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Energy decision-makers have considered solutions to meet the demand for affordable and highly reliable energy due to population growth and technological advancement. One of these possibilities is the utilization of several energy carriers in one system as an energy hub. Instead of optimizing a single energy carrier, the energy hub optimizes a system with many energy carriers, including electricity, natural gas, and local heat, by use of its converters and storages. In this paper, a novel and new general framework is proposed to evaluate and compare both series and parallel connections of n hub to analyze cost and reliability aspects by considering coupling matrices. In order to compare the outcomes of the connections of several comparable hubs in both series and parallel modes, new indices are proposed and evaluated from the aspect of evaluating the amount of energy not supplied and the amount of energy input to each hub. Additionally, simulations are run for a variety of scenarios in order to better assess the proposed model and investigate each type of connection by evaluating the proposed performance indices. The results show that in all the examined scenarios, the total cost of the energy carriers in the series mode (link in the output) is lower than in the parallel mode (link in the input). [ABSTRACT FROM AUTHOR]

In this paper, a new hybrid multiobjective algorithm, namely, the modified bald eagle search Algorithm (MBES), integrated with the grasshopper optimization algorithm, is proposed to solve the unit commitment (UC) problem. We consider a standard 10-unit power system with two wind farms, two photovoltaic farms, and flexible loads for optimization purposes. The UC problem is tackled under uncertainties related to demand and renewable generation capacities. To account for these uncertainties, probability density functions (PDFs) are assigned to the sources of uncertainty, and Monte Carlo simulation (MCS) is employed to select several scenarios with specific probability coefficients. Additionally, two innovative objective functions based on operation cost and emissions are introduced, with each scenario weighted based on its occurrence probability. To assess the performance of the proposed MOGOA-MBES algorithm, simulations are conducted across three scenarios with varying conditions, and the results are compared against those obtained from several multiobjective algorithms. Our findings, supported by optimization results and the S-metric index, demonstrate that the proposed MOGOA-MBES algorithm outperforms other algorithms in terms of reducing operation cost and emissions. Furthermore, the simulation results reveal that uncertainties lead to an increase in cost and emissions, whereas the inclusion of flexible loads and their participation in the UC program can effectively mitigate cost and emission levels. [ABSTRACT FROM AUTHOR]

Summary: This paper presents an optimal parameter identification strategy of the lithium‐ion (Li‐ion) battery model applying a recent metaheuristic artificial ecosystem‐based optimization (AEO) algorithm, which proves its ability in terms of both convergence speed and complexity. The key idea is to update the battery model parameters using the optimizer outputs. In the current paper, the battery model is based on the Shepherd model. To demonstrate the superiority of the suggested method of identification, the test results are compared in terms of efficiency, convergence speed, and accuracy of identification with those obtained by the salp swarm algorithm, the political optimizer, the equilibrium optimizer, and particle swarm optimization. Through the optimization procedure, the undetermined parameters of the battery model are employed as decision variables, but the root‐mean‐square error between estimated data and battery data is assigned to be an objective function must be minimal. The results showed the superior identification ability of the AEO compared to the other optimizers. This optimizer achieved 99.9% identification efficiency, which makes it an ideal solution for battery identification. Besides its identification efficiency, the AEO is much faster than the other optimizers, as the results show. [ABSTRACT FROM AUTHOR]

Summary: This paper presents the design and implementation of a control for an electric vehicle charger to provide vehicle to grid (V2G) services while reducing the current total harmonic distortion (THD). The control is composed of two current loops. The main one controls the active and reactive powers in a decoupled way, and the second one, focuses on the reduction of the fifth order harmonic component. After explaining the mathematical modelling, the methodology and the experimental setup, the results of the experimental validation are shown. Several experiments were conducted on a scale‐based charger connected to a 400 V grid to observe the performance of the proposed control. Results have shown that the developed control enhances the power quality by reducing the fifth harmonic component by 76.34%, and hence, the current THD from 6.06% to 2.82% and that can successfully provide voltage and frequency regulation without adding extra weight or volume. The proposed strategy can also be extrapolated to other harmonic orders; therefore, it is suitable for grids with high components of certain harmonics. Novelty Statement: The paper presents the design and implementation of a control strategy for vehicle chargers aimed at reducing the current THD produced by a specific voltage harmonic of the grid. The control strategy is simple to implement, robust, and does not require additional elements, and thus, not extra weight or volume is added. Thanks to the double‐loop, it allows independent control of the active and reactive power and the minimization of the nth harmonic from the current. For the experimental test, the proposed control strategy has been used to develop a Fifth Harmonic Controller (FHC) to suppress the fifth harmonic from the current. [ABSTRACT FROM AUTHOR]

Summary: The popularity of the electric vehicles has been growing due to the concern of increase in environmental pollution. In order to overcome the environmental issues, electric vehicles have been introduced all over the globe. As the use and number of electric vehicles is growing, there is a great demand to identify the sustainable solutions for intelligent charging station dedicated to electric vehicles. The objective of this paper is to explore the possibilities for intelligent charging station using 5G services. This paper is a state‐of‐the‐art concept to identify the current challenges and issues of intelligent charging station. It should be noted that in the future, the use of the smart charging station will dramatically improve the efficiency of current charging stations. It is identified based on several existing techniques that the biggest challenges are the connectivity between the vehicles and among different charging stations. This manuscript could be useful for researchers working on intelligent charging station worldwide and on their integration with the recent communication technologies like 5G. The features of intelligent charging stations combined with the fifth‐generation network represent a new path for humanity and introduce a safer and more advanced environment. From data privacy to human safety, the network provides enough resources to rise driving quality, time and fuel economy and human lives saving. The results of this research can be well applied in the industry or in the field of academic research. [ABSTRACT FROM AUTHOR]

Summary Flexibilities offered by gas‐fired power plants have strongly increased their usage in power systems. Increasing the penetration rate of gas‐fired power plants has made it necessary to coordinate gas network expansion planning with electricity network expansion planning. In this paper, a decentralized model for expansion of gas and electricity networks is introduced that coordinates investment in these networks while taking into account their privacy. Alternating direction method of multipliers is used to decompose the centralized gas and electricity expansion problem into two separate expansion problems. The proposed method aims to minimize the investment and operation cost of interconnected gas and electricity networks during the planning period. The resultant problems are mixed‐integer nonlinear programs, which are then linearized and transformed into mixed‐integer linear programming models to facilitate the optimality conditions. Distributed optimization provides a cyber‐physical system in which gas and electricity networks are managed separately while a coordination link is provided through the cloud computing layer. However, coordinated operation through a cloud layer keeps the control‐loop subject to cyber‐attacks. In this paper, the standard form of the proposed decentralized model is modified to secure it against cyber‐attacks. Finally, the effectiveness and applicability of the proposed method are tested and verified over a real case study that has a high penetration level of gas consuming generation units. The proposed cyber secure model not only converges faster than a standard model (ie, computationally more efficient than conventional methods) but also keeps optimality of found solution in a secure fashion. The satisfactory performance of the proposed model is also demonstrated against centralized, leader‐follower, and independent expansion planning models. [ABSTRACT FROM AUTHOR]

