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Since renewable energy is rapidly growing in the active distribution networks, the integrated energy system coupled with energy storage is a promising way to address the intermittent issues of renewable sources. This paper proposes an optimal planning model for the hydrogen‐based integrated energy system (HIES) considering power to heat and hydrogen (P2HH) and seasonal hydrogen storage (SHS) to take full advantage of multienergy complementarity. To tackle the unstable factors introduced by renewable sources and varying loads, we apply robust optimization and stochastic programming theory to improve the robustness of the planning results. Meanwhile, we also consider the N‐1 contingency constraints to make the technology selection, capacity allocation, and economic operation more reliable. The complex constraints resulting from producing two independent binary variables are converted into mixed integer linear constraints, which can be solved effectively using the nested column‐and‐constraint generation algorithm. Numerical simulation demonstrates the effectiveness of the P2HH and SHS in reducing the total cost of the HIES planning. [ABSTRACT FROM AUTHOR]

To efficiently utilize the power generated by a photovoltaic (PV) system, integrating it with an energy storage system (ESS) is essential. Furthermore, maximizing the economic benefits of such PV‐ESS integrated systems requires selecting the optimal capacity and performing optimal energy operation scheduling. Although many studies rely on rule‐based energy operation scheduling, these methods prove inadequate for complex real‐world scenarios. Moreover, they often focus solely on determining the ESS capacity to integrate into existing PV systems, thereby limiting the possibility of achieving optimal economic benefits. To address this issue, we propose an optimal energy operation scheduling and system sizing scheme for a PV‐ESS integrated system based on metaheuristic algorithms. The proposed scheme employs a zero‐shot PV power forecasting model to estimate the potential power generation from a planned PV system. A systematic analysis of the installation, operation, and maintenance costs is then incorporated into the economic analysis. We conducted extensive experiments for comparing economic benefits of various scheduling methods and capacities using real electrical load data collected from a private university in South Korea and estimated PV power data. According to the results, the most effective metaheuristic algorithm for scheduling is simulated annealing (SA). Additionally, the optimal PV system, battery, and power conversion system capacities for the university are 13,000 kW each, 10% of the PV system capacity, and 60% of the battery capacity, respectively. The estimated annual electricity tariff calculated from the data used in the experiment is $3,315,484. In contrast, SA‐based scheduling in the optimal PV‐ESS integrated system achieved annual economic benefits of $875,000, an improvement of approximately 7% over rule‐based scheduling of $817,730. [ABSTRACT FROM AUTHOR]

Flexible and stretchable supercapacitors developed on MXene‐enabled Titanium Carbide (TiC) impurities‐based electrodes with novel electrolytes are the point of focus in this work. Five different electrodes are prepared with different TiC content and symmetric supercapacitors are fabricated with three electrolytes named acrylamide, N,N′‐Dimethylacrylamide, and 2‐Hydroxyethyl methacrylate to achieve flexibility and improved energy storage. Before electrode fabrication, all the samples are tested with the X‐ray Diffraction technique. Cyclic voltammetry is performed at a potential window from −1 to 1 V to evaluate the specific capacitance of fabricated supercapacitors at multiple scan rates. Electrochemical impedance spectroscopy is performed to study the Randles circuit, and Rs values are calculated to examine the maximum physical area used for the evaluation of supercapacitors. Open‐circuit and short‐circuit tests are performed after charging the capacitor at 1 V for 2 min each time and compatibility of electrodes with different electrolytes is analyzed. The figures of merits for all the techniques used are discussed in detail. The highest values of the specific capacitances reported in our work are 50 and 79 F/g with novel electrolytes termed as N,N′‐Dimethylacrylamide and 2‐Hydroxyethyl methacrylate, respectively. [ABSTRACT FROM AUTHOR]

Given the growing demand for high‐performance, stable, eco‐friendly, and cheap lithium‐ion batteries (LIBs), the development of affordable and environmentally friendly high‐performance anode materials for LIBs has garnered considerable attention. Herein, to address this need, NiS (known for its high theoretical capacity) was grown on a porous biocarbon (BC) matrix to afford a highly conductive LIB anode material capable of accommodating the charge/discharge‐induced volume changes and thus ensuring cycle stability. The cycling performance of this material (NiS–BC) was further enhanced by doping with Fe. The best‐performing (Ni0.8Fe0.2S–BC) anode demonstrated an initial discharge capacity of 1,374.4 mAh g−1 at 0.5 A g−1, which further increased to 1,796.4 mAh g−1 after 100 cycles, and the origins of this high performance were probed by instrumental analysis. The results contribute to the development of next‐generation LIBs for applications requiring high capacity, high output, and long‐term cycle stability, such as electronic devices, electric vehicles, and energy storage systems. Moreover, the use of BC aligns with a prominent trend in modern battery research, namely, the development of secondary batteries simultaneously exhibiting high performance and sustainability. [ABSTRACT FROM AUTHOR]

The growing demand for energy storage has drawn considerable attention to devices such as supercapacitors, which currently lack high energy density but depict high power density and long cycle life. In this work, we have synthesized La0.3Sr0.7Ti0.5Fe0.5O3 (LSTF) nanoparticles and Ti3C2‐MXene‐modified LSTF nanoparticle hybrid to study the effect of MXene on electrochemical properties of the nanoparticles. The X‐ray diffraction (XRD) and Raman spectroscopy analysis showed that the hybrid structure retained all the major peaks of the nanoparticles and the MXene, which showed its successful synthesis. The morphological analysis was done utilizing scanning electron microscopy (SEM), which verified that the nanoparticles had been adsorbed and/or agglomerated onto the MXene sheets. The electrochemical analysis showed that with the addition of MXene into the nanoparticles, the specific capacitance tested via cyclic voltammetry increased from 225.6 Fg‒1 to 419.5 Fg‒1 at the scan rate of 2 mVs-1, which makes the hybrid a suitable electrode material for supercapacitors. The value of specific capacitance for the hybrid tested via galvanostatic charge‐discharge showed an increased value of 23 Fg‒1 at the current density of 1 Ag-1. The Fourier transform infrared (FTIR) spectroscopy showed that the hybrid contains –O functional groups coming from MXene, which causes an increase in electrochemical activity at the electrode surface, resulting in enhanced capacitance. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the adaptive strategies and compensatory growth mechanisms of juvenile Epinephelus coioides under starvation stress. The fish with an initial body weight of 8.88 ± 0.06 g were starved for 0 day (F0, control), 3 days (F3), 6 days (F6), 9 days (F9), 12 days (F12), and 15 days (F15), followed by feeding periods of 30 days, 27 days, 24 days, 21 days, 18 days, and 15 days, respectively. The results are shown as follows: (1) E. coioides could achieve complete or partial compensatory growth by improving both feeding rate and feed conversion efficiency. (2) The viscerosomatic index and the hepatosomatic index of the test fish decreased linearly with the duration of starvation (P < 0.05), while the condition factor did not significantly decrease (P > 0.05). At the end of feeding, all the physical body indicators of the test fish recovered or exceeded the control levels. (3) The lipid and glycogen contents of the test fish decreased continuously throughout the entire starvation process, with noticeable protein consumption occurring in the later stages of starvation (P < 0.05). At the end of the feeding period, apart from a significant reduction in crude lipid contents in the F12 and F15 groups compared to the control group (P < 0.05), the biochemical composition of the test fish was restored or even surpassed that of the control group. (4) The activity of digestive enzymes could be stimulated by starvation, enabling the efficient utilization of energy storage substances. In conclusion, it is advisable to limit the period of starvation for juvenile E. coioides to 12 days, which means that the ratio of starvation period to feeding period should not exceed two‐thirds. [ABSTRACT FROM AUTHOR]

