.

Hydrogen is the most efficient energy carrier. Hydrogen can be obtained from different sources of raw materials including water. Among many hydrogen production methods eco-friendly and high purity of hydrogen can be obtained by water electrolysis. However In terms of sustainability and environmental impact PEM water electrolysis was considered as most promising techniques for high pure efficient hydrogen production from renewable energy sources and emits only oxygen as byproduct without any carbon emissions. Moreover the produced hydrogen (H₂) and oxygen (O₂) directly used for fuel cell and industrial applications. However overall water splitting resulting in only 4% of global industrial hydrogen being produced by electrolysis of water mainly due to the economic issues. Nowadays increased the desire production of green hydrogen has increased the interest on PEM water electrolysis. Thus the considerable research has been completed recently in the development of cost effective electrocatalysts for PEM water electrolysis. In this present review we discussed about the recent developments in the PEM water electrolysis including high performance low cost HER and OER electrocatalysts and their challenges new and old related to electrocatalysts and PEM cell components also addressed. This review will contribute further research improvements and a road map in order to support in developing the PEM water electrolyser as a commercially feasible hydrogen production purpose.

In the transition to a climate neutral future the transportation sector needs to be sustainably decarbonized. Producing advanced fuels (such as biomethane) and bio-based valorised products (such as pyrochar) may offer a solution to significantly reduce greenhouse gas (GHG) emissions associated with energy and agricultural circular economy systems. Biological and thermochemical bioenergy technologies together with power to gas (P2G) systems can generate green renewable gas which is essential to reduce the GHG footprint of industry. However each technology faces challenges with respect to sustainability and conversion efficiency. Here this study identifies an optimal pathway leading to a sustainable bioenergy system where the carbon released in the fuel is offset by the GHG savings of the circular bio-based system. It provides a state-of-the-art review of individual technologies and proposes a bespoke circular cascading bio-based system with anaerobic digestion as the key platform integrating electro-fuels via P2G systems and value-added pyrochar via pyrolysis of solid digestate. The mass and energy analysis suggests that a reduction of 11% in digestate mass flow with the production of pyrochar bio-oil and syngas and an increase of 70% in biomethane production with the utilization of curtailed or constrained electricity can be achieved in the proposed bio-based system enabling a 70% increase in net energy output as compared with a conventional biomethane system. However the carbon footprint of the electricity from which the hydrogen is sourced is shown to be a critical parameter in assessing the GHG balance of the bespoke system.

In FY-20 India’s steel production was 109 MT and it is the second-largest steel producer on the planet after China. India’s per capita consumption of steel was around 75 kg which has risen from 59 kg in FY-14. Despite the increase in consumption it is much lower than the average global consumption of 230 kg. The per capita consumption of steel is one of the strongest indicators of economic development across the nation. Thus India has an ambitious plan of increasing steel production to around 250 MT and per capita consumption to around 160 kg by the year 2030. Steel manufacturers in India can be classified based on production routes as (a) oxygen route (BF/BOF route) and (b) electric route (electric arc furnace and induction furnace). One of the major issues for manufacturers of both routes is the availability of raw materials such as iron ore direct reduced iron (DRI) and scrap. To achieve the level of 250 MT steel manufacturers have to focus on improving the current process and product scenario as well as on research and development activities. The challenge to stop global warming has forced the global steel industry to strongly cut its CO2 emissions. In the case of India this target will be extremely difficult by ruling in the production duplication planned by the year 2030. This work focuses on the recent developments of various processes and challenges associated with them. Possibilities and opportunities for improving the current processes such as top gas recycling increasing pulverized coal injection and hydrogenation as well as the implementation of new processes such as HIsarna and other CO2 -lean iron production technologies are discussed. In addition the eventual transition to hydrogen ironmaking and “green” electricity in smelting are considered. By fast-acting improvements in current facilities and brave investments in new carbon-lean technologies the CO2 emissions of the Indian steel industry can peak and turn downward toward carbon-neutral production.

