Silicon Solar Modules Research Articles

Advanced room-temperature cured encapsulant film for crystalline silicon solar modules: enhancing efficiency with luminescent down-shifting, flame retardancy, and UV resistance.

Solar energy sources have garnered significant attention as a renewable energy option. Despite this, the practical power conversion efficiency (PCE) of widely used silicon-based solar cells remains low due to inefficient light utilization. In this study, carbon dots (APCDs) were prepared via a hydrothermal method using ammonium polyphosphate and m-phenylenediamine, then incorporated into a silicone-acrylic emulsion (CAS) to create a luminescent down-shifting (LDS) layer for solar cells. The CAS/APCDs films can be molded at room temperature and exhibit outstanding optical and adhesive properties. Application of CAS/APCDs films on solar cell surfaces effectively enhances photovoltaic performance, increasing current density (JSC) by 3.5% and overall PCE by 5.7%. Additionally, APCDs enhance flame retardancy in CAS films, increasing the limiting oxygen index from 29.3% to 32.0%, while reducing peak heat release and peak CO release by 20.2% and 38.9%, respectively. Moreover, APCDs absorb UV light and convert it into visible light, mitigating CAS film degradation. The aged CAS/1.0APCDs film exhibits superior morphology and mechanical properties compared to aged CAS film, maintaining 68.9% light transmission. Overall, this study introduces the development of room-temperature cured LDS layers with extended lifespan and flame retardant characteristics, offering promising applications in solar energy technology.

Electrochemical Separation of Copper and Tin for Silicon Solar Module Recycling

Silicon solar modules are the most common form of solar photovoltaic (PV) in the US. With a 30-year lifespan, how they are handled at their end-of-life will be crucial to return valuable materials to the industry and prevent hazardous waste from being released into the environment. Current solar recycling technologies often only aim for the recovery of silver (Ag), and less valuable metals like Cu (Cu) and Sn (Sn) are rarely considered. Moreover, hazardous metals like lead (Pb) are also often ignored, even though their buildup in the environment can lead to detrimental effects. Acid leaching is a common method for metals recycling, and the properties of Cu and Sn often lead to them present in the same solution when part of a broader leaching sequence. Thus, this research aims to further understand the separation of Cu and Sn in a hydrochloric acid (HCl) stream in a way that is both circular and maximizes recovery. With the reactions involved, the acid should be consumed during leaching and regenerated during electrowinning, resulting in a circular process that requires minimal chemical input. Electrochemical analysis was performed to determine optimal recovery conditions for both Cu and Sn. Cyclic voltammetry was utilized to determine thermodynamic reduction potentials for both metals. Tafel analysis was used to determine some electrochemical kinetic parameters. Electrochemical impedance spectroscopy (EIS) also allowed the determination of relevant kinetics parameters. Chronoamperometry was used to recovery the metals with a constant applied voltage with respect to a reference electrode (Ag/AgCl). The resulting cathodes were then analyzed with energy dispersive x-ray spectroscopy (EDS) coupled with a scanning electron microscope (SEM). Recovery rates and current efficiencies were determined by concentrations of metal cations in solution through Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Cyclic voltammetry determined the reduction potential peak for Cu and Sn to be -0.44 V and -0.92 V vs. Ag/AgCl respectively. Applied potentials with respect to the Ag/AgCl reference of -0.4 V, -0.45 V, -0.5 V, -0.55 V and -0.6 V for 8 hours were explored for Cu recovery, and their recovery rates were 0%, 8.6%, 82.8%, 84.2%, and 88.5% respectively. The coulombic efficiencies associated with these tests were 0%, 4.5%, 29.6%, 28.2% and 30.0%. Throughout all these tests, no Sn was recovered on the cathode. The Sn remained in solution as determined through ICP-OES. From a solution after Cu electrowinning, -1.0 V was applied for Sn recovery. The recovery rate for this was 100% with a coulombic efficiency of 14.5%. The cathodic deposits revealed >99% pure Cu and Sn during their respective recovery steps. Therefore, it was concluded that Cu and Sn could be electrochemically separated through this method. Through Tafel analysis and EIS, the kinetics parameters for Cu and Sn electrowinning were determined. For Cu, the symmetry factor (α) was determined to be 0.35 and the exchange current density (Io) was determined to be 4.68 mA/cm2. For Sn, α was 0.13 and Io was 26.6 mA/cm2. Solar recycling will be a must in the future circular economy, and developing low cost, chemically circular methods to perform recycling will help to incentivize scaling these processes to a point where they are useful. This research provides a method of separating Cu and Sn as pure components for recycling solar panels.