Summary: Lithium‐ion batteries (LIBs) are widely used in electric vehicles due to its high energy density and low pollution. As the key monitoring parameters of battery management system (BMS), accurate estimation of the state of charge (SOC) and state of health (SOH) can promote the utilization rate of battery, which is of great significance to ensure the safe use of LIBs. In this paper, a novel dual Kalman filter method is proposed to achieve simultaneous SOC and SOH estimation. This paper improves the estimation accuracy of SOC and SOH from the following four aspects. Firstly, the widely used equivalent circuit model is established as the battery model in this paper, and the forgetting factor recursive least squares (FFRLS) method is applied to identify the model parameters. Secondly, two kinds of single‐variable battery states are established to analyze the influence of OCV‐SOC curve and battery capacity on SOC estimation. Based on this, an error model is proposed combined with Kalman filter to achieve better estimation results of SOC and SOH. Besides, to promote the accuracy of SOC estimation, based on the error innovation sequence (EIS) and residual innovation sequence (RIS), the improved dual adaptive extended Kalman filter (IDAEKF) algorithm based on dynamic window is proposed. Finally, the superiority of the proposed model is verified under different cycles. Experimental results show that the estimation error of SOC and SOH is controlled within 1%. [ABSTRACT FROM AUTHOR]

Summary: The optimal sizing of a hybrid energy system may be a difficult undertaking problem because of the huge number of structure settings and the irregular nature of solar radiation and wind power sources. This issue has a place with the classification of combinatorial enhancement, and its solution dependent on the classical technique may be a waste of time. In the present paper, the generation cost of isolated PV‐wind by bird system is minimized by increasing the capacity factor of the system by adjusting both of PV‐tilt angle and wind turbine hub height such that the average generated power is as near as possible to the generation peak. By considering the PV‐tilt angle and the turbine hub height, the diversity between the two generation patterns increases resulting in lower cost. The objective of the present paper is to find the optimal design of the PV‐wind hybrid system based on minimum cost criterion using a genetic algorithm. Also, it studies the effect of considering the PV‐tilt angle and wind turbine hub height as design parameters for different diversity levels of wind speed and sun irradiance patterns. [ABSTRACT FROM AUTHOR]

Summary: The Extensive Damage Mitigation Guideline (EDMG), which was developed by the U.S. Nuclear Energy Institute (NEI) owing to the motivation of 911 terrorist attacks and not allowed to spread before the Fukushima nuclear accident, was publicly available after Fukushima nuclear accident and paid attention to worldwide. Many countries have adopted the U.S. EDMG methodology and developed their strategies (some are not called EDMG but have similar functions), planning to introduce it into the emergency plans of their domestic nuclear power plants (NPPs). Based on the defense‐in‐depth (DID) concept of nuclear safety, the experience of the Fukushima nuclear accident, and the state‐of‐the‐art of EDMGs research, this paper will give a comprehensive review of EDMG. To illustrate the reason for the introduction of EDMG into the traditional NPP procedures/guidelines, the review work started from the perspective of DID in nuclear safety and the reason for the Fukushima nuclear accident from the viewpoint of DID, which showed the weaknesses of DID implementation strategy ‐ underestimation of the damage during a beyond‐design‐basis external event (BDBEE). EDMG is crucial complementary for the old framework of procedures/guidelines to enhance the concept of DID. The research progress of EDMG in different countries has been reviewed and a rough comparison has been made among them according to the present state‐of‐the‐art from literature. The methodology of EDMG is summarized as follows: (a) Loss of Large Area (LOLA) ‐ the originally designed scenario for EDMG; (b) elements of EDMG ‐ the summarized contents for EDMG implementation; (c) classification of EDMG ‐ initial response EDMGs and Technical Support Center (TSC) response EDMGs; (d) implementation of EDMG‐introduction of three phases of EDMG implementation step by step. Furthermore, three typical methods to integrate EDMG into the traditional procedures/guidelines are reviewed. Finally, this paper gives some concluding remarks for EDMG‐related critical issues and recommended future work, which may be challenges for the development and application of EDMG and useful for the related researchers. Novelty Statement: The studies of the extensive damage mitigation guideline (EDMG), its methodology, and the progress in different countries have been reviewed.Three typical methods to integrate EDMG into the traditional procedures/guidelines are summarized and reviewed.Concluding remarks for EDMG‐related critical issues and recommended future work are summarized. [ABSTRACT FROM AUTHOR]

Summary: Fluoride‐salt‐cooled solid‐fuel fast reactor (LSFR) with thorium‐based fuel could complete a self‐sustaining core that fulfills long‐term energy demands. This paper further investigated the LSFR core sustainability of breeding thorium and the spent fuel characteristics for closed fuel cycle. Two fuel recycle strategies were proposed in this paper, including U recycling and U/Pu/MA recycling, to evaluate the physical effects caused by these recycling some highly radiotoxic and heat producing minor actinides. Based on the two fuel management strategies, the sustainability of breeding thorium and the spent fuel characteristics from the 0th cycle core to the 8th cycle core were assessed, including radioactivity, radiotoxicity, and decay heat. It was found that both recycle strategies accomplished good breeding performance and reduced the 233U fuel inventory, implying that recycling nuclides could partially replace 233U. The U/Pu/MA recycling scheme possessed slightly better advantages in lower 233U loading and breeding performance, but this scheme accumulated more transuranium elements with cycle burnup because the LSFR core could not transmute MA for its relatively soft fast energy spectrum. In spite of this, the level of radioactivity, radiotoxicity, and decay heat for the discharge fuel in the 8th cycle core was either lower than or comparable to that of traditional PWR. It is worthwhile mentioning that between 1000 and 100 000 years the radioactivity, radiotoxicity, and decay heat production tend to grow again, which might require sophisticated storage design for LSFR core with thorium‐based fuel in the future. [ABSTRACT FROM AUTHOR]

Summary: Lead‐based fast reactor is one of the most promising fourth‐generation nuclear energy systems. Fuel assembly design is a key technology for the research and development of lead‐based fast reactor. The current status of typical lead‐based reactors and fuel assembly design schemes in the world are reviewed in this paper, and also the key technical parameters and design features of fuel assembly are summarized, with the advantages and disadvantages discussed. A hexagonal fuel assembly that can achieve both "passive" and "active" axial positioning by the gravity of ballast unit and mechanical locking device proposed by the nuclear fuel assembly research group of China initiative Accelerator Driven System project at Institute of Modern Physics has been emphatically introduced. It is expected that this paper can provide certain supporting data and reference solutions for the further design and development of fuel assembly for lead‐based reactor. [ABSTRACT FROM AUTHOR]