In the climate change mitigation context based on the blue hydrogen concept a narrative frame is presented in this paper to build the argument for solving the energy trilemma which is the possibility of job loss and stranded asset accumulation with a sustainable energy solution in gas- and oil-rich regions especially for the Persian Gulf region. To this aim scientific evidence and multidimensional feasibility analysis have been employed for making the narrative around hydrogen clear in public and policy discourse so that choices towards acceleration of efforts can begin for paving the way for the future hydrogen economy and society. This can come from natural gas and petroleum-related skills technologies experience and infrastructure. In this way we present results using multidimensional feasibility analysis through STEEP and give examples of oil- and gas-producing countries to lead the transition action along the line of hydrogen-based economy in order to make quick moves towards cost effectiveness and sustainability through international cooperation. Lastly this article presents a viewpoint for some regional geopolitical cooperation building but needs a more full-scale assessment.

The graphene oxide @nickel phosphate (GO:NPO) nanocomposites (NCs) are prepared by using a one-pot in-situ solar energy assisted method by varying GO:NPO ratio i.e. 0.00 0.25 0.50 0.75 1.00 1.25 1.50 and 2.00 without adding any surfactant or a structure-directing reagent. As produced GO:NPO nanosheets exhibited an improved photocatalytic activity due to the spatial seperation of charge carriers through interface where photoinduced electrons transferred from NiPO4 to the GO sheets without charge-recombination. Out of the series the system 1.00 GO:NPO NC show the optimum hydrogen production activity (15.37 μmol H2 h−1) towards water splitting under the visible light irradiation. The electronic environment of the nanocomposite GO-NiO6/NiO4-PO4 elucidated in the light of advance experimental analyses and theoretical DFT spin density calculations. Structural advanmcement of composites are well correlated with their hydrogen production activity.

In the field of energy storage recently investigated nanocomposites show promise in terms of high hydrogen uptake and release with enhancement in the reaction kinetics. Among several carbonaceous nanovariants like carbon nanotubes (CNTs) fullerenes and graphitic nanofibers reveal reversible hydrogen sorption characteristics at 77 K due to their van der Waals interaction. The spillover mechanism combining Pd nanoparticles on the host metal-organic framework (MOF) show room temperature uptake of hydrogen. Metal or complex hydrides either in the nanocomposite form and its subset nanocatalyst dispersed alloy phases illustrate the concept of nanoengineering and nanoconfinement of particles with tailor-made properties for reversible hydrogen storage. Another class of materials comprising polymeric nanostructures such as conducting polyaniline and their functionalized nanocomposites are versatile hydrogen storage materials because of their unique size high specific surface-area pore-volume and bulk properties. The salient features of nanocomposite materials for reversible hydrogen storage are reviewed and discussed.

In this work methanol decomposition method has been discussed for the production of hydrogen gas with the application of plasma. A simple dielectric barrier discharge (DBD) plasma reactor was designed for this purpose with two types of electrode. The DBD plasma reactor was experimented by substituting one of the metal electrodes with feebly conducting sea water which yielded better efficiency in producing hydrogen gas. Experimental parameters such as; discharge voltage and time were varied by maintaining a discharge gap of 1.5 mm and the plasma discharge characteristics were studied. Filamentary type micro-discharges were found to be formed which was observed as numerous streamer clusters in the current waveform. Gas chromatographic study confirmed the production of hydrogen gas with residence time around 3.6 min. Although the concentration (%) of H2 was high (98.1 %) and consistent with copper electrode assembly the rate of formation and concentration was found to be the highest (98.7 %) for water electrode for specific discharge voltage. The energy efficiency was found to be 0.5 mol H2/kWh and 1.2 mol H2/kWh for metal (Cu) and water electrodes respectively. The electrode material significantly affects the plasma condition and hence the rate of hydrogen production. Compositional analysis of the water used as electrode showed a minimal change in the composition even after the completion of the experiment as compared to the untreated water. Methanol degradation study shows the presence of untreated methanol in the residue of the plasma reactor which has been confirmed from the absorption spectra.

