Rear Cell Research Articles

A REVIEW OF Solar Panel Efficiency: The Influence of Installation Angles and Design

This contrasts performance under different conditions of air, how these solar cell technologies can optimize solar energy conversion efficiency in specific locations. The intention of this information on the best applications is to consider cost, efficiency, and environmental considerations. These findings of the present study will contribute to ongoing efforts at making solar energy use better and more efficient, thereby accelerating the transition towards a greener energy future. All these technologies, including monocrystalline, polycrystalline, thin-film, and Passivated Emitter and Rear Cell (PERC) solar cells, have been developed to convert the energy received from the sun efficiently. As far as conversion efficiency is concerned, every technology has its plus points and negative points, especially in different climatic situations. These monocrystalline solar cells are known for their great endurance and efficiency in functioning remarkably well, even in hot and sunny conditions. Even though not as efficient as the monocrystalline counterparts, polycrystalline solar cells are still affordable and work satisfactorily in temperate climates. With their flexibility and low weight, thin-film solar cells work well with low light conditions and may be applied in many applications, such as building-integrated photovoltaics. They have greater capacity for absorbing light and lesser electron. Keywords: monocrystalline, polycrystalline, thin-film, and PERC (Passivated Emitter and Rear Cell).

Pathways in Biomimicry to Enhance Solar Technology Capabilities

Efficiency, longevity, and cost-effectiveness in current solar modules are compromised in pursuit of best balancing one another. This report explores the potential of enhancing solar cell practicability through biomimicry. Like solar cells, biological organisms absorb heat during photosynthesis, positioning nature as an inherent source of inspiration to tackle current technological challenges. Significant improvements have been achieved by mimicking structures such as the leaf epidermis for multidirectional light capture, cell membranes for protective encapsulation, and butterfly wings for enhanced light absorption and reflection. For instance, incorporating a BT layer for thermoregulation mimics plant transpiration, enhancing cooling efficiency. Additionally, hierarchical structures inspired by leaf geometry increases angular robustness in both dye-sensitized solar cells and passive emitter and rear cells, and lipid biomolecule interactions shelter halide perovskites from environmental degradation. The nanostructures of butterfly wings also show promise in supporting thin film PVs to overcome conversion inefficiency. Lastly, the reflective properties of butterfly wings have led to advancements in solar concentrators, improving power-to-weight ratios. These examples highlight the untapped potential of biomimicry in furthering the viability and deployment of solar technologies.

Ring Defects Associated with Boron–Oxygen‐Related Degradation in p‐Type Silicon Heterojunction Solar Cells

Silicon heterojunction (SHJ) cell architectures, which have dominated silicon single‐junction efficiency records for the past 10 years, are processed at relatively low temperatures, on the order of ≈250 °C. Recombination‐active oxygen complexes in crystalline silicon, formed from interstitial oxygen (Oi), typically require temperatures higher than this to form. Therefore, it is typically assumed that SHJ cells are immune to such defects. This contrasts with the high‐temperature passivated emitter and rear cell (PERC) and tunneling oxide passivating contact (TOPCon) architectures, which can suffer from oxygen precipitates that are recombination active and difficult to predict. Herein, ring‐like defects are observed in boron‐doped p‐type SHJ solar cells, which leads to a degradation of open‐circuit voltage. It is shown that the spatial variation of this recombination activity is related to the boron–oxygen defect, the variation of which is likely due to the radial Oi distribution. Although boron‐doped p‐type wafers are no longer the industry standard, the defect engineering of wafers for SHJ production, using high‐temperature processing, is gaining significant interest. Such wafers can have an increased susceptibility to ring‐like defects. Therefore, spatially inhomogeneous defects causing recombination may become increasingly relevant for SHJ cells.

Defect passivation engineering for achieving 4.29% light utilization efficiency MA-free wide-bandgap semi-transparent perovskite solar cells

Wide-bandgap perovskite materials are a great candidate for semitransparent perovskite solar cells (ST-PSCs) due to their tunable bandgap, outstanding transparency, and excellent photovoltaic performance. Though Br-rich perovskite can widen the bandgap, Br influences the crystallization dynamic speed leaving small perovskite grain sizes and high defects. Surface passivation engineering has been one of the best choices to suppress defects caused by the rapid crystallization of Br-rich perovskites. Herein, we applied MA-free perovskite as a light absorber because of the erratic thermal aging of MA-containing perovskites and selected phenethylammonium iodide (PEAI) and 4-trifluoro phenylethylammonium iodide (CF3PEAI) as passivation materials for improving the performance of opaque PSCs and ST-PSCs. Consequently, CF3PEA possesses a larger dipole moment. It has been demonstrated to exhibit a stronger binding energy with the substrate than PEA by density functional theory (DFT) calculations. This enhanced molecular interaction underpins the performance improvements in our solar cells, which manifests as an inverted planar structure opaque PSCs with 1.78 eV bandgap achieve a power conversion efficiency (PCE) of 17.09 % with excellent stability. A PCE of 17.17 % with 25 % average visible-light transmittance (AVT) and 4.29 % light utilization efficiency (LUE) of ST-PSCs is achieved by further optimizing the fabrication process of the buffer layer for protecting the perovskites from the damage of ITO sputter. Meanwhile, a four-terminal tandem solar cell with ST-PSC and silicon-based passivated emitter rear cell (PERC) obtains a PCE of 26.28 %. This work provides a feasible way to fabricate high-performance ST-PSCs with limited materials and preparation conditions.

Aluminum-Doped Indium Oxide Electron Transport Layer Grown by Atomic Layer Deposition: Highly Efficient and Damage-Resistant Interconnection Solution for All-Perovskite Tandem Solar Cells with 25.46% Efficiency.

In fabricating high-efficiency all-perovskite tandem solar cells (APTSCs) with a p-i-n configuration, the electron transport layer (ETL) plays a critical role in facilitating the transport of photogenerated electrons from the front cell to the recombination layer and protecting the front cell from damage during rear cell fabrication. This study introduces aluminum-doped In2O3 (AIO) films grown by atomic layer deposition (ALD) as a promising ETL for high-efficiency APTSCs. ALD-grown AIO films with an optimized Al concentration exhibit superior charge transport characteristics, excellent transparency, and damage-resistant barrier properties against solution infiltration compared with conventional SnO2 ETLs and undoped ALD In2O3. Using an ALD SnO2/3 at.% AIO bilayer as the electron transport layer, an efficiency of 18.33% is achieved from single-junction wide bandgap perovskite solar cells. Furthermore, the use of ALD SnO2/3 at.% AIO ETL enables the reliable fabrication of APTSCs with negligible solution damage to the front cell and minimized power loss. Consequently, APTSC employing the ALD AIO-based ETL exhibit an excellent photoconversion efficiency of 25.46%, outperforming APTSCs with the ALD SnO2 ETL.

Isomeric diammonium passivation for perovskite-organic tandem solar cells.

In recent years, perovskite has been widely adopted in series-connected monolithic tandem solar cells (TSCs) to overcome the Shockley-Queisser limit of single-junction solar cells. Perovskite/organic TSCs, comprising a wide-bandgap (WBG) perovskite solar cell (pero-SC) as the front cell and a narrow-bandgap organic solar cell (OSC) as the rear cell, have recently drawn attention owing to the good stability and potential high power conversion efficiency (PCE)1,2,3,4. However, WBG pero-SCs usually exhibit higher voltage losses than regular pero-SCs, which limits the performance of TSCs5,6. One of the major obstacles comes from interfacial recombination at the perovskite/C60 interface, and it is important to develop effective surface passivation strategies to pursue higher PCE of perovskite/organic TSCs7. Here we exploit a new surface passivator cyclohexane 1,4-diammonium diiodide (CyDAI2), which naturally contains two isomeric structures with ammonium groups on the same or opposite sides of the hexane ring (denoted as cis-CyDAI2 and trans-CyDAI2, respectively), and the two isomers demonstrate completely different surface interaction behaviors. The cis-CyDAI2 passivation treatment reduces the Quasi-Fermi level splitting (QFLS)-open circuit voltage (Voc) mismatch of the WBG pero-SCs with a bandgap of 1.88 eV and enhanced its Voc to 1.36 V. Combining the cis-CyDAI2 treated perovskite and the organic active layer with a narrow-bandgap of 1.24 eV, the constructed monolithic perovskite/organic TSC demonstrates a PCE of 26.4% (certified as 25.7%).