Summary: Since 1960s, many countries led by the United States and Russia have done a lot of research on space nuclear reactor power. Moderator is an important functional component in a nuclear reactor operating with a thermal neutron spectrum. This paper reviews the moderation principle, main existing problems, research status as well as main challenges ahead and possible solutions of moderator materials in space nuclear reactor. Aiming at the problems of hydrogen cracking, the low utilization rate of nuclear fuel and hydrogen loss of moderator materials, the assumption of using high entropy alloy hydride as a moderator material is put forward. Moreover, this paper also points out the metal elements suitable for nuclear reactor, while discussing the advantages and disadvantages of several typical elements, hoping to provide a reference for the selection and fabrication of moderator materials. Highlights: Sketch the moderating mechanism and the moderator selection principle.Summarize the problems and solutions in the preparation of metal hydride.Summarize the application status of zirconium hydride and yttrium hydride moderator materials.Predict the future development trend and feasible methods of moderator materials. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a systematic review of the micro‐modular thorium‐fueled high temperature reactors (HTR) loaded with duplex fuel pellet design. Specifically, each unique criterion of the design is discussed separately in an attempt to understand the combined advantages of the proposed reactor. Micro modular HTRs have great potential as a source of electricity or industrial heat in the future. The use of thorium not only improves its economic performance and safety, but also prolongs its operation. Nevertheless, the traditional seed‐and‐blanket configuration would not be able to maximize the thorium fuel burnup. As such, a new tristructural‐isotopic (TRISO) fuel based on duplex pellet designs were proposed instead. It should be noted that these duplex pellets were not practical for pressurized water reactor (PWR) technology due to its uneven power distribution which possibly leads to a very high local pellet temperature. However, this unorthodox inherent characteristics of the duplex pellets may actually suit the HTR burnup profile better due to its substantially higher thermal margin ‐ thus possibly enabling a relatively long operation of the HTR. The paper shall thereby provide a reasonably sound justification for the detailed technical investigations of the proposed reactor design. [ABSTRACT FROM AUTHOR]

Summary: The super‐critical water‐cooled reactor (SCWR) is one of six types of Gen‐IV reactors. Based on the current mature pressurized water reactor technology, it has several advantages, including high conversion ratio, high breeding of nuclear fuel, high thermal efficiency, and a simplified system. However, due to the combination of water coolant and fast neutron spectrum, there is a need to address safety problems caused by the positive void coefficient. The purpose of this paper is to give a study on physical characteristics for the reactor core. Herein, the core modeling of an SCWR with a single‐pass flow is that seed assemblies and blanket assemblies are arranged in a tornado manner, in which MCNP and SERPENT are used for critical calculation. The assembly design is discussed from the aspects of the thickness of the solid moderator layer and cladding material. Based on the optimized assembly design, UO2, PuO2‐ThO2, and PuO2‐UO2 are selected for the sensitivity analysis of fuel composition. In addition, sensitivity analysis for axial coolant density distribution, water‐to‐fuel volume ratio, reflector thickness and fuel arrangement are carried out. Several fundamental system characteristics are discussed in this paper, including keff, void coefficient, Doppler coefficient, neutron spectrum, power distribution, one‐cycle burnup and conversion ratio. The results help in understanding the design of the SCWR better and provide fundamental research data for further study. [ABSTRACT FROM AUTHOR]

Summary: The development of deep space exploration requires space nuclear reactor with higher power and better endurance. In order to meet the increasing high power requirements for space applications, an Open‐grid MEgawatt Gas‐cooled spAce nuclear reactor (OMEGA) is proposed in the paper, which is featured with low specific mass and high energy conversion coefficients. A set of models, including neutron kinetics model, reactivity feedback model and heat transfer model are established. Besides, the space nuclear system analysis code (System Analysis code of MEgawatt gas‐cooled space Reactor [SAMER]) is developed by finite volume method and staggered grid technique for the preliminary safety analysis of the OMEGA conceptual design. Furthermore, the calculation results provided by the SAMER code agree well with the computational fluid dynamics simulation, validating the reliability of the code. Moreover, the transient thermal‐hydraulic responses of the OMEGA under the unprotected reactivity insertion accident (URIA) and the unprotected loss of partial coolant flow accident (LOFA) are obtained and analyzed. The maximum fuel temperature after the URIA has a margin of 262 K from the fuel temperature limit value. The total power after the LOFA is about 68.7% of the rated power, meanwhile, the fuel radial temperature distribution tends to be more uniform with the fuel average temperature unchanged. It can be found that the OMEGA design shows satisfactory safety characteristic and reliability under the URIA and the LOFA scenarios. This paper is the stage summary of the conceptual design work of the OMEGA, and it may provide useful reference for megawatt space nuclear system design and thermal‐hydraulic analysis. [ABSTRACT FROM AUTHOR]

Summary: As an energy storage material, microencapsulated phase change materials (MPCMs) have become a research hotspot in recent years due to their unique thermophysical properties. However, this material usually has limitations in terms of its performance, such as low encapsulation efficiency, leakage during phase change, poor cycle stability, and high degree of supercooling. To solve these problems, nanoparticle as‐modified material to improve the performance of MPCMs has attracted the attention of both domestic and overseas scholars. This paper aims to review the research progress of MPCMs modified by nanoparticle from three aspects: preparation, performance, and application. In this paper, the preparation method and principle of nanoparticles used for the modification of MPCMs are first introduced. Then, based on different properties (mechanical properties, thermal conductivity, thermal stability, and supercooling), the research works of nanoparticle‐modified MPCMs in recent years are reviewed. Finally, the practical applications of nanocomposite MPCM in the field of slurry, building, asphalt pavement, and battery thermal management are reported. [ABSTRACT FROM AUTHOR]

Summary: In order to solve the problem that the unsatisfactory accuracy of SOH estimation method, which seeks the relationship between battery life and external characteristics through experiments, is restricted by battery consistency in a large number of battery applications, this paper proposes an SOH estimation framework which can automatically correct the errors caused by the battery consistency problem online. The SOH framework realizes the automatic online fast correction of SOH estimation error through the designed closed‐loop feedback framework. Another advantage of this framework is that it can achieve accurate estimation for the batteries state of health (SOH) during the irregular charging and discharging process of electric vehicles. And in this framework, a new equivalent circuit based on the autoregressive (AR) model is proposed to reduce the complexity of the battery method while ensuring the accuracy of the estimation, which has better robustness in practical applications. Finally, it is proved that the online estimation of lithium‐ion batteries SOH during discharge proposed in this paper has better practicability and higher estimation accuracy by comparing with the traditional SOH method of external feature relationship. [ABSTRACT FROM AUTHOR]

Summary: A negative electron affinity photocathode can be obtained by adsorbing Cs on the emission layer surface of photocathode, which greatly improves the number of electrons escaped and the quantum efficiency. Based on first principles, this paper studies the structural and electronic properties of Cs‐adsorbed GaN monolayer and bilayer. The results reveal that the Cs‐adsorbed GaN monolayer is the most stable when Cs atom is adsorbed at TGa site. There is a significant charge transfer between Cs atom and GaN monolayer, and the difference in electronegativity makes electrons of Cs atom transfer to GaN monolayer system. Cs adsorption can reduce band gap, work function, and electron affinity, which is conducive to the escape of electrons and improvement of quantum efficiency. Cs adsorption is helpful for tuning optical properties of GaN monolayer. For the GaN bilayer, greater stability and lower work function make the Cs adsorbed above the top layer of GaN bilayer be more beneficial to the improvement of photoelectric performance. Novelty Statement: Based on first principles, this paper studies the structure and electric properties of Cs‐adsorbed GaN monolayer and bilayer. Cs adsorption can reduce band gap, work function, and electron affinity, which is conducive to the escape of electrons and improvement of quantum efficiency. And for the GaN bilayer, greater stability and lower work function make the Cs adsorbed above the top layer of GaN bilayer be more beneficial to the improvement of photoelectric performance. [ABSTRACT FROM AUTHOR]