A quaternary hybrid nanocomposite was prepared from ZnO/TiO2/GO/SA with different proportions of graphene oxide (10%, 20%, and 30%) through the use of the liquid blending method. The change in the composition of the structure of the nanocomposite was diagnosed using Raman spectroscopy, X‐ray diffraction (XRD), energy‐dispersive spectroscopy (EDS), and field emission scanning electron microscope techniques (FESEM), and the effect of changing the proportion of graphene oxide on the electrochemical performance was studied through the use of the three‐electrode system. From the results, it was found that the electrode ZnO/TiO2/GO/SA with a ratio of 30% of graphene oxide achieved the highest specific capacity of 350 F/g at a current density of 1 mA/g due to its high surface area as a result of the increased percentage of graphene oxide. Thus, it has a large number of active sites and a low internal resistance of the electrode itself. Also, this electrode achieved a high energy density value of up to 194 Wh/kg and a power density of 994 W/kg. The charging‐discharging cycles of the electrode ZnO/TiO2/GO/SA with a ratio of 30% remained stable at 98% for 5000 cycles at a current density of 9 mA/g. That means this electrode is suitable for energy storage devices such as supercapacitors. [ABSTRACT FROM AUTHOR]

This paper proposes a coordinated frequency regulation strategy for grid‐forming (GFM) type‐4 wind turbine (WT) and energy storage system (ESS) controlled by DC voltage synchronous control (DVSC), where the ESS consists of a battery array, enabling the power balance of WT and ESS hybrid system in both grid‐connected (GC) and stand‐alone (SA) modes. The newly developed GFM framework, i.e., DVSC, is adopted in both WT and ESS, which utilizes DC voltage dynamics for synchronization purposes. In this paper, the GC mode and SA mode are transferred by changing the status of the series‐connected switch, and it is necessary to meet the grid connection conditions when the system is transferred to the GC mode, namely, voltage, frequency, and phase sequence. For the GC mode, the inertia response from WT can be realized using the reserved energy of the DC capacitor, while the ESS serves to eliminate the steady‐state frequency deviation and reduce the DC voltage fluctuation of WT using the designed secondary frequency regulation scheme. For the SA mode, the proposed strategy can keep the power balance without external power sources. The small‐signal model of the WT and ESS hybrid system is derived. The stability analysis in both GC and SA modes is fully conducted utilizing the modal analysis method, where the impacts of control parameters on stability are assessed. The performance of the proposed strategy in a weak system is evaluated. Simulation studies are carried out under various power system contingencies to verify the effectiveness of the proposed strategy and validate the correctness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

Energy storage is a more sustainable choice to meet net‐zero carbon foot print and decarbonization of the environment in the pursuit of an energy independent future, green energy transition, and uptake. The journey to reduced greenhouse gas emissions, increased grid stability and reliability, and improved green energy access and security are the result of innovation in energy storage systems. Renewable energy sources are fundamentally intermittent, which means they rely on the availability of natural resources like the sun and wind rather than continuously producing energy. Due to its ability to address the inherent intermittency of renewable energy sources, manage peak demand, enhance grid stability and reliability, and make it possible to integrate small‐scale renewable energy systems into the grid, energy storage is essential for the continued development of renewable energy sources and the decentralization of energy generation. Accordingly, the development of an effective energy storage system has been prompted by the demand for unlimited supply of energy, primarily through harnessing of solar, chemical, and mechanical energy. Nonetheless, in order to achieve green energy transition and mitigate climate risks resulting from the use of fossil‐based fuels, robust energy storage systems are necessary. Herein, the need for better, more effective energy storage devices such as batteries, supercapacitors, and bio‐batteries is critically reviewed. Due to their low maintenance needs, supercapacitors are the devices of choice for energy storage in renewable energy producing facilities, most notably in harnessing wind energy. Moreover, supercapacitors possess robust charging and discharging cycles, high power density, low maintenance requirements, extended lifespan, and are environmentally friendly. On the other hand, combining aluminum with nonaqueous charge storage materials such as conductive polymers to make use of each material's unique capabilities could be crucial for continued development of robust storage batteries. In general, energy density is a key component in battery development, and scientists are constantly developing new methods and technologies to make existing batteries more energy proficient and safe. This will make it possible to design energy storage devices that are more powerful and lighter for a range of applications. When there is an imbalance between supply and demand, energy storage systems (ESS) offer a way of increasing the effectiveness of electrical systems. They also play a central role in enhancing the reliability and excellence of electrical networks that can also be deployed in off‐grid localities. [ABSTRACT FROM AUTHOR]

This paper aims to discover a novel composite material that has great potential for manufacturing high-performance supercapacitors suitable for diverse applications, such as electric vehicles, portable electronics, and stationary energy storage systems. Zeolitic imidazolate framework-8 (ZIF-8) doped by different concentrations up to 5 wt.% of nanosized Fe2O3 have been prepared (ZIF-8/Fe2O3). The effect of doping ratio 1, 3, and 5 wt.% on the structural and electrochemical properties of ZIF-8/Fe2O3 has been investigated. The structural characterization has been carried out using TGA, BET, XRD, and FTIR. The XRD analysis revealed that the crystalline size of our sample increased by approximately 16% as a result of doping ZIF-8 with 5 wt.% of Fe2O3. The structural analysis of the doped samples revealed that the material exhibited enhanced thermal stability and porosity, with an increase of approximately 105 m2/g. The introduction of doped nanometal oxides improved the capacitance value of ZIF-8 by significantly increasing its surface area. Additionally, the electron transport efficiency within ZIF-8/5 wt.% Fe2O3/electrode is increased. The Nyquist plot decreases as the doping of Fe2O3 increases. This indicates a decrease in the charge transfer resistance at the electrode–electrolyte interface, which is desired in applications such as batteries, fuel cells, or electrochemical sensors where faster electron transfer is needed for improved performance. [ABSTRACT FROM AUTHOR]

Energy storage systems (ESS) are seeing rapid market growth due to the changing worldwide landscape of electricity distribution and consumption. An ESS must possess the capability to oversee the functioning of the system's modules under abnormal circumstances, while also having the ability to supervise, manage, and optimize the performance of one or more battery modules. At present, the condition of batteries is assessed based on two factors: the level of charge (SOC) and the overall condition (SOH). By using these two characteristics, it becomes feasible to compute the anticipated battery lifespan and evaluate a battery's efficiency. The assessment of SOH is a crucial determinant in guaranteeing the effectiveness, dependability, and security of batteries in electric vehicles (EVs). Nevertheless, the safety issues resulting from the imprecise estimation and forecasting of battery health status have garnered significant attention in academic circles. This study presents a comprehensive evaluation of several SOH monitoring techniques. In order to achieve this objective, various scientific and technical literatures are examined and the corresponding methodologies are categorized into distinct groupings. The groupings are categorized based on the manner in which the procedure is executed: methods and techniques used in experiments and models. This paper provides a comprehensive overview of the benefits and drawbacks of several SOH assessment and prediction techniques, along with the associated obstacles in SOH estimation. [ABSTRACT FROM AUTHOR]