It is a common belief that embedded expanding inclusions are subjected to an internal homogeneous compressive hydrostatic stress. Still cracks that appear in precipitates that occupy a larger volume than the original material are frequently observed. The appearance of cracks has since long been regarded as a paradox. In the present study it is shown that matrix materials that increases its volume even several percent during the precipitation process develop a tensile hydrostatic stress in the centre of the precipitate. This is the result of a complicated mechanical-chemical phase transformation process. The process is here studied using a Landau phase feld model. Before the material is transformed and incorporated in a precipitate it undergoes stretching beyond the elastic strain limit because of the presence of already expanded material. During the phase transformation the accompanying volumetric expansion cannot be fully accommodated which instead creates an internal compressive stress and adds tension in the surrounding material. As the growth of the precipitate proceeds a region with increasing tensile stress develops in the interior of the precipitate. This is suggested to be the most probable cause of the observed cracks. First the mechanics that lead to the tension is computed. The infuence of elastic-plastic properties is studied both for cases both with and without cracks. The growth history from microscopic to macroscopic precipitates is followed and the result is compared with observations of so called hydride blisters that are formed on surfaces of zirconium alloys in the presence of hydrogen. A common practical situation is when the zirconium is in contact with an object of lower temperature. Then the cooled spot attracts hydrogen that make the zirconium transform to a metal hydride with the shape of a blister. The simulations predicts a final size and position of the growing crack that compares well with the experimental observations.

About 400 million tonnes of plastics are produced per annum worldwide. End-of-life of plastics disposal contaminates the waterways aquifers and limits the landfill areas. Options for recycling plastic wastes include feedstock recycling mechanical /material recycling industrial energy recovery municipal solid waste incineration. Incineration of plastics containing E-Wastes releases noxious odours harmful gases dioxins HBr polybrominated diphenylethers and other hydrocarbons. This study focusses on recycling options in particular feedstock recycling of plastics in high-temperature materials processing for a sustainable solution to the plastic wastes not suitable for recycling. Of the 7% CO₂ emissions attributed to the iron and steel industry worldwide ∼30% of the carbon footprint is reduced using the waste plastics compared to other carbon sources in addition to energy savings. Plastics have higher H₂ content than the coal. Hydrogen evolved from the plastics acts as the reductant alongside the carbon monoxide. Hydrogen reduction of iron ore in presence of plastics increases the reaction rates due to higher diffusion of H₂ compared to CO. Plastic replacement reduces the process temperature by at least 100–200 °C due to the reducing gases (hydrogen) which enhance the energy efficiency of the process. Similarly plastics greatly reduce the emissions in other high carbon footprint process such as magnesia production while contributing to energy.

Hydrogen is emerging as a new energy vector outside of its traditional role and gaining more recognition internationally as a viable fuel route. This review paper offers a crisp analysis of the most recent developments in hydrogen production techniques using conventional and renewable energy sources in addition to key challenges in the production of Hydrogen. Among the most potential renewable energy sources for hydrogen production are solar and wind. The production of H2 from renewable sources derived from agricultural or other waste streams increases the flexibility and improves the economics of distributed and semi-centralized reforming with little or no net greenhouse gas emissions. Water electrolysis equipment driven by off-grid solar or wind energy can also be employed in remote areas that are away from the grid. Each H2 manufacturing technique has technological challenges. These challenges include feedstock type conversion efficiency and the need for the safe integration of H2 production systems with H2 purification and storage technologies.