Summary: The internet of things (IoT) is a distributed heterogeneous network of lightweight nodes with very minimal power and storage. The IoT energy system for smart applications such as smart grid, smart building, and smart transportations depends on the IoT architecture, determining the high or low‐energy consumption levels. Most of the IoT objects are power‐driven by batteries with short life spans that require replacement. The replacement phase is tedious; hence this paper comprehensively discussed the IoT energy system, energy resources, and energy storage as these three elements are crucial to enable energy efficiency for the IoT applications. In comparison to the battery‐powered solutions, the scavenging of infinite quantities of energy makes the IoT systems robust. Therefore, this paper further elaborates on understanding the current situation in terms of renewable energy harvesting for these low‐energy systems. The IoT energy storage highlighted in this paper includes fuel cell, lithium battery, and supercapacitor technology. This paper also provides the findings for IoT energy system challenges and open issues in management and storage in terms of bidirectional, continuity, autonomy, fluctuation, conversion, consumption, integration, multifunction, and stability. This paper will assist researchers in more quality yet practical energy usage and savings, better IoT system architecture, and smart application sustainability. [ABSTRACT FROM AUTHOR]

Summary: The main objective of this paper is to determine the optimal sizing of a biomass and fuel cell micro‐grid. The biomass generator will be utilized as the main source of power generation for the study area, while the fuel cell generator will be used as a backup generator to be used if the biomass generator fails to meet the energy requirements of the study area. In this research, excess energy will be used to produce hydrogen which is to be used by the fuel cells to generate energy instead of using batteries. To achieve the goal of this paper, a multi‐objective particle swarm optimization (MOPSO) technique has been proposed to solve the sizing problem for the introduced micro‐grid via an economical perspective which is the cost of energy (COE). The MOPSO algorithm tries to mitigate the COE to the lower values by keeping the loss of power supply probability (LPSP) as minimal as possible. Likewise, statistical analysis has been concluded to study the accuracy of the outcomes of the introduced technique. Three indicators have been offered, which are the process capability indices, the normal probability, and the control chart. The final contribution of the consequences of the two presented objective functions clears that the algorithm process is under statistical control, stable, and very precise. The optimum system from the economic perspective consists of two biomass gensets, 31 fuel cells, 65 electrolyzers, and 186 H2 tanks with an NPC of $ 2 314 842, COE of 0.335 $/kWh at an LPSP of 1.929%. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the newly prepared gas diffusion layer (GDL) is investigated and characterized. The GDL mainly includes the carbon paper layer and microporous layer (MPL). By the analysis of physical and electrochemical test results, it is found that the performance of GDL prepared by composite carbon black is obviously improved compared with conventional GDL prepared by single carbon black. This new GDL combines the characteristics of two original carbon materials and has a more reasonable pore structure, which can meet the good transmission of reaction gas and liquid water. Furthermore, the research shows that the pore size distribution of GDL can be effectively adjusted by changing the proportion of composite carbon black. The GDL with composite carbon black consisting of 70 wt.% Acetylene Black carbon and 30 wt.% Vulcan XC‐72 is finally confirmed to have the best fuel cell performance. [ABSTRACT FROM AUTHOR]

Summary: Lithium‐ion batteries are among the most commonly used batteries to produce power for electric vehicles, which leads to the higher needs for battery thermal management system (BTMS). There are many key concerning points for the users of these batteries, which include reliability, safety, life cycle, and the operating temperature of the batteries. It is known through review that water is the best coolant for batteries, in which the maximum temperature was 43.3°C while the temperature of the coolant was 30°C during the discharge rate of battery pack at 4 C. An effective cooling system is necessary in prolonging the battery life, which controls the temperature difference between the batteries and the peak temperature of the battery. This review paper aims to summarize the recent published papers on battery liquid‐cooling systems, which include: battery pack design, liquid‐cooling system classification, and coolant performance. Furthermore, this study discusses other factors related to the recent studies, such as the properties and applications of different liquid coolants (oil and water) under the classification of liquid‐cooling system and the difference between passive and active, indirect and direct, and external and internal cooling systems are discussed. Moreover, this paper investigates the effect of temperature on the performance of battery in three aspects: low, high, and differential temperatures. Moreover, the study provides a systematic review of liquid‐based systems for direct and indirect contact modes. [ABSTRACT FROM AUTHOR]

This paper presents a mathematical model of 255 kW grid-connected solar photovoltaic (SPV) system. To study the performance characteristics of the grid-connected SPV system, a new hybrid adaptive grasshopper optimization algorithm with the recurrent neural network (AGO-RNN) control technique was implemented. Furthermore, the power quality at the point of common coupling (PCC) has been studied using the conventional (PSO) and proposed AGO-RNN controllers. The characteristics of the PV system were analyzed under varying environmental (variable irradiance and temperature) conditions considering 3 different cases such as (i) standard test conditions (STC), (ii) variable radiation with constant temperature, and (iii) variable radiation with variable temperature. For each case, the total harmonic distortion (THD) has been calculated using the proposed AGO-RNN control technique, and the results were compared with particle swarm optimization (PSO) technique. The 255 kW PV model is initially developed and connected to a three-level NPC inverter, an MPPT-based perturbation and observation algorithm. Later, the PV model is controlled by an AGO-RNN pulse width modulation (PWM) controller and is then integrated to the main grid at PCC. The main advantage of this technique is exploiting the separate DC-DC converter between the SPV module and the inverter. Finally, the proposed grid-connected SPV system was simulated on MATLAB for analyzing the performance of the system based on its I-V and P-V characteristics, inverter voltage, grid power, gird voltage, grid current, power factor, and THD under different environmental conditions. The simulation results demonstrate that the current magnitude and THD of the SPVGC system are improved with the cutting-edge AGO-RNN controller compared to PSO in all three different scenarios, and this value is less than 1.6%, which is within the permitted limits of IEC 61727 standards. [ABSTRACT FROM AUTHOR]

While energy production is highly dependent on fossil fuels, which consider the main source of global warming, biofuels would play a significant impact in diminishing such warming. In this paper, biooils were extracted from inedible seeds (Jatropha and Castor) using different continuous devices (solvents, screw presses, and hydraulic press-machines), aiming to achieve the highest oil's yield of improved extraction properties at reduced time and energy. A wide range of engine speeds of 35, 60, 85, 110, and 135 rpm and preheating temperatures of 100, 125, 150, 175, 200, and 250°C were extensively studied to find their impact on the extraction properties. Results proved the ability of the screw press machine to extract the highest biooil yields from Jatropha and castor seeds. The optimum yield of Jatropha and castor were achieved at an extraction temperature range of 150-175°C at a motor speed of 135 rpm and a temperature range of 200-250°C at a motor speed of 35 rpm, respectively. Noteworthy, the yield of extracted castor oil is potentially solidified at low temperatures <100°C, leading oil samples to become like a dough. In contrast, lowering the temperatures of the Jatropha seeds improved the physical and chemical properties of the extracted oil. At a certain temperature (e.g., 100°C), the properties of both extracted and diesel oils are quite similar, which can be used directly in diesel engines. [ABSTRACT FROM AUTHOR]