Electrochemical energy storage devices are vital for renewable energy integration and the deployment of electric vehicles. Ongoing research seeks to create new materials with innovative morphologies capable of delivering high specific capacitance for the next generation of customizable energy devices. Carbon nitride is an excellent candidate for electrochemical energy storage devices; however, it has limitations such as layer stacking, poor electric conductivity, a restricted number of electroactive sites, and static electrochemical reaction rates. This research objective is to make porous structures in carbon nitride nanosheets and integrate them with CuO particles to increase surface area and improve electrochemical performance. The use of thermal heating, acidic treatment, and hydrothermal processes accomplishes this. Along with X-ray diffraction peaks of the CuO phase, a prominent peak (002) at 27.67° indicates the presence of graphitic-structured carbon nitride. TEM images show that CuO particles are evenly attached to the surface of g-C3N4 nanosheets with lattice intervals of 0.336 and 0.232 nm, which are the (002) and (111) orientations of the g-C3N4 and CuO phases, respectively. Adding CuO nanoparticles to porous g-C3N4 nanosheets avoids layer stacking and provides micro- and mesopore channels, increasing the specific surface area (42.60m2 g-1). The CuO@ porous g-C3N4 electrode delivered 817 F g-1 of specific capacitance at 1Ag-1 and admirable capacitance retention (92.3% after 6000 cycles) due to the synergistic impact of its unique composition and structural characteristics. Because of its outstanding electrochemical performance and fascinating discoveries, CuO@ porous g-C3N4 may be employed as a cathode material for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

The red-bed soft rocks in South China have obvious creep characteristics and are prone to engineering geological disasters such as landslide and foundation settlement under the action of rainfall, groundwater, and load. In order to reveal its creep characteristics and mechanism under complex conditions, a step-loading creep test was carried out under chemical-stress-seepage coupling, and the energy evolution law of the whole creep process was analyzed based on linear energy storage and energy dissipation theory. The results also show that the acid chemical solution has the greatest influence on the triaxial strength and creep strength, and the creep damage and energy evolution of red-bed soft rock are universal. The creep damage and total strain increase with the increase of acidity, the decrease of confining pressure, and the increase of seepage pressure. The evolution law of creep damage shows the characteristics of slow-acceleration-rapid growth, and with the increase of load level, it has obvious transfer and accumulation. After entering the constant velocity creep stage, the damage rate begins to accelerate. The proportion of instantaneous strain and creep strain in the total strain increment is about 50%, and confining pressure has little influence on their respective proportions. The instantaneous strain is more sensitive to the acidity of the chemical solution, and the proportion of creep strain increases gradually with the increase of seepage pressure. The relationship between elastic energy density and total energy density is linear. The elastic energy density and dissipated energy density in the loading stage and creep stage all increase nonlinearly with loading time. The density of dissipated energy in the creep phase is lower than that in the loading phase, but the opposite is true in the higher stress phase, and the law of energy dissipation can explain the hardening damage effect in the creep process of soft rock samples. The research results provide a new perspective for us to reveal the mechanical properties and failure mechanism of red-bed soft rocks and provide an important theoretical basis for predicting and evaluating the creep instability and long-term stability of such rocks. [ABSTRACT FROM AUTHOR]

Nowadays, most of the works are based on electric vehicle usage for sustainable transportation using traditional energy storage device, such as battery. Usage of batteries in electric vehicles is having several disadvantages, for example, life span, temperature, and charge estimation. In this paper, a novel control scheme for battery and supercapacitor- (SC-) based hybrid energy storage system (HESS) using hybrid proportional and integral- (PI-) sliding mode control (SMC) for electric vehicle (EV) applications is introduced and implemented. This HESS with hybrid controller proves the usage of batteries in EVs to its fullest potential. The conventional control strategy for HESS follows two-loop voltage and current PI controllers with low-pass filter (LPF) and involves tuning of multiple control parameters with variations of source and load disturbances. Performance of the system is affected by tuning PI controller constants. A slow response time with linear PI controllers is long which is not advisable for starting and sudden jerk conditions of EVs. Moreover, the PI controller performance is affected by the system parameter variations during load changes. And these parameters are dynamic in nature due to nonideal conditions. In this paper, a hybrid PI-sliding mode controller (SMC) scheme is designed to control the bidirectional DC-DC converters to overcome the drawbacks of aforementioned issues. The combined PI-SMC controller reduces the tuning effort and reduces the effect of shift in operating point in controller performance. Linear modeling is done using small signal analysis for each subsystems. Permanent magnet synchronous machine (PMSM) is used as electric vehicle. The entire system and its controllers are simulated using MATLAB-Simulink, and detailed comparison is carried between conventional PI and proposed hybrid PI-SMC scheme to regulate the DC link voltage. The results are tabulated and show that the hybrid PI-SMC scheme outperforms in transient and steady-state conditions than the traditional PI controller. A scaled hardware prototype of 48 W set-up is developed using dSPACE-1104, and the experimental results have been carried out to verify the proposed system's feasibility. [ABSTRACT FROM AUTHOR]

The high level of integration of distributed generation systems (DGSs), especially distributed wind and solar, significantly affects the flexibility and controllability of the power system. Aggregating local DGSs and shared energy storage systems (ESSs) within an energy community offers an economically and environmentally viable solution. However, the coupling of shared ESSs with the energy community, while considering subjectivity, is often overlooked. Therefore, this study introduces a two-layer optimization framework that enables DGSs to trade energy freely, voluntarily, and independently and to share ESSs within the energy community, considering participants' subjectivity. The upper layer optimizes the size of shared ESSs, while the lower layer, structured as a two-layer model, simulates participant interactions. The numerical case shows that, compared to DGSs operating individually, the shared ESS case indicates that community self-sufficiency and self-consumption rates increase by 16.22% and 21.98%, respectively. Additionally, the annual operating cost is reduced by approximately 27.10%, and CO2 emissions are decreased by about 33.24%. Considering DGS' subjectivity, the self-sufficiency and self-consumption rates are 3.04% lower, and the total operating costs and CO2 emissions are 3.26% and 6.86% higher, respectively. [ABSTRACT FROM AUTHOR]

Environmental decarbonization drives the world to find better ways to generate and store energy. Sustainable energy in the form of solar and wind is explored with the use of conventional energy storage systems (batteries) to close the gap. Green energy generation is weather-dependent, leading to power output fluctuations, and the short-term variability in irradiance adversely affects the system's energy output and reliability. Standalone operation of a generating system necessitates a storage energy unit that manages transient loading and effectively shares power between the load and energy storage. This article presents an approach to managing energy fluctuations when renewable energy sources fluctuate, this occurs when short-term variability in irradiance, and transient loading occurs. The approach uses supercapacitors as a short-term energy storage solution. The proposed configuration has the following key advantages: effective power sharing, rapid charge, and discharge cycles in supercapacitors result in voltage restoration under transient conditions. The performance of the system is confirmed in MATLAB/Simulink. The proposed study confirms that integrating supercapacitors with PV systems does provide significant power oscillation management when sudden variations occur in renewable sources. A practical test was performed using smaller components following the same concept, and the results supported the hypothesis. The results show that the output voltage is managed when oscillation in irradiance occurs. This is seen in the simulation without supercapacitors when the output voltage fluctuates between 100 and 450 V within the first second of the simulation; however, with the introduction of SC, the voltage becomes stable and maintains an output of 620 V within 0.02 seconds. This is further supported by the experimental outcomes where almost 50% of the solar panel is covered and the output voltage is maintained. [ABSTRACT FROM AUTHOR]

Solar energy is a crucial and sustainable resource, necessitating material optimization for efficient use in solar-driven applications, particularly photocatalysis. Mixed-metallic nanocomposites, notably those derived from metal-organic frameworks (MOFs), have emerged as promising functional materials for environmental remediation and electrochemical energy storage. MOFs provide unique platforms for synthesizing diverse nanostructures, incorporating metals, oxides, sulfides, and nitrides within a porous carbon matrix. These resulting nanocomposites exhibit high crystallinity, retained morphologies, and tunable textural features. This study focuses on synthesizing a MOF-derived Ni/Zn nanocomposite (i.e., MD-Ni/Zn) from a bimetallic MOF to exploit its potential in photocatalytic pollutant degradation and electrochemical energy storage. Under UV irradiation, the MD-Ni/Zn nanocomposite efficiently degrades 98% of mixed (RhB + CV) dye within 60 minutes. This remarkable photocatalytic performance is attributed to the occurrence of mixed phases in the MD-Ni/Zn nanocomposite, minimizing the recombination efficiency of photoinduced e-/h+ through the p-n heterojunction mechanism. Electrochemical analysis reveals outstanding capacitance in the MD-Ni/Zn nanocomposite, reaching 1002 F/g at 5 A/g, emphasizing its suitability for enhanced electrochemical energy storage. [ABSTRACT FROM AUTHOR]