Voltage root mean square error calculation for solar cell parameter estimation: A novel g-function approach

The existing research on estimating solar cell parameters mainly focuses on minimizing the Root-Mean-Square Error (RMSE) between the estimated and measured current values of solar cells (referred to as the RMSEI). This involves using an analytical expression for current - I as a function of voltage - U (I = f1(U)) expressed through the Lambert W function. This paper introduces a new analytical solution for calculating the RMSE between measured and estimated solar cell voltages (referred to as the RMSEU). The formula is derived using the g-function or LogWright function, which provides a numerically applicable method for representing the analytical relation between solar cell voltage and current (U = f2(I)). Moreover, the paper presents the original formulas for calculating Mean Absolute Error (MAE) and Mean Absolute Percentage Error (MAPE) for solar cell voltages expressed through the g-function. The paper also compares various published approaches and examines two well-known solar cells/modules, namely the RTC France solar cell and the SOLAREX MSX–60 PV solar module, in terms of the RMSEU and single-diode solar cell models. Additionally, a novel metaheuristic algorithm, known as the Chaotic Walrus Optimization Algorithm (Chaotic-WaOA), is proposed for solar cell parameter estimation. This algorithm is applied to both mentioned solar cells to determine their parameters in terms of minimal RMSEU. In order to verify the proposed research, experimental observations were conducted on a 60Wp monocrystalline solar module installed at the Faculty of Sciences and Mathematics in Niš, Serbia. This was done using a specialized PV-KLA apparatus under different outdoor conditions. The research was also verified with a Cadmium telluride solar module (CdTe75638) and a multi-crystalline silicon solar module (mSi0188). The investigation results demonstrate the accuracy, applicability, and numerical feasibility of the proposed RMSE expression and algorithm. Additionally, the study confirms the applicability of the g-function in invertible solar cell modeling.

Sustainable Strategies for Crystalline Solar Cell Recycling: A Review on Recycling Techniques, Companies, and Environmental Impact Analysis

Solar PV is gaining increasing importance in the worldwide energy industry. Consequently, the global expansion of crystalline photovoltaic power plants has resulted in a rise in PV waste generation. However, disposing of PV waste is challenging and can pose harmful chemical effects on the environment. Therefore, developing technologies for recycling crystalline silicon solar modules is imperative to improve process efficiency, economics, recovery, and recycling rates. This review offers a comprehensive analysis of PV waste management, specifically focusing on crystalline solar cell recycling. The classification of PV recycling companies based on various components, including solar panels, PV glass, aluminum frames, silicon solar cells, junction boxes, plastic, back sheets, and cables, is explored. Additionally, the survey includes an in-depth literature review concentrating on chemical treatment for crystalline solar cell recycling. Furthermore, this study provides constructive suggestions for PV power plants on how to promote solar cell recycling at the end of their life cycles, thereby reducing their environmental impact. Moreover, the techno-economic and environmental dimensions of solar cell recycling techniques are investigated in detail. Overall, this review offers valuable insights into the challenges and opportunities associated with crystalline solar cell recycling, emphasizing the importance of economically feasible and environmentally sustainable PV waste management solutions in the constantly evolving solar energy market.