NiCu alloy catalysts with varying composition for electrolysis in alkaline water have been prepared by DC magnetron co-sputtering under Ar gas environment at substrate bias of  60 V. Nanocrystallinity lattice parameters and grain size of the NiCu alloys have been measured by grazing incidence X-ray diffraction (GIXRD). Elemental and microstructural analysis of the NiCu alloy have been done by field emission scanning electron microscopy (FESEM) as well as transmission electron microscopy (TEM). To analyze the NiCu alloys activity towards hydrogen evolution reaction (HER) cyclic voltammetry measurements have been done in a 6 M KOH at room temperature and further HER activities have been correlated with the varying Cu concentration in NiCu alloy catalysts.

A district heating system is an eco-friendly power generation facility with high energy efficiency. The boiler water wall tube used in the district heating system is exposed to extremely harsh conditions and unexpected fractures often occur during operation. In this study a corrosion failure analysis of the boiler water wall tube was performed to elucidate the failure mechanisms. The study revealed that overheating by flames was the cause of the failure of the boiler water wall tube. With an increase in temperature in a localized region the microstructure not only changed from ferrite/pearlite to martensite/bainite which made it more susceptible to brittleness but it also developed tensile residual stresses in the water-facing side by generating cavities or microcracks along the grain boundaries inside the tube. High-temperature hydrogen embrittlement combined with stress corrosion cracking initiated many microcracks inside the tube and created an intergranular fracture.

Hydrogen energy has been assessed as a clean and renewable energy source for future energy demand. For harnessing hydrogen energy to its fullest potential storage is a key parameter. It is well known that important hydrogen storage characteristics are operating pressure-temperature of hydrogen hydrogen storage capacity hydrogen absorption-desorption kinetics and heat transfer in the hydride bed. Each application needs specific properties. Every class of hydrogen storage materials has a different set of hydrogenation characteristics. Hence it is required to understand the properties of all hydrogen storage materials. The present review is focused on the state-of– the–art hydrogen storage materials including metal hydrides magnesium-based materials complex hydride systems carbonaceous materials metal organic frameworks perovskites and materials and processes based on artificial intelligence. In each category of materials‘ discovery hydrogen storage mechanism and reaction crystal structure and recent progress have been discussed in detail. Together with the fundamental synthesis process latest techniques of material tailoring like nanostructuring nanoconfinement catalyzing alloying and functionalization have also been discussed. Hydrogen energy research has a promising potential to replace fossil fuels from energy uses especially from automobile sector. In this context efforts initiated worldwide for clean hydrogen production and its use via fuel cell in vehicles is much awaiting steps towards sustainable energy demand.

Methanol is a promising new alternative fuel that emits significantly less carbon dioxide than gasoline. Traditionally methanol was produced by gasifying natural gas and coal. Syn-Gas is created by converting coal and natural gas. After that the Syn-Gas is converted to methanol. Alternative renewable energy-to-methanol conversion processes have been extensively researched in recent years due to the traditional methanol production process’s high carbon footprint. Using an electrolysis cell wind energy can electrolyze water to produce hydrogen. Carbon dioxide is a gas that can be captured from the atmosphere and industrial processes. Carbon dioxide and hydrogen are combusted in a reactor to produce methanol and water; the products are then separated using a distillation column. Although this route is promising it has significant cost and efficiency issues due to the low efficiency of the electrolysis cells and high manufacturing costs. Additionally carbon dioxide capture is an expensive process. Despite these constraints it is still preferable to store excess wind energy in the form of methanol rather than sending it directly to the grid. This process is significantly more carbon-efficient and resource-efficient than conventional processes. Researchers have proposed and/or simulated a variety of wind power methods for methanol processes. This paper discusses these processes. The feasibility of wind energy for methanol production and its future potential is also discussed in this paper.