The present study investigates an environmentally conscious method for synthesizing silver nanoparticles (AgNPs) by employing extracts from pomegranate peel (PgP) and pineapple peel (PnP). This green synthesis approach offers a sustainable alternative to traditional chemical methods, thereby reducing the ecological footprint associated with nanoparticle production. The PgP and PnP extracts serve as both reducing and capping agents during the synthesis process, enhancing the biocompatibility of the resultant AgNPs. Various characterization techniques, including UV-Vis spectroscopy, Raman analysis, X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared (FTIR), and transmission electron microscopy (TEM), were utilized to analyze the synthesized AgNPs. UV-Vis spectroscopy confirmed the formation of AgNPs through characteristic surface plasmon resonance peaks, while FTIR examined the interaction between biomaterial components and the oxidation and coating of silver nanoparticles. Raman analysis elucidated the functional groups responsible for reducing and stabilizing AgNPs, while XRD provided insights into their crystalline structure. TEM images revealed the size and morphology of the nanoparticles, while DLS characterized their average size and morphology. In addition, the synthesized AgNPs were utilized in a bioelectrochemical cell to leverage their unique properties for enhanced electrochemical performance, showcasing their potential application in energy storage and conversion systems. Overall, this study demonstrates the feasibility of utilizing agricultural waste products such as PgP and PnP for sustainable AgNP synthesis, offering promising prospects for environmentally friendly nanotechnology advancement. [ABSTRACT FROM AUTHOR]

Heat pumps driven by sustainable electricity sources have been identified as a technology that can contribute to reduce carbon dioxide emissions. Furthermore, a heat pump can also provide energy savings when combined with a thermal energy storage system. Heat pumps can optimize their efficiency by accumulating thermal energy during periods of lower electricity demand, resulting in shorter operational durations and decreased overall energy consumption. In this work, the combination of a latent heat storage system with an air-water heat pump has been numerically analysed and experimentally tested. A phase change material (PCM) heat exchanger with an immersed plate was designed using a 3D CFD model (COMSOL Multiphysics®). The heat exchanger configuration with six steel plates immersed in the phase change material tank was proposed to enhance heat transfer in the storage system. The developed model is validated against experimental data from a real case study, demonstrating a maximum error of approximately 3% during the discharging phase. Additionally, the study explores the effects of different inlet heat transfer fluid temperatures and flow rates on the PCM solidification time. [ABSTRACT FROM AUTHOR]

This paper introduces a novel type of floating machine gun that can be simplified as a self-balancing two-degree-of-freedom mechanical system with distinct vibration characteristics. The model accounts for intricate motion patterns and encompasses numerous potential influencing factors. Multifactor combination optimization of the system represents a pressing engineering challenge. After establishing a simulation model for the machine gun and validating it experimentally, seven factors were chosen as optimization variables. The maximum recoil displacement of the inner receiver (MRD) and the firing rate were chosen to be indicators. Orthogonal combinations and variance analyses were used, and the effects of multiple factors were analyzed using SPSS software; these processes led to a determination of the optimal combination. The results indicated that the piston cylinder pressure, the bi-directional buffer spring energy storage, and the inner receiver mass significantly affected the MRD. Furthermore, the automaton mass and the reset spring energy storage were found to substantially affect the firing rate. Careful analysis of the variance results facilitated the determination of the optimal combination of parameter values. Remarkably, the optimal combination chosen resulted in an MRD reduction of approximately 20.2% and a firing rate increase of approximately 26.6%. [ABSTRACT FROM AUTHOR]

Renewable energy sources (RES) are becoming more popular globally as a reaction to critical energy concerns. Modern energy management technologies are used to maximize their efficiency while preserving the reliability of the grid. A hybrid energy storage system (HESS) connects to the DC microgrid through the bidirectional converter, allowing energy to be transferred among the battery and supercapacitor (SC). In this paper, a fuzzy logic control (FLC) technique is developed for PV-based DC microgrid systems that use both batteries and SCs. The proposed method uses the unbalanced energy from the battery pack to enhance the overall effectiveness of the HESS. The FLC approach is performed to validate under conditions of variable irradiance using MATLAB Simulink. When sudden changes in irradiance occur, the proposed FLC brings the voltage back to the desired level in terms of transient response like 33 ms settling times and 19% overshoot values. The results exhibit that the proposed method is more efficient in terms of time response, power output, increasing battery life, and ensuring a continuous supply of the PV system. [ABSTRACT FROM AUTHOR]

Manganese oxide materials for high-performance supercapacitors are as popular electrode materials of energy storage devices based on their high theoretical capacitance. However, its development is limited by its poor electrical conductivity and insufficient contact surface area, which causes the supercapacitor to fail to achieve its theoretical specific capacitance. In this paper, unique sea urchin-like MnO2/biomass carbon (BC) composite materials were prepared for supercapacitors, showing the lower resistance compared with pure MnO2, which possesses superior electrochemical performance due to the advances in outstanding electrical conductivity. The single electrode test results show that the composite material achieves a specific capacitance of 205.5 F·g−1 at the current density of 0.5 A·g−1; with the current density increasing by a factor of 20, the supercapacitor loaded with this composite still retained 63.2% of its initial capacitance, showing its high rate performance. Meanwhile, the constructed asymmetric supercapacitor can change the color of electrochromic devices and drive the light of electrochemiluminescent devices, indicating its promising application. This work provided a promising route for the rational construction of multiple dimensioned high-performance electrode materials for use in new energy storage devices. [ABSTRACT FROM AUTHOR]

The present study focuses on the green-mediated synthesis of pristine and Sm3+-doped ZnO nanoparticles using Syzygium cumini fruit extract. The prepared material was characterized by various characterization techniques. Photocatalytic degradation of a fast orange red (FOR) dye under UV light resulted in 88% degradation, with a minimal decrease (87.90%) observed even after five successive runs, indicating the stability and effectiveness of the catalyst. The enhancement in degradation efficiency is attributed to the incorporation of Sm3+ ions into the ZnO lattice. Utilizing the optimized Sm3+ (5 mol%)-doped ZnO nanoparticles, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were performed on the prepared electrode, demonstrating the excellent CV properties; this enhancement is attributed to the modification of ZnO's redox chemistry and the alteration of charge transfer kinetics at the electrode-electrolyte interface due to the addition of Sm3+ into the ZnO structure. The antibacterial activity was performed against two pathogenic strains, i.e., Escherichia coli and Streptococcus aureus. The obtained results suggest that the prepared material holds great promise for catalytic, energy storage, antibacterial, and other multifunctional applications. [ABSTRACT FROM AUTHOR]