This paper presents an energy management peer-to-peer (P2P) and peer-to-grid (P2G) trading strategy for power sharing between prosumers with grid-connected photovoltaic/wind turbine/battery storage systems. The optimal results are obtained using the "Fmincon" solver due to its ability to solve large-scale optimization problems. Two prosumers sectors are considered in this study that is the residential and commercial. The results show that for the residential consumer side, the load is satisfied by the energy from the grid, its own renewable energy system (RES), and the energy from the commercial consumer side RES during the first off-peak period (00:00 AM to 05:00 AM). During the peak pricing period (17:00 PM to 22:00 PM), the load is satisfied by the residential consumer's battery and the commercial consumer's battery, and no energy is bought from the grid due to the high price. Furthermore, 37.69% and 39.40% cost savings for residential and commercial, respectively, and a reduction of the bill by $42.26/day and $42.97154/day, respectively, are recorded. Significant grid energy savings for the developed P2P/P2G trading for prosumers and maximum daily cost savings are achieved compared to existing cases such as P2G only and P2P only. Finally, the residential consumer can achieve a greenhouse gases (GHG) emissions reduction of 141.88 kgCO2-eq and 176.99 kgCO2-eq net savings, while the commercial consumer can achieve 122.34 kgCO2-eq GHG emissions mitigation and 196.53 kgCO2-eq net savings. [ABSTRACT FROM AUTHOR]

The battery pack performance and expected lifespan are crucial in electric vehicle applications. Balancing the charge on a battery pack connected in series and parallel is crucial due to manufacturing discrepancies and distinct performance of each cell in a standard battery pack. In this paper, a switched-resistor passive balancing-based method is proposed for balancing cells in a battery management system (BMS). The value of the available voltage at the battery cell terminals is balanced using resistors in an electrical circuit, and the excess voltage is eliminated. The cell balancing outcome demonstrates that the electrical circuit can maintain an even voltage across each cell. The procedure of balancing involves individually adjusting each cell's level of charge. Passive balancing releases energy as heat by draining charge from cells that have too much charge. A passive cell balancer is a cost-effective solution and easy to install, but due to thermal loss from a resistor, it has a low energy efficiency for cell balancing and necessitates a lengthy balancing process. This passive cell balancer is an effective and reliable method for low-power devices and portable applications such as electrical vehicles. The power limits during charging and discharging are estimated using the bisection method. [ABSTRACT FROM AUTHOR]

The currently implemented indiscriminate subsidy policy in China is difficult to provide effective incentives for a firm's investment behavior because it does not take into account the differences in resource characteristics. Thus, this paper puts forward a type of differentiated subsidy that considers resource conditions, consisting of a basic guaranteed subsidy and a variable incentive subsidy. First, from the perspective of the economic efficiency of enterprises, the amount of basic subsidy required by enterprises is calculated by the discounted cash flow method. Then, from the government's perspective, a variable incentive subsidy amount is calculated by establishing an expectation benefit maximization function using principal-agent theory. The case application shows that due to the superior resources and development conditions of the Fuling block, it requires a significantly smaller subsidy amount than the Weiyuan block which verifies the need to consider regional differences in the design of shale gas development subsidies. [ABSTRACT FROM AUTHOR]

The supercritical carbon dioxide (S-CO2) power cycle is widely applicable to the utilization of multigrade heat sources due to its high efficiency and compact structure, in which the turbine is critical to the performance of the system. In this study, the operation pattern and output performance of an S-CO2 axial turbine with a design power scale of 10 kW power are investigated by experiments and numerical simulations. The loss mechanisms and distributions are analyzed using numerical simulations and loss models. The results show that the turbine output power and efficiency are at 9.66 kW and 36.6% at the designed condition and the output performance depends on the pressure ratio and rational speed. In addition, the flow field distribution reveals that the flow separation phenomenon occurs leading to loss, with the tip clearance loss being the most significant. Furthermore, the loss model validated in this paper is proven to be competent enough to fulfill the prediction of the loss distribution under different operational conditions, which could be very promising in the design of an S-CO2 axial turbine. [ABSTRACT FROM AUTHOR]

The marine industry must reduce emissions to comply with recent and future regulations. Solid oxide fuel cells (SOFCs) are seen as a promising option for efficient power generation on ships with reduced emissions. However, it is unclear how the devices can be integrated and how this affects the operation of the ship economically and environmentally. This paper reviews studies that consider SOFC for marine applications. First, this article discusses noteworthy developments in SOFC systems, including power plant options and fuel possibilities. Next, it presents the design drivers for a marine power plant and explores how an SOFC system performs. Hereafter, the possibilities for integrating the SOFC system with the ship are examined, also considering economic and environmental impact. The review shows unexplored potential to successfully integrate SOFC with thermal and electrical systems in marine vessels. Additionally, it is identified that there are still possibilities to improve marine SOFC systems, for which a holistic approach is needed for design at cell, stack, module, and system level. Nevertheless, it is expected that hybridisation is needed for a technically and economically feasible ship. Despite its high cost, SOFC systems could significantly reduce GHG, NOX, SOX, PM, and noise emissions in shipping. [ABSTRACT FROM AUTHOR]

The paper expresses the problem of flexibility pricing in energy hubs (EHs) that are in connection with electricity, heat, and gas networks considering of uncertain energy generation sources. Scheme includes a bilevel formulation. Its upper-level states for modeling of the flexibility services are provided by various resources within the EH. The problem considers maximization of the expected profit of these resources in the flexibility market. The problem constraints include the flexibility model of flexible resources such as storage devices, responsive loads, and controllable distributed generations (DGs). The flexibility model of resources relies on their active and heat power. The lower-level problem calculates energy and flexibility prices and formulates the flexible operation of energy resources considering EHs. Here, constraints include optimal power flow equations in the energy networks; operation model of EHs with power sources, storage devices, and different responsive loads; and flexibility limits of EHs. Also, a linear approximation model is adopted in the suggested design using conventional linearization techniques. Next, the Karush–Kuhn–Tucker (KKT) method is used to derive a single-level model for the problem. The scheme adopts scenario-based stochastic programming (SBSP) so that uncertainties of renewable power, energy price, load, and energy consumption of mobile storage devices are properly modeled. Finally, the results validate the suggested design's potential in modifying and enhancing the operation, flexibility, and economic situation of energy networks and EHs. [ABSTRACT FROM AUTHOR]