Increasingly stringent sustainability and decarbonization objectives drive investments in adopting environmentally friendly low and zero-carbon fuels. This study presents a comparative framework of green hydrogen green ammonia and green methanol production and application in a clear context. By harnessing publicly available data sources including from the literature this research delves into the evaluation of green fuels. Building on these insights this study outlines the production process application and strategic pathways to transition into a greener economy by 2050. This envisioned transformation unfolds in three progressive steps: the utilization of green hydrogen green ammonia and green methanol as a sustainable fuel source for transport applications; the integration of these green fuels in industries; and the establishment of mechanisms for achieving the net zero. However this research also reveals the formidable challenges of producing green hydrogen green ammonia and green methanol. These challenges encompass technological intricacies economic barriers societal considerations and far-reaching policy implications necessitating collaborative efforts and innovative solutions to successfully develop and deploy green hydrogen green ammonia and green methanol. The findings unequivocally demonstrate that renewable energy sources play a pivotal role in enabling the production of these green fuels positioning the global transition in the landscape of sustainable energy.

Switching to renewable resources for hydrogen production is essential. Present hydrogen resources such as coal oil and natural gas are depleted and rapidly moving to a dead state and they possess a high carbon footprint. Wastewater is a promising avenue in searching for a renewable hydrogen production resource. Profuse techniques are preferred for hydrogen production. Among them electrolysis is great with wastewater against biological processes by hydrogen purity. Present obstacles behind the process are conversion efficiency intensive energy and cost. This review starts with hydrogen demand wastewater availability and their H2 potential then illustrates the three main types of electrolysis. The main section highlights renewable energy-assisted electrolysis because of its low carbon footprint and zero emission potential for various water electrolysis. High-temperature steam solid oxide electrolysis is a viable option for future scaling due to the versatile adoption of photo electric and thermal energy. A glance at some effective aspirations to large-scale H2 economics such as co-generation biomass utilization Microbial electrolysis waste to low-cost green electrode Carbon dioxide hydrogenation and minerals recovery. This study gives a broader view of facing challenges via versatile future perspectives to eliminate the obstacles above. renewable green H2 along with a low carbon footprint and cost potential to forward the large-scale wastewater electrolysis H2 production in addition to preserving the environment from wastewater and fossil fuel. Geographical and seasonal availability constraints are unavoidable; therefore energy storage and coupling of power sources is essential to attain consistent supply. The lack of regulations and policies supporting the development and adoption of these technologies did not reduce the gap between research and implementation. Life cycle assessment of this electrolysis process is rarely available so we need to focus on the natural effect of this process on the environment.

About 95% of current hydrogen production uses technologies involving primary fossil resources. A minor part is synthesized by low-carbon and close-to-zero-carbon-footprint methods using RESs. The significant expansion of low-carbon hydrogen energy is considered to be a part of the “green transition” policies taking over in technologically leading countries. Projects of hydrogen synthesis from natural gas with carbon capture for subsequent export to European and Asian regions poor in natural resources are considered promising by fossil-rich countries. Quality changes in natural resource use and gas grids will include (1) previously developed scientific groundwork and production facilities for hydrogen energy to stimulate the use of existing natural gas grids for hydrogen energy transport projects; (2) existing infrastructure for gas filling stations in China and Russia to allow the expansion of hydrogen-fuel-cell vehicles (HFCVs) using typical “mini-plant” projects of hydrogen synthesis using methane conversion technology; (3) feasibility testing for different hydrogen synthesis plants at medium and large scales using fossil resources (primarily natural gas) water and atomic energy. The results of this study will help focus on the primary tasks for quality changes in natural resource and gas grid use. Investments made and planned in hydrogen energy are assessed.

This review comprehensively evaluates the integration of solar-powered electrolytic hydrogen (H2) production and captured carbon dioxide (CO2) management for clean fuel production considering all potential steps from H2 production methods to CO2 capture and separation processes. It is expected that the near future will cover CO2-capturing technologies integrated with solar-based H2 production at a commercially viable level and over 5 billion tons of CO2 are expected to be utilized potentially for clean fuel production worldwide in 2050 to achieve carbon-neutral levels. The H2 production out of hydrocarbon-based processes using fossil fuels emits greenhouse gas emissions of 17-38 kg CO2/kg H2. On the other hand . renewable energy based green hydrogen production emits less than 2 kg CO2/kg H2 which makes it really clean and appealing for implementation. In addition capturing CO2 and using for synthesizing alternative fuels with green hydrogen will help generate clean fuels for smart cities. In this regard the most sustainable and promising CO2 capturing method is post-combustion with an adsorption-separation-desorption processes using monoethanolamine adsorbent with high CO2 removal efficiencies from flue gases. Consequently this review article provides perspectives on the potential of integrating CO2-capturing technologies and renewable energy-based H2 production systems for clean production to create sustainable cities and communities.