This study examines a novel solar-assisted heat pump dryer integrated with a thermal energy storage system using soapstone as storage material. The dryer is investigated through experimental analysis across three operating modes: mode 1 with thermal energy storage during daytime, mode 2 without thermal energy storage during nighttime, and mode 3 without thermal energy storage during daytime. Experiments were carried out to investigate the drying of 500 g of Cavendish banana. Thermal performance, as well as economic, and nutritional content were examined. Three replicates of the experiment yielded consistent results, showing a significant reduction in the moisture content of the initial sample from 74.4% to 9.6% after undergoing distinct drying durations. Mode 1 achieved this reduction in 270 minutes, mode 2 in 390 minutes, and mode 3 in 360 minutes. The average specific moisture extraction rates for modes 1, 2, and 3 were 0.13, 0.11, and 0.12 kg/kWh, respectively. Simultaneously, the drying rate ranged from 0.16 to 0.24% per minute. The drying efficiency varied among the tested modes, with mode 1 achieving the highest efficiency at 23.23%. In terms of coefficient of performance, mode 1, mode 2, and mode 3 exhibited values of 3.69, 2.57, and 2.54, respectively. The economic analysis conducted specifically for mode 1 revealed a payback period of 1.5 years, indicating the time required to recover the initial investment. Additionally, the results indicated that the dried Cavendish banana had significantly higher concentrations of proximate parameters and minerals compared to the fresh Cavendish banana, as evidenced by a p value less than 0.05. [ABSTRACT FROM AUTHOR]

The renewable energy cluster can reduce the total power deviation of renewable energy stations and also bring cooperative benefits to renewable energy stations. Shared energy storage can assist in tracking the power generation plan of renewable energy and has advantages in the scale of investment, utilization rate, and other aspects. Therefore, this article proposes a study on the grid-connected optimal operation mode between renewable energy cluster and shared energy storage on the power supply side. Firstly, for the complementary characteristics blurring each member's contribution to the cluster power deviation, an improved Shapley value method is used to build a rational mechanism for apportioning the cluster power deviation penalty. Secondly, based on the Nash negotiation model and allocation mechanism, the revenue model of the renewable energy cluster is constructed, and an improved particle swarm optimization algorithm is proposed to solve the cluster operation strategy. Then, based on the charge and discharge demand of renewable energy cluster, with the goal of maximizing the benefits of shared energy storage, capacity pricing is optimized, as well as capacity allocation and participation in the frequency control auxiliary service market. Finally, the solving process of grid-connected optimal operation mode is proposed, and the rationality of the grid-connected optimal operation strategy between renewable energy cluster and shared energy storage is verified by example analysis. The results indicate that renewable energy cluster and shared energy storage can effectively increase both benefits, and a win-win situation for all parties can be realized. On the one hand, the cooperation mode and allocation mechanism can effectively guarantee the benefit of each renewable energy station. On the other hand, shared energy storage is beneficial for assisting in tracking the power generation plan of renewable energy and reducing the renewable energy power curtailment situation. There also has residual capacity in the shared energy storage system; it can participate in the frequency control ancillary service market, which can improve the capacity utilization rate and benefit of shared energy storage. [ABSTRACT FROM AUTHOR]

One of the essential capabilities of a smart distribution network is to improve network restoration performance using the postfault islanding method. Islanding of the faulty area can be done offline and online. Online islanding will decrease load shedding and operation cost. In this study, a novel two-step mathematical method for system restoration after the fault is presented. A new mathematical model for the optimal arrangement of the system for the faulty area in the first layer is proposed. In this layer, the main objective is to decrease the distribution system's load shedding and operational costs. In this regard, after the fault event, the boundary of the islanded MGs is determined. Then, in the second layer, the problem of unit commitment in the smart distribution network is addressed. In addition to the load shedding, optimal planning of energy storage systems (ESSs) and nondispatchable distributed generation (DG) resource rescheduling are also determined in this layer. The important advantages of the proposed approach are low execution time and operational costs. A demand response (DR) program has also been used for optimal system restoration. Solving the problem using the multiobjective method with the epsilon-constraint method is another goal of the paper, which simultaneously minimizes the cost and the emissions of the smart distribution network. The proposed model has been tested on an IEEE 33-bus system. Better performance of the proposed model compared to the techniques in the literature has been proven. [ABSTRACT FROM AUTHOR]

Nowadays, microgrids (MGs) are receiving a lot of attention. In an economical MG, the battery energy storage system (BESS) plays an important role. One of the biggest challenges in MGs is the optimal choice of the BESS that can lead to better performance of the MG, which will be more flexible, efficient, and effective than traditional power systems. In this paper, we present the modeling and simulation of different energy storage systems including Li-ion, lead-acid, nickel cadmium (Ni-Cd), nickel-metal hybrid (Ni-Mh), and supercapacitor (SC), for renewable energy applications, and more specifically for MGs. The results of simulation show that Li-ion batteries have a better response time than lead-acid batteries, Ni-Cd batteries, and Ni-Mh batteries and thus are more suitable for combination with supercapacitors. Li-ion batteries are the best option for fast-charging applications in MGs. The discharge phase ends with SOC ≤ ±94%, SOC ≤ ±95%, SOC = 95%, SOC < 95%, and SOC < 60%, respectively, for Li-ion, lead-acid, Ni-Cd, Ni-Mh, and supercapacitor. Moreover, the use of the battery management system (BMS) can significantly improve the performance of BESS, leading to higher levels of SOC and longer life span. The obtained results have shown that with an optimization algorithm for energy storage systems, more specifically for the battery-charging mode, the response time of BESSs can be further improved. The effect of ambient temperature has also been investigated on the functional capacities of the batteries. The obtained results demonstrated that extreme temperatures (80°C to −80°C) have a significant impact on battery performance and capacity, especially for Li-ion batteries, with a drop in capacity of up to 50% at −40°C. This highlights the importance of considering the ambient temperature in the design and operation of MGs. Overall, our study provides valuable insights into the optimal selection of BESS and the impact of ambient temperature on their performance, which can help in the development of more efficient and reliable MGs. [ABSTRACT FROM AUTHOR]

The supporting position and role of smart grids in the construction of smart cities have not been fully explored. Based on systematizing the system architecture of smart cities, we first analyze the facilitating and constraining roles of smart grids and smart cities with each other and make a quantitative analysis of the coordination and supporting roles between them; in the smart grid environment, we propose a framework of energy management system based on particle swarm optimization (PSO) dispatching model. The algorithm optimizes the operation of dispatchable loads, electric vehicles, and energy storage systems based on outdoor temperature forecasts, renewable energy power output forecasts, day-ahead tariff signals, and customer preferences to minimize customer electricity costs. The performance of the algorithm is verified through simulation experiments, and the results show that the proposed algorithm significantly reduces electricity consumption costs by 32.54% compared to algorithms that only optimize the scheduling of loads or some components of the home energy management system. [ABSTRACT FROM AUTHOR]

Electric double-layer capacitors have attracted considerable attention for energy storage because of their excellent power capability, high stability, and long cycle life. Activated carbon is the most widely employed electrode material for electric double-layer capacitors owing to its high specific surface area, hierarchical porous structure, and high electrical conductivity. However, to increase the energy density of the devices, new synthetic methods for enhancing their specific capacitances are required. We developed a facile preparation method for petroleum pitch-based activated carbon and investigated the optimal conditions to improve its electrochemical performance in terms of rate capability, specific capacitance, and cycle life. The obtained activated carbon exhibited a high specific capacitance (163.67 F/g at 0.1 A/g), which can be attributed to the efficient charge transport due to the micropores developed in the open macroporous walls of the carbon structure and the high electrical conductivity. Our approach provides an efficient strategy for synthesizing activated carbon with excellent properties. The results reveal a correlation between the physicochemical and electrochemical properties of activated carbon. [ABSTRACT FROM AUTHOR]

