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Fusion is very attractive as a potential energy source, but it is taking a long time to develop into a commercial reality. Given the challenges of climate change and the need for dispatchable power as a complement to renewable energy sources that vary on daily and seasonal timescales, there is great enthusiasm internationally to accelerate the commercialization of fusion energy. Forty-five private companies around the globe, with total financing of $7.1 billion, are engaged in the development of fusion energy. In the United States, the White House has put forward a "Bold Decadal Vision for Commercial Fusion Energy," with bipartisan support from Congress. To develop commercial fusion energy, certain goals must be met. A wide variety of approaches are being pursued to meet these goals. [ABSTRACT FROM AUTHOR]

The conversion of biomass to 5-hydroxymethylfurfural (HMF) holds substantial promise as a renewable energy source. Notably, HMF can be transformed into 2,5-bis(hydroxymethyl)furan (BHMF), a crucial reactant in biofuel production, but requires harsh operating conditions, H2, and precious metal catalysts. A recently reported Cannizzaro reaction of HMF to BHMF, characterized by its efficiency, mild conditions, and eco-friendliness, instead employed ionic liquids (ILs) to achieve high yields. In this study, combined quantum mechanical and molecular mechanical (QM/MM) simulations in conjunction with Metropolis Monte Carlo statistical mechanics and free-energy perturbation theory utilized M06-2X/6-31+G(d), PDDG/PM3, and the OPLS-VSIL force field to uncover important solute–solvent interactions present in the HMF to BHMF reaction pathway. The Cannizzaro reaction was examined in water and in five ILs composed of the 1-butyl-3-methylimidazolium [BMIM] cation coupled to hexafluorophosphate, tetrafluoroborate, thiocyanate, chloride, and bromide. Energetic and structural analysis of the rate-determining hydride transfer between HMF and the hydride-donor anion HMFOH− attributed the enhanced reactivity to highly organized solvent interactions featuring (1) hydrogen bonding between the ring protons of [BMIM] and the negatively charged carbonyl oxygen atoms on the transition structure, (2) favorable electrostatic interactions between the IL anions and solute hydroxyl groups, and (3) beneficial π–π stacking interactions between [BMIM] and the two aromatic rings present in HMF and HMFOH−. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenation of biomass-derived chemicals is essential in chemical industry due to the growing demand for sustainable and renewable energy sources. In this study, we present a comprehensive theoretical investigation regarding the hydrogenation of glycolaldehyde to ethylene glycol over a Ru/C catalyst by employing density functional theory and ab initio molecular dynamics simulations. With inclusion of explicit solvation, we have demonstrated that the glycolaldehyde hydrogenation is significantly improved due to the fast proton transfer through the hydrogen bond network. The enhanced activity could be attributed to the participation of the solvent water as the hydrogen source and the highly positively charged state of a Ru cluster in an aqueous phase, which are critical for the activation of aldehyde groups and proton-assisted hydrogenation. Overall, our findings provide valuable insights into glycolaldehyde hydrogenation over Ru/C catalysts in the aqueous phase, highlighting the importance of solvation effects in the biomass conversion. [ABSTRACT FROM AUTHOR]

Professional sport facility sustainability initiatives offer sport organizations an opportunity to demonstrate congruence with societal concern for the environment, an effort that also affects stadia revenue generation. Guided by diffusion of innovations theory, this study harnessed diffusion modeling and logistic regression to determine how quickly renewable energy source adoption is diffusing across 175 professional sport stadia in the United States and Canada and the factors catalyzing early renewable energy source adoption. Results revealed 86 (49%) facilities adopted at least one type of renewable energy source, with solar emerging as the predominant technology adopted (68 total adoptions). Full diffusion for renewable source adoption was predicted for 2061 (p =.0094, q = 0.1404, root mean square error = 3.25, mean absolute error = 2.51), while not all renewable energy sources were predicted to fully diffuse (wind; p =.0117, q = −0.0710, root mean square error =.853, mean absolute error = 0.675). New stadia construction during the time of adoption, facility type, and geographical social systems emerged as significant factors catalyzing adoption in the early majority. [ABSTRACT FROM AUTHOR]

To meet the rising energy needs of the world, the participation of renewable energy sources (RESs) in the power system has been boosted exponentially, primarily due to environmental issues. Islanded operation of power grids as microgrids (MGs) is more common now. Although this has several advantages, the diminished inertia constant has emerged as one of the serious consequences of high penetration level of RESs and islanded operations, which worsens the frequency stability with a higher value of rate of change of frequency (RoCoF). To address this issue, this article proposes a modified form of internal model control (IMC)-based virtual inertia (VI) control, which provides the necessary VI power in low inertia MG, regulates the system's frequency deviation and prevents system instability. The proposed controller has been optimally designed through the grey wolf optimizer (GWO) algorithm with integral time absolute error (ITAE) as the cost function. To demonstrate the effectiveness of the proposed controller, a comparative analysis with existing methods, such as a conventional VI controller, VI emulator based on model-predictive controller, MATLAB-based IMC tuning algorithm for proportional–integral (PI) and proportional–integral–derivative (PID) controller is given under different disturbance and operating conditions. Compared with the conventional VI control method, the frequency deviation has been reduced by almost 80.91% when using the proposed method, for normal operating conditions of system inertia and load damping. Similarly, 79.13% and 73.93% have been reduced in frequency deviation for medium and low operating conditions of system inertia and load damping, respectively. The outcomes from MATLAB simulation show that the given controller offers better frequency responses with improved transient response in comparison with other controllers. [ABSTRACT FROM AUTHOR]

