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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]

Abstract: This study focused on the characterization and optimization of a Zn(S,O,OH) thin film via chemical bath deposition (CBD) on a Cu(In,Ga)Se2 (CIGS) film in order to obtain a reproducible and high-quality Cd-free buffer layer. High-resolution images of the actual film growth during the CBD process were observed to deeply understand the growth conditions for a uniform and pinhole-free Zn(S,O,OH) film on the CIGS film. The homogeneous precipitation of Zn(S,O,OH) was suppressed through the complexation reaction in the solution, and the heterogeneous precipitation of Zn(S,O,OH) was activated on the CIGS film by increasing the NH3 concentration. At NH3 concentration of 7M, the Zn(S,O,OH) film grown on the CIGS film completely covered the CIGS surface via the heterogeneous precipitation of Zn(S,O,OH). However, it contained many pinholes. The pinholes were eliminated by suppressing the formation of the Zn(OH)2 precipitates at a lower temperature (73°C). At the optimized conditions of the CBD process, the buffer film grown on the CIGS film contained a large amount of oxygen in the form of Zn–O and Zn–OH bonds. By annealing the Zn(S,O,OH) film, the content of the Zn–OH bond decreased through dehydration and that of the Zn–O bond increased. The J SC of the cell performance was greatly improved by annealing the Zn(S,O,OH) film and a conversion efficiency of 14.2% with V OC=0.62V, J SC=35.1mA/cm2, and FF= 65.1 was achieved. [Copyright &y& Elsevier]

Copper metal is third most abundant trace element in human body. Determination of Cu (II) ions is a burning topic in field of environment protection and food safety because of its significant impact on ecosystem. In this study, 2,6-pyridine dicarboxylic acid (PDA) has been explored as "turn-off" florescent probe for florescent detection of Cu (II) ions. This sensor showed highly selective complexing ability towards Cu (II) ions. Addition of aqueous solution of Cu (II) ions remarkably quenched the fluorescence intensity of PDA while, on contrary, there was no any prominent fluorescence quenching interference on addition of various metal ions. The binding mode of PDA and Cu (II) ions was determined as stoichiometry of 1:1 and it was further confirmed by single crystal XRD analysis. Mechanisms of static and dynamic quenching were confirmed by stern-volmer plot. Limit of detection (LOD) and limit of quantification (LOQ) for Cu (II) ions was calculated as 3.6 µM and 1.23 µM respectively, which is far below the acceptable value (31.5µM) according to the World Health Organization. The use of the sensor for detection of Cu (II) ions in real samples in aqueous media was also performed., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Wind is one of the most widely used renewable energy sources due to its cost-effectiveness, power requirements, operation, and performance. There are many challenges in wind turbines, such as wind fluctuation, pitch control, and generator speed control. When the wind speed exceeds its rated value, the pitch angle controller limits the generator output power to its rated value. In this research work, several soft computing techniques have been implemented for pitch control of variable-speed wind turbine. The data is collected for the National Renewable Energy Laboratory offshore 5 MW baseline wind turbine. Wind speed, tip speed ratio, and power coefficient are taken as inputs, and pitch angle as output. Machine learning and artificial intelligence-based techniques such as recurrent neural networks (RNNs), adaptive neuro-fuzzy inference system (ANFIS), multilayer perceptron feed-forward neural network (MLPFFNN), and fuzzy logic controller (FLC) are implemented on MATLAB, and their results are evaluated in terms of mean square error (MSE) and root mean square error (RMSE). The controllers have been implemented in MATLAB/Simulink to schedule the wind turbine blade pitch angle and keep the output power stable at the rated value. The experimental results show that RNN provided the best results for 15 neurons in hidden layers and 1000 epochs with MSE of 3.28e-11 and RMSE of 5.54e-06, followed by MLPFFNN with MSE of 2.17e-10 and RMSE of 1.56e-05, ANFIS with MSE of 8.5e-05 and RMSE of 9.22e-03, and FLC with MSE of 6.25e-04 and RMSE of 0.025. The proposed scheme is more reliable and robust and can be easily implemented on a physical setup by using interfacing cards such as dSPACE, NI cards, and data acquisition cards., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Efficient energy storage and conversion is crucial for a sustainable society. Battery-supercapacitor hybrid energy storage devices offer a promising solution, bridging the gap between traditional batteries and supercapacitors. In this regard, metal-organic frameworks (MOFs) have emerged as the most versatile functional compounds owing to their captivating structural features, unique properties, and extensive diversity of applications in energy storage. MOF properties are governed by the structure and topological characteristics, which are influenced by the types of ligands and metal nodes. Herein, MOFs based on pyridine 3,5-dicarboxylate (PYDC) ligand in combination with copper and cobalt are electrochemically analyzed. Owing to the promising initial characterization of Cu-PYDC-MOF, a battery supercapacitor hybrid device was fabricated, comprising Cu-PYDC-MOF and activated carbon (AC) electrodes. The device showcased energy and power density of 17 W h kg -1 and 2550 W kg -1 , respectively. Dunn's model was employed to gain deeper insights into the capacitive and diffusive contributions of the device. With their performance and versatility, the PYDC-based MOFs stand at the forefront of energy technology, ready to power a brighter future for upcoming generations., Competing Interests: There are no conflict to declare., (This journal is © The Royal Society of Chemistry.)