Today, the desire to use renewable energy as a source of clean and available energy in the grid has increased. Due to the unpredictable behavior of renewable resources, it is necessary to use energy storage resources in the microgrid structure. The power generation source and the storage source in microgrids should be selected in such a way that it has the ability to respond to the maximum demand in the state connected to the grid and operate independently. In this article, the optimal capacity and economic performance of a microgrid based on photovoltaic and battery system have been investigated. In this way, first, using the iterative optimization method, the optimal microgrid capacity has been obtained. Then, the dynamic planning method has been used for optimal microgrid energy management. The simulation results show the accuracy and efficiency of the proposed solutions. The proposed controller, while automatically and dynamically adapting to the solar cell output changes, is capable of responding to external requests, such as price signals or satisfying power system constraints or operator requests. In addition, the results indicate that by using the proposed energy management system, the microgrid system can regain stability during one to two cycles, during the occurrence of PV system radiation changes as well as ESS charge changes. And also, according to the ESS charge changes, the voltage changes should be within the defined permissible range between 0.95 and 1.05 pu, which is the result of the unique efficiency of the proposed energy management system. [ABSTRACT FROM AUTHOR]

An electric wheel hybrid power system is designed for driving a large single-aisle passenger aircraft during the take-off and ground taxi phases, which consists of an APU, an energy storage system, and a motor. In the taxi phase, the electric wheel hybrid power system works alone, and the turbofan engine does not work, reducing fuel consumption and pollution emissions. During the take-off rolling phase, the electric wheel hybrid power system and turbofan engine work together to reduce the thrust requirement of the turbofan engine. This article establishes an aircraft kinematic model, hybrid power system model, and a mechanical wheel model. The feasibility of the collaborative work of the electric wheels and the turbofan engines is verified by simulations. By utilizing the established hybrid system of electric motor wheels, the fuel consumption can be reduced, and the emissions of CO, HC, and NOX can also be diminished to varying degrees. The input of motor power leads to lower turbine inlet temperature, thereby enhancing the turbofan engine's service life by approximately 4.3% and saving operational costs. [ABSTRACT FROM AUTHOR]

In recent years, a sharp increase in integration of renewable energy sources (RESs) in power system network has been observed. High penetration of RES interfaced with power electronics converters-inverters with reduced or no inherent inertia compromises modern power system's overall stability. Due to low inertia, voltage and frequency deviations far off the allowable threshold occur. To overcome this challenge, an adaptive inertia control strategy based on optimization technique is proposed. The improved particle swarm optimization (PSO) and genetic algorithm (GA) optimization techniques-based PID controller has been used to generate the appropriate virtual inertia coefficient for effective emulation of inertia in the presence of energy storage system. The conventional PSO suffers local optima stagnation, resulting in premature convergence during searching process in order to achieve global and local position. To address this issue, the velocity update equation was modified on inertia weight (w) using an additional exponential term with linear decreasing inertia weight PSO (LDIW-PSO). In this paper, exponential power is taken strategically instead of squaring it in order to reduce the number of iterations for faster convergence. Finally, a microgrid based on wind and solar energy is simulated using MATLAB/Simulink where three cases, 2% disturbance, 3% disturbance, and 4% disturbance, have been considered. Here, the evaluation of proposed system is carried out based on four main performance indices (ITAE, IAE, ISE, and ITSE). Furthermore, validation was done through hardware prototype to get experimental results in real time. The results from MATLAB simulation and experimental setup are in sync. [ABSTRACT FROM AUTHOR]

DC–DC converters are playing a vital in the electric vehicles (EVs) application. In current EVs, a separate DC–DC converter is used to charge both in the low voltage and the high-voltage batteries. These factors have resulted in higher output voltage ripples, higher switching and device conduction losses, all of which can have an impact on EV performance. In addition, the previous mulitport converters have more number of energy storage elements and switching devices for EV application. To address these issues, this article proposes a multiport DC–DC converter charging circuit for EVs. The proposed circuit has a single-input dual-output (SIDO) structure that consists of a positive output boost converter (POBC) with integration of buck converter (POBCIBC). Here, the POBC is used to stepping-up the voltage, while the buck converter is used to step-down the voltage. The POBC is a fundamental topology composed of Cascaded Boost Super Lift Luo Converters. The designed POBCIBC has several advantages such as reduced output voltage ripples, high-voltage transfer gain, proficient efficiency, lower switching and conduction losses, less number of storage components, and a compact structure over the existing multiport converters. The performance of the POBCIBC is tested at different operating conditions by constructing the MATLAB/Simulink and prototype models. The proposed converter has produced different output voltage levels based on their duty cycles variations. The results are presented to show the proficient POBCIBC for the EV application. [ABSTRACT FROM AUTHOR]

Nanoparticles have revolutionized the landscape of energy storage and conservation technologies, exhibiting remarkable potential in enhancing the performance and efficiency of various energy systems. This review explores the versatile applications of nanoparticles in three key domains: battery technologies, supercapacitors, and solar energy conversion. In the realm of battery technologies, nanostructured particles have emerged as crucial catalysts and electrode materials, significantly elevating the energy density, cycling stability, and charge/discharge rates of batteries. By manipulating the surface chemistry and structure of nanoparticles, researchers have achieved breakthroughs in overcoming traditional limitations, paving the way for next-generation high-capacity and long-lasting batteries. The integration of tiny particles in supercapacitors has led to remarkable advancements in energy storage and rapid energy delivery. Nanoparticle-based electrodes have exhibited exceptional surface area, porosity, and conductivity, contributing to enhanced energy and power densities. The synergy of nanomaterials with novel electrolytes has also extended the operational lifespan of supercapacitors, addressing concerns regarding energy loss over cycles. Furthermore, nanoparticles have played a pivotal role in the field of solar energy conversion. In photovoltaics, nanoparticles with tailored optoelectronic properties have enabled improved light absorption, charge separation, and electron transport, ultimately boosting the efficiency of solar cells. Moreover, nanoparticles have been employed as catalysts in photocatalytic systems for solar fuel generation, driving the sustainable production of clean energy carriers. In this concise review, we highlight the recent advancements, challenges, and future prospects of nanoparticles in these critical energy domains. While the transformative impact of nanoparticles is evident, several challenges such as large-scale synthesis, cost-effectiveness, and long-term stability must be systematically addressed to ensure their seamless integration into practical energy applications. As researchers continue to explore novel synthesis techniques and innovative nanoarchitectures, nanoparticles are poised to reshape the energy landscape, accelerating the transition toward a more sustainable and efficient energy future. [ABSTRACT FROM AUTHOR]

High electricity consumption in Sarawak's cities is a concern, driven by residential, industrial, and commercial users. Greater demand for electrical energy requires more electrical resources, affecting grid stability. To prevent blackouts and enhance grid resilience, electric vehicles can serve as distributed energy storage in microgrids. The biggest problem facing energy storage is that not all batteries within energy storage are the same. Every battery cell in the battery pack has a different rate of self-discharge, capacity, internal resistance, and aging, even though they have the same chemical and physical characteristics. These variations lead to power imbalances in energy storage. Therefore, to address this issue, a unique voltage equalization method using a modular flyback converter is presented. Its core objective is to correct voltage imbalances among batteries. The proposed method is modelled using MATLAB, and the performance of the system has been evaluated. Furthermore, the developed model is implemented in a microgrid and tested for two different cases (with and without energy storage for electric cars). From the simulation outcomes, it has been verified that the developed cell balancing technique performs well in equalizing the voltage of cells than the conventional methods. [ABSTRACT FROM AUTHOR]

As the proportion of renewable energy increases in power systems, the need for peak shaving is increasing. The optimal operation of the battery energy storage system (BESS) can provide a resilient and low-carbon peak-shaving approach for the system. Therefore, a two-stage optimization model for grid-side BESS is proposed. First, the carbon emission model of thermal power units considering BESS is proposed to describe the ability of the BESS in reducing the carbon emissions. Second, in order to deal with the uncertainty of the photovoltaics and wind forecast errors, a certain capacity of BESS is reserved. The model in the first stage takes the lowest carbon emission of the system as the goal, and the model in the second stage determines the BESS reserve capacity with the objective of minimizing the risk cost of the system. The simulation results show that the carbon emission model of thermal power units with BESS can measure the contribution of energy storage to emission reduction. By setting the reserve capacity of energy storage, the peak-shaving resilience of the system is improved, and the risk of photovoltaics and wind forecast error is reduced. [ABSTRACT FROM AUTHOR]