Wind turbines (WTs) are a desirable alternative to traditional nonrenewable power resources as a result of recent environmental concerns. Some of them are fixed speed wind generator (FSWG) and have been integrated to power system by squirrel cage induction generator (SCIG). Induction machine absorbs reactive power during all operating conditions, especially at fault condition may result in severe voltage drop which can lead to generator outage. This outage disconnects a significant amount of active power and consequently leads to frequency instability. In order to prevent induction generator (IG) outages in short circuit failures, this paper investigates thyristor-controlled series capacitor (TCSC) device as a candidate solution. TCSC compensates the IG terminal voltage drop by adjusting transmission line impedance at fault condition. In the proposed method, a metaheuristic technique means that shuffled frog leaping algorithm (SFLA) has been utilized to optimize the TCSC controller gains. The proposed scheme can be applied for both SCIGs and wound rotor induction generators (WRIGs) which is another advantage of this method. Single-machine infinite bus system is considered as case study, and various operating conditions and disturbances have been considered to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In the passive direct methanol fuel cell (DMFC) operation, the catalyst plays an important role in electrical energy production. Efficient catalyst support increases the power output and simultaneously decreases irreversible losses in the fuel cell (FC). Effective utilization of methanol at the anode end reduces methanol crossover by selecting good anode catalyst supports. In the present study, two types of anode catalyst support of carbon and carbon black are used. The two types of anode catalysts are Pt-Ru/C+ Pt-Ru/black and Pt-Ru/C along with a 2 mm thick liquid electrolyte (LE) layer placed in the middle of the two half MEAs. The LE layer is made of piled hydrophilic filter papers, which are soaked in a solution of 1 M H2SO4 concentration. The methanol concentration is varied from 1 M to 12 M and from 1 M to 5 M with and without LE-inserted FC, respectively. The passive DMFC with Pt-Ru/C+ Pt-Ru/black anode catalyst and the LE layer exhibit the best performance, producing an MPD of 5.328 mWcm-2 at a 5 M methanol concentration. The MPD produced by the anode catalyst of Pt-Ru/C+ Pt-Ru/black and Pt-Ru/C along with the 2 mm thickness LE layer incorporated fuel cell is 75.26% higher than conventional-based FC of anode catalyst of single-layer catalyst of Pt-Ru/C. [ABSTRACT FROM AUTHOR]

In this study, a coal-fired power plant with an integrated S-CO2 cycle is proposed to improve the system operational flexibility. To optimize the performance, a control strategy of variable load regulation is proposed. First, a dynamic mathematical model of the system is established based on the conservation of mass and energy principles, and then, dynamic verification of the model is carried out. In order to evaluate the performance of the proposed system, an exergy analysis is performed on the S-CO2 cycle, indicating that the exergy loss rate of the heater in the cycle is the highest. Finally, the dynamic performance of the system is simulated, and the dynamic response of the power generation load is analyzed. In addition, the system is evaluated based on the performance indicator of the flexibility of the power generation. It was found that the proposed system in this paper has a large load ramp rate which can quickly follow the load response. Meanwhile, compared with load downregulation, the system has greater potential for load upregulation. [ABSTRACT FROM AUTHOR]

In this paper, antimony sulfide (Sb2S3) nanobars were prepared via a facile poly[N-9 ′ -heptadecanyl-2,7-carbazole-alt-5,5-(4 ′ ,7 ′ -di-2-thienyl-2 ′ ,1 ′ ,3 ′ -benzothiadiazole) (PCDTBT) organic polymer-assisted hydrothermal method. The impact of PCDTBT polymer concentration on the crystal structure, shape, optical, and electrical characteristics of Sb2S3 nanobars and thin films was studied. Analysis by X-ray diffraction indicated that raising the PCDTBT concentration caused the low-crystalline structure of the Sb2S3 nanobars to transform into a polycrystalline structure. In addition, the sample had a unique Sb2S3 (orthorhombic) crystalline phase, and the crystal size increased from 32 nm to 42.6 nm. Analysis of the data revealed that the Sb2S3 nanobars had a relatively high absorption coefficient (∼105 cm−1) in the visible spectrum, with band gap values ranging from 1.71 to 1.89 eV. At a high polymer concentration, the surface morphology and grain development were enhanced, and the chemical composition analysis peaks indicate a 2 : 3 atomic ratio for Sb : S. Transmission electron microscopy (TEM) micrograph examinations demonstrate the appearance of the produced Sb2S3, which is bar-like and made of nanobars with a typical width of 200–300 nm and confirm the crystallinity of the nanobars. The optimized Sb2S3 device has a power conversion efficiency (PCE) of 5.11%, a short-circuit current density of 16.5 mA/cm2, an open-circuit voltage of 456 mV, and a fill factor of 66.62% under AM1.5G illumination. It was observed that PCDTBT has a significant role in the creation of Sb2S3 nanobars and thin films. [ABSTRACT FROM AUTHOR]

One of the essential challenges of tandem solar cells is designing and adjusting the current-matched tandem structures with high efficiency and stability. Nitride-based wide band gap semiconductors, owing to their high stability and high resistance against the cosmic rays, are appropriate elements to apply as the top cell of tandem solar cells. On the other hand, the organic-inorganic hybrid perovskites are emerging materials with exclusive electronic properties such as tunable band gap, low cost, simple manufacturing process, and efficient charge transport properties, making them capable candidates to be used in tandem layered structures. The aim of this paper is to adjust and optimize the performance of a two-terminal tandem solar cell consisting of InxGa1-xN as the top cell and a FAPbIyBr3-y as the bottom cell. We have studied the effect of different practical parameters such as the indium molar of the top cell, iodine molar of the bottom cell, the thickness of each layer, threading dislocation density of InxGa1-xN, and surface texturing effect on the performance of the two-terminal tandem structure. Because of the prominence of current matching problem in two-terminal tandem structures, we have determined the optimum situation for maximum light harvesting along with the minimum value of current matching factor. In the optimum situation, the current matching factor of 0.15 mA/cm2 leads to the power conversion efficiency of 25.17% for the device. [ABSTRACT FROM AUTHOR]

Nowadays, integration of renewable sources into the local distribution system and the nonlinear behavior of advanced power electronic equipment have made a large impact on the power quality (PQ). The unified power quality conditioner (UPQC) is a multifunctional FACTS device, which is a combination of both shunt active filter and series active filters via a common DC link. Presently, the artificial intelligence is playing a vital role in the development of the intelligent control methods. Traditional training methods of artificial neural network (ANN) like back propagation and Levenberg-Marquardt may get stuck in local optimal solution which leads to the invention of ANN trained optimally by metaheuristic algorithms. This paper develops a firefly algorithm-trained ANN (FF-ANNC) controller for the shunt active filter and proportional integral controller (PI-C) for the series active filter of the UPQC integrated with the solar energy system and battery energy storage via boost converter (B-C) and buck boost converters (B-B-C). The main aim of the proposed FF-ANNC is to reduce the mean square error (MSE) thereby achieving the constant DC link capacitor voltage (DLCV) during load and irradiation variations, reduction of imperfections in current waveforms, improvement in power factor (PF), and mitigation of sag, swell, disturbances, and unbalances in the grid voltage. The working of developed FF-ANNC was tested on five test studies with different types of loads and source voltage balancing/unbalancing conditions. However, to demonstrate supremacy of the suggested FF-ANNC, a comparative study with the training methods like genetic algorithm (GA) and ant colony optimization (AC-O) and also with other methods that exist in literature like PI-C, fuzzy logic controller (FL-C), and artificial neuro fuzzy interface system (ANFI-S) was conducted. The proposed method reduces the total harmonic distortion to 2.39%, 2.32%, 2.27%, 2.45%, and 2.66% which are lower than the existing methods that are available in literature. The FF-ANNC shows an excellent performance in reducing voltage fluctuations and total harmonic distortion (THD) successfully and thereby improving PF. [ABSTRACT FROM AUTHOR]

