Assessing the Environmental Benefits of Extending the Service Lifetime of Solar Photovoltaic Modules.

Requiring no fuel for generation and negligible material/energy for operation and maintenance, photovoltaic (PV) systems have environmental impacts mostly due to the production of modules and the commissioning of power plants. Thus, extending the service lifetime of these systems from 30 to 40 years through an enhanced lamination process for module production potentially reduces environmental impacts per unit energy generated. Life cycle assessment is employed to evaluate the environmental impacts under scenarios for resource utilizations for the new lamination process, operation and maintenance requirements in the extended service lifetime, and degradation rates of the devised modules. Extending the service lifetime significantly reduces environmental impacts across categories, with a 21-27% reduction in global warming potential on the pessimistic and optimistic ends. At least 20% impact reduction is achieved in most impact categories, even under a pessimistic scenario. Considering uncertainty models in the life cycle inventories, samples are generated for scenarios via Monte Carlo simulation, and with significant improvements with large effects in most environmental impact categories, deterministic impact comparisons are supported by ANOVA and Tukey tests. Production strategies for more durable and reliable PV modules have a significant potential in contributing to global sustainability efforts.

Experimental analysis of dust's impact on solar photovoltaic system efficiency in arid environments: a case study in Southern Algeria.

The purpose of this study is to explore the effects of accumulated dust and weather conditions on the energy generated by solar photovoltaic panels in Ouargla, Algeria, between May 3 and August 3, 2023. For this experiment, two monocrystalline panels with a power output of 390 W manufactured by Zergoune Green Energy Company, as well as data-logging equipment, were used. The first panel was perfectly cleaned before starting every test and the second panel remained uncleaned. On day 90, the cleaned panel maintained an average power of 193 W, while the dusty panel exhibited a lower average power of 139 W. The greatest average reduction in efficiency, approximately 36.32%, occurred after 3 months of exposure to weather conditions. The scanning electron microscope (SEM) analysis demonstrates the existence of microscopic dust particles which prevent part of solar radiation away instead of being absorbed by the photovoltaic cells, leading to a drop in the efficiency of the PV module. The primary chemical elements found in dust are oxygen, silicon, aluminum, and magnesium.

Design of a Portable Low-Cost I-V Curve Tracer for On-Line and In Situ Inspection of PV Modules.

Identifying underperforming photovoltaic (PV) modules is crucial to ensure optimal energy production and financial returns, as well as preventing potential safety hazards in case of severe damage. To this aim, current-voltage (I-V) curve tracing can be employed as in situ monitoring technique for the early detection of faults. In this paper, we introduce a novel low-cost, microcontroller-based I-V tracer for the diagnosis of individual PV modules. The tool features a unique power conditioning circuit, facilitating accurate data acquisition under static conditions as well as the even distribution of the measured points along the I-V curve. A specific active disconnecting circuit enables in situ and on-line measurement without interrupting the string power generation. The designed prototype is used to characterize a set of PV modules under real operating conditions. The measured I-V curves exhibit expected trends, with the measured data closely matching theoretical values and an estimated mean relative error less than 3%.

An adaptable method for efficient modeling of photovoltaic generators' performance based on the double-diode model.

The aim of this study is to establish an effective modeling technique for simulating the performance of photovoltaic modules by calculating their electrical parameters based on the two-diode model. The suggested methodology involves reducing the scope of the study from seven unknown parameters to only three, and that without resorting to any approximations. The first four parameters are calculated analytically based on the data representing the crucial positions on the current-voltage graph and using a new expression of the fill-factor derived from the two-diode equivalent circuit. The remaining parameters are established numerically based on a simple iterative technique adaptable with two sites of data availability. The photovoltaic modeling begins by utilizing the values of key-points. Subsequently, to ensure the proposed approach's adaptability to various scenarios of available information about PV generators, it is invested and applied for an optimization process. The accuracy is evaluated for diverse types of photovoltaic modules, and the results are weighed against widely reviewed numerical methods and evolutionary optimization algorithms in the literature. As a result, the new method demonstrates superior performance, yielding the smallest values for the utilized statistical indicators and reducing compilation time. These findings underscore its flexibility and high efficiency in simulating photovoltaic devices.

Mechanical Analysis of the Quasi-Static and Dynamic Composite Action in PV Modules with Viscoelastic Encapsulant.

