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A Computational Protocol for Precise Prediction of Dye-Sensitized Solar Cell Performance
摘要： Numerous organic dyes have been developed for dye-sensitized solar cells (DSSCs). However, theoretical screening has not played the due role in designing new dyes. It is mainly attributed that there is rarely quantitative calculation and the inaccurate estimated values for short-circuit current density (JSC) and open-circuit photovoltage (VOC), especially for VOC. In this work, VOC is theoretically predicted by two different models for three D-π-A organic dyes (1, 2, and 3) with the same π bridge and acceptor as well as different donors. Although there is slight deviation for their structures, their properties are successfully differentiated by accurate quantitative calculations. Dimethoxybenzene substituted indoline is more suitable to be donor than methoxy substituted triphenylamine and methyl substituted indoline when it combines with 8H-thieno[2′,3′:4,5]thieno[3,2-b]thieno[2,3-d]pyrrole (TTP) as π bridge and cyanoacrylic acid as acceptor. The properties of donor not only are related with the core group but also are determined by the substituted group. Less than 10% deviation between theoretical and experimental results is an insurance to perform the reasonable prediction for photocurrent-photovoltage.
关键词： Short-circuit current density,Organic dyes,Computational protocol,Open-circuit photovoltage,Theoretical screening,Dye-sensitized solar cells
更新于2025-09-16 10:30:52
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[IEEE 2019 International Conference on Electrical, Communication, and Computer Engineering (ICECCE) - Swat, Pakistan (2019.7.24-2019.7.25)] 2019 International Conference on Electrical, Communication, and Computer Engineering (ICECCE) - Degradation of PhotoVoltaic (PV) Panel Performance due to Shading Effect- Case of Pakistan
摘要： Pakistan is geographically suitable for the installation of Photovoltaic (PV) cells to produce electricity. Pakistan covers the maximum of its land where sunny days prevail throughout the year. The energy produced from these panels can be affectively distributed throughout and excess of it can be provided to the nearby grid. The population of Pakistan is tremendously enhancing due to which construction of buildings is growing up causing shading that harmfully affects the performance of PV panel. The production of electricity from the renewable energy sources is surely considerate and friendly. No detrimental chemicals are given out making the environment pollution free. The performance of the PV cells solely depends upon many factors i.e. intensity of light, shading, temperature, dust and cells configuration. In this paper the shading effect over the PV cells and how to nullify its substandard effect on the performance of PV panel is overviewed. It was accounted that the depletion in the maximum output power & short circuit current was 34% and 40% respectively due to the 30% shading strength in mono crystalline PV panel. For the better efficiency of the PV array, modules are coupled in the series and parallel configuration to enhance the voltage & current respectively. Bypass diodes are instigated to overwhelm the shading effect.
关键词： PV panel,shading effect,Short Circuit Current,Renewable source of energy,Maximum Power Output
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) - Macau, China (2019.11.3-2019.11.8)] 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) - A Robust Laser-Inertial Odometry and Mapping Method for Large-Scale Highway Environments
摘要： This paper proposes a new fast technique, in which the slope of a photovoltaic (PV) inverter current is utilized to predict if the current is expected to exceed its rated value due to any grid faults. Two applications of this technique are demonstrated. In jurisdictions where grid codes require distributed generators (DGs) to disconnect after a fault occurrence, such as in Ontario, Canada, this technique is utilized to rapidly disconnect the PV solar system even before the inverter short circuit current actually exceeds the rated current of the inverter, thereby obviating the problem of any adverse short circuit current contribution into the grid. However, in regions where grid codes require DGs to stay connected and provide grid support, such as low-voltage ride through, this technique can be used to rapidly and autonomously transform the PV solar farm into a dynamic reactive power compensator STATCOM (termed PV-STATCOM) for providing voltage support function. In this paper, the PV-STATCOM is used to stabilize a critical induction motor load in the vicinity of the solar farm, which would have otherwise become unstable due to the grid fault. PSCAD-based simulation studies are performed on a realistic distribution network to demonstrate the effectiveness of this technique.
关键词： STATCOM,Distributed generator (DG),inverter,flexible AC transmission system (FACTS),protection,short circuit current,PV-STATCOM,photovoltaic (PV) systems
更新于2025-09-16 10:30:52
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Simulation of a-Si:H/c-Si heterojunction solar cells: From planar junction to local junction
摘要： In order to obtain higher conversion efficiency and reduce production cost for the HIT (Heterojunction with Intrinsic Thin film) solar cell was investigated. The performance hydrogenated amorphous silicon/crystalline silicon (a-Si:H/c-Si) based heterojunction solar cells, HACL solar cell was compared with that of the HIT and HACD (Heterojunction of Amorphous silicon and Crystalline silicon with Diffused junction) solar cells. The simulated results indicated that a-Si:H layer can bring about much absorption loss. The conversion efficiency and the short-circuit current density of the HACL cell can reach 28.18% and 43.06 mA/cm2, respectively, and are higher than that of the HIT and HACD solar cells. The main reasons for the great improvement are (1) to reduce optical absorption loss of a-Si:H and (2) to reduce photocarrier recombination for the HACL cell. The double-side local junction is very suited for the bifacial solar cells. For a HACL cell with n-type or p type c-Si base, all n-type or p-type c-Si passivating structure can decrease the consumption of rare materials since the transparent conductive oxide (TCO) can be free in this structure. It is concluded that the HACL solar cell is a promising structure for high efficiency and low cost.
关键词： a-Si:H/c-Si heterojunction,silicon solar cell,local junction,short-circuit current
更新于2025-09-12 10:27:22
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Description of short circuit current of outdoor photovoltaic modules by multiple regression analysis under various solar irradiance levels
摘要： Short-circuit current (ISC) values of test photovoltaic (PV) modules, i.e., multi-crystalline silicon, heterostructure-with-intrinsic-thin-layer, single-crystalline silicon back-contact, CuInSe2 (CIS), and CdTe modules, are descripted using multiple regression analysis based on environmental factors (solar irradiance, average photon energy (APE), and module temperature (Tmod)) under several solar irradiance levels. The APE is an index of the solar spectral irradiance distribution. PV module irradiance sensor is used to investigate simultaneous solar irradiance (PVMS), single-crystalline silicon PV module, (IrrTPVMS). It is disclosed that ISC is primarily determined by IrrTPVMS. Error between the estimated ISC and measured ISC of test PV modules is investigated. Consequently, precise ISC description (low error) is obtained when IrrTPVMS is utilized. The more precise description of the ISC for CIS and CdTe PV modules, having the bandgap (Eg) different from PVMS, is realized when adding APE environment factor even under low IrrTPVMS ((cid:1)0 kW/m2), accumulated on both sunny day and cloudy day suggesting the enhancement of investigation opportunity. This is because APE minimizes spectral mismatch error caused by Eg difference between PVMS and test PV module. Moreover, the precision of ISC description is further increased under enhanced IrrTPVMS of (cid:1)0.5 kW/m2 (on sunny day) due to stable solar irradiance.
关键词： Multiple regression analysis,Solar irradiance levels,PV module irradiance sensor,Short-circuit current
更新于2025-09-12 10:27:22
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Conducting polyaniline decorated in-situ poled Ferrite nanorod-PVDF based nanocomposite as piezoelectric energy harvester
摘要： PVDF-metal oxide based piezo-nanocomposite is an promising substitute of flexible nanogenerator. Herein, a ternary nanocomposite system Zinc Ferrite nanorod/ Polyvinylidenefluoride (PVDF)/ Polyaniline (PANI) nanochains was presented as alternative energy harvesting material. The inherent problem of low short-circuit current and high internal resistance of the nanocomposite was minimised by introducing a third phase cost-effective conducting supplementary filler, PANI nanochain.PANI assist to overcome the local dielectric dissimilarity by easy formation of conduction pathways via decolalization of π-electrons present in the benzene ring and reduce the internal resistance of composite. Besides, it serves the role of dispersing agent by floating nanofillers throughout the volume and improves the homogeneity of filler distribution. Additionally, PANI reinforces composite with respect to stress accumulation and modulates the release behaviour by entangling with nanofillers by means of Vander Waals force and helps to stabilize the polar PVDF. This lead to an improvement in electro-mechanical response and piezo-response behaviour of nanocomposite. The nanocomposite exhibits a ~42 V ac open circuit voltage and short-circuit current density ～0.85 μA/cm2with an overall increase in power density 35% compare to its binary metal-oxide/PVDF nanocomposite counterpart in response to single finger tapping and releasing. The generated power was utilizedto illuminate twenty six number of red LEDs without any external energy storage unit. Also, the nanocomposite could charge up acommercial capