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This paper is aimed at modelling of a distinct smart charging station for electric vehicles (EVs) that is suitable for DC quick EV charging while ensuring minimum stress on the power grid. Operation of the charging station is managed in such a way that it is either supplied by photovoltaic (PV) power or the power grid, and the vehicle-to-grid (V2G) is also implemented for improving the stability of the grid during peak load hours. The PV interfaced DC/DC converter and grid interfaced DC/AC bidirectional converter share a DC bus. A smooth transition of one operating mode to another demonstrates the effectiveness of the employed control strategy. Modelling and control of the different components are explained and are implemented in Simulink. Simulations illustrate the feasible behaviour of the charging station under all operating modes in terms of the four-way interaction among PV, EVs and the grid along with V2G operation. Additionally, a business model is discussed with comprehensive analysis of cost estimation for the deployment of charging facilities in a residential area. It has been recognized that EVs bring new opportunities in terms of providing regulation services and consumption flexibility by varying the recharging power at a certain time instant. The paper also discusses the potential financial incentives required to inspire EV owners for active participation in the demand response mechanism. [ABSTRACT FROM AUTHOR]

ABSTRACT ZnS is a candidate to replace CdS as the buffer layer in Cu(In,Ga)Se2 (CIGS) solar cells for Cd-free commercial product. However, the resistance of ZnS is too large, and the photoconductivity is too small. Therefore, the thickness of the ZnS should be as thin as possible. However, a CIGS solar cell with a very thin ZnS buffer layer is vulnerable to the sputtering power of the ZnO : Al window layer deposition because of plasma damage. To improve the efficiency of CIGS solar cells with a chemical-bath-deposited ZnS buffer layer, the effect of the plasma damage by the sputter deposition of the ZnO : Al window layer should be understood. We have found that the efficiency of a CIGS solar cell consistently decreases with an increase in the sputtering power for the ZnO : Al window layer deposition onto the ZnS buffer layer because of plasma damage. To protect the ZnS/CIGS interface, a bilayer ZnO : Al film was developed. It consists of a 50-nm-thick ZnO : Al plasma protection layer deposited at a sputtering power of 50 W and a 100-nm-thick ZnO : Al conducting layer deposited at a sputtering power of 200 W. The introduction of a 50-nm-thick ZnO : Al layer deposited at 50 W prevented plasma damage by sputtering, resulting in a high open-circuit voltage, a large fill factor, and shunt resistance. The ZnS/CIGS solar cell with the bilayer ZnO : Al film yielded a cell efficiency of 14.68%. Therefore, the application of bilayer ZnO : Al film to the window layer is suitable for CIGS solar cells with a ZnS buffer layer. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT A barrier layer of undoped TiO2 was deposited on the Nb-doped TiO2 electrode to suppress the recombination at the Nb-doped TiO2/dye-electrolyte interface for highly efficient dye-sensitized solar cells (DSCs). The Nb content in TiO2 was varied in a range of 0.7-3.5 mol% to modify the TiO2 energy-band structure. Nb-doped TiO2/dye interfaces were characterized by a combination of ultraviolet photoemission spectroscopy and optical absorption spectroscopy measurements, allowing the determination of the conduction band minimum (CBM) of the TiO2 electrode and the lowest unoccupied molecular orbital of the N719 dye. The lowering of TiO2 CBM by Nb doping induced the increase in short-circuit current of DSCs. However, open-circuit voltage and fill factor are decreased, and this result was ascribed to the enhanced recombination at the Nb-doped TiO2/dye-electrolyte interface. The effect of doping on charge transport in DSCs was analyzed using electrochemical impedance spectroscopy. We have shown that by introducing of TiO2 barrier layer, the Nb doping content, which results in DSC highest efficiency, can be increased because of the suppression of the dopant-induced recombination. The energy conversion efficiency of the solar cells increased from 7.8% to 9.0% when undoped TiO2 electrode is replaced with electrode doped with 2.7 mol% of Nb because of the improvement of the electron injection and collection efficiencies. The correlation between the electronic structure of the TiO2 electrode, charge transfer characteristics, and photovoltaic parameters of DSCs is discussed. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents look-ahead energy management system for a grid-connected residential photovoltaic (PV) system with battery under critical peak pricing for electricity, enabling effective and proactive participation of consumers in the Smart Grid's demand response. In the proposed system, the PV is the primary energy source with the battery for storing (or retrieving) excessive (or stored) energy to pursue the lowest possible electricity bill but it is grid-tied to secure electric power delivery. Premise energy management scheme with an accurate yet practical load forecasting capability based on a Kalman filter is designed to increase the predictability in controlling the power flows among these power system components and the controllable electric appliances in the premise. The case studies with various operating scenarios demonstrate the validity of the proposed system and significant cost savings through operating the energy management scheme. [ABSTRACT FROM AUTHOR]

One of the major world wide concerns of the utilities is to reduce the emissions from traditional power plants by using renewable energy and to reduce the high cost of supplying electricity to remote areas. Hybrid power systems can provide a good solution for such problems because they integrate renewable energy along with the traditional power plants. In Kingdom of Saudi Arabia a remote village called Al-Qtqt, was selected as a case study in order to investigate the ability to use a hybrid power system to provide the village with its needs of electricity. The simulation of this hybrid power system was done using HOMER software. [ABSTRACT FROM AUTHOR]

An environmental chamber has been constructed at Arizona State University to establish a long-term aging test of all-dielectric self-supporting (ADSS) fiber-optic cable. A polymer-jacketed ADSS (track resistant) cable is subjected to UV radiation, salt fog, clean rain, and mechanical tension in the aging chamber. Installed by the Bonneville Power Administration (BPA), a similar track resistant ADSS has been in operation for about eight years, near the Pacific Ocean at Bandon, OR. Accumulated pollution on this ADSS has been measured by BPA on approximately a semiannual basis. In this paper, the aging chamber operation is outlined briefly and two methods of measuring the accumulating pollution level on the ADSS cables in the aging chamber are described. The accumulated pollution levels of both ADSS cables in the chamber and in Bandon, OR, are compared. It is noted that general chamber performance compares favorably to the field data as well as suggesting an approximate chamber-aging rate, about 18:1. [ABSTRACT FROM AUTHOR]

Insulation is identified as one of the most important constructional rudiments of a transformer, and any weakness of insulation would lead to a transformer failure. To check the insulation integrity, a sensitive technique like the standard impulse test is used. Testing of winding insulation is performed by comparing the voltage and current waveforms of reduced and full test voltages, previously. Transfer function has been exercised via applying fast Fourier transform to analyze the transformer state in the frequency domain. In order to enhance the fault detection sensitivity in transformer impulse test, this paper proposes a new method using short time Fourier transform in the transfer function analysis, derived from experimental works on 25 kVA and 26 MVA transformers. It is concluded that the fault detection sensitivity is improved significantly by using STFT analysis, including minor faults. [ABSTRACT FROM AUTHOR]

This article describes a technique for improving the performance of an offshore wind farm (OWF), which includes a permanent magnet synchronous generator (PMSG) driven by a variable‐speed wind turbine (VSWT) and connected to the grid through a high‐voltage direct current transmission system (HVDC). Under various network disturbances, the gorilla tropical optimization (GTO) metaheuristic method is used to fine‐tune the proportional‐integral (PI) controller gains for VSC‐based PMSG‐VSWT and VSC‐based HVDC transmission systems. This study compares several strategies for extracting the maximum power from a system while maintaining stability under symmetrical and unsymmetrical fault circumstances. Compared to different algorithms, GTO provides better results and improves system recovery and stability after disturbances. As a consequence, dynamic and transient stability may be enhanced. MATLAB/Simulink is used to implement the control mechanism. [ABSTRACT FROM AUTHOR]

In this study, we have synthesized facile Cu‐based CuO:Er2O3 nanoelectrode material for energy storage and generation. CuO:Er2O3 nanomaterial was synthesized employing phyto‐extract of Amaranthus viridis L. (AVL) as stabilizing and reducing agents. Spherical‐shaped CuO:Er2O3 nanomaterial was initially employed to study supercapacitor behavior. The specific capacitance of 82.25 F/g was found at 0.5 A/g by galvanostatic charge–discharge, whereas the value of 319 F/g was achieved at 2 mV/s by cyclic voltammetry (CV) measurements. Furthermore, CuO:Er2O3 electrode was investigated for water splitting energy generation potential and revealed an overpotential value of 323 mV at 10 mA/cm2 for hydrogen evolution reaction (HER). However, for the oxygen evolution reaction (OER), an overpotential value of 370 mV was found. The electrochemical impedance analysis revealed the faster flow of electrons and ions, suggesting great conductivity and lower resistance of the fabricated electrode. Thus, current electrochemical results are proposing CuO:Er2O3 as an competent electrode for overall energy‐generating as well as storage applications. [ABSTRACT FROM AUTHOR]

• Vehicle-to-Grid (V2G) framework permits bi-directional power flow from a vehicle's battery to the power grid. • A deterministic and a probabilistic method of PHEV charging/discharging schedule are analyzed and their performances are compared based on a case study at Riyadh city, Saudi Arabia. • On the deterministic method, an optimization model is proposed to reduce overall grid power consumption for utilities and operate smart charging and discharging schedule for PHEV users. • The probabilistic method uses Monte Carlo Simulation (MCS) to analyze the impact and determine a coordinated Time of Unit (TOU) type for PHEV charging/ discharging schedule. Within the next decade, the number of electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) will increase exponentially owing to the environmental benefits related to their utilization. In an ideal framework condition, the vehicle-to-grid (V2G) system provides advantages such as subordinate administration of load leveling and peak shaving guidelines, and minimized upgrade costs. In this paper, deterministic and probabilistic methods of scheduling PHEV charging/discharging are analyzed, and their performances are compared based on a case study. In the case of the deterministic method, an optimization model is proposed to reduce the overall grid output power consumption for utilities and operate a smart charging/discharging schedule for PHEV users. Quadratic programming (QP) is used to solve the optimization cost function. In contrast, the probabilistic method uses Monte Carlo simulation (MCS) to analyze the impact and determine a coordinated time-of-use (TOU) structure for the PHEV charging/discharging schedule. Both methods suggest V2G feasibility for the smart grid system. [ABSTRACT FROM AUTHOR]