In digital era, energy efficient building remains a hot research topic because of increasing concern regarding their environmental impact and energy consumption. Designing a suitable energy efficient building based on their layout namely overall areas, distribution of the glazing areas, orientation, height, and relative compactness. Such components directly impact the heating load (HL) and cooling load (CL) of residential buildings. A precise predicting of load facilitates effective management of energy consumption and improves the quality of life. Lately, several studies have been implemented to predict the CL and HL. The most significant and challenging parts of predictive are defining the effective input parameter and developing a higher accuracy predictive model. The accuracy of predictive model based on machine learning algorithm must be enhanced by hybrid model. With this motivation, this article introduces an Improved Harris Hawks Optimization with Hybrid Deep Learning Based Heating and Cooling Load Prediction (IHHOHDL-HCLP) model on Residential Buildings. The major aim of the IHHOHDL-HCLP model is to determine the CL and HL to accomplish effective energy utilization. To accomplish this, the IHHOHDL-HCLP primarily pre-processes the raw data in two levels namely min-max normalization and polynomial equation. In addition, the HDL model involves convolutional neural network (CNN) along with long short-term memory (LSTM) and bidirectional long short-term memory (BiLSTM) for HL and CL prediction process. Finally, the IHHO technique was applied for fine-tuning the hyperparameters related to the DL model. The IHHOHDL-HCLP model has demonstrated maximum prediction results with low RMSE values of 0.00874 and 0.00821, respectively, when applied to HL and CL, respectively. The experimental result analysis of the IHHOHDL-HCLP model demonstrates the better performance of the IHHOHDL-HCLP model over other DL models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The electronic band structure at the Zn(1-x)Mg(x)O/Cu(In(0.7)Ga(0.3))Se(2) interface was investigated for its potential application in Cd-free Cu(In,Ga)Se(2) thin film solar cells. Zn(1-x)Mg(x)O thin films with various Mg contents were grown by atomic layer deposition on Cu(In(0.7)Ga(0.3))Se(2) absorbers, which were deposited by the co-evaporation of Cu, In, Ga, and Se elemental sources. The electron emissions from the valence band and core levels were measured by a depth profile technique using X-ray and ultraviolet photoelectron spectroscopy. The valence band maximum positions are around 3.17 eV for both Zn(0.9)Mg(0.1)O and Zn(0.8)Mg(0.2)O films, while the valence band maximum value for CIGS is 0.48 eV. As a result, the valence band offset value between the bulk Zn(1-x)Mg(x)O (x = 0.1 and x = 0.2) region and the bulk CIGS region was 2.69 eV. The valence band offset value at the Zn(1-x)Mg(x)O/CIGS interface was found to be 2.55 eV after considering a small band bending in the interface region. The bandgap energy of Zn(1-x)Mg(x)O films increased from 3.25 to 3.76 eV as the Mg content increased from 0% to 25%. The combination of the valence band offset values and the bandgap energy of Zn(1-x)Mg(x)O films results in the flat (0 eV) and cliff (-0.23 eV) conduction band alignments at the Zn(0.8)Mg(0.2)O/Cu(In(0.7)Ga(0.3))Se(2) and Zn(0.9)Mg(0.1)O/Cu(In(0.7)Ga(0.3))Se(2) interfaces, respectively. The experimental results suggest that the bandgap energy of Zn(1-x)Mg(x)O films is the main factor that determines the conduction band offset at the Zn(1-x)Mg(x)O/Cu(In(0.7)Ga(0.3))Se(2) interface. Based on these results, we conclude that a Zn(1-x)Mg(x)O film with a relatively high bandgap energy is necessary to create a suitable conduction band offset at the Zn(1-x)Mg(x)O/CIGS interface to obtain a robust heterojunction. Also, ALD Zn(1-x)Mg(x)O films can be considered as a promising alternative buffer material to replace the toxic CdS for environmental safety.