Novel optimized models to enhance performance forecasting of grid-connected PERC PV string operating under semi-arid climate conditions

This study focuses on modeling and forecasting the performance of a grid-connected photovoltaic (PV) string, aiming to enhance the accuracy of output power prediction, which is crucial for the effective management and stability of the electrical grid. While previous research has extensively examined PV modules, there is a notable lack of studies specifically targeting PV string behaviors, especially in harsh climates prevailing in semi-arid regions. This study addresses this gap by investigating the modeling and performance prediction of a Passivated Emitter Rear Cell (PERC) PV string under semi-arid climate conditions using analytical and predictive approaches based on both implicit and explicit models as Single Diode Model (SDM), Das Model (DM), Boutana et al. Model (BM) and Power Law Model (PLM). New mathematical models of DM and BM shape parameters versus temperature and irradiance along with novel analytical formulas giving DM shape parameters as a function of PV metrics have been introduced. The proposed approaches are validated using real measurements of a PERC PV string incorporating 12 JKM405M-72H PV modules operating at Green Energy Park (GEP) research facility in Morocco. The reliability of these approaches is assessed by comparing I-V curves, P-V curves and peak power generated and predicted by SDM, DM, BM and PLM to actual measurements. The comparison reveals that generated and predicted outcomes align well with measured data, with an average value of Normalized Root Mean Square Error (NRMSE) not exceeding 4.16 % for all models throughout the day. The findings indicate that the proposed approaches effectively predict the performance of the PERC PV string, accounting for climatic influences and providing insights into optimizing PV system performance, thereby contributing to improved grid stability in semi-arid regions.

Development and Characterization of N2O-Plasma Oxide Layers for High-Temperature p-Type Passivating Contacts in Silicon Solar Cells.

Full-area passivating contacts based on SiOx/poly-Si stacks are key for the new generation of industrial silicon solar cells substituting the passivated emitter and rear cell (PERC) technology. Demonstrating a potential efficiency increase of 1 to 2% compared to PERC, the utilization of n-type wafers with an n-type contact at the back and a p-type diffused boron emitter has become the industry standard in 2024. In this work, variations of this technology are explored, considering p-type passivating contacts on p-type Si wafers formed via a rapid thermal processing (RTP) step. These contacts could be useful in conjunction with n-type contacts for realizing solar cells with passivating contacts on both sides. Here, a particular focus is set on investigating the influence of the applied thermal treatment on the interfacial silicon oxide (SiOx) layer. Thin SiOx layers formed via ultraviolet (UV)-O3 exposure are compared with layers obtained through a plasma treatment with nitrous oxide (N2O). This process is performed in the same plasma enhanced chemical vapor deposition (PECVD) chamber used to grow the Si-based passivating layer, resulting in a streamlined process flow. For both oxide types, the influence of the RTP thermal budget on passivation quality and contact resistivity is investigated. Whereas the UV-O3 oxide shows a pronounced degradation when using high thermal budget annealing (T > 860 °C), the N2O-plasma oxide exhibits instead an excellent passivation quality under these conditions. Simultaneously, the contact resistivity achieved with the N2O-plasma oxide layer is comparable to that yielded by UV-O3-grown oxides. To unravel the mechanisms behind the improved performance obtained with the N2O-plasma oxide at high thermal budget, characterization by high-resolution (scanning) transmission electron microscopy (HR-(S)TEM), X-ray reflectometry (XRR) and X-ray photoelectron spectroscopy (XPS) is conducted on layer stacks featuring both N2O and UV-O3 oxides after RTP. A breakup of the UV-O3 oxide at high thermal budget is observed, whereas the N2O oxide is found to maintain its structural integrity along the interface. Furthermore, chemical analysis reveals that the N2O oxide is richer in oxygen and contains a higher amount of nitrogen compared to the UV-O3 oxide. These distinguishing characteristics can be directly linked to the enhanced stability exhibited by the N2O oxide under higher annealing temperatures and extended dwell times.