The flowing electrolyte in a zinc-air fuel cell (ZAFC) can reduce the problem of incomplete reaction caused by the concentration gradient of the electrolyte. In this study, we propose a self-developed ZAFC with a flowing electrolyte system and optimize control parameters. The anode of the ZAFC used Zn particles through which the electrolyte penetrates and combined with a negative pressure pump to allow the potassium hydroxide (KOH) electrolyte to have an effective chemical reaction with the Zn particles during the discharge process. However, the flow rate of the electrolyte is required to match other control parameters, such as operating temperature, KOH concentration, and cell size, to effectively improve the efficiency of ZAFC. Therefore, the Taguchi method is adopted to obtain the optimal reaction parameters and the key factors affecting the discharge efficiency of the cell. The best operation condition is the temperature at 50°C, the KOH concentration of 30% wt, and the electrolyte flow rate of 150ml/min; then, the maximum power obtained from the experimental results is 13.8 W, the maximum current density reaches 699.721 mA/cm2, and the maximum power density is 395.037 mW/cm2. This paper provides valuable insights for the upgrade of ZAFC for future practical applications. [ABSTRACT FROM AUTHOR]

Higher-order neutron fluxes (i.e., higher-order harmonics) are widely applied in perturbation theory and modal kinetics, and they are important for research on the physical characteristics of accelerator-driven subcritical reactors (ADSRs). This paper presents a computational scheme for reconstructing the neutron flux in the steady state according to the biorthogonal properties of the forward and adjoint neutron fluxes, which can be used to analyze how higher-order harmonics affect the steady-state neutron flux under λ - and prompt α -modes. Simulation results indicated that a modal synthesis method based on λ - and prompt α -modes can effectively reconstruct the steady-state neutron flux and core power in an ADSR with a power reconstruction accuracy of within 5%. The higher-order harmonics can be classified into three types according to their physical characteristics: the first type contributes significantly to the steady-state neutron flux, the second type contributes almost nothing to the steady-state neutron flux, and the third type contributes nothing to the steady-state neutron flux. The external neutron source contributes only to specific harmonic expansion orders, which are characterized by significant axial and radial symmetry for both the λ - and prompt α -modes. [ABSTRACT FROM AUTHOR]

Summary: Chemical looping hydrogen generation (CLHG) is a hydrogen production process with broad prospects for its advantages of not requiring H2 purification process and direct CO2 capture. Presently, the research on the integrated system of CLHG focuses on the impact of integrated processes and operating variables on the overall energy efficiency and exergy efficiency of the system. However, the research on the matching relationship between quantity and quality in the process of energy conversion is insufficient, and the flow direction of exergy and the specific exergy destruction process for equipment are not clear. The integrated system of coal gasification (CG) and three reactors CLHG was established in this paper with a hydrogen production efficiency of 42.55% and system exergy efficiency of 52.98%. This paper studied the exergy flow direction and efficiency of the equipment in the system, providing the improved direction for the amelioration of the system; a detailed description was present on the change process of energy quality in each equipment with energy quality factor, and the concept of energy quality factor ratio was proposed as an evaluation tool for matching the quantity and quality of energy in the system. It is calculated that the ratio of energy quality factor of the integrated system of CG and CLHG is 0.944. By comparing with the energy quality ratio of the traditional CG hydrogen production system (0.896), it can be concluded that the integrated system of CG and CLHG has a better energy matching relationship. [ABSTRACT FROM AUTHOR]

Summary: The installation of an energy storage system (ESS) is vital for the Micrgorid (MG) islanded operation to ensure the maintenance of demand–supply balance. Lithium‐ion batteries (LIBs) are among the most commonly used ESS technologies for grid‐based applications, which is used in this paper to constantly maintain the demand–supply balance in a residential MG. For this purpose, a novel frequency‐based energy management scheme is proposed. It uses an LIB ESS to handle the primary frequency control and energy management during peak‐load period, while the dispatchable distributed generators like microturbine and fuel cell supply the base load. The air‐conditioning TCLs consume a significant part of the residential load profile, especially during mid‐summer. Unlike TCLs that instantaneously use their generated cooling thermal energy to control indoor temperatures, the thermal energy storage systems (TESSs) can also store the thermal energy and use it later. In this paper, the TESSs are used instead of TCLs to reduce the power consumption of a residential Microgrid (MG) in islanded mode. By doing this, the required LIBESSs capacity is decreased 70% considerably than the case the TCLs are used for controlling the indoor temperatures. Also, replacing the ACs and EHPs with TESSs results in a 63.7% reduction in the total cost of electrical and thermal storage. [ABSTRACT FROM AUTHOR]

Summary: Human has abundant energy and can achieve energy from different human daily activities with energy harvesters. It can provide power for the wearable electronic devices, and the micro implanted electronic devices. Achieve the purpose of assisting movement, reducing metabolism, detecting life signals, and measuring metabolism level. Energy sources are mainly divided into mechanical energy and biochemical energy. According to the biomechanical energy achieved from different parts of the body, the energy harvesters are classified. The working principle, design idea, wearing style, and materials of the energy harvesters are compared and analyzed. It is indicated that the biochemical energy harvesting technology based on cell and molecular level is an innovative method which can be used for low‐power devices with great potential. While mechanical energy technology based on the principle can achieve more energy, but larger and heavy structure will lead to poor wearing experience. Meanwhile, they should complement each other and excavate human energy. This paper is not only a summary of the current research, but also points to weaknesses and outlines possible improvements that are suitable for practical applications through comparison and analysis of different energy harvesters. Novelty Statement: Human has abundant energy and can achieve energy from different daily activities. Energy sources are divided into mechanical energy and biochemical energy. The biochemical energy harvesters based on cell and molecular level is an innovative method which can be used for low‐power devices. While mechanical energy harvesters can achieve more energy. This paper provides useful information for researchers to develop energy harvesters suitable for practical application in daily life. [ABSTRACT FROM AUTHOR]

Summary: Solar steam generation has proven to be a sustainable method to handle water shortage. Various materials for solar steam generation have been introduced in the past few years. However, the utilization of tedious and complicated synthesis to generate a photoactive layer is a matter of concern in the fabrication solar steam generation devices. Thus, improved methods toward cost‐effectiveness by exploring economical materials with simple manufacturing process are urgently and essentially needed. In this study, we first report on manufacturing hybrid membranes using commercially accessible materials, that is, cellulose paper and pencil graphite. The proposed method is to trace and coat a cellulose paper directly with a pencil without the use of solvents and chemicals, and it is possible to create an ecofriendly photoactive layer without a complicated process. The formed pencil graphite‐traced membranes were successfully utilized in solar steam generation and showed excellent steam generation rate of 4.32 kg/m2h which is almost 3.5 times more than that of pristine membrane at solar intensity of 3 Sun. The developed method could be widely utilized in the field of solar steam generation, since it is very facile and simple, and can be integrated to other commonly used materials for solar steam generation such as fabric and wood. In addition, on‐site production is possible, so it has a potential to be utilized in remote and resource‐limited areas for steam generation. [ABSTRACT FROM AUTHOR]