The mechanical analysis of photovoltaics and building integrated photovoltaics is a key step for their optimal design and certification, and requires careful consideration, alongside solar power, durability and functionality issues. The solar cells are encapsulated in thin interlayers that are usually composed of a viscoelastic Ethylene-Vinyl Acetate compound, and protected by thin glass and/or plastic layers. This paper investigates the out-of-plane bending response of a full-scale commercial PV module and focuses attention on the shear bonding efficiency of the thin encapsulant for quasi-static and dynamic mechanical considerations. The parametric analytical analysis, carried out in this study for a laminated glass plate, highlights the possible consequences of the viscoelastic shear coupling on the cross-section load-bearing demand in the covers. As a direct effect of severe operational conditions (i.e., ageing, non-uniform/cyclic thermal gradients, humidity, extreme mechanical/thermal loads, etc.) the shear rigidity and adhesion of these films can suffer from repeated/progressive modification and even degradation, and thus induce major stress and deflection effects in the out-of-plane mechanical response of the PV module components. The minimum shear bond efficiency required to prevent mechanical issues is calculated for various configurations of technical interest. Accordingly, it is shown how the quasi-static and dynamic mechanical performance of the system modifies as a function of a more rigid or weak shear coupling.

Development of a Recycling Process and Characterization of EVA, PVDF, and PET Polymers from End-of-Life PV Modules.

Photovoltaic (PV) modules are highly efficient power generators associated with solar energy. The rapid growth of the PV industry will lead to a sharp increase in the waste generated from PV panels. However, electro-waste can be successfully used as a source of secondary materials. In this study, a unique procedure for recycling PV modules was developed. In the first stage, the aluminum frame and junction box, 18wt%. and 1wt%. of the module, respectively, were removed. The following stage was crucial, involving a mechanical-thermal method to remove the glass, which accounts for 70wt%. As a result, only 11wt%. of the initial mass of the PV was subjected to the next stage of chemical delamination, which reduced the amount of solvent used. Toluene was used to swell the ethylene vinyl acetate, EVA, and allow for the separation of the PV module. The effects of temperature and ultrasound on separation time were investigated. After the separation of silicon cells, metal ribbons, EVA, and the backsheet were obtained. The purity of the polymers was determined by FTIR and elemental analysis. Thermal properties were measured using DSC calorimetry to determine the basic parameters of the material.

Effect of dust accumulation on the performance of photovoltaic modules for different climate regions.

In the past decade, solar photovoltaic (PV) modules have emerged as promising energy sources worldwide. The only limitation associated with PV modules is the efficiency with which they can generate electricity. The dust is the prime ingredient whose accumulation on the surface of PV impacts negatively over its efficiency at a greater rate. This research aims to explore the effects of dust accumulation on the energy output and operating temperature of polycrystalline silicon PV panels situated in two different climatic regions of Pakistan, i.e., Islamabad and Bahawalpur. In both the regions, one PV module is kept in ambient environment for six weeks to allow dust to deposit over its surface and perform experimental analysis with one clean module as reference for performance comparison. After six weeks of atmospheric exposure, dusty modules displayed significantly smaller efficiency as a function of different dust densities in the two regions. Dust samples from both cities are collected and analyzed to evaluate their structural attributes and composition. The PV module in Islamabad region had a dust layer over its surface with a density of 6.388 g/m2 and its efficiency was reduced by 15.08%. In Bahawalpur region, the dust density was observed to be 10.254 g/m2 which caused the output power to be slashed by 25.42%. Temperature analysis of modules shows that dust increases their temperatures which is also a quantity responsible for lower PV power generation with same amount of irradiance. The research findings are crucial for determining and predicting PV power degradation in two different atmospheres and determining the schedule of cleaning cycle.

Experimental investigation for enhancing PV module energy performance using phase change material.

The aim of this study is to enhance the energy performance of PV modules in the Ghardaïa region of Algeria by using an additive PCM (CaCl2·6H2O). The experimental configuration is set up to provide efficient cooling by reducing the operating temperature of the PV module's rear surface. The PV module operating temperature, output power, and electrical efficiency for both cases with PCM and without PCM have been plotted and analyzed. In the experiments, it was found that using phase change materials improves the energy performance and output power of PV modules by reducing their operating temperature. In comparison to the PV-PCM module without PCM, the average operating temperature is reduced by up to 20 °C. Besides, PV modules with PCM have an average power of 46.11% higher than PV modules without PCM. The electrical efficiency of PV module with PCM is on average 6% higher than the configuration without PCM.

Quantitative impact assessment of temperature on the economics of a rooftop solar photovoltaic system.