Cost‐efficiency potential of solar energy on a global scale: Case studies for Si solar modules with PERC and heterojunction structures

AbstractLevelized cost of electricity (LCOE) is a crucial metric for assessing the socio‐economic cost‐efficiency potential of various energy sources including solar photovoltaics. Nevertheless, accurate LCOE estimations for commercialized high‐efficiency Si solar modules with passivated emitter and rear cell (PERC) and silicon heterojunction (SHJ) structures have been lacking. In this study, we present the first global LCOE estimates for a PERC module (20% cell efficiency) and a SHJ module (23% cell efficiency), which have been derived by (i) performing rigorous energy‐yield calculations with full‐spectral and temperature‐dependent simulations that incorporate all essential meteorological effects and (ii) considering country‐specific capital costs and discount rates. Moreover, to determine the universal global LCOE, the LCOEs for three distinct installation capacities (100 MW for a utility, 500 kW for a commercial, and 5 kW for a residential system) have been unified by selecting an appropriate system size at each location based on a population density. We find that the LCOEs of both PERC and SHJ systems are below 3 cents/kWh in 2020 US dollar in many areas of China, Saudi Arabia, the United States, Australia, Chile, and Botswana, where the conditions of a high energy yield, low population density, low capital cost, and low country‐risk premium are satisfied simultaneously. In contrast, many European countries exhibit a moderate LCOE of 3~5 cents/kWh. Notably, Japan and Russia exhibit quite high LCOEs (6~10 cents/kWh) primarily due to significantly higher installation costs and moderate energy yields. Importantly, the global LCOEs of the PERC and SHJ modules are quite similar, with the SHJ module showing a slightly better cost performance in the regions near the equator due to its low temperature coefficient. Conversely, the PERC module demonstrates a cost advantage in the Northern Hemisphere due to a lower module cost.

Crystal Symmetry-Inspired Algorithm for Optimal Design of Contemporary Mono Passivated Emitter and Rear Cell Solar Photovoltaic Modules

A metaheuristic algorithm named the Crystal Structure Algorithm (CrSA), which is inspired by the symmetric arrangement of atoms, molecules, or ions in crystalline minerals, has been used for the accurate modeling of Mono Passivated Emitter and Rear Cell (PERC) WSMD-545 and CS7L-590 MS solar photovoltaic (PV) modules. The suggested algorithm is a concise and parameter-free approach that does not need the identification of any intrinsic parameter during the optimization stage. It is based on crystal structure generation by combining the basis and lattice point. The proposed algorithm is adopted to minimize the sum of the squares of the errors at the maximum power point, as well as the short circuit and open circuit points. Several runs are carried out to examine the V-I characteristics of the PV panels under consideration and the nature of the derived parameters. The parameters generated by the proposed technique offer the lowest error over several executions, indicating that it should be implemented in the present scenario. To validate the performance of the proposed approach, convergence curves of Mono PERC WSMD-545 and CS7L-590 MS PV modules obtained using the CrSA are compared with the convergence curves obtained using the recent optimization algorithms (OAs) in the literature. It has been observed that the proposed approach exhibited the fastest rate of convergence on each of the PV panels.