Currently meeting the global energy demand is largely dependent on fossil fuels such as natural gas coal and oil. Fossil fuels represent a danger to the Earth’s environment and its biological systems. The utilisation of these fuels results in a rise in atmospheric CO2 levels which in turn triggers global warming and adverse changes in the climate. Furthermore these represent finite energy resources that will eventually deplete. There is a pressing need to identify and harness renewable energy sources as a replacement for fossil fuels in the near future. This shift is expected to have a minimal environmental impact and would contribute to ensuring energy security. Hydrogen is considered a highly desirable fuel option with the potential to substitute depleting hydrocarbon resources. This concise review explores diverse methods of renewable hydrogen production with a primary focus on solar wind geothermal and mainly water-splitting techniques such as electrolysis thermolysis photolysis and biomass-related processes. It addresses their limitations and key challenges hampering the global hydrogen economy’s growth including clean value chain creation storage transportation production costs standards and investment risks. The study concludes with research recommendations to enhance production efficiencies and policy suggestions for governments to mitigate investment risks while scaling up the hydrogen economy.

Deregulation in the energy sector has transformed the power systems with significant use of competition innovation and sustainability. This paper outlines a comparative study of renewable energy sources with electric vehicles (RES-EV) integration in a deregulated smart power system to highlight the learning on system efficiency effectiveness viability and the environment. This study depicts the importance of solar and wind energy in reducing carbon emissions and the challenges of integrating RES into present energy grids. It touches on the aspects of advanced energy storage systems demand-side management (DSM) and smart charging technologies for optimizing energy flows and stabilizing grids because of fluctuating demands. Findings were presented to show that based on specific pricing thresholds hybrid renewable energy systems can achieve grid parity and market competitiveness. Novel contributions included an in-depth exploration of the economic and technical feasibility of integrating EVs at the distribution level improvements in power flow control mechanisms and strategies to overcome challenges in decentralized energy systems. These insights will help policymakers and market participants make headway in the adoption of microgrids and smart grids within deregulated energy systems which is a step toward fostering a sustainable and resilient power sector.

Hydrogen is a promising candidate for renewable energy storage and transportation due to its high energy density and zero carbon emissions. Its practical applications face challenges related to safe efficient storage and release systems. This review article investigates advanced nanostructured materials for hydrogen storage including metal acetylide and cyanide complexes BN-doped γ-graphyne nanotubes (γ-GNT) lithium-phosphide double helices and Ni-decorated carbon-based clusters. Density Functional Theory (DFT) based computations are used to analyze binding energies thermodynamic stability and adsorption mechanisms. Ni-decorated C12N12 nanoclusters demonstrate enhanced storage capacities binding up to eight H2 molecules with a favorable N-(μ-Ni)-N configuration. Lithium-phosphide double helices show potential for 9.6 wt% hydrogen storage within a stable semiconducting framework. Functionalization of γ-GNT with OLi2 at boron-doped sites significantly enhances storage potential achieving optimal hydrogen binding energies for practical applications. Additionally metal acetylide and cyanide complexes stabilized by noble gas insertion display thermodynamically favorable hydrogen adsorption. These results highlight the potential of these functionalized nanostructures for achieving high-capacity reversible hydrogen storage. The nanostructures in this study such as γ-graphyne nanotubes (γ-GNT) lithium-phosphide double helices metal acetylide and cyanide complexes and Ni-decorated carbon-based clusters are selected based on their ability to exhibit complementary hydrogen adsorption mechanisms including physisorption and chemisorption. γ-GNT offers high surface area and tunable electronic properties ideal for physisorption enhanced by heteroatom doping. Lithium-phosphide double helices facilitate Kubas-like chemisorption through unsaturated lithium centers. Metal acetylide and cyanide complexes stabilize hydrogen adsorption via charge transfer and conjugated frameworks while Ni-decorated clusters combine polarization-induced physisorption. These materials represent a strategic approach to addressing the challenges of hydrogen storage through diverse and synergistic mechanisms. The review also addresses challenges and outlines future directions to advance hydrogen’s role as a sustainable fuel.