Energy storage technologies (ESTs) play a crucial role in ensuring energy security and addressing the challenges posed by climate change. They enable us to overcome the mismatch between energy supply and demand caused by the intermittent and unpredictable nature of renewable energy sources. The identification of research frontiers in ESTs has primarily relied on expert experience and has been limited to specific areas of study. However, there is a relative lack of data-driven approaches to identify these frontiers. In this study, we employed an integrated technique combining bibliographic coupling and sliding window analysis to identify the research frontiers in ESTs and understand their evolution over time. Our study reveals 19 research frontiers in ESTs distributed across four knowledge domains: electrochemical energy storage, electrical energy storage, chemical energy storage, and energy storage systems. Among these frontiers, two noteworthy areas are aqueous zinc batteries (AZBs) and two-dimensional transition metal carbon-nitride composites (MXenes). By identifying these research frontiers, our study provides insights into the potential future directions for research and development (R&D) deployment in energy storage technologies. [ABSTRACT FROM AUTHOR]

Owing to their high latent heat enabling thermal energy conservation upon heat absorption and release, phase change materials (PCMs) are attracting increasing interest for use in thermal energy storage systems and next-generation thermal management systems. However, they have limitations such as inherently poor thermal and mechanical properties, which hinder their practical use. To overcome these limitations, we prepared a novel PCM based on polyimide- (PI-) grafted erythritol (PIET) through in situ grafting and imidization using PI. PIET composites that were prepared using oxidized expanded graphite as a filler showed an improved thermal conductivity of 2.56 W·m-1·K-1 in the through-plane direction, a latent heat of 192.5 J·g-1, and a tensile strength enhanced by 119%. Thus, the prepared PCM composites showed the potential for the development of advanced PCMs. [ABSTRACT FROM AUTHOR]

Recently, Zeolitic Imidazolate Frameworks (ZIFs) and their hybrid composites have incited a lot of interest in the research community and have shown promising potential in supercapacitors owing to their excellent conductivity, high surface area, tunable structure, rich redox chemistry, composition diversity, etc. Even though many ZIFs are being studied for the advancement of electrode materials used for energy storage applications, in this review, we are focused on ZIF-8 and ZIF-67 only. The electrochemical performance of pure ZIFs is poor due to low electronic conductivity and poor cycling life. To counter this, ZIFs are mixed with other materials like conducting polymers, other transitional metals composites, and activated carbons to prepare hybrid composites. Furthermore, the highly porous structure and large surface area of the ZIFs cage act as an ideal template for designing composites with excellent supercapacitor applications. This reviewis focus on the synthesis and electrochemical performance of such materials. This review is divided into two main parts: the design and synthesis of ZIF-8 and ZIF-67 derivatives for supercapacitor applications and the electrochemical performance of ZIF-8 and ZIF-67-based derivatives in three-electrode and two-electrode setups. Lastly, the challenges and obstacles encountered while employing ZIF-8 and ZIF-67-based composites in supercapacitors will be reviewed and commented on. [ABSTRACT FROM AUTHOR]

This paper proposes and analyses several configurations for hybridising concentrating solar power (CSP) plants with combined cycle gas turbines (CCGT). The objective is to increase the solar contribution to a large extent, much higher than those obtained in integrated solar combined cycles but maintaining synergies, which are usually lost when increasing the solar share. For that, two thermal energy management systems are introduced at different temperature levels. First, a configuration with only the low-temperature system is proposed. Then, an enhanced configuration with the low- and high-temperature systems is conceived. These configurations are compared to reference CSP and CCGT state-of-the-art plants. The analyses include different strategies of operation and two sizes for the thermal energy storage system. The results show that the first proposed configuration introduces some synergies but cannot improve the performance of the reference CSP and CCGT working separately, due to an issue with the solar dumping on days with high solar irradiation. The enhanced configuration overcomes this problem and maintains the synergies, leading to an improvement from both the thermodynamic and economic points of view, increasing the solar contribution and decreasing the levelized cost of energy over the reference plants. [ABSTRACT FROM AUTHOR]

Evaporative cooling is an efficient approach for removing heat from nuclear reactors, solar power plants, solar panels, and energy storage devices, such as lithium-ion batteries and fuel cells. Nanotextured surfaces can provide improved evaporative cooling by increasing the total surface area to enhance the heat transfer rate and reducing the temperatures of local hotspots. In this study, we introduced rhombic dodecahedral zeolitic imidazolate framework-8 (ZIF8), a class of metal-organic frameworks, via impregnation to create nanotextured surfaces. The impregnation time was varied to obtain various thicknesses of ZIF8. We found that the increased surface area of ZIF8 improved convection cooling, which considerably reduced the temperature of the heated substrate. Air, mist (buoyant aerosols), and spray (inertial droplets) were independently used as coolants to compare the cooling performance of noncoated (bare) and ZIF8-coated substrates. Compared to the noncoated substrate, the optimal ZIF8 film yielded temperature reductions of Δ T = 13 °C and 10°C for air and spray cooling, respectively. [ABSTRACT FROM AUTHOR]

In this research, a solar photovoltaic system with maximum power point tracking (MPPT) and battery storage is integrated into a grid-connected system using an improved three-level neutral-point-clamped (NPC) inverter. An NPC inverter with adjustable neutral-point clamping may achieve this result. To achieve this result, a modernized NPC inverter is used. Using the three-level vector modulation approach, the correct AC voltage may be generated when DC voltage conditions are present in an unbalanced situation involving an NPC inverter. A higher degree of precision is made possible by this. In-depth information on the many possible NPC inverter designs and modulation strategies was provided. By incorporating the necessary sophisticated algorithms into the NPC inverter, the necessary solar PV-MPPT functionality is made available, allowing for the regulation of power transfer among the solar PV system, the battery, and the grid. Modified INC method is proposed which has a tracking efficiency of 99.5% for varying irradiance. The use of sufficiently sophisticated algorithms makes this a reality. Using simulation with MATLAB/Simulink, we were able to examine an NPC inverter's performance in several setups. Several amounts of solar irradiation were used to test the battery's charging and discharging capabilities. The probe turned out to be fruitful. Laboratory testing ensures that the proposed method works by simulating real-world conditions. [ABSTRACT FROM AUTHOR]

A flexible piezoelectric nanogenerator (PENG) was developed to convert ambient mechanical energy into electrical energy. Highly crystalline template-free zinc oxide (ZnO) microrods were prepared using a wet chemical method at a low temperature. As-synthesized ZnO microrods were blended with polyvinylidene fluoride (PVDF) to prepare a piezoelectric composite film using the supersonic spraying method. A PENG electrode comprising ZnO microrods (0.5 g) produced 15.2 V under a tapping force of 20 N at 5 Hz. In addition, an output current of 32 μA was produced with a maximum power density of 12.5 μW cm–2. The output voltage considering various body movements was investigated to demonstrate the flexibility and durability of the proposed PENG. Furthermore, the supercapacitive properties of ZnO/reduced graphene oxide were studied. [ABSTRACT FROM AUTHOR]