The problem of renewable energy has been gained great interest owing to power demand, environmental issues and increasing oil costs. Among the renewable energy sources, electrocatalytic water hydrolysis in energy conversion is of current interest and alternative for excessive consumption of fossil fuels. The nitrogen doping into robust electrocatalysts gained great interest in energy conversion by regulating the electron density of active sites to enhance the electrocatalysts efficiency. Also, conducting polymers based nanomaterials materialized as efficient electrocatalysts for oxygen and hydrogen evolution reactions owing to specific composition. Herein, the recent progress of nitrogen enriched electrocatalysts and the current challenges with future investigations to support in-depth research efforts in this potential area have been disclosed. • This review focuses an update of efficient N-enriched electrocatalysts with simple, low cost fabrication process. • N-incorporation modulated the electron densities of exposed active sites to enhance the electrocatalytic efficiency. • The electrocatalysts with interfacial heterostructures enhanced the conductivity after N doping. • The recent progress of N-enriched catalysts and correlation of electronic structure with performance have been updated. [ABSTRACT FROM AUTHOR]

The integration of hydrogen technologies with renewable energy sources, such as hydropower, enhances the potential of green hydrogen production while maintaining electricity generation. This paper presents a method for optimally sizing a hydrogen system within a hydropower plant, enabling the cogeneration of green hydrogen and electricity. A decision-support tool based on particle swarm optimisation is developed to balance technical and economic factors, including hydrogen demand, water reserves, electrolyser efficiency, installation costs, and energy-market prices. The approach is applied to a case-study hydropower plant, utilising excess hydropower and photovoltaic electricity to produce hydrogen. The tool successfully optimises multiple objectives, such as income maximisation and hydrogen production targets, demonstrating its potential for integrating hydrogen systems into renewable energy frameworks. This work highlights a viable pathway for advancing the adoption of hydrogen technologies in sustainable energy systems. • Green hydrogen production from excess water energy in a run-of-river hydropower plant is discussed. • The problem of optimally sizing the hydrogen system is exposed. • A decision-support tool based on particle swarm optimisation is developed. • Various objective functions for the optimal sizing of a hydrogen system are presented. • The approach is applied to the case-study hydropower plant. [ABSTRACT FROM AUTHOR]

As an important chemical intermediate, the production of 1,4-butanediol (BDO) mainly depends on the reaction between formaldehyde and acetylene (Reppe method). This process suffers from high CO 2 emissions in the preparation stage of formaldehyde, acetylene, and hydrogen. The green electricity generated by renewable energy is introduced into the system in the form of hydrogen. This provides a renewable source of hydrogen and aids in converting the carbon in raw coal into the desired product, thereby further reducing CO 2 emissions. This study introduces a novel approach for producing 1,4-butanediol by combining coal with off-grid renewable electricity. The proposed reconfiguration process (ALK-CtBDO) involves the implementation of a new calcium carbide production process of coal-coke-electricity grading substitution method (GSM) and a coal-to-methanol process with near-zero carbon emissions, named pulverized coal gasification integrated green hydrogen (PCGwGH-CtM) system and uses green power to electrify utility engineering. The direct CO 2 emissions decreased from 3616.73 kg CO 2 /t BDO in the conventional CtBDO process to 768.07 kg CO 2 /t BDO in the reconfiguration process. The introduction of renewable energy effectively improves the carbon utilization efficiency, increasing it to 68.05% in the ALK-CtBDO process from 34.18% in the CtBDO process. Through the electrification process, the indirect emissions from utilities that use electricity are 1824.57 kg CO 2 /t BDO for the CtBDO process and 378.97 kg CO 2 /t BDO for the ALK-CtBDO process, respectively. The reconfiguration process demonstrates an energy efficiency of 43.28%, representing an improvement from the previous energy efficiency of 40.21% in the conventional process. The process of reconstruction holds a competitive advantage in terms of economic performance when the renewable energy price falls below 0.2 CNY/kWh. This study provides an important reference for the integration of CtBDO with renewable energy, contributing to the promotion of sustainable development in the industry. • Process electrification provides substantial emission reduction benefits. • Over 80% of the electrical energy is utilized to produce H 2 in ALK-CtBDO process. • Direct carbon emissions decreased by 79.23%. • Indirect carbon emissions decreased by 78.23%. • Energy efficiency increased by 7.71% to reach 43.28%. [ABSTRACT FROM AUTHOR]

The Power-to-Ammonia process has been suggested to decarbonize global ammonia production and to enable global energy trade using ammonia as a carbon-free energy carrier. Traditionally, Haber–Bosch plants for ammonia production based on natural gas have been operated near their nominal load and with slow load change rates. Power-to-Ammonia calls for more load-flexible plants to optimally utilize fluctuating renewable energy sources. This work presents a detailed dynamic model of a modified Haber–Bosch plant including feed compression, reaction, separation, and refrigeration. We conduct simulation studies demonstrating load change rates up to 3%/min and safe operation with down to 10% of the nominal feed flow rate. Three strategies are investigated utilizing an increasing number of variables to achieve favorable conditions during part-load operation. Among those, a combination of pressure reduction, reduced flow in the synthesis loop, increased ammonia fraction in the reactor feed, and omitted intercooling between the reactor beds enables the smoothest load transition and best conditions during part-load operation. We further show that a moderate pressure reduction in the synthesis loop can reduce power demand during part-load operation. [Display omitted] • Dynamic simulation of Haber–Bosch plants down to 10% load at ramp rates of 3%/min. • Pressure control for purge-free Haber–Bosch-type synthesis loops was implemented. • Reducing reactor intercooling allows to sustain higher reactor flow at part load. • Increased ammonia fractions in reactor feed are favorable for part-load operation. • Moderate reductions in synthesis loop pressure significantly reduce power demand. [ABSTRACT FROM AUTHOR]

With the growing adoption of renewable energy resources, microgrids (MGs) are increasingly relying on these sources to meet their electrical load demands. To ensure efficient operation, these units must be scheduled in a coordinated manner. This paper introduces a stochastic model for the joint scheduling of renewable and thermal energy units. The study focuses on integrating proton exchange membrane fuel cell-based combined heat and power (PEMFC-CHP) units, wind turbines (WTs), and photovoltaic (PV) systems within the scheduling framework. Additionally, hydrogen storage strategies are incorporated into the PEMFC-CHP operations. The model addresses uncertainties such as wind speed, solar irradiance, and market price fluctuations using a scenario-based approach. The proposed method formulates the scheduling problem as a mixed-integer nonlinear programming (MINP) model, incorporating hydrogen storage strategies. The inherent uncertainties in these parameters further transform the problem into a stochastic MINP. Coordinated scheduling of renewable and thermal units within microgrids not only optimizes resource utilization but also enhances the overall objective function value. These advancements align with current energy policy objectives aimed at improving the efficiency and sustainability of energy systems. To solve the complex scheduling problem, this research employs an Improved Salp Swarm Algorithm (ISSA), which has been tested on a modified 33-bus distribution network. Simulation results indicate that the ISSA achieves over 5% higher revenue compared to other optimization methods. Furthermore, incorporating combined heat and power (CHP) operations increases the total system profit by more than 15%. The algorithm achieved the optimal result in 28 out of 30 attempts. The ISSA algorithm, with a remarkable success rate of 95.28%, demonstrates its effectiveness in minimizing MG operating costs, a critical component of energy policy goals. • A stochastic model is created for coordinated scheduling of renewable energy. • Including uncertainties in the model improves overall profitability. • The role of combined heat and power systems is analyzed in the model. • Hydrogen storage supports fuel cell operation in the proposed framework. • Profit maximization of the microgrid is the main objective. [ABSTRACT FROM AUTHOR]

We investigate the behavior of evaporating droplets in a two-phase rotating detonation engine (RDE) fueled by liquid ethanol, a renewable energy source and hydrogen carrier with relatively high energy density. In the present study, we conduct an Eulerian-Lagrangian simulation to examine the spatial distribution and kinematic motion of ethanol droplets within a rotating detonation flow field over a wide range of equivalence ratios of 0.9–1.6. The droplets are tracked as they are injected into the flow field, with important droplet parameters analyzed comprehensively and correlatively as they evaporate and move downstream. The ethanol droplets are then classified into three main categories: leading-edge droplets near the detonation front, trailing-edge droplets in the post-detonation region that are newly injected, and the remaining droplets that occupy the majority of the fuel refill zone. The droplet distribution patterns are found to shift as the equivalence ratio changes. Specifically, as the equivalence ratio increases, droplet clusters accumulate and gradually move downstream. Under the fuel-rich conditions, particularly at the equivalence ratios between 1.5 and 1.6, excess droplets near the detonation front result in prolonged evaporation, which intensifies and tilts the detonation front, causing localized explosions that disrupt the flow field and droplet injection. • Ethanol as a renewable fuel and hydrogen carrier in rotating detonation engines. • Statistical analysis of droplet behavior in a two-phase rotating detonation flow. • Tracking and classification of droplets upon injection in the flow field. • Correlation of droplet parameters during evaporation after injection. [ABSTRACT FROM AUTHOR]

Replacing traditional gray hydrogen with green hydrogen from renewable energy sources is key to reducing CO 2 emissions. We propose an optimal configuration and production model for Power-to-Hydrogen plants considering the transient states of multiple alkaline electrolyzers. The optimal configuration and dispatch of a real-world hybrid renewable energy source-electrolyzer system was assessed, including multiple electrolyzers, including cold start time, hot standby, and start/stop transition. Various off-grid conditions and wind-solar ratios were compared. The levelized cost of hydrogen for the optimal solutions across different scenarios is lowest at 1.4344 RMB/Nm³ in the PV/Wind-grid-connected scenario. The systems utilize 84.15–94.47% of renewable energy with no more than 66% of the number of electrolyzers required to absorb peak energy. In PV/Wind-grid-connected scenarios, each electrolyzer undergoes an average of 129 startup/shutdown cycles per year, far below the usual requirement. Therefore, technically and economically feasible hydrogen supply is realized from renewable energy for the chemical industry using our optimization strategy. • Optimization of both configuration and dispatch for RES hydrogen production system. • P2H model considering the transient states of multiple alkaline electrolyzers. • Stable hydrogen supply for typical chemical scenarios powered by intermittent RES. • Comparison of LCOH and electrolyzer decay in various scenarios. [ABSTRACT FROM AUTHOR]

The use of reversible solid oxide cells (rSOC) as bi-directional Power-to-Gas (P2G) and Gas-to-Power (G2P) devices in microgrids with renewable energy sources has attracted considerable attention in the last years. The present study analyzes the energy management of a rSOC connected in a microgrid, considering hydrogen prices from the European HYDRIX market and electricity prices and demands from the Spanish electrical grid. The energy management strategy, based on model predictive control, determines the optimal path for transitions between SOE and SOFC according to the market. The strategy relies on a model including experimental rSOC transition times, thermal effects, and safety constraints to avoid undesired mode switching. The study was conducted in a scaled grid-connected system including 10 kW solar and wind renewable generation and a rSOC of 4.2–6 kW (SOFC-SOE). The aim is to assess the impact of different renewable energy sources on the performance of rSOC and on the resulting economic balance. The results show that an energy management strategy considering hydrogen markets can reach higher revenue, with increases of ≈ 4.6% for solar and ≈ 14.1% for wind, compared to existing algorithms based solely on electricity prices. • Predictive control for a rSOC microgrid considering electricity and hydrogen markets. • The solar energy diurnal cycle mainly determines the operation modes of the rSOC. • Wind-dominated microgrids show higher rSOC usage when considering hydrogen markets. • Considering hydrogen markets boosts microgrid revenue by 4.6% (solar) and 14% (wind). [ABSTRACT FROM AUTHOR]

In modern times, energy storage has become recognized as an essential part of the current energy supply chain. The primary rationales for this include the simple fact that it has the potential to improve grid stability, improve the adoption of renewable energy resources, enhance energy system productivity, reducing the use of fossil fuels, and decrease the environmental effect of energy production. While numerous energy storage technologies (ESTs) have been studied and recorded in the literature, their current levels of technological development differ significantly, with relatively few demonstrating sustainability for use on a commercial scale. Although most research articles on energy storage provide a comprehensive overview of these technologies, more information is needed regarding the practical implementation of these innovations for energy storage. To fill this gap, this study thoroughly examines how the different energy storage systems work and is used in real life. This paper provides an overview of energy storage, explains the various methods used to store energy (focusing on alternative energy forms like heat and electricity), and then analyzes numerous energy storage initiatives worldwide. Compressed air energy storage (CAES) is less effective than pumped hydroelectric energy storage (PHES); it is more scalable in some uses and can achieve an efficiency of over 75%. Similarly, molten salts' capacity to store heat wisely for long durations has made them essential for thermal energy storage, especially in concentrating solar power systems. The study concludes by describing obstacles currently hindering the widespread commercial use of energy storage systems. • Energy storage stabilizes grids and promotes renewables. • The energy system becomes more productive while using less fossil fuel. • Study looks several kinds of energy storage systems and global initiatives. • Commercial deployment of energy storage technology faces significant obstacles. [ABSTRACT FROM AUTHOR]

• High-current decoupled water electrolysis by nickel–cobalt based redox mediators. • Ru-doped MoS 2 /NiFe-LDH catalysts grown in situ on 3D ordered gyroid substrate. • The HER and OER potentials are only 1.70 V and 0.27 V at 500 mA cm−2. The conversion of renewable energy sources with relatively large energy fluctuations into hydrogen represents a crucial aspect of energy storage. Nevertheless, the direct water electrolysis process is known to require excessive instantaneous energy consumption and high cost. Two-step alkaline water electrolysis is regarded as a secure and effective method of generating hydrogen from renewable energy sources when compared to direct water electrolysis. Here we propose a two-step alkaline water electrolysis using nickel–cobalt based hydroxide (Ni 0.9 Co 0.1 (OH) 2) as a redox mediator, and a high-performance bifunctional catalyst as gas evolution electrodes (GEE). The substrates for the GEE were prepared using 3D printing and then loaded with in-situ grown Ru-doped MoS 2 /NiFe-LDH hierarchical heterostructure catalysts (MS-NiFe-Ru-3D). The oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) of the MS-NiFe-Ru-3D catalyst can reach up to 500 mA cm−2 at 300 and 250 mV overpotentials, respectively. It can meet the requirement of high catalyst performance for two-step alkaline water electrolysis. The direct water electrolysis using the bifunctional MS-NiFe-Ru-3D catalyst only requires a voltage of 1.85 V at 500 mA cm−2 with minimal attenuation over 300 h. For the two-step alkaline water electrolysis using MS-NiFe-Ru-3D as bifunctional catalysts and Ni 0.9 Co 0.1 (OH) 2 as redox mediator, only 1.70 V and 0.27 V were required for HER and OER at 500 mA cm−2, respectively. This work offers a promising avenue for the efficient conversion of renewable secondary energy sources into hydrogen. [ABSTRACT FROM AUTHOR]

Given the depletion of fossil fuels and the environmental issues they cause, the search for alternative, clean, and renewable energy sources has made significant progress. Among them, the photo-fermentative production of bioenergy stands out as an attractive and environmentally friendly approach. This review comprehensively examines the key biological and technological characteristics and mechanisms involved in the production of biohydrogen and biomethane through photo-fermentation. Specifically, it discusses the use of wastewater or biowaste as feedstocks for photobiological hydrogen production, key factors influencing biohydrogen yields, and various enhancement methods. Building on the insights gained from biohydrogen production, we further explore the processes, methods, and mechanisms for enhancing photo-fermentative biomethane production areas that have not been thoroughly reviewed elsewhere. By linking biohydrogen and biomethane production, this study underscores the complementary roles of these bioenergy sources within a unified photo-fermentative framework. Additionally, it offers a comparative analysis of biohydrogen and biomethane in terms of mechanisms, feedstock utilization, environmental impact, economic viability and efficiency. The aim is to highlight recent advancements in this field, identify challenges and future perspectives, and discuss the potential of photobiological biohydrogen and biomethane as sustainable bioenergy sources. [ABSTRACT FROM AUTHOR]

The CO2 electrochemical reduction reaction (CO2RR) is a promising alternative way to convert CO2 into high value-added fuels and chemicals with renewable electricity as an energy source to solve the current environmental problems. However, the low catalytic efficiency and poor stability of the CO2RR are challenges that need to be addressed. In this review, we summarize the advanced progress in the confinement effect on the CO2RR. In a confined environment, controlled diffusion behaviors of reactants, intermediates and products and charge transfer can effectively facilitate the CO2RR. Meanwhile, the local increase in pH due to the limited diffusion of the electrolyte and in situ-generated OH− can induce slow proton adsorption kinetics, resulting in inhibition of proton-involving reactions, especially the competitive reaction of hydrogen evolution. Besides, confinement structures can effectively stabilize active metal sites against corrosion, fragmentation, dissolution, agglomeration, and over-reduction due to the protection of limited space or/and confined intermediates. Therefore, attempts to illustrate the relationship between confinement architectures and their catalytic performance are necessary, and they are discussed in this review, and the current challenges and potential strategies for future CO2RR research are envisioned. [ABSTRACT FROM AUTHOR]

Rational design of viable routes to develop affordable and efficient oxygen evolution reaction (OER) catalysts is essential for advancing electrochemical water splitting, yet significant challenges remain, particularly in seawater. Here, we propose a ligand defect engineering strategy to modify the electronic structure of NH2-MIL-88B(Fe) using a monodentate ligand (acetic acid, AcOH), inducing ligand vacancies in NH2-MIL-88B(Fe) for oxygen evolution in an alkaline seawater electrolyte, thereby improving the performance of the electrocatalysts. The resulting defective MOFs (denoted as NH2-MIL-88B(Fe)-x) exhibited exceptionally high catalytic activity for OER, requiring low overpotentials of 313 and 329 mV at a current density of 100 mA cm−2 in 1 M KOH and simulated seawater (1 M KOH + 0.5 M NaCl) solutions, respectively. Experimental analyses revealed that the introduction of AcOH can modulate the d-band center of active sites in NH2-MIL-88B(Fe)-x and play a critical role in alleviating chloride ion (Cl−) corrosion, thereby enhancing catalytic stability in seawater. When directly used as an OER catalyst in an alkaline electrolyte, wind and solar power were harnessed to operate the NH2-MIL-88B(Fe)-x ‖‖ Pt/C configuration to drive the electrolytic water reaction. Thus, the ligand defect strategy can be employed to design and prepare high-performance OER electrocatalysts, particularly for generating H2 through water electrolysis powered by renewable energy sources. [ABSTRACT FROM AUTHOR]

Hydrogen plays an important role in decarbonising energy systems due to its potential to be produced from renewable energy sources and the fact that when consumed, it does not lead to greenhouse gas or pollutant emissions. Integrating renewable energy systems with advanced machine learning algorithms offers a transformative approach to overcome the challenges in hydrogen production and improve its sustainability and environmental viability. In this study, green hydrogen production by PEM electrolyzers integrated into photovoltaic panels, wind turbine and hybrid renewable energy systems are predicted by machine learning algorithms such as KNN, XGBoost, Lasso, ANN, LSTM, and RF based on 10 years of meteorological data for various locations in Türkiye. Green hydrogen production amounts are determined for Aydın, Bozcaada, Istanbul, Niğde, and Samsun locations, and the performance of the models is evaluated according to R2, MAE, MSE, and RMSE criteria. The findings reveal that LSTM in Aydın, ANN in Bozcaada, Istanbul, and Niğde, Lasso in Samsun, KNN in Aydın and Bozcaada, Lasso in Samsun, and the RF algorithm in all locations are used for green hydrogen production. It is determined that 557 fuel cell vehicles can be fuelled and 399,911 kg CO₂ emissions can be prevented annually with hydrogen produced using wind energy in Bozcaada. This study highlights the practical implications of integrating machine learning techniques into hydrogen production. Furthermore , the study supports the realisation of the United Nations Sustainable Development Goals (3, 7, 11, and 13) by promoting the transition to green hydrogen and provides valuable insights into the production, storage, and sectoral applications of hydrogen. These findings emphasise the viability of utilising hydrogen technology as a crucial catalyst for a sustainable energy future. • Renewable-powered PEM systems offer a sustainable solution for hydrogen production. • Machine learning boosts precision in green hydrogen production forecasts. • Wind energy reduces 399,911 kg of CO₂ emissions in Bozcaada annually. • 557 fuel cell vehicles can be fuelled by Bozcaada's hydrogen production. [ABSTRACT FROM AUTHOR]

In response to the environmental crisis caused by fossil fuel dependence, this paper explores the potential of hydrogen as a clean alternative energy source. Electrolytic water technology is an important way to produce hydrogen, but it faces challenges such as low energy efficiency, high cost and limited fresh water resources. In order to solve these problems, a high efficiency W–MoS 2 @FeNi 2 S 4 /NF seawater electrolysis catalyst based on non-precious metal materials was firstly developed by using atomic doping techniques and constructing the heterostructure of interface engineering. The catalyst showed excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance in seawater electrolyte of 1.0 M KOH, where the W–MoS 2 @FeNi 2 S 4 /NF electrode had an overpotential of 130 mV and 255 mV at a current density of 10 mA cm−2 and 100 mA cm−2 for HER and OER. In addition, density functional theory (DFT) calculation shows that the FeNi 2 S 4 material plays a key role in catalysis, and the synergistic catalysis of the W–MoS 2 and FeNi 2 S 4 materials makes the W–MoS 2 @FeNi 2 S 4 electrode present a better catalytic performance. This innovation is not only of great significance in promoting the development and application of green energy technologies, but is also expected to develop more efficient and economical electrolytic water catalysts through continued innovation, making an important contribution to achieving carbon neutrality goals and building a sustainable energy system. The W–MoS 2 @FeNi 2 S 4 /NF electrode exhibits excellent hydrogen evolution reaction (HER) (overpotential of 130 mV @10 mA cm−2) and oxygen evolution reaction (OER) (overpotential of 255 mV @100 mA cm−2) activity in seawater electrolytes. [Display omitted] • W–MoS 2 @FeNi 2 S 4 was firstly synthesized through hydrothermal processes. • W doping and MoS 2 enhance the electrocatalytic activity of FeNi 2 S 4. • The W–MoS 2 @FeNi 2 S 4 exhibits superior seawater splitting electrocatalytic activity. [ABSTRACT FROM AUTHOR]

In response to the urgent need for sustainable energy sources, hydrogen production via water splitting stands out for its cost-effectiveness and zero emissions. CuFe 2 O 4 is recognized for its superior photocatalytic properties and efficient visible light absorption. Metal-organic frameworks (MOFs) provide a flexible structure, high surface area, and exceptional stability, enhancing the performance of photocatalysts. In this study, CuFe 2 O 4 is synthesized via microwave-assisted co-precipitation to enhance optoelectronic properties and charge separation efficiency. Meanwhile, Ni-MOF is synthesized using a hydrothermal approach to offer precise control over morphology, crystallinity, and stability. A novel CuFe 2 O 4 @Ni-MOF nanomagnetic photocatalyst is prepared through ultrasonication, facilitating enhanced dispersion and intimate contact between the materials. Comprehensive characterization using techniques such as XRD, XPS, BET, SEM-EDX, UV, PL, and VSM confirms the structural, thermal, and textural properties of the photocatalyst. This synergetic effect of CuFe 2 O 4 @Ni-MOF leads to improved charge transfer efficiency and photocatalytic activity, as evidenced by hydrogen production rates of 250, 570, and 305 mmolh−1g−1 for CuFe 2 O 4 @Ni-MOF ratios of 10%, 15%, and 20%, respectively. Furthermore, the magnetic property of CuFe 2 O 4 @ Ni-MOF is leveraged to enhance catalytic activity, as demonstrated by a significant drop in activity when transitioning from magnetic to mechanical stirring. Notably, the 15%CuFe 2 O 4 @Ni-MOF catalyst exhibits superior photocatalytic activity over eight cycles, achieving a hydrogen generation rate exceeding 475 mmolh−1g−1 after the eighth run. This study demonstrates the synergistic effect of combining CuFe 2 O 4 and MOF-based systems, offering a promising pathway for sustainable and efficient hydrogen generation, thus addressing pressing energy challenges. [Display omitted] • Ultra-sonication boosts dispersion and material interaction in CuFe 2 O 4 @Ni-MOF synthesis. • Synergy of CuFe 2 O 4 and Ni-MOF increases charge transfer and photocatalytic efficiency. • Magnetic nature of CuFe 2 O 4 @Ni-MOF enhances catalytic activity. • 15%CuFe 2 O 4 @Ni-MOF shows high activity over eight cycles, H 2 producing 475 mmolh−1g−1. [ABSTRACT FROM AUTHOR]