This paper analyzes the economics of a grid-interactive rooftop solar photovoltaic (PV) system and the impact of the temperature on it. The analysis related to energy metrics, lifecycle costing, and environmental economics was performed considering the PV system's life as 30 years. The system economics is also compared at different conditions like theoretical, temperature-corrected, and real electricity generation data. The parameters like energy payback time (EPBT), energy return on energy invested (EROI), and lifecycle conversion efficiency are determined as 5.95 years, 5.04, and 0.078, respectively, based on actual generation. The unit electricity cost of the rooftop PV system was estimated as INR 5.37 at the 5% interest rate. The electricity cost varies with the interest rate variation and operation system life. The results show a reduction in overall economic performance on the increase in module temperature. The effect of temperature on the economics of the system is presented in terms of the per degree rise of module temperature. One degree increase of module temperature 8.5 days in EPBT of the PV system increases, and INR 0.021 increases in the unit cost of electricity considering a reference temperature 25 °C. A PV system has environmental benefits by reducing greenhouse gas emissions, which are also affected by the rise of module temperature. The system lost INR 355.93 in carbon credits at an increase of one-degree module temperature.

Performance enhancement of solar photovoltaic (PV) module using a novel flat plate (NFP) glass cover by reducing the effect of bird dropping (BD) settlement.

A massive bird dropping (BD) deposition on the common rectangular flat plate (RFP) of photovoltaic (PV) module is a matter of great concern in Western Rajasthan (WR) that diminish the overall energy production capacity of the system remarkably. In this research article, a prototype novel flat plate (NFP) design of a front glass cover of PV module is proposed to prevent the impact of BD settlement by the restriction of bird's sitting/movement on the front glass cover. In this regard, the performance analysis of PV module with common RFP and newly designed NFP glass covers has been assessed at the different inclination ß° (0-90). The BD accumulation onto the both glass covers was explored by the optical transmittance profiles at the different tilt angles, i.e., explained by bird movement on each flat glass surfaces. Consequently, a significant amount of output electric energy has been gained in NFP design rather than RFP corresponding to particular tilt regions TR I (0° ≤ ß ≤ 25°), TR II (25° ≤ ß ≤ 60°), and TR III (60° ≤ ß ≤ 90°). According to the results achieved, an excellent level of improvement in average power loss, ~ 97.85%, corresponding to optimal TR (III) has been detected by employing NFP glass collector.

A Study of Optimal Specifications for Light Shelves with Photovoltaic Modules to Improve Indoor Comfort and Save Building Energy.

Recent studies on light shelves found that building energy efficiency could be maximized by applying photovoltaic (PV) modules to light shelf reflectors. Although PV modules generate a substantial amount of heat and change the consumption of indoor heating and cooling energy, performance evaluations carried out thus far have not considered these factors. This study validated the effectiveness of PV module light shelves and determined optimal specifications while considering heating and cooling energy savings. A full-scale testbed was built to evaluate performance according to light shelf variables. The uniformity ratio was found to improve according to the light shelf angle value and decreased as the PV module installation area increased. It was determined that PV modules should be considered in the design of light shelves as their daylighting and concentration efficiency change according to their angles. PV modules installed on light shelves were also found to change the indoor cooling and heating environment; the degree of such change increased as the area of the PV module increased. Lastly, light shelf specifications for reducing building energy, including heating and cooling energy, were not found to apply to PV modules since PV modules on light shelf reflectors increase building energy consumption.

Data of a PV plant implemented in hot semi-arid climate.

This paper presents data collected from a 5.94 kWp grid connected photovoltaic (PV) plant implemented in hot semi-arid climate of Safi region, Morocco. The data include electrical power production and PV module temperature of three PV technologies: mono-crystalline (m-Si), poly-crystalline (p-Si), and amorphous (a-Si); they also include plane of array solar irradiance and ambient temperature. Solar irradiance was measured with calibrated reference cells, inverters provided the produced powers, and the temperatures were obtained by Pt100 probes. The data were measured each 5 min and were remotely accessible through internet. They were preprocessed to eliminate unrepresentative records and were used for the development of simple and accurate models for PV power forecasting [1]. These data are typical for hot semi-arid climate and may be reused for regional forecast of PV power as well as solar energy and PV module temperature predictions.

PV cells and modules - State of the art, limits and trends.

The key components of photovoltaic (PV) systems are PV modules representing basic devices, which are able to operate durably in outdoor conditions. PV modules can be manufactured using different materials by different fabrication technologies. The main criteria supporting or limiting a successful placement of particular technologies on the market is the cost of electricity produced by PV systems. The Levelized Cost of Energy (LCOE) method takes into account the investment cost, the operating costs, and the total energy produced during the system service life. The influence of price, efficiency and service life of PV modules on LCOE (together with the availability of materials) sets limits for applicable technologies. Over the past 15 years a categorisation of generations of PV cell and module technology groups has been frequently used. The main features of individual technology groups are discussed from the view of the above criteria. Currently, PV modules are required to have: efficiency higher than 14%, price below 0.4 USD/Wp and service life of more than 15 years. At present, the wafer-based crystalline silicon technologies have best met the criteria due to their high efficiency, low cost and long service time; and due to the abundance of materials, they are set to lead in future PV power generation.

Code and data from an ADALINE network trained with the RTRL and LMS algorithms for an MPPT controller in a photovoltaic system.

This paper presents a detailed description of the data obtained as a result of the computational simulations and experimental tests of an MPPT controller based on an ADALINE artificial neural network with FIR architecture, trained with the RTRL and LMS algorithms that were used as mechanisms of control in an off-grid photovoltaic system. In addition to the data obtained with the neural control method, the data for the MPPT controller based on the traditional Perturb and Observe (P&O) algorithm are presented. The simulations were performed in MATLAB/Simulink software without using the Neural Network Toolbox for controller training. The experimental tests were performed in an open space without shaded areas, exposing the neurocontroller to varying environmental conditions. Additionally, the scripts developed in MATLAB for the neural training algorithms used in the simulations are presented. These computational simulations were structured in five test cases to represent the behavior of each controller under varying environmental conditions. The codes developed in C are part of the implementation of the MPPT neurocontroller in the PIC18F2550, from which the experimental data were obtained. The data and codes presented in this research are available in the Mendeley Data repository, which allows evaluating the performance and optimizing the training algorithms with the purpose of improving the control methods applied to photovoltaic systems.

Experimental Application of Methods to Compute Solar Irradiance and Cell Temperature of Photovoltaic Modules.

solar irradiance and cell temperature are the most significant aspects when assessing the production of a photovoltaic system. To avoid the need of specific sensors for quantifying such parameters, recent literature presents methods to estimate them through electrical measurements, using the photovoltaic module itself as a sensor. This work presents an application of such methods to data recorded using a research platform at University of Corsica, in France. The methods and the platform are briefly presented and the results are shown and discussed in terms of normalized mean absolute errors (nMAE) and root mean square errors (nRMSE) for various irradiance and cell temperature levels. The nMAE (and nRMSE) for solar irradiance are respectively between 3.5% and 3.9% (4.2% and 4.7%). Such errors on computed irradiance are in the same order of magnitude as those found in the literature, with a simple implementation. For cell temperatures estimation, the nMAE and nRMSE were found to be in the range 3.4%-8.2% and 4.3%-10.7%. These results show that using such methods could provide an estimation for the values of irradiance and cell temperature, even if the modules are not new and are not regularly cleaned, but of course not partially shaded.

Comparative study of three different designs of a hybrid PV/T double-pass finned plate solar air heater.

In this paper, three different designs of a hybrid PV/T double-pass finned plate solar air heater (DPFPSAH) are investigated. The PV module is used to produce electricity needed to run the pump and blow the air into the solar collector. In the first design, the PV module is placed on the absorber plate of the air heater. In the second design, the PV module is placed beside the glass cover of the air heater; while, in the third one, the PV module is completely separated from the solar collector. The effects of mass flow rate of air, flow, and fan pumping powers are studied. The top losses of the third design are found to be higher than that of the first and the second designs by average values of 7.5% and 29%, respectively. The third design of the hybrid systems has the highest overall performance. The daily thermal efficiencies of the first, second, and third designs of the hybrid systems are obtained as 53%, 27%, and 64%, respectively, at mass flow rate of 0.02 kg/s.

Performance Degradation Analysis of c-Si PV Modules Mounted on a Concrete Slab under Hot-Humid Conditions Using Electroluminescence Scanning Technique for Potential Utilization in Future Solar Roadways.