TCAD-Based Design and Optimization of Flexible Organic/Si Tandem Solar Cells

In order to surmount the Shockley–Queisser efficiency barrier of single-junction solar devices, tandem solar cells (TSCs) have shown a potential solution. Organic and Si materials can be promising candidates for the front and rear cells in TSCs due to their non-toxicity, cost-effectiveness, and possible complementary bandgap properties. This study researches a flexible two-terminal (2-T) organic/Si TSC through TCAD simulation. In the proposed configuration, the organic solar cell (OSC), with a photoactive optical bandgap of 1.78 eV, serves as the front cell, while the rear cell comprises a Si cell based on a thin 70 μm wafer, with a bandgap energy of 1.12 eV. The individual standalone front and bottom cells, upon calibration, demonstrate power conversion efficiencies (PCEs) of 11.11% and 22.69%, respectively. When integrated into a 2-T organic/Si monolithic TSC, the resultant tandem cell achieves a PCE of 20.03%, indicating the need for optimization of the top organic cell to beat the efficiency of the bottom Si cell. To enhance the performance of the OSC, some design ideas are presented. Firstly, the OSC is designed by omitting the organic hole transport layer (HTL). Consequently, through engineering the front contact work function, the PCE is enhanced. Moreover, the influence of varying the absorber defect density of the top cell on TSC performance is investigated. Reduced defect density led to an overall efficiency improvement of the tandem cell to 23.27%. Additionally, the effects of the variation of the absorber thicknesses of the top and rear cells on TSC performance metrics are explored. With the matching condition design, the tandem efficiency is enhanced to 27.60%, with VOC = 1.81 V and JSC = 19.28 mA/cm2. The presented simulation results intimate that the OSC/Si tandem design can find applications in wearable electronics due to their flexibility, environmentally friendly design, and high efficiency.

Annual degradation rates and soiling losses of photovoltaic systems composed of recent crystalline silicon technologies in temperate climate

AbstractThe purpose of this study is to investigate the annual degradation rates of photovoltaic (PV) systems composed of PV modules based on recent crystalline silicon (c‐Si) PV technologies. We investigated the annual degradation rates of four PV systems composed of different c‐Si PV technologies, comprising p‐type multi‐crystalline silicon with a passivated emitter rear cell, n‐type silicon heterojunction, p‐type single‐crystalline silicon (sc‐Si) with an aluminum back surface field, and n‐type (sc‐Si) solar cell technologies. These systems were located in Gunma Prefecture in Japan and were measured over 6 years. Furthermore, the effects of soiling on the annual degradation rates of these PV systems were examined by partially surface cleaning the PV arrays two times. The results obtained indicate that the apparent annual degradation rates of the PV strings before surface cleaning were 0.8, 1.6, 1.4, and 1.2%/year, respectively, because of optical losses due to dust particles. However, the inherent annual degradation rates of the PV strings after surface cleaning were 0.1, 0.6, 0.0, and 0.3%/year, respectively. These low degradation rates indicate that the PV systems composed of the recent c‐Si PV technologies all offered reasonably stable performance that was reduced by 3.6%, 5.5%, 7.3%, and 4.8%, respectively because of the effects of surface soiling, although the surfaces of the PV arrays had been washed by plentiful rainfall under their humid subtropical climatic operating conditions.

A novel phosphorus diffusion process for front-side P–N junction fabrication in PERC solar cells

P–N junction technology underlies photovoltaic conversion in passive emitter and rear cell (PERC) solar cells. Although the front-side phosphorus diffusion method for creating P-type PERC cells is well researched, avenues for innovation persist. We introduce a P–N junction fabrication technique for PERC solar cells via precisely controlling the surface doping concentration and junction depth. Through pressure modulation and carefully selected annealing duration at a defined temperature, the technique yields a P–N junction with a surface doping concentration of 2.37 × 1020 cm−3 and a junction depth of 0.29 μm on the front surface of PERC cells. Compared to conventional diffusion processes, our approach results in an average increase of 1.3 mV in open-circuit voltage, 20 mA in short-circuit current, and an efficiency gain of 0.05 %. The maximum efficiency achieved is 23.68 %, representing an improvement of 0.16 %.

Optimization of all-polymer/Sb2Se3 tandem solar cells for enhanced efficiency: a comprehensive TCAD modeling approach

Abstract This paper introduces a novel tandem configuration, utilizing an all-thin film all-polymer solar cell (all-PSC) with a wide bandgap of 1.76 eV for the front cell and Sb2Se3 with a narrow bandgap of 1.2 eV for the bottom cell. The design of this tandem is performed by comprehensive optoelectronic TCAD tools, essential for optimizing parameters across multiple layers to reach maximum power conversion efficiency (PCE). Experimental validation of models is conducted through calibration and validation against fabricated reference all-polymer and Sb2Se3 solar cells, yielding calibrated PCEs of approximately 10.1% and 10.5%, respectively. Subsequently, validated simulation models for both top and rear cells are utilized to design a 2-T all-polymer/Sb2Se3 tandem cell, which initially achieves a PCE of 10.91%. Through systematic optimization steps, including interface engineering and homojunction structure design, a remarkable PCE of 24.24% is achieved at the current matching point, showcasing the potential of our proposed tandem solar cell design. This study represents a significant advancement in the field of thin-film tandem solar cells, offering promising avenues for efficient and cost-effective photovoltaic technologies, particularly in applications requiring flexibility.

