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Background: Researchers are keen to reduce the over potential value through fabrication of electrocatalyst consisted of environmentally benign and inexpensive material. Supercapacitors on the other hand have gained immense attention in recent years as an energy storage device due to the high power density potential of these devices as compared to conventional batteries based storage system. Aim: The research aims to synthesize nanoscale transition metal oxides (TMO) through green route. TMO based nanomaterials have vast role in energy related applications. Materials & methods: In this study, organic compounds of A. Viridis were used as reducing and stabilizing agents in the synthesis of binary nanocomposite Sb2O3-ZrO2. The synthesized nanocomposite was characterized using xray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field emission scanning electron microscopy and energy dispersive spectroscopy. The electrode material was analyzed for supercapacitor potential using cyclic voltammetry and galvanostatic charge discharge techniques. HER and OER studies were also conducted using electrochemical impedance spectroscopy and linear sweep voltammetry. The synthesized material was also tested for stability. Results & discussion: The crystal size was 15.9 nm. Optical band gap of 2.55 eV was obtained through Tauc plot. The capacitance value of 339.8 F/g at 2 mV/s and the specific capacitance of 100.6 F/g was obtained at 1 A/g. The overpotential value of 201 mV and Tafel value of 121 mV/dec was recorded for the HER, whereas the lower Tafel value of 106 mV/dec and over potential value of 383 mV was determined for OER. Electrode showed promising stability up to various cycles in case of both applications. Conclusion: The obtained results revealed the promising performance with excellent stability of fabricated electrode for super capacitor as well as water splitting studies. [ABSTRACT FROM AUTHOR]

Conducting polymers have attained a lot of interest due to extraordinary conductivity, large pore size, and surprising stability. In this work, the conducting polymer polyaniline (PANI) and niobium sulfide (NbS) were synthesized by polymerization of aniline and hydrothermal method, respectively. The PANI@NbS nanocomposite electrode material had a specific capacity (Cs) of 1050 C g−1, which is larger than that of the reference sample (NbS = 300 C g−1). Besides, the hybrid device (PANI@NbS//PANI@AC) was designed and the electrochemical characteristics were determined. The hybrid device showed an excellent value of Cs of 1207 C g−1 with higher energy density Ed and power density Pd. The device also exhibited remarkable stability, and 85 % of the initial capacity is retained after 1000 cycles. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) are substances that can change their phase at a specific range of temperatures. This is the case in the temperature range and in the event that there is a brief gap between the supply of a particular quantity of energy and the demand for that quantity, these materials come in quite helpful. As a result, heating, ventilation, and air conditioning (HVAC) for the military, as well as waste heat recovery and thermal management. The simulation result of this proposed method is developed using Matlab and Simulink, the user is classified using a fuzzy logic control which helps to improve the energy consumption patterns which are they exhibit. Using this proposed method, we can perform several modes of operations which are toogled between the control, which achieves more amount of greater flexibility, also at same time it helps to reduce the usage of number of switches which are placed between various OM's. This is demonstrated by the fact that the fuzzy logic control is used. Therefore, the developed control logic reveals a promising potential for boosting the energy efficiency. We achieve nearly 85% of accuracy as a result which are very higher than comparing with the several existing methods. [ABSTRACT FROM AUTHOR]

The quantity of photovoltaic systems generated relies on the climate, and to generate significant variations depending on the climatic conditions. Its electricity production processes exhibit unpredictability, instability, and intermittent behavior. The augmented convolutional long-short memory combination network is recommended for PV energy combined forecasting in accordance to overcome the challenge of considerable instability in the high proportion of sustainable energy output. The LSTM and CNN models' training procedure uses the enhanced artificial bee colony (ABC) to adjust their characteristics. To determine the projected model parameters of PV power, the estimated input parameters of every model are stacked and then reassembled. The studies showed that the forecast precision was significantly higher than the reliability rate of the Convolutional LSTM combinational network as well as the forecasting findings from the BP, CNN, and LSTM independent computational methods. This forecast specificity was predicated on the enhanced ABC to optimize the variables of the CLSTM combinational network for forecasting Photo Voltaic power. For comparative study and assessment, the most recent operational data from a Photovoltaic power plant in northern China have been utilized. The suggested technique resolved more quickly and was higher weather-adaptable than the individual neural network and hybrid forecasting models mentioned prior. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have attained great interest from researchers due to their excellent electrical conductivity, vast surface area, and good chemical stability. In this work, the sulphide‐based composite Ag2S@ZnS was synthesized using the hydrothermal method and was doped with CNTs in various weight percentage ratios. The structural and morphological characteristics of the samples were evaluated by employing X‐ray diffractometry (XRD), X‐ray photo spectroscopy (XPS), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and thermogravimetric analysis (TGA), while cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) were also executed for their electrochemical characterization. The performance of the Ag2S@ZnS electrode was enhanced after the doping of CNTs because of their synergistic effect. An extraordinary specific capacity (Qs) of 946.5 Cg−1 (262.91 mAh g−1) was exhibited by Ag2S@ZnS with 50% CNTs doping (Ag2S@ZnS/CNT‐50%), which is significantly greater than the reference samples. Furthermore, an asymmetric supercapacitor was designed and assessed for its electrochemical properties. The specific capacity of the asymmetric supercapacitor reached 148.62 Cg−1 (41.28 mAh g−1). The device showed improved stability and retained the 87% initial capacity after 5000 cycles. The energy and power densities were found to be 33.02 Wh kg−1 at 639.98 W kg−1, respectively, with a high value of coulombic efficiency of 92%. The device succeeded in acquiring a higher power density of 3200 W kg−1 for an energy density of 4 Wh kg−1. These astonishing results provide opportunities to design high‐performance electrode materials for extraordinary energy storage devices. [ABSTRACT FROM AUTHOR]