The stability of the photovoltaic (PV) modules is critical when deployed in a non-ideal environment. Among the different factors, temperature and humidity are the two major factors affecting PV stability, making them significant causes of its degradation in terms of optoelectric and materials properties. Nowadays, with the increase in PV installation (here, we are only taking account of c-Si-based PV modules) to generate green electricity, effective space utilization is an important issue. Recently, people have been considering deploying PV modules on the road to utilize the space available on highways (roadways). This raises several new issues in the deployment of PV modules. However, issues related to temperature and humidity retain the same importance. Normally, these stability tests are performed in a damp-heat (DH) stress-testing chamber in an accelerated condition at 85 °C and 85% relative humidity (RH). In this work, c-Si PV modules were fixed over a concrete slab to prepare a PV interacted block, which can be used to build concrete-based roads. The performance of this PV on the concrete slab was tested in a DH stress-testing chamber in an accelerated condition at 85 °C and 85% RH for 4000 h. For the comparison, a PV module without concrete was also evaluated. The degradation of the PV modules was characterized using the electroluminescence scanning technique. After 2500 h of exposure to the DH conditions, the performance retention of the PV modules mounted on the concrete was 93.2%, which was nearly 5% higher than the module without the concrete slab.

Experimental study of dust deposition settled over tilted PV modules fixed in different directions in the southeast of Iran.

Degradation of photovoltaic system's power due to dust deposition is one of the important concerns of photovoltaic investors, especially the PV modules which are installed in the hot and dry parts of a country. This issue requires to be more understood and quantify its impact on the PV module performance in installation site. This study experimentally studied the dust deposition using several glasses which were fixed in the wooden frames at different tilt angles and directions in the southeast of Iran. The dust deposition on the glasses, solar energy reduction of the dusty glasses, and PV power reduction due to dust deposition were measured in all months of the year. The results showed that the average dust deposition on the glasses is 4.6 × 10-3 gr/m2day during the year. In case of no rain precipitation and no cleaning, this value reached 2.74 × 10-2gr/m2day. The percentage of solar energy reduction due to dust deposition was varied between 2 and 16% during the year. A correlation for prediction of the solar energy transmittance reduction based on the settled dust on the glass samples was developed in the studied region using 1-year data collection. The average solar energy reduction was obtained 7% during the year, and this value reached 44% in case of no rain precipitation and no glass cleaning. Results showed that in the most months of the year the wind direction and the direction of the glasses with the maximum dust deposition were coincided with each other. Furthermore, the experimental measurement showed that the calculated optimum monthly tilt angle in some months of the year is not the same with the measured tilt angle due to dust deposition. The difference between the calculated and measured tilt angles in these months was 15°.

Current Characteristics Estimation of Si PV Modules Based on Artificial Neural Network Modeling.

In the photovoltaic (PV) field, the outdoor evaluation of a PV system is quite complex, due to the variations of temperature and irradiance. In fact, the diagnosis of the PV modules is extremely required in order to maintain the optimum performance. In this paper, an artificial neural network (ANN) is proposed to build and train the model, and evaluate the PV module performance by mean bias error, mean square error and the regression analysis. We take temperature, irradiance and a specific voltage for input, and a specific current value for output, repeat several times in order to obtain an I-V curve. The main feature lies to the data-driven black-box method, with the ignorance of any analytical equations and hence the conventional five parameters (serial resistance, shunt resistance, non-ideal factor, reverse saturation current, and photon current). The ANN is able to predict the I-V curves of the Si PV module at arbitrary irradiance and temperature. Finally, the proposed algorithm has proved to be valid in terms of comparison with the testing dataset.

Impact of bird dropping deposition on solar photovoltaic module performance: a systematic study in Western Rajasthan.

One of the most critical challenges is bird dropping deposition (soiling) on a glass surface of the photovoltaic (PV) module in an open environment of Western Rajasthan. This paper has been now exclusively emphasized to focus on effects of the bird dropping phenomenon on the performance of PV systems. The presented study includes the impact of the seasonal bird dropping effect on the reduction in energy yield with various tilt angle configurations. Considering this, the highest level of reduction in power loss was observed at the end of winter (March) and minimum during rainfall (August) every year. The sitting/walking tendency of birds with the plate inclination directly affects the PV output, which is demonstrated by optical study of glass samples (bird dropping patterns). Consequently, the studies of optical transmittance conclude the effect of dropping with different tilt regions I (ß < 25°), II (25° ≤ ß ≤ 60°), and III (60° ≤ ß ≤ 90°), i.e., explained by bird movement onto the module surface. The result also showed that optimal inclination ß (40°) has a smaller soiling effect in tilt region II (25-60°) correspondingly.