Investigating the impact of edge passivation on shingle solar modules

This work deals with solar modules made from rectangular-shaped solar cell strips, so-called shingles, that are interconnected by overlapping one with another. For the fabrication of such modules, host solar cells are cut into several shingles resulting in unpassivated shingle cell edges and relevant recombination losses. As discussed in this work based on simulations, quantifying these losses on module level is not straightforward and is ideally done by referring to the pseudo fill factor pFF. In this context, it is shown that by passivating the cut edges of the shingles by depositing a dielectric layer, a significant pFF increase can be achieved both on shingle as well as on module level. Considering the highest respective pFF value found for modules with and without edge passivation, an increase of ΔpFF = 0.5%abs is reached. At the same time, no significant compromise of the interconnection quality is observed. These results are obtained for monofacial passivated emitter and rear cell (PERC) shingles. In short, this work is the first comprehensive analysis of experimental data on module level in the context of edge passivation. It demonstrates that the deposition of a dielectric passivation layer at the shingle's edges can boost pFF of shingle solar modules, while the current transit between the busbars of jointed shingles is not significantly hindered.

Method and Equipment for Reducing the Efficiency Degradation of Monocrystalline Passivated Emitter and Rear Cells

Infrared soldering as a step in module encapsulation, which would cause light-induced degradation (LID) and light- and elevated-temperature-induced degradation (LeTID) effects on solar cells, may cause efficiency mixing among solar cells that were originally in the same grade within the module after soldering. Furthermore, the problem of bright and dark regions would appear, which would result in a decrease in the CTM value. Current injection is considered to be one of the effective methods to solve the above problem. However, after the current injection treatment, there is still a 10% probability of the appearance of bright and dark regions in modules. In this work, we first adopted the conventional current injection process in monocrystalline passivated emitter and rear cells (PERCs). The effects of injected currents, temperature and time were systematically optimized, and cells with or without the current injection under the optimal parameters were illuminated with 1 sun at 85 °C for 25 h. Secondly, a piece of equipment was developed to further stabilize the performance of solar cells and improve the CTM value. The results showed that the best current injection parameters were a temperature of 185 °C, an injected current of 11 A and an injection time of 770 s. Compared with the cells without any pretreatment, the relative changes in the η, Voc, Isc and FF of the cells pretreated with the optimal conditions mentioned above were 0.23%, 0.08%, 0.02% and 0.08% larger, respectively, after 25 h of degradation. Then, solar cells processed by current injection were processed with our equipment, and the probability of a problem occurring was reduced from 10% to 2%. Meanwhile, the CTM value increased by 0.4%. Finally, a balance mechanism between H0 and H0-X has been proposed to explain the mechanism of the equipment.

Field performance analysis of solar cell designs

This study analyzes the field performance of various solar cell designs. Most research and development efforts concerning solar cells aim to increase their efficiency or power under standard test conditions (STC). However, conducting an actual field performance analysis is crucial because of the various ambient conditions present in the field, including temperature, irradiance, PV system installation, and albedo. These conditions can result in different performance results compared to STC. This study compares and analyzes case studies to assess field performance. One particular case study compares the field performance of monofacial modules with a monofacial passivated emitter and rear cell (PERC) and bifacial PERC at a carport system in the ambient conditions of the Korean Peninsula during summer and winter. The module material properties (white EVA and white backsheet) can impact module performance owing to the transmittance spectra at longer wavelengths. Certain transmittance values also contribute to the bifaciality number. Although the monofacial cell demonstrates better STC results, the field performance of the bifacial cell is superior in terms of energy yield and cost-effectiveness. Therefore, this study highlights the importance of considering the field performance (energy yield), in addition to STC, when designing solar cells and modules.

Performance optimization of PERC solar cells based on laser ablation forming local contact on the rear

Abstract To improve the photoelectric conversion efficiency (η) of the solar cell, a green wavelength (532 nm) laser source in a nanosecond range was used to ablate the passivated emitter and rear cell (PERC) to form the contact holes. If the laser ablation hole opening process was not set properly, the diameter or the external expansion of holes would be too large, causing the decline of the PERC performance. The Gaussian distribution of the laser is regulated by the output power (P o) and the repetition frequency (f rep) of the incident pulse laser, so that the optimized morphology of holes is obtained on the back of the PERC solar cells. After the contact holes are screen printed by the aluminum paste, the local back surface field is finally formed. The experimental results showed that the outward expansion decreases obviously with the increase of laser P o. Second, the spacing of the holes decreases with the increase of the laser f rep. It was found that under the laser P o of 33.0 W and f rep of 1,400 kHz, the η of the industrial PERC solar cells was the highest. The Quokka simulations indicated that small outward expansion, small diameter, and long spacing of holes would further decrease the recombination parameter in the rear surface. With the optimized morphology of contact holes and the low contact resistance, the PERC cell’s calculated V oc and η improvements were 6.5 mV and 0.48%, respectively, which was verified with experimental findings.

Proposal and design of organic/CIGS tandem solar cell: Unveiling optoelectronic approaches for enhanced photovoltaic performance

Solar cells are promising devices for converting sunlight into electrical energy. Tandem solar devices, which combine multiple sub cells with complementary absorption spectra, offer a potential strategy to enhance the overall power conversion efficiency (PCE). In this work, the design and performance of organic/CIGS tandem solar devices are investigated. The initial tandem cell comprises two sub cells, namely an organic-based PM6:m-DTC-2 F top cell and CIGS bottom cell. The organic and CIGS cells show a PCE of 12.20% and 20.10%, respectively, where the initial results are based on calibrated cells reproduced from experimental studies. Accordingly, the initial tandem PM6:m-DTC-2 F/CIGS cell shows a PCE of 22.75%. The study focuses on optimizing the PCE via different approaches. Firstly, through the exploration of different hole transport layers (HTLs) of the front cell. Secondly, by investigating the matched current condition between the front and rear cells. Moreover, the doping effect of the CIGS film is investigated. Finally, optimization of the defect concentrations in the absorbers is introduced. These optimizations result in open circuit voltage (Voc) of 1.89 V with short circuit current (Jsc) of 17.55 mA/cm2, and a fill factor (FF) of 82.79%. Consequently, the PCE of the optimized tandem cell is further enhanced to 27.46%. Further, the stability of the proposed tandem cell is evaluated under varying temperatures, and its composition of flexible materials makes it a promising candidate for wearable applications.

Passivated Emitter and Rear Cell (PERC) Assessment and Potential in Palestine

Palestine has limited energy sources and must import different fuels from neighboring countries, hence renewable energy sources like solar energy are necessary. One of the most important and promising clean renewable energy sources available today that also helps cut expenses and effort is solar energy. Solar energy is captured and stored by solar panels. Solar panels come in a wide variety now, and new kinds are always being developed to maximize solar energy absorption, require the least amount of maintenance, and endure a longer time. This study will compare the performance of the polycrystalline solar cell unit and the PERC unit, both of which will be impacted by Palestine's environment, by conducting an experimental investigation into the behavior of the unit. The PERC panel's temperature was lower than the polycrystalline panel's because of the addition of a heat-reflecting layer, which increased the PERC panel's efficiency. The efficiencies of the two panels were compared at the same level of solar radiation. It has been demonstrated that PERC efficiency is higher when solar radiation is the same. The solar energy absorbed in the PERC panel actually increases because of the reflective coating that helps the PERC cell to optimize its benefit from the sun's radiation. When polycrystalline and PERC panels were compared, the former produced more electricity per unit of area