Recovery of metallic lead from End-Of-Life silicon solar modules using salt bridge electrowinning

Toxic lead (Pb) in end-of-life silicon solar modules must be recovered to keep it out of the environment. Present literature on Pb recovery from solar waste is sparse and uses chemicals like nitric or hydrochloric acid. Previously, the authors reported Pb recovery from silicon modules by leaching and electrowinning in acetic acid. However, the Pb recovered from acetic solution contained a small amount of metallic Pb with the rest being lead oxides/acetates. These Pb compounds require further processing to obtain metallic Pb for reuse in solar panel solder, leading to additional cost and chemical waste. This paper reports recovery of metallic Pb using an electrochemical system with two half cells connected through a salt bridge. The salt bridge enables optimized recovery rates of Pb as high as 99.99 % for synthetic leachates. The first experiment to recover Pb from real silicon module waste shows 80 % recovery without optimization. The new method offers a low-cost, closed-loop, direct pathway to metallic Pb recovery from end-of-life silicon solar modules for reuse in new modules.

The impact of some environmental variables on the performance of solar PV module

The country of Iraq tops the list of countries in solar activity and therefore has the most important renewable energy sources, which we desperately need to fill the acute shortage of electrical energy. The availability of this source coincides with a significant rise in temperature in most of its regions and a wide range of days of the year. Where temperatures play a key role in wind activity and the provocation of dust storms, which urgently requires a field study to find out the impact of these factors on the performance of photovoltaic solar modules. Therefore, this study aimed to evaluate the performance of the solar module under the influence of dust accumulation, temperature and wind speed. A group symmetric of monocrystalline silicon solar modules have been experimented to see how these factors affect the performance of the modules. The results showed that there is a clear impact by the heat factor and dust accumulation on the performance of solar modules, but the wind factor is the least influential and what can be concluded is that Iraq, especially the city of Baghdad, is an ideal place to invest solar energy in the production of electrical energy.

New Chemistries for Silver and Lead Recovery from End-of-Life Silicon Solar Modules

Two metals contained in silicon solar modules belong to the must-recover category: silver and lead. Silver is the main financial incentive for recyclers generating ~$5/module, while lead is toxic creating a potential environmental hazard when landfilled. The literature on silver recovery often employs nitric acid for leaching followed by precipitation, re-dissolution, and electrowinning to recover metallic silver, while lead recovery has been rarely attempted for silicon module recycling. In this talk we will report silver recovery with hydrofluoric acid. It involves two steps, leaching and electrowinning to recover over 95% of the silver as a pure metal. A two-step process of leaching and electrowinning for lead recovery with acetic acid will also be reported. A recovery rate of over 99% has been confirmed, with the lead content in the post-electrowinning leachate below 10 ppm and the recovered lead being a pure metal. However, the recovered lead tends to react with ambient and acetic acid to form surface oxide and/or acetate due to its dendritic morphology. A dense lead deposit is preferred.

Power Generation Performance of CdTe Thin Film Solar Modules in Lhasa

With the increasing energy consumption of buildings, reducing the energy consumption of buildings has become a key link to achieving the goal of carbon neutrality. Building integrated photovoltaic (BIPV) is an important research direction. Based on the CdTe thin film solar modules power generation system on the south-facing wall of a building in Lhasa, the article collected the annual power generation data for 2022. The characteristics and variation patterns of the total monthly power generation and typical monthly daily power generation are analyzed. Furthermore, the correlation between power generation performance and the main influencing factors was analyzed. The differences in power generation characteristics between CdTe thin films solar modules and single crystal silicon solar modules were compared and analyzed. The results show that the annual power generation of the CdTe thin film solar modules power generation system exhibits a “U” shaped distribution, and the power generation in winter is greatly affected by weather conditions. The peak power of 1kWp CdTe thin film solar modules is lower than that of single crystal silicon solar modules. The generation duration is longer than single crystal silicon solar modules. The total power generation is greater than single crystal silicon solar modules.

Addressing sodium ion-related degradation in SHJ cells by the application of nano-scale barrier layers

Silicon heterojunction (SHJ) solar cells are renowned for their high efficiency. However, SHJ solar cells are susceptible to various contaminants, leading to significant performance degradation when exposed to damp-heat conditions (e.g., 85 °C and 85% relative humidity). Sodium (Na) has been identified as one of the main contributors to degradation in silicon solar modules subjected to damp-heat conditions. This work investigates the role of an ultra-thin AlOx capping layer (∼10 nm) in preventing the failure in SHJ cells caused by Na-related contaminants. NaCl is applied directly to the solar cell, and the unencapsulated cell undergoes a damp heat test at 85 °C and 85% relative humidity (DH85). It is found that without the AlOx barrier layer, the SHJ cells experience a relative reduction in power of ∼30%rel after only 20 h at DH85. Both the front and rear sides of the cell degrade when exposed to NaCl. This is primarily due to a deterioration of the Ag contact resulting in increased series resistance (Rs), and decrease in fill factor (FF), and an increase in recombination, leading to a significant drop in open-circuit voltage (Voc), particularly when NaCl is applied on the rear side. However, when an AlOx barrier layer is applied to the SHJ cells, the performance losses caused by NaCl are significantly reduced to only ∼3.3%rel. The loss in Voc on the rear side is completely suppressed, and there is only a slight increase in Rs of ∼50%rel compared to ∼300%rel increase in Rs for cells without the AlOx barrier layer. These findings indicate that the ultra-thin AlOx barrier layer provides effective protection for SHJ cells against Na ions, mitigating both Rs and recombination losses. This AlOx barrier layer depositing method is compatible with existing industrial mass-production ALD tools and thus presents a viable solution at the cell level for SHJ cells.

Performance degradation and reliability evaluation of crystalline silicon photovoltaic modules without and with considering measurement reproducibility: A case study in desert area

In this paper, performance degradation and reliability evaluation of crystalline silicon photovoltaic modules deployed in desert climate was investigated based on the more than 7-year tracking test. It is found that peak power standard deviation first increased with time, reaching the peak when modules operated for 3 years, and then continuously decreased. Then, relationship among power warranty, power degradation rate and tolerance on maximum power is revealed for the first time. If 1% of module failures during warranty period is allowable, the 30-year warranty can be realized when degradation rate is 0.4–0.6 %/year with tolerance 0 ∼ +5% and 0 ∼ +3%, or degradation rate is 0.5 %/year with tolerance ±5% and ±3%, or degradation rate is 0.4 %/year with tolerance ±10%, ±5% and ±3%. Finally, reproducibility of power measurement is introduced for more accurately evaluating module performance degradation and reliability. Meanwhile, determination procedure of reproducibility for module electrical performance is systematically set forth. It is found that power warranty period can be prolonged if reproducibility is considered. The results obtained in this paper can provide new insights into performance degradation, reliability assessment and power warranty for fielded crystalline silicon solar modules.

Development of lightweight and flexible crystalline silicon solar cell modules with PET film cover for high reliability in high temperature and humidity conditions

Lightweight and flexible solar cell modules have great potential to be installed in locations with loading limitations and to expand the photovoltaics market. We used polyethylene terephthalate films instead of thick glass cover as front cover materials to fabricated lightweight solar cell modules with crystalline silicon solar cells. Because of the absence of a glass cover, the fabricated modules have flexible properties. The fabricated modules were subjected to accelerated degradation tests to evaluate their reliability. The test results showed that these lightweight and flexible modules exhibit high reliability under both high temperature and high humidity conditions.

Growth and analysis of polycrystalline silicon ingots using recycled silicon from waste solar module

The proliferated growth of the Photovoltaic industry (PV) will eventually lead to unprecedented volumes of silicon-based solar waste. Failing to manage high volumes of waste, can lead to a huge amount of silicon metal loss and is also highly conducive to posing an environmental hazard. Therefore, efficient recovery and re-utilization after proper purification of the PV-waste-based silicon are highly obligatory for the sustainable development of the PV industry. Herein, we report the growth of small-size silicon ingots (φ = 0.5 inch, 1.0 inch) produced from recovered silicon from the waste crystalline silicon (c-Si) solar module through the Spark Plasma Sintering (SPS) technique. The silicon feedstock was prepared, after the extraction of silicon cells from the used panel and chemically etching contacts, ARC (anti-reflection coating), from the cells in order to recover the silicon wafer. The silicon wafer pieces were pulverized to produce very fine powder and subsequently processed at a different set of temperature-pressure for the study of density variation. The highest density (2.33 gm/cm3) equal to the theoretical density of silicon was obtained for sample grown at temperature 1200 °C and pressure 60 MPa. The purity of the obtained ingots was found to be greater than 3 N and therefore, can find use in different industries.

