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The integration of solar photovoltaic (SPV) systems with modular multiport converters (MMPC) enables efficient energy conversion and distribution, enhancing the overall performance and reliability of renewable energy systems (RES). However, the complexity of the control algorithms and potential issues related to the dynamic response can pose challenges in achieving optimal performance and stability in varying operating conditions. This paper proposes a hybrid method for integrating SPV systems with MMPC to achieve efficient power management in modern renewable energy grids. The proposed hybrid method is the combined execution of the Osprey Optimization Algorithm (OOA) and Relational Bi-level Aggregation Graph Convolutional Network (RBAGCN). Hence it is named as OOA-RBAGCN technique. The aim is to ensure optimal power transfer, minimize total harmonic distortion (THD), maintain voltage stability under dynamic operating conditions, and ultimately improve the overall energy efficiency, reliability, and performance of SPV-based RES within smart grid applications. The OOA is used to optimize the control parameter of the proportional-integral (PI) controller. The RBAGCN is used to predict these optimized parameters. By then, the proposed approach is used on the MATLAB platform and compared with other approaches such as Starling Murmuration Optimization (SMO), Dung Beetle Optimizer (DBO), Improved Harris Hawks Optimization (IHHO), Grey Wolf Optimization (GWO), and Particle Swarm Optimization (PSO). The proposed method achieves a high efficiency of 98.1%, and a reduced THD of 2.9% significantly surpassing all existing methods.

The latent heat storage system is considered the most promising technology in thermal energy storage (TES) because of its many advantages. This technique uses phase change material (PCM) as a TES medium. However, the low thermal conductivity (TC) of PCM is the major drawback of the system. Previous studies have shown that the addition of nanomaterials to PCM generally increases its TC. On the other hand, researchers tend to study the possibility of using enhanced PCM to cool solar cells. In fact, raising the solar cell’s operating temperature negatively impacts its efficiency. This problem is considered one of the biggest problems in solar energy systems, and researchers are still working to solve it. This paper focused on the possibility of enhancing the TC of paraffin by adding different shapes of silver nanomaterials to it (silver nanoparticles, silver nanowires and nanohybrid with silver nanoparticles and silver nanowires). Nanomaterials were added at volume fractions of 0.5% and 1%. Then, the study examined the ability to use this improved material to reduce the temperature of solar cells. We used the “Solidworks” program to create a 3D system, and then we used the “Ansys Fluent” software to simulate five cases; PV without PCM, PV with PCM, PV with PCM enhanced by nanoparticles, PV with PCM enhanced by nanowires, PV with PCM enhanced by nanohybrid (a mixture of nanoparticles and nanowires). The results show that using PCM enhanced by nanowire at a volume fraction of 0.5% gave the best results in decreasing the temperature of PV. The average temperature of PV declined by 14.9${}^{\circ }$. In addition, the efficiency of PV rose by about 7.6%. Followed by using PCM enhanced by nanoparticles at a volume fraction of 1%. The average temperature of PV declined by 12.9${}^{\circ }$. Moreover, the efficiency of PV rose by about 6.6%.

First-principles calculations of the structural, electronic, optical and thermal properties of chalcopyrite CuXTe₂ (X=Al, Ga, In) have been performed within density functional theory using the full-potential linearized augmented plane wave (FP-LAPW) method, by employing for the exchange and correlation potential the approximations WC-GGA and mBJ-GGA. The effect of X cations replacement on the structural, electronic band structure, density of states and optical properties were highlighted and explained. Our results are in good agreement with the previous theoretical and experimental data. As far as we know, for the first time we find the effects of temperature and pressure on thermal parameters of CuAlTe₂ and CuGaTe₂ compounds. Thermal properties are very useful for optimizing crystal growth, and predict photovoltaic applications on extreme thermodynamic conditions.

In this study, indium tin oxide (ITO) was deposited onto sapphire and low resistive p-Si substrates using pulsed laser deposition (PLD) technique. The optical energy gap of ITO deposited on the sapphire substrate was 3.7 eV at room temperature. Photoluminescence (PL) of ITO shows an emission of broad peak at 524 nm. Photovoltaic (PV) characteristics of the n-ITO/p-Si heterojunction are examined and showed conversion efficiency $(\eta )$ of 1.8%. The open circuit voltage $(V_{\mathrm{\text{OC}}})$ for this cell was 0.49 V while the short circuit current density $(J_{\mathrm{\text{SC}}})$ was 17.4 mA/cm². The fill factor of this cell was 22%. The ideality factor of ITO/Si heterojunction is about 3.1. The barrier height ${\mathrm{\Phi }}_B$ of the heterojunction was determined from I–V characteristics and was 0.83 eV. The responsivity of the heterojunction was measured and the maximum value of responsivity was 0.5 A/W without bias voltage. The minority carrier lifetime of the solar was measured using open circuit voltage decay (OCVD) method and found to be 227 $\mu$s.

Perovskite solar cells (PSCs) without hole transport layer (HTL) based on organic and inorganic metal halide perovskite have received vast consideration in recent years. For predigestion of device structure and construction process, the exclusion of the HTL is a marvelous way. By detaching the HTL part of the devices, we could reduce the cost and complexity of the structures. Currently, a novel 2D material named Ti₃C₂ MXene with high electron mobility, excellent metallic conductivity and functionalized surface groups applied for tuning the energy offsets has been reported to be added in the perovskite absorber layer, leading to a remarkable power conversion efficiency (PCE) improvement. In this work, the role of MXenes in controlling the work function of the involved layers to modify the band alignment towards better performance of the cells is explained. Two HTL free structures of FTO/mTiO₂/cTiO₂/MAPbI₃/Spiro-OMeTAD/Au named as HFRC, and FTO/mTiO₂+MXene/cTiO₂+MXene/MXene/MAPbI₃+MXene/Spiro-OMeTAD/Au named as HFMC were simulated by SCAPS-1D software to study the response of the photovoltaic devices and obtain the highest possible efficiency considering the physics behind. To the best of our knowledge, this is the first time such structures and the results of the current simulation are studied that may be used as a guideline for other practical purposes. We present a modeling procedure that optimizes the thickness of the involved layers and specifies the optimum level of the doping concentration. We also show that by optimizing the work function of the back contact, the device performance witnesses a significant improvement, proving the considerable role of the back contact in these cells. The simulated HTL-free devices illustrate attainably PCEs of about 20.32% and 21.04% for the cells without and with MXene, under AM 1.5G illumination and absorption up to 760 (nm).

Amorphous carbon nitride (a-C:N) thin films are deposited by pulsed laser deposition technique at room temperature using a camphoric carbon target with different nitrogen partial pressures in the range from 0.1 to 800 mTorr. The room temperature conductivity (σ_RT) is found to increase with N incorporation, which may be due to the lattice vibrations leading to the scattering of the charge carriers by the N atoms and the more amorphous nature of the carbon films. Study of activation energy reveals that the Fermi level of the a-C:N film moves from the valence band to near the conduction band edge through the midgap. The current–voltage photovoltaic characteristics of a-C:N/p-Si cells under 1 sun air-mass 1.5 (AM 1.5) illumination condition (100 mW/cm², 25°C) are improved up to 30 mTorr and deteriorate thereupon. The maximum of open-circuit voltage (V_oc) and short-circuit current density (J_sc) for the cells are observed to be approximately 292 mV and 9.02 mA/cm², respectively. The highest energy conversion efficiency (η) and fill factor (FF) were found to be approximately 1.47% and 56%, respectively.

Hydrogenated amorphous carbon films (a-C:H) were deposited on p-type silicon (a-C:H/p-Si) and quartz substrates by excimer laser at room temperature using mixture ratios 1 to 9 and 3 to 7 of camphor to graphite by weight percentages. The presence of hydrogen in the a-C:H films has been confirmed by Fourier transform infrared spectroscopy (FTIR) measurements. The structure and optical properties of a-C:H films were respectively investigated by Raman scattering and UV-visible spectroscopy. The increase of sp³ sites in the a-C:H films has also been confirmed by the Raman spectra spectroscopy analysis. The increase of the optical band gap with higher camphor percentage in the target was believed to be due to the increase of the sp³ hybrid forms of carbon arising from camphor incorporation. The formation of a heterojunction between the a-C:H film and Si substrate was confirmed by current–voltage (I–V) measurement. The structure of a-C:H/p-Si cells deposited using mixture ratios 1 to 9 of camphor to graphite by weight percentages showed better photovoltaic characteristics with an open-circuit voltage of 400 mV and short-circuit current density of about 15 mA/cm² under AM 1.5 (100 mW/cm² at room temperature) illumination. The energy conversion efficiency and fill factor were found to be approximately 2.1% and 0.38, respectively. The carbon layer contributed to the energy conversion efficiency in the lower wavelength region has been proved by the quantum efficiency measurement.

In this work, numerical calculations and simulation based on Transfer Matrix Method have been presented to investigate a model solar cell structure. New four-layered structure containing different types of semiconductor has been presented, analyzed and discussed. The average reflectance and average transmittance in the visible light are derived and plotted versus the operating wavelength at different physical parameters. The obtained results show that the proposed structure is a promising candidate to be used for designing future solar cell structures.

We have investigated the impact of three different soiling types (dust, leaf, rainfall) on the current–voltage and power–voltage characteristics of a solar panel located at different locations. The current and power losses were measured regularly for 50 days (10-day interval). The soiling ratio was calculated to be a reliable parameter for soiling impact assessment. The source of current and power losses due to soiling was rooted by measuring the transmittance loss and panel surface temperature increase, external quantum efficiency and electroluminescence spectrum recorded for the range of 950–1300 nm. The results confirm leaves as the most detrimental soling type with 38% power loss compared to dust and raindrop and the lowest loss in current density and power was related to raindrop (29%). This is confirmed by the significant decrease in the soiling ratio of the leaf-soiled panels from 0.9 to $<0.1$ in 50 days. Electroluminescence spectra confirm the critical impact of leaf-soiling on defect generation in the materials and a reduced photocurrent generation. Leaf could reduce the current and power of the panel from 14A to 12A and from 190W to 100W, respectively.

With the virtual synchronous generator (VSG) technology gradually becoming an emerging technology for new energy consumption, its introduction has solved the problems of weak support and weak anti-interference of traditional new energy stations. However, the practice shows that the grid-connected characteristics of VSG limit its large-scale utilization, and there is little research on the interaction between VSG and a multi-machine system. In this paper, small signal models and time domain simulation models of each link of a photovoltaic(PV) power station with the PV virtual synchronous generator (PV-VSG) are first conducted, and then the influence of the grid-connected PV power station with the PV-VSG on the low-frequency oscillation of power system and its interaction mechanism with the multi-machine system are qualitatively obtained based on the small signal analysis method and prony analysis method from two dimensions of frequency domain and time domain, respectively. The analysis and simulation show that the PV power station based on VSG technology affects the dynamic characteristics of the system by changing the electromagnetic torque of each synchronous generator. Unreasonable operating conditions and parameter settings will aggravate the phenomenon of low-frequency oscillation of the system. Before the grid connection of PV power station, the operating parameters shall be reasonably set to ensure their safe and stable grid connection.

Dynamic voltage instability is one of the major issues faced by grid-connected renewable energy systems due to fluctuations in the generation and sudden variation in the loads. The primary objective of this paper is to propose a method for constant power consumption from the grid to maintain a stable DC-link voltage during peak and nonpeak hours. It can be achieved by implementing an optimized active power management (OAPM) scheme between the photovoltaic (PV) and the grid by enabling a battery energy storage system (BESS). The intelligent constant power balance (ICPB) algorithm and detailed control strategies for dual active bridge (DAB) isolated DC–DC converter and grid-connected voltage source inverter (VSI) are discussed in this paper. Moreover, the high-gain step-up DC–DC converter (HSDC) is utilized to perform maximum power point tracking (MPPT) operation and to meet the required DC-link voltage. The accuracy of power transmission of DAB gets improved by imposing a curve-fitting interpolation (CFI) approach, thereby maintaining a constant DC-link voltage. Furthermore, an instantaneous sinusoidal current control (ISCC) scheme assures the feeding of active power with better power quality. The measured results are obtained and verified under different dynamic conditions of load and generation. Based on the validation, we conclude that the proposed OAPM scheme is most suitable for grid-connected renewable energy systems in the rural electrified microgrid.

This paper introduces a Multi-Level Cascade Inverter (MLI) based on Enhanced Quasi-Z Source Inverter (MQZSI) to connect photovoltaic (PV) systems based on the proposed method. Usually the interface among PV power supply and load is completed with MQZS-CMLI. In this paper, the proposed control scheme is comprehensive implementation of Recalling Enhanced Recurrent Neural Network (RERNN) and Quasi-Opposite Chemical Reaction Optimization (QOCRO) named as RENCO. The main objective of proposed method is to decide the efficiency of the PV system by the maximal power extraction. Here, MQZS-CMLI’s modeling design contains suitable number of components, other than their capacitors and semiconductors comply with low-voltage stress. It is improved for providing that maximum power of the PV power generation system. At first, the goal function is described according to the parameters and limitations of controller (like voltage, current, power, modulation index, so on). These parameters apply to recommend RENCO technology input. The proposed RENCO technology improves voltage distribution, power transmission, and minimizes power fluctuations while sharing power with load. The proposed MPPT-based technology ensures that the maximum power is provided to load. The proposed method adjust the duty cycle of MQZS-CMLI and reduces the modulation load. Finally, the proposed technology is executed on the MATLAB/Simulink platform, and its output efficiency is compared to existing systems under dissimilar load circumstances.

Forecasting solar radiation for a given region is an emerging field of study. It will help to identify the places for installing large-scale photovoltaic-systems, designing energy-efficient buildings and energy estimation. The different machine learning kernel-based approaches for prediction problems uses either a local or global kernel. These models can provide either strong training capability or good generalization performance. In this paper, a new hybrid kernel is proposed using the combination of a local and global kernel. A novel algorithm Hybrid Kernel-based Extreme Learning Machine is proposed for predictive modelling of Incident Solar Radiation (ISR) time series using new hybrid kernel. The proposed algorithm uses the surface, atmospheric, cloud properties obtained from the MODIS instrument and observed ISR at time t – 1 to predict ISR at time t. This study is conducted for 41 diverse sites of Australia for the period of 2012–2015. Further, the proposed model is experimented with other time series datasets to prove its efficacy. It is shown that the proposed methodology outperforms five other benchmarking methods in terms of MAE and Willmott’s Index (WI). Therefore, the suggested approach can be used for modelling solar energy at a national scale using remotely-sensed satellite footprints.

In this manuscript, a proficient control strategy-based improved Quasi-Z-Source Cascaded Multilevel Inverter (QZS-CMI) topology for interfacing photovoltaic (PV) system is proposed. The control strategy is joint execution of both recalling-enhanced recurrent neural network (RERNN) and Shell Game Optimization (SGO), therefore it is called RERNN-SGO technique. The major intention of proposed system determined the photovoltaic system efficiency and maximize the power extraction. The interface among load and PV dc source is to accomplish by the QZSI. At first, the objective function is determined depending on the control constraint and parameters, like current, voltage, modulation index, power. These parameters are utilized to propose RERNN-SGO method. The RERNN-SGO method is used to improve the power delivery, voltage profile and minimum power oscillation for power distribution with load. The maximal power delivered the load is to ensure the artificial intelligence (AI) strategy with the help of maximal power point tracking (MPPT). To regulate shoot through duty ratio and modulation load, the proposed AI method is used. The proposed system is inspired on MATLAB/Simulink site, and then efficiency is related with existing systems under various load conditions. The efficiency of proposed system in Case 1 and Case 2 is 87.363% and 85.3904%.

This paper reports on the successful deposition of phosphorus (P)-doped n-type (p-C:P) carbon (C) films, and fabrication of n-C:P/p-Si cells by pulsed laser deposition (PLD) using graphite target at room temperature. The cells performances have been given in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100mW/cm², 25°C). The n-C:P/p-Si cell fabricated using a target with the amount of P by 7 weight percentages (Pwt%) shows the highest energy conversion efficiency η = 1.14% and fill factor FF = 41%. The quantum efficiency (QE) of the n-C:P/p-Si cells are observed to improve with Pwt%. The dependence of P content on the electrical and optical properties of the deposited films and the photovoltaic characteristics of the n-C:P/p-Si heterojunction solar cell are discussed.

Highly (101)-oriented p-Ag₂O thin film with high electrical resistivity was grown by rapid thermal oxidation (RTO) on clean monocrystalline p-type Si without any post-deposition annealing. From optical transmittance and absorptance data, the direct optical band gap was found to be 1.46 eV. The electrical and photovoltaic properties of Ag₂O/Si isotype heterojunction were examined in the absence of any buffer layer. Ideality factor of heterojunction was found to be 3.9. Photoresponce result revealed that there are two peaks located at 750 nm and 900 nm.

The successful deposition of boron (B)-doped p-type (p-C:B) and phosphorous (P)-doped n-type (n-C:P) carbon (C) films, and fabrication of p-C:B on silicon (Si) substrate (p-C:B/n-Si) and n-C:P/p-Si cells by the technique of pulsed laser deposition (PLD) using graphite target is reported. The cells' performances are represented in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100 mW/cm², 25°C). The open circuit voltage (V_oc) and short circuit current density (J_sc) for p-C:B/n-Si are observed to vary from 230–250 mV and 1.5–2.2 mA/cm², respectively, and to vary from 215–265 mV and 7.5–10.5 mA/cm², respectively, for n-C:P/p-Si cells. The p-C:B/n-Si cell fabricated using the target with the amount of B by 3 Bwt% shows highest energy conversion efficiency, η = 0.20%, and fill factor, FF = 45%, while, the n-C:P/p-Si cell with the amount of P by 7 Pwt% shows highest energy conversion efficiency, η = 1.14%, and fill factor, FF = 41%. The quantum efficiencies (QE) of the p-C:B/n-Si and n-C:P/p-Si cells are observed to improve with Bwt% and Pwt%, respectively. The contributions of QE are suggested to be due to photon absorption by carbon layer in the lower wavelength region (below 750 nm) and Si substrates in the higher wavelength region. The dependence of B and P content on the electrical and optical properties of the deposited films, and the photovoltaic characteristics of the respective p-C:B/n-Si and n-C:P/p-Si heterojunction photovoltaic cells, are discussed.

Surface photovoltage of semiconductors depend strongly on their electronic structures, in particular, their Fermi energy level. This offers a possibility to characterize photoelectronic behavior using the Kelvin probe structure by measurements of work function (WF). In this paper, ZnO films were prepared using the CVD method and their microstructures and morphology were characterized using the XRD and SEM. Furthermore, photovoltage evolution and WF of selected ZnO samples were measured using a scanning Kelvin probe (SKP) system. It is found that the surface photovoltage and its time-resolved evolution process as well as the energy level structure of ZnO films can be correlated to WF very well. The present study therefore provides a simple and practical methodology for the characterization of photovoltaic behavior of semiconductor films.

Dye sensitized solar cells (DSSCs) provide promisingly, organic–inorganic, clean hybrid, cost effective and efficient molecular solar cell devices. Due to their distinct and multifunctional qualities, zinc oxide (ZnO) nanostructures are promising materials used to create photoanodes for DSSCs due to the availability of larger surface area than bulk sheet substance, effectual light-dispersing centers, and when mixed with titanium dioxide they produce a core–shell formation that diminishes the coalition rate and provide direct charge. Moreover, ZnO thin sheets have been broadly observed due of its potential application in various fields i.e. piezoelectric, photovoltaic, pyroelectric and optoelectronic utilization. This review studies the recent advances in the fabrication of zinc oxide-based photovoltaics; synthesis of ZnO nanostructures with variable morphologies including thin sheets, nanotubes, nanorods, nanoflowers, nanofibers and factors that control the growth and morphologies of these nanospecies and part of crystallographic planes for the fabrication of various zinc oxide nanoshapes. In the next part of this paper, numerous fabrication routes — doped and undoped ZnO thin films — are discussed and different parameters of photovoltaics are investigated, e.g. efficiency pre and post annealing temperatures, fill factors spinning speed and coating time, additives, nature of precursor which impacts on morphological and optical parameters of these sheets. In short, this review is dedicated to the ZnO photoanode, its properties, issues related to ZnO photoanode, various improvement approaches, fabrication methods successfully trialled so far followed by market potential of the DSSC technology, conclusion and recommendations

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