Summary: Proton exchange membrane fuel cells (PEMFCs) can intensely lessen the emissions from the energy sector through environmentally friendly attributes. This evaluation paper summarizes the key additives of the PEMFC which are associated with water formation and delivery inside the cell. The gas diffusion layer (GDL) plays a key role in reactant gas diffusion and water control in proton exchange membrane (PEM) fuel cells. This paper also reviews updated literature regarding various hydrophobic and hydrophilic materials used for the improvement of the GDL and overall PEMFC performance. A style of carbon and steel‐based microporous substrates (MPS) and microporous layer (MPL) and their impact in GDL overall performance are provided. Materials' properties that affect the performance of the MPL consisting of pore sizes, porosity, and permeability are additionally reviewed. Visualization of water in the flow channel and techniques to understand the mechanism of flow is reported. The failure modes related to the membrane electrode assembly (MEA) and typical PEMFC degradation are discussed. Prospects for development and addressing the water management and degradation of PEMFC through the exploration of further experimental and numerical studies are presented. Highlights: Proton exchange membrane fuel cells (PEMFCs) can be a good candidate for several applicationsThe material property of the GDL influences the overall fuel performanceWater transport if not properly managed can cause poor performance and failure of the fuel cellThere is need to understand how the fuel cell failure is related to the PEMFC component materials [ABSTRACT FROM AUTHOR]

Summary: Fossil fuels demonstrate pollution effects and significant emissions on the atmosphere, which made the use of clean, renewable sources of energy a necessity. Renewable energy has many sources, but the most promising and cheapest energy source is solar energy, which has led to a focus on efficient solar energy harvesting to be cheaper for public use. Stationary solar collectors like evacuated tube and flat‐plate solar collectors are the most commonly used solar collectors for their simplicity of installation and maintenance. They are mostly used for domestic applications such as solar water heaters. Nanofluids can improve the thermal properties of the working fluid which can improve the performance of a collector. This review paper discussed the effect of different parameters on the stationary solar collector's performance, such as nanoparticle use, nanoparticle size, concentration, and the base fluid of the nanofluid. This review paper also aims to summarize previous studies performed on the use of different nanofluids on the two types of circulation that can be either thermosiphon or forced circulation for both collectors to investigate the energetic and exergetic efficiencies. The theoretical performance analysis equations of stationary solar collectors are provided too. From the reviewed results, it was concluded that a substantial improvement in both the energetic and exergetic efficiencies of both collectors had been obtained from the use of carbon‐based nanofluids compared to a significant number of different nanofluids. The paper also discusses the significant challenges of nanofluid use and how to overcome them in stationary solar collectors. [ABSTRACT FROM AUTHOR]

Summary: In situ growing conductive polyaniline (PANi) has been regarded as a functional binder to enhance the performance of silicon based anodes in half cells, while few papers discussing the influence of Mn2+ from cathode on full cells. In this paper, the effects of Mn2+ on NSi@PANi electrodes in both half and full cells are investigated, and the mechanism for the fast capacity fade of LiMn2O4/NSi@PANi full cell is elucidated. Results reveal that the full cell will significant accelerate the capacity fade of NSi@PANi anode, and the extra consumption of active Li+ and electrolytes caused by the deposited Mn2+ on silicon anodes in lithium manganate (LMO)/NSi@PANi full cells is confirmed as the main reason of the capacity fade and lower coulombic efficiency for the excessive growth of solid electrolyte interphase. [ABSTRACT FROM AUTHOR]

Summary: Computationally intelligent energy forecasting methods for appropriate energy management at the consumer/producer side have a positive impact on the preservation of energy and play a constructive role in tackling global climate change. The energy production and consumption are very high worldwide, demanding intelligent methods with real‐world implementation potentials for appropriate energy management. In this paper, we survey the existing intelligent load forecasting (ILF) systems, highlight their advantages and downsides, and briefly discuss the workflow of the employed literature. Furthermore, we debate on the existing load forecasting datasets and their features along with a brief overview of the challenges confronted by researchers using these datasets. Distinct from previous survey papers, we provide a detailed review of performance evaluation metrics and comparison of employed methods for energy load forecasting, thereby concluding the need of efficient, effective, and adoptable ILF methods functional in real‐world scenarios. Finally, we assess the employed techniques and deliver future research opportunities based on the derived conclusions from existing research works. This paper delivers the overall energy forecasting literature in a compact form with possible future insights for researchers working in ILF domain. [ABSTRACT FROM AUTHOR]

Summary: With the continuous opening of China's electricity market, a large number of third‐party electricity retailers have poured into the electricity market. Electricity retailers are the bridge between the main player of the electricity market. In view of the large number and variety of electricity retailers in the current electricity market, this paper divides the electricity retailers that have been publicized in China into five categories. In view of the uncertainty of the credit evaluation standard of electricity retailers, this paper determines the cloud model scale of the risk level of the electricity retailers; selects three primary indicators, eight secondary indicators, and 20 tertiary indicators to construct the credit risk evaluation indicator system of the electricity retailer. This paper also builds a computing model combining intuitionistic fuzzy analytic hierarchy process (IFAHP) with cloud model; obtains the final evaluation score by combining the certainty of cloud model with intuitionistic fuzzy weight, the qualitative to quantitative change of the indicator is realized, and makes the fuzzy concept of credit rating of electricity retailers get a quantitative change. From the model results, it can be seen that the risk score of the electricity grid asset retailers is 14.8666, which is the lowest risk; the independent electricity retailers has a risk score of 26.9706, which is the highest risk. Compared with the traditional AHP‐cloud model, this method is not only more objective, but also can obtain more information such as the distribution of index values from entropy and hyper entropy. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a type of small grain size vanadium pentoxide is prepared by a facile hydrothermal method. In different hydrothermal temperature conditions, X‐ray diffraction and Raman spectrum test results display that the vanadium pentoxide prepared at 140°C hydrothermal temperature has very high purity and stable layer structure. Scanning electron microscopy observes that this vanadium pentoxide displays a rather homogeneous granular morphology and the grain size can be controlled about 100–200 nm. As cathode active material for lithium‐ion battery, the specific discharge capacities can achieve 243.21, 193.83 and 143.21 mAh g−1 at 68, 170 and 340 mA g−1 current densities. After 120 cycles, the capacity retention rate is 60.52%. In addition, in this paper this small grain size vanadium oxide is successfully used as matrix material for sulfur composite cathode of lithium‐sulfur batteries. It can be found that as sulfur composite cathode at the sulfur loading mass ratio is 1:5, the specific discharge capacities can respectively reach 661.65, 514.71 and 483.13 mAh g−1 at 68, 170 and 340 mA g−1 current densities. After 150 cycles, the capacity retention rate can achieve 75.98%. [ABSTRACT FROM AUTHOR]