Comparative analysis of outdoor energy harvest of organic and silicon solar modules for applications in BIPV systems

Organic photovoltaics (OPV) have the potential to fill niches that traditional silicon photovoltaics (Si-PV) have left open so far. Building-integrated photovoltaics (BIPV) is one key area where OPV modules can play a vital role due to their functional attributes of semitransparency, flexibility, and lightweight. However, the architectural constraints and physical layout of buildings often do not allow the installation of photovoltaic (PV) modules at their optimal angles. Herein, we report the outdoor energy harvest of commercial OPV, and monocrystalline silicon (m-Si) modules mounted at inclinations of 45° and 90°, using the ISOS-O2 protocol as a test standard. The semitransparent OPV modules incorporating a P3HT:PCBM bulk heterojunction absorbing layer were found to offer daily specific energy yields (YF) that are 10–15% higher than those of the m-Si modules at 45° inclination. For vertical (90°) mounting, the YF of the OPV modules is even 24–30% higher than that of their inorganic counterparts, thus making them ideally suited for façade integrated BIPV. Laboratory investigations reveal that the superior performance of OPV modules in the vertical position is mainly due to a strongly enhanced fill factor (FF) at reduced in-plane irradiance. At a 45° inclination, the positive temperature coefficient of the OPV modules also plays an important role during high-irradiance hours.

Short Wavelength Photons Destroying Si–H Bonds and Its Influence on High‐Efficiency Silicon Solar Cells and Modules

Photons of varying wavelengths exert substantial effects on silicon heterojunction (SHJ) solar cells. Collaborative research previously establishes that light soaking with long‐wavelength photons can activate boron doping in hydrogenated amorphous silicon (a‐Si:H), thereby augmenting cell efficiency (Eff). Herein, this investigation is extended, exploring the effects of short‐wavelength photons on a‐Si:H layers, SHJ solar cells, and modules. The ultraviolet A (UVA) light with the wavelengths peak of 365 nm can disrupt Si–H bonds, resulting in a notable reduction in hydrogen content within both intrinsic and doped a‐Si:H films, and the deterioration of deteriorated interface passivation. Following exposure to 60 kWh m−2 of UVA light, both Eff and module power output decrease significantly, primarily attributable to the degradation of open‐circuit voltage and fill factor. As a feasible solution, the application of a light‐soaking process or the implementation of UV band cutoff module encapsulants can effectively mitigate the loss induced by UV irradiation, thereby ensuring the long‐term operation of SHJ solar cells and modules. Herein, a deeper understanding of UV‐induced performance changes in a‐Si:H film and its degradation mechanism for SHJ solar cells are contributed to in this research and also a viable strategy is provided to counter UV‐induced degradation.

See‐Through Flexible Photovoltaic Modules of Ultrathin Silicon Solar Microcells Enhanced by Synergistic Luminescent and Reflective Near‐Infrared Backplanes

AbstractUltrathin single‐crystalline silicon solar microcells assembled into see‐through and flexible modules have exhibited broadly applicable cost‐effective photovoltaics with reliable durability and efficiency. However, their module output power has suffered from inherent limitations caused by the inferior photon absorption property and the inactive see‐through windows. Herein a strategy is presented to enhance the performance of see‐through flexible ultrathin silicon microcell modules by employing visibly transparent but near‐infrared‐manipulatable optical backplanes, such as a luminescent waveguide gathering near‐infrared photons and a backside reflector mitigating near‐infrared photon escape. Simultaneous integration of these near‐infrared backplanes provides more photovoltaic gains to silicon solar modules than the sum of each backplane capability, and this synergy is due to the promoted properties of the photoluminescence process and waveguiding. The experimental module with ≈3‐µm thick silicon solar microcells can achieve up to ≈40%‐boosted output power generation when assisted by these backplanes. Detailed studies of optical and photovoltaic characterizations for near‐infrared backplanes and their integration modules elucidate the effectiveness of designed backplanes for see‐through flexible silicon photovoltaics.