In the twenty-first century global energy consumption is rapidly increasing particularly in emerging nations hastening the depletion of fossil fuel reserves and emphasizing the vital need for sustainable and renewable energy sources. This study aims to analyze hybrid renewable energy systems (HRESs) that use solid waste to generate power focusing on difficulties linked to intermittent renewable sources using a techno-economic framework. Employing the HOMER Pro software prefeasibility analysis is performed to meet the energy needs of an Indian community. System architecture optimization depends on factors like minimizing net present cost (NPC) achieving the lowest cost of energy (COE) and maximizing renewable source utilization. This study evaluates the technical economic and environmental feasibility of a hybrid renewable energy system (HRES) comprising a 400-kW solar photovoltaic (PV) array a 100-kW wind turbine (WT) a 100-kW electrolyzer 918 number of 12V batteries a 200-kW converter a 200-kW reformer and a 15-kg hydrogen tank (H-tank). This optimal configuration has the lowest NPC of $26.8 million and COE of $4.32 per kilowatt-hour and a Renewable Fraction (RF) of 100%. It can provide a dependable power supply and satisfy 94% of the daily onsite load demand which is 1080 kilowatt-hours per day. The required electricity is sourced to load demand entirely from renewable energy at the given location. Additionally the study highlights the benefits of HRES in solid waste management considering technological advancements and regulatory frameworks. Furthermore sensitivity analysis is conducted to measure economic factors that influence HRES accounting for fluctuations in load demand project lifespan diesel fuel costs and interest rates. Installing an HRES custom-made to the local environmental conditions would provide a long-lasting reliable and cost-effective energy source. The results show that the optimal HRES system performs well and is a viable option for sustainable electrification in rural communities.

Alternative fuel opportunities can satisfy energy security and reduce carbon emissions. In this regard the hydrogen fuel is derived from the source of environmental pollutants like sewage and algae wastewater through hydrothermal gasification technique using a KOH catalyst with varied gasification process parameters of duration and temperature of 6–30 min and 500-800 ◦C. The novelty of the work is to identify the optimum gasification process parameter for obtaining the maximum hydrogen yield using a KOH catalyst as an alternative fuel for agricultural engine applications. Influences of gasification processing time and temperature on H2 selectivity Carbon gasification efficiency (CE) Lower heating value (LHV) Hydrogen yield potential (HYP) and gasification efficiency (GE) were studied. Its results showed that the gasifier operated at 800 ◦C for 30 min offering maximum hydrogen yield (26 mol/kg) and gasification efficiency (58 %). The synthesized H2 was an alternative fuel blended with diesel fuel/TiO2 nanoparticles. It was experimentally studied using an internal combustion engine. Influences of H2 on engine perfor mance like brake-specific fuel consumption brake thermal efficiency and emission performances were measured and compared with diesel fuel. The results showed that DH20T has the least (420g/kWh) brake-specific fuel consumption (BSFC) and superior brake thermal efficiency of about 25.2 %. The emission results revealed that the DH20T blend showed the NOX value increased by almost 10.97 % compared to diesel fuel whereas the CO UHC and smoke values reduced by roughly 31.25 28.34 and 42.35 %. The optimum fuel blend (DH20T) result is rec ommended for agricultural engine applications.