Nowadays, there is constant demand for the development of energy storage materials using advanced methodologies. In this scenario, a large-scale environmentally friendly synthesis was chosen to prepare Ni-Co-layered double hydroxide (LDH) composites for asymmetric supercapacitors. The developed materials had a flower-like porous architecture with very low dimensional layers and a large surface area. The developed Ni-Co/LDH composite electrodes showed impressive specific capacitance of 1095.1 F/g at a current density of 1 A/g and maintained 492.5 F/g even at a current density of 20 A/g. In particular, the Ni-Co/LDH composites maintained 86.9% of their initial capacitance even after 5000 cycles at a high current density of 2 A/g. Furthermore, an asymmetric supercapacitor with Ni-Co/LDH composites demonstrated an excellent energy density of 40.7 Wh/kg at a power density of 750 W/kg. [ABSTRACT FROM AUTHOR]

A 3D-printed multicoupled piston-type cylindrical triboelectric nanogenerator (MPC-TENG) that utilizes contact-separation and lateral-sliding operational modes to harvest rotational motion and convert it into electricity was proposed. The electrical performances of the fabricated four similar piston-type cylindrical TENGs (PC-TENGs) were systematically investigated. TENGs in general produce electricity in an alternating-signal form which may not be used to directly power electronic devices. Therefore, all the individual PC-TENGs were connected with a simple external filter circuit to obtain direct current (DC) electrical output, and further, they were parallelly connected to increase the overall electrical output from the MPC-TENG. The MPC-TENG consists of four PC-TENGs and produces a DC electrical output of ~40 V and ~12.5 μA at 380 rpm. Furthermore, the MPC-TENG was attached to wind cups to harvest wind energy and a Pilton wheel to harvest hydrokinetic energy, respectively. The harvested energy was stored in energy storage devices to power various small-scale electronic gadgets. Furthermore, a real-time self-sustaining alarm combined with the MPC-TENG was demonstrated to detect unauthorized human/wild animal entry into a protected region. This work also shows that the DC electrical signals from the proposed MPC-TENG can be further increased by combining more PC-TENG devices. [ABSTRACT FROM AUTHOR]

There is a desperate demand for efficient energy storage systems to fulfill future energy demands. Herein, we exemplify a facile solvothermal approach followed by heat treatment to synthesize NiO/g-C3N4 nanocomposites for enhanced supercapacitor applications. The molar ratio of g-C3N4 is varied to achieve numerous nanostructures like nanoparticles and nanorods with optimum specific capacitance. Further, all as-prepared electrode materials are examined for supercapacitor application. The electrochemical behavior of prepared NiO/g-C3N4 nanocomposites is carried out under cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) in a three-electrode cell under different electrolytes such as aqueous sodium sulphate electrolyte (1.0 M Na2SO4) and potassium hydroxide electrolyte (3.0 M KOH). Among all the electrode materials, NO-4 (1 : 2) shows the highest specific capacitance of 338.68 F/g at a scan rate of 2 mV/s and 161.3 F/g at a current density of 1 A/g in 1.0 M Na2SO4 electrolyte. Also, this electrode material shows 95.22 F/g at a scan rate of 2 mV/s in 3.0 M KOH electrolyte. The excessive specific capacitance of this electrode material is due to retarded charge transfer resistance in the interface at the electrode and electrolyte and a increased number of active sites. The investigation of the electrokinetics of all the prepared electrodes was also carried out, and it revealed the charge storage contribution of capacitive and diffusive parts which levitates the higher specific capacitance. The two-electrode study for evaluating supercapacitor performance is studied. The NO-4//NO-4 SSD in 1.0 M Na2SO4 electrolyte shows 18.23 F/g at a specific capacitance of 1 A/g with a corresponding energy density of 10.13 Wh/kg and a power density of 1.01 kW/kg, respectively. [ABSTRACT FROM AUTHOR]

Power quality is the main problem with the power system network. Poor electricity quality may cause disruptions and financial challenges for consumers. Additionally, it could cause electronic gadgets to overheat, be damaged, or operate inadvertently. Transformers and other components of the power distribution system may also overheat and experience core saturation. This study investigates potential problems with the quality of the electricity in a photovoltaic linked power system. This paper suggests a new optimization method for day-ahead trading and control in DC microgrid power management (MG). The goal of the multiobjective optimization dispatch (MOOD) problem is to lower overall operational costs as well as the costs associated with power loss in efficient conservation systems and exhaust emission quantities such as nitrogen oxides, sulphur dioxide, and carbon dioxide. Using the weighted sum approach, the multiobjective optimization problem is reduced to a single optimization problem. The analytical hierarchy process (AHP) method is then used to calculate the weight coefficients while accounting for each objective function's preferences. Power balancing, high levels of renewable energy penetration, the most effective scheduling of battery charging and discharging, control of load curtailment, and the technical limitations of the system are all taken into account when evaluating the system's performance in both grid-connected and standalone operation modes. The ant lion optimizer (ALO) technique is taken into account to tackle MOOD, comparing the effectiveness of the proposed method to other well-known heuristic optimization techniques. The simulation's results demonstrate how effectively the proposed strategy can address the coordinated control and optimization dispatch difficulties. They also found that operating the MG system economically in grid-connected mode can save overall costs by roughly 4.70% compared to doing it in independent mode. [ABSTRACT FROM AUTHOR]

It is crucial to develop a low-cost hybrid electrocatalysts for hydrogen production. Due to their layered structure and strong electrical conductivity, MXene-based materials have been lately used more and more in energy storage devices. Herein, heteroatom- (boron and sulfur-) doped MXene (B, S-Ti3C2Tx) nanosheets are developed as efficient electrocatalysts for the hydrogen evolution reaction (HER). The synthesized B, S-Ti3C2Tx has a large surface area and exhibits excellent electrocatalytic activity in acidic media. The prepared B, S-2-Ti3C2Tx catalyst exhibits a low overpotential of −110 mV vs. reversible hydrogen electrode for the HER and a low Tafel slope of ∼54 mV dec−1. Furthermore, B, S-2-Ti3C2Tx shows a double-layer capacitance of 1.05 mF/cm2 and maintains a steady catalytic activity for the HER for over 1000 cycles. [ABSTRACT FROM AUTHOR]

Megawatt-impulse power generated by Tokamak fusion devices seriously threats to the stable operation of the whole system. The current power supply scheme needs to leave large redundancy to suffer such a huge power impact, resulting in a high cost of the power supply system. Moreover, no reasonable configuration for impulse power and stable power causes unnecessary waste of power supply capacity. The rapid development of energy storage technology provides a potential approach to solve the operation stability problem caused by large amounts of power impact. Thus, a novel hybrid power supply scheme is creatively put forward with centralized energy storage, which can effectively decrease the voltage level of the grid and achieve smooth connection into the public grid when validly compensating for the impulse power. The cost evaluation model and principles are proposed to analyze and assess the economic advantages of the hybrid power supply scheme with centralized energy storage. Finally, a power scenario based on the international thermosnuclear experimental reactor (ITER) is applied as a case study of the cost evaluation model for various schemes, and the results verify that the novel hybrid power supply scheme has benefits on economics and the capacity of the grid over other schemes. [ABSTRACT FROM AUTHOR]

Electrode materials for large-scale applications from the earth-abundant material need to be developed in the energy storage system. Based on earth-abundant material, sodium-based batteries with Fe system-based positive electrodes seem attractive for a cost-effective system for large-scale storage applications. Instead of partial substitution of transition metals with Fe, in the present work, we choose surface coating to analyze the electrochemical performance of NaFeO2. SnO was coated on the NaFeO2 surface, and the electrochemical characteristic property is studied in detail. Spongy nanoball coating is confirmed on the surface of NaFeO2. The reversible capacity of SnO-coated NaFeO2 is about 158 mAh·g-1 at 0.25 C. The SnO coating greatly enhances electron transport during cycling, and 80% of capacity is retained after 1000 cycles. The enhanced electrode can be used as a cost-effective, eco-friendly natured electrode with high performance for large-scale energy storage applications. [ABSTRACT FROM AUTHOR]