Overall Design and Power Generation Calculation of Photovoltaic System in Shanyin meteorological station

Based on the data of Shanyin meteorological station and Solargis database, this paper evaluates the local solar energy resources, and carries out the overall scheme design and power generation estimation of the feasibility study stage of the 50MW photovoltaic power generation project in Shanyin county. After analysis, it is proposed to select crystalline silicon solar modules for the project. The specification of polycrystalline silicon solar modules is 305wp, and the specification of monocrystalline silicon solar modules is 315wp. It is recommended to adopt fixed installation for the photovoltaic module array. In addition, the component support of the project is fixed with an installation angle of 35°. 500mx inverter is selected for the project because of its high cost performance ratio. Based on the above work, the total power generation in 25 years is calculated.

An evaluation of the impact framework for product stewardship on end-of-life solar photovoltaic modules: An environmental lifecycle assessment

The growth of solar photovoltaic (PV) waste in the coming years requires implementation of effective management options. Australia, with one of the highest rates of rooftop solar PV, is still developing policy options to manage these panels when they reach their end-of-life. This study evaluates the environmental impacts of three options for mono and multi crystalline silicon (c-Si) solar panel waste modules. The impact of transport distance from transfer stations to the recycling centre is also assessed. The life cycle assessment revealed that, -1 E+06 kgCO2eq and -2 E+06 kgCO2eq are associated with the mandatory product stewardship scenarios under global warming potential for mono and multi c-Si solar modules, respectively. However, the non-existence of a product stewardship will produce a global warming impact of 1 E+05 kgCO2eq for both modules. The global warming effects revealed that, collecting and recycling most of the multi c-Si panels were not effective (−365.00 kg CO2-eq, −698.40 kg CO2-eq, −1032.00 kg CO2-eq) compared to keeping them away from the landfills and fully recycling (-2 E+06 kg CO2-eq) them. It was also highlighted that, the highest environmental impact regarding the transport distances was the scenario of one recycling centre serving over 107 transfer stations with a global warming potential of 1 E+06 kgCO2eq. This research model serves as the first conceptual and methodological framework for life cycle assessment (LCA) in policy and transport related analysis. Since transport is incredibly significant in PV recycling processes, it is recommended that, to further reduce these impacts, other forms of low-impact modes of transportation should be explored.

Optimization of a Molybdenum Oxide Bilayer Facilitating Hole Transfer in the p/i Interface for Transparent Thin-Film Silicon Solar Cells and Modules Using Laser Scribing

Optimization of a Molybdenum Oxide Bilayer Facilitating Hole Transfer in the p/i Interface for Transparent Thin-Film Silicon Solar Cells and Modules Using Laser Scribing

A simulated study on the performance evaluation of amorphous silicon solar PV module for temperature, irradiance and tilt angle dependence

The performance of an amorphous silicon solar PV module is tested at various irradiance levels, operation temperatures and tilt angles using a solar simulator. Electrical efficiency, V-I characteristics and power conditioning curves are generated at various solar irradiance levels of 400, 700 and 1000 W/m2, cell operation temperature range of 40 to 100°C and various panel tilt angles of 0°, 15°, 30°, 45° and 60° with horizontal. Solar equations are used to compute the maximum swing angle of the sun away from the normal position of the panel at noon (l) during different months and latitudes. Analogy between the simulated study and l (for real operation conditions) for polar mounted inclinations of PV panels, winter & summer maximization inclinations of the PV panels and south facing vertical walls/windows for different months of the year and at various latitudes is established and the effect of l on the percent reduction in maximum power produced (Pmp) by the PV solar panel is studied. The tilt angle dependence shows that the panel produces highest Pmp at l = 0° (tilt angle of the panel when the light source is normal to the panel surface). It is also observed that Pmp decreases by about 9%, 14 % and 19% when l is 15°, 30° and 45° respectively as compared to the normal position of the panel. Newton-Raphson’s technique is used to theoretically compute Imp, Vmp & Pmp and compared with the experimental values generated using the solar simulator within less than 5% deviation.

A simulated study on the performance evaluation of amorphous silicon solar PV module for temperature, irradiance and tilt angle dependence

A simulated study on the performance evaluation of amorphous silicon solar PV module for temperature, irradiance and tilt angle dependence