Hybrid supercapacitors are energy storage technology offering higher power and energy density as compared to capacitors and batteries. Cobalt-doped manganese oxide (Co@MnO2) was synthesized using an easy and affordable sol–gel process and measured the electrochemical properties. A value of the specific capacity of 1141.42 Cg−1 was obtained which was larger in comparison to the reference sample (MnO2 = 673.79 Cg−1). The value of the specific capacitance was achieved 1902 Fg−1. To design a hybrid supercapacitor device, Co@MnO2 was used as the positive electrode and the activated carbon was employed as the negative electrode in two-electrode assembly. According to calculations, the measured value of the specific capacitance of Co@MnO2 was 713.25 Fg−1. The charge storage mechanism is supported with the help of Randles–Ševčík and Dunn's models. The estimated value of energy and power densities were 3200 Wh kg−1 and 24 Wkg−1, respectively. The stability of this device was checked by putting it to 1000 charging and discharging cycles, and it retained 86% of its initial capacity. Our result provides a platform for enhancing the functionality of energy storage systems. [ABSTRACT FROM AUTHOR]

Today, many countries are focused on smart grids due to their positive effects on all sectors of a power system, including those of operators, utilities, and consumers. Furthermore, the usage of renewable energy sources for power production is quickly expanding due to the depletion of fossil fuels and the emissions caused by their use. Additionally, intermittent power generation from renewable energy sources, such as wind and solar, necessitates the use of energy storage devices with which to ensure a continuous power supply to meet demand. This can be accomplished by employing an appropriate storage device with a sufficient storage capacity, thus enabling a grid-connected solar PV and wind system to have enhanced performance and to reduce adverse effects on the power quality of the grid. In this study, a probabilistic planning model that takes the intermittent natures of solar irradiances, wind speeds, and system demands into account is introduced. A novel criterion is also adopted to map the three-dimensional spaces of intermittency with the proposed model for optimizing BESS charging/discharging decisions. This planning model is intended to minimize the economic costs of investment and operation of a battery energy storage system (BESS) for a planning period. Moreover, the substation and feeder upgrade costs, as well as the overall system loss costs, are included in the proposed model. Particle swarm optimization (PSO) is utilized to find the optimal sizing, location, and operation of energy storage systems. The proposed methodology was validated using a 69-bus distribution system. [ABSTRACT FROM AUTHOR]

Hybrid supercapacitor or supercapattery devices have gained significant attention for their impressive power (Pd) and energy densities (Ed), as well as their exceptional cyclic stability compared to traditional storage devices. In this study, manganese niobium sulfide (MnNbS) is synthesized using a hydrothermal method. To enhance the electrochemical performance of MnNbS, polyaniline (PANI) is blended at varying mass ratios. Initially, the electrochemical properties of MnNbS/PANI are evaluated using a three‐electrode configuration, consisting of working, counter, and reference electrodes. At a current density of 2 A g−1, MnNbS/PANI exhibits an improved specific capacity ((Cs)$\left(\right. C_{s} \left.\right)$) of 1366 C g−1. Subsequently, to develop a supercapattery energy storage device, a two‐electrode system is constructed. This setup offers enhanced performance and flexibility, making it an ideal choice for high‐performance supercapacitors. Activated carbon (AC) and MnNbS/PANI are employed as the negative and positive electrodes, respectively, in the two‐electrode system. Notably, the device demonstrates outstanding energy density (Ed) of 26.2 Wh kg−1, power density (Pd) of 2072 W kg−1, and specific capacity of 118 C g−1. Furthermore, durability tests involving 1000 charge–discharge cycles reveal a capacity retention of 79%. This study suggests that MnNbS/PANI (at a weight ratio of 80/20%) holds promise as an electrode material for supercapattery applications. [ABSTRACT FROM AUTHOR]

The constant changes in the load power lead permanently to a power mismatch between the power generation and the power consumption. So, the system frequency due to the power imbalance deviates from the nominal value. Consequently, a control loop should be implemented to stabilize the system frequency whenever a load change occurs. This paper presents a new super‐twisting sliding mode control methodology for obtaining an optimal frequency performance in a multi‐pool system. The paper presents a three‐pool system for frequency deviation problems using an optimal gain Super Twisting Sliding Mode Controller (STSMC), which regulates the frequency change and the line power change to zero in a minimal time. The extent of the excellence of the study proposed is evaluated by comparing it with three Benchmark classical controllers, which are the Tilt‐Integral‐Derivative (TID), Proportional‐Integral‐Derivative (PID), and Fractional‐Order PID (FOPID). The parameters of the four controllers are determined by a proposed physical meta‐heuristic optimization technique called Transient Search Optimizer (TSO), inspired by the dynamic behaviour in the electrical circuits comprising storage elements such as capacitors and inductors during the switching actions. The system simulation is performed, and the STSMC proved overwhelming superiority over other controllers, as it deals better with the transient interval of the system response. Renewable Energy sources (RESs) like photovoltaic and wind energy systems are established, and the STSMC is tested with industrial and residential load models. Finally, energy storage devices such as batteries and superconducting magnetic energy storage are implemented to suppress the rapid fluctuations in the system response, and it succeeded in doing that as the system oscillations are greatly damped with the energy storage devices. [ABSTRACT FROM AUTHOR]