Using single‐source precursor route, this work reports the synthesis of the novel chalcogenide heterosystem, i.e., BaS:CoS:La2S3 trichalcogenide heterosystem. With the narrowed band gap energy, BaS:CoS:La2S3 expresses excellent photonic response with 3.47 eV of tailored band gap resulting from chemical synergism. This chalcogenide is marked by superior crystallinity and possessed an average crystallite size of 18.29 nm. Morphologically, BaS:CoS:La2S3 exists in the form of the roughly spherical grains arranged in the irregular manner. The developed chalcogenide is assessed for charge storage by fabricating the electrode using a nickel form as a support. In a 0.1 m KOH background electrolyte, the BaS:CoS:La2S3 adorns electrode excelled in achieving a specific capacitance of 967.24 F g−1. In addition, this trichalcogenide expresses the specific power density of 1659 W kg−1. Fabricated electrode retains original capacitance after different cycles. Regarding electrode–electrolyte interactions, the fabricated electrode shows minimal resistance, with an equivalent series resistance (Rs) of 1.42 Ω as indicated by impedance studies. Additional circuit elements, including CPE (Yo = 2.17 × 10−04, n = 0.71) and Rct (6.97 Ω cm−2), are obtained after circuit fitting for the BaS:CoS:La2S3 trichalcogenide decorated electrode. Exhibiting stable behavior for 43 h, the synthesized material demonstrates profound durability and functionality. [ABSTRACT FROM AUTHOR]

Electrodeposition, a binder-free technique, enables the formation of uniform and well-defined structures on the electrode surface. Herein, the material has directly grown on nickel foam by deposition through cyclic voltammetry at a fixed scan rate. The surface morphology of as-synthesized electrodes is observed with SEM and the electrochemical examination has been performed in three-electrode assembly. The highest specific capacitance attained from GCD analysis for MnS is 1453 F/g, CoS has 2476 F/g and CuS exhibits 1908 F/g at 6 A/g current density. The quantitative investigation of the inherent charge storage mechanism of an individual electrode is achieved by implementing different mathematical models on experimental data sets. The electrodes displayed a more diffusive contribution which uncovered our findings that each electrode illustrates the battery-grade properties. The results suggested that the fabricated electrode consumes an excellent potential as a high energy source for hybrid energy storage devices. [ABSTRACT FROM AUTHOR]

A shift to alternate energy sources is needed at the present time to address rising environmental concerns. The current research work aims to use a chemical‐free and green route to synthesize nanocomposite for their application as an electrode in the generation as well as storage of energy. Subsequently, the green synthesis of Bi2O3‐Sb2O3 nanocomposite was carried out using the leaf extract of Amaranthus viridis. The synthesized nanocomposite revealed a well‐arranged pattern of spherical nanoparticles with a crystal size of 29.43 nm and a band gap value of 2.5 eV. The hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) potentials of Bi2O3‐Sb2O3 were studied through linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS), whereas the energy storage studies were performed using cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) techniques. The synthesized nanomaterial showed promising results for HER with an overpotential value of 205 mV as compared with OER, where an overpotential value of 450 mV was observed. However, excellent cyclic stability was witnessed for both reactions up to 1000 cycles. CV studies revealed an outstanding capacitance value of 348 F/g at a scan rate of 2 mV/s, whereas a specific capacitance of 269.5 F/g at a current density of 0.5 A/g was observed using GCD. The 15 h of electrode stability further endorsed the potential of synthesized material for energy‐based applications. [ABSTRACT FROM AUTHOR]

This research aims to demonstrate that a one-of-a-kind microencapsulated bio-based PCM may be utilized in the passive collection of solar energy in buildings. The research makes use of a PCM with thermal properties within the comfort zone but is also able to track the performance of solar photovoltaic panels. This allows the research to be more accurate. Because of this, the research can produce outcomes that are more accurate. After finishing the step before this one, the next thing that needs to be done is creating novel composite concrete panels. This step follows the completion of the phase before it. The outcomes of the mechanical and thermal tests served as the basis for determining the best composition of the concrete mix that should be used for making this panel. The method concludes with the construction of a test structure using composite walls as the primary building material. [ABSTRACT FROM AUTHOR]

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]