This study offers a comprehensive analysis of the feasibility of green hydrogen economies in Western and Southern African regions, focusing on the ECOWAS and SADC countries. Utilizing a novel approach based on composite indicators, the research evaluates the potential, readiness, and overall feasibility of green hydrogen production and export across these regions. The study incorporates various factors, including the technical potential of renewable energy sources, water resource availability, energy security, and existing infrastructure for transport and export. Country-specific analyses reveal unique insights into the diverse potential of nations like South Africa, Lesotho, Ghana, Nigeria, Angola, and Namibia, each with its unique strengths and challenges in the context of green hydrogen. The research findings underscore the complexity of developing green hydrogen economies, highlighting the need for nuanced, region-specific approaches that consider technical, socio-economic, geopolitical, and environmental factors. The paper concludes that cooperation and integration between countries in the regions may be crucial for the success of a future green hydrogen economy. • Composite indicators (CI) are utilized for green hydrogen feasibility assessment. • Developed CI incorporate energy framework and SDG policies as well. • Uncorrelated export and hydrogen production suggests common regional strategies. • Hydrogen economy feasibility varies widely across West and Southern Africa. [ABSTRACT FROM AUTHOR]

The ongoing discourse on the transition to a hydrogen-based economy and the lessons learned from visions such as the Desertec concept emphasise the necessity for a nuanced approach to the development of metrics to assess a country's hydrogen readiness. In addition to economic criteria such as investment incentives, factors including law and order, governance performance, geography, infrastructure, and renewable energy production potential significantly impact a location's attractiveness. To transparently evaluate sites using multiple criteria defined in the PESTEL framework, this article aims to analyse, quantify, and compare the development of a sustainable hydrogen economy in 18 Middle East and North African states. The index-based assessment integrates criteria across three dimensions, offering a comprehensive perspective on regional challenges and opportunities, striking for policymakers and investors. The results show that the highest-ranked countries belong to the Gulf Cooperation Council, followed by North African countries. • Strategic hydrogen investments need comprehensive and holistic evaluations. • PESTEL analysis is useful for identifying hydrogen economy drivers and barriers. • H2EX assesses hydrogen potential using 12 indicators across three dimensions. • Saudi Arabia and the UAE lead MENA in hydrogen economy potential. • Streamlined index criteria improve usability and clarity (Occham's razor). [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effects of renewable energy consumption along with some other regressors namely income by gross domestic product (GDP) per capita, foreign remittances, inflation rate, growth in population on human development in eight Asian countries (Pakistan, Malaysia, Sri Lanka, India, China, Indonesia, Bangladesh, and Japan) from 1995 to 2018. Based on the nature of panel balanced data, we employed the fully modified ordinary least squares and fixed-effects estimators for the empirical investigation. The empirical estimates exhibit that renewable energy usage, foreign remittances and real per capita income have substantial positive impacts on human development. In contrast, inflation rate and growth in population have negative link with human development in the sample countries. Empirical estimates reveal that renewable energy usage positively contribute enhancing human development. These findings expose that the availability and accessibility of renewable energy will not only improve human development rather will also help in accomplishing sustainable development goals. Empirical findings suggest that the management authorities need to allocate more budget in investment in renewable energy schemes and also create environment which facilitate by providing incentives to the private sector also for renewable energy production in the Asian countries. [ABSTRACT FROM AUTHOR]

A chance-constrained energy dispatch model based on the distributed stochastic model predictive control (DSMPC) approach for an islanded multi-microgrid system is proposed. An ambiguity set considering the inherent uncertainties of renewable energy sources (RESs) is constructed without requiring the full distribution knowledge of the uncertainties. The power balance chance constraint is reformulated within the framework of the distributionally robust optimization (DRO) approach. With the exchange of information and energy flow, each microgrid can achieve its local supply-demand balance. Furthermore, the closed-loop stability and recursive feasibility of the proposed algorithm are proved. The comparative results with other DSMPC methods show that a trade-off between robustness and economy can be achieved. [ABSTRACT FROM AUTHOR]

This paper presents the dendrite neural network (DNN) scheme for predicting two challenging parameters, namely the output power and efficiency of the solar free-piston Stirling engine (FPSE). This paper utilizes vital characteristics to predict the output power and efficiency accurately. MSE and regression analysis are employed to investigate the reliability of the proposed DNN structure. As a result, not only was the MSE close to zero, but the regression outcomes were also very close to 1, which confirmed the reliability of the DNN. In the next step, several experimental case studies are used to study the effectiveness of the proposed DNN more thoroughly. Therefore, a maximum error of 5% was observed, confirming good agreement between the empirical data and the predictions made by the DNN. Lastly, through the simulation and experimental investigations, it can be concluded that the method is reliable and can be used for other types of FPSEs. [ABSTRACT FROM AUTHOR]

Due to the rapid advances in renewable energy technologies, the growing integration of renewable sources has led to reduced resources for Fast Frequency Response (FFR) in power systems, challenging frequency stability. Photovoltaic (PV) plants are a key component of clean energy. To enable PV plants to contribute to FFR, a hybrid energy system is the most favorable candidate, and its power sharing algorithm significantly influences the FFR capability of PV plants. In this study, a model is established for a Virtual Synchronous Generator Hybrid Energy Storage System (VSG HESS). In addition, the mechanism by which PV plants participate in fast frequency regulation is analyzed. Subsequently, a novel multi-dimensional time filtering algorithm is proposed to overcome the problems associated with the short frequency sampling periods and insufficient measurement data in PV plants. Specifically, the techniques of Multi-Delay embedding Transform (MDT), Tucker decomposition, and Multivariate Variational Modal Decomposition (MVMD) are integrated into a unified framework for improved frequency resolution prior to frequency division. Finally, the effectiveness of the proposed method is validated through online simulations performed on a VSG-controlled PV storage microgrid platform. Simulation results reveal that the proposed method is able to outperform conventional filtering algorithms in terms of frequency division accuracy and calculation speed. [ABSTRACT FROM AUTHOR]

A sharp increase in energy prices since 2021 has had a significant impact on the European Union (EU) energy market turning the energy poverty issue into an important concern. Around 42 million EU citizens or 9.3 % of the total population in the Union faced an inability to adequately heat their homes in 2022. It is a clear call for policymakers to seriously address the energy poverty aspects eliminating the negative socio-economic impact. The research aims to analyse the energy poverty concept, its main indicators and affecting factors, identifying the possible solutions for reducing energy poverty, and paying particular attention to vulnerable users. The qualitative methods were used, i.e., the authors conducted a literature review and scrutinized scientific publications, reports and legal acts. As a result of the research, the authors have characterised the energy poverty situation in different countries, identified the main areas for solving the energy poverty challenge, as well as shared experiences of different countries on the solutions taken. The authors conclude that energy poverty has a particular impact on low-income households, children, disabled people, seniors and single mothers, who may have relatively higher energy consumption and limited resources available. In this regard, countries can benefit from such measures as setting a clear definition of energy poverty and its measurable indicators, identification of supported households, on-the-spot consultations and audits, attracting local governments, and non-governmental organisations, as well as improvement of support instruments of renewable energy sources. [ABSTRACT FROM AUTHOR]

Auctions have become the most important policy instrument for promoting renewable energy (RE). This article offers a conceptual and methodological framework to grasp the variety of national RE auctions' governance arrangements. It presents indices to systematically measure and compare key dimensions of RE auctions and electricity governance: scope of regulation, private operators' influence, coordination, and the concentration of authority. The framework's usefulness is demonstrated via its application to three contrasted cases – the United Kingdom, Mexico, and Morocco, showing the disruption in electricity governance patterns induced by RE auctions and the relevance of the multidimensional approach to understand policy outcomes. [ABSTRACT FROM AUTHOR]

• Treatment of anaerobic digestion digestate has significant climate change impact. • Detailed assessment of the biotreatment of liquid digestate is recommended. • N 2 O emissions from the biotreatment of liquid digestate are substantial. • The impact of the preferred digestate biotreatment changes with the energy system. • The biowaste system is a burden to climate change in a renewable future. The liquid fraction of digestate (LFD) from anaerobic digestion of food waste contains high nitrogen concentrations, and in some countries, the LFD is treated as wastewater. We modelled alternative LFD treatments, including pretreatment with the partial nitritation Anammox (PNA) process. The PNA effluent is discharged to the sewers to undergo further treatment by conventional nitrification and (post- or pre-) denitrification. Life-cycle inventories were developed for the LFD treatment alternatives, including N 2 O emissions and electricity consumption estimates. The climate change (CC) impact was estimated using life cycle assessment in three different energy systems ranging from fossil-based to fully renewable. In the fossil energy system, pretreatment with PNA was attractive, while in the more renewable energy systems, the PNA process did not improve the CC account due to high N 2 O emissions. Pre-denitrification is the most attractive LFD treatment technology in a fully renewable energy system. Linking the LFD treatment to the anaerobic digestion of food waste showed that LFD treatment is a significant contributor to the overall CC account. As we move towards less fossil-based electricity, the anaerobic digestion of food waste constitutes a CC load of 350–450 kg CO 2 -eq/tonne biowaste, of which up to a third can be attributed to the LFD treatment. The N 2 O emissions are the main contributor, constituting up to 50 % in a fossil-based energy system and even higher in a renewable energy system. We conclude that the LFD treatment must be addressed in assessing anaerobic digestion when the LFD is discharged to the sewer. Our study also points to the need to find alternative ways of managing the LFD. [ABSTRACT FROM AUTHOR]

• Electrification should go together with de-fossilization of the grid electricity. • Pyrolysis is the dominant technology for the electrified treatment of plastic waste. • An electrified value-chain for plastics circularity comprises 4 major steps. In contemporary times, global plastic waste production has doubled in comparison to two decades ago, with only 9% effectively recycled. The polymer industry is undergoing a transition to address the disparity between plastic production and end-of-life waste management. Chemical recycling offers a solution by converting plastic waste into its constituent building blocks, or monomers, which can be utilized in the production of new, high-quality plastics. This concise review provides an overview of conventional chemical recycling technologies employing heated reactors, before delving into ongoing efforts towards electrifying the chemical recycling process. A conceptual framework for a fully electrified value chain aimed at achieving plastics circularity is outlined and analyzed. Additionally, attention is given to the challenges posed by industry inertia towards adopting electrified technologies, as well as performance issues stemming from the intermittent nature of renewable energy sources and the availability of long-duration renewable electricity storage options. [ABSTRACT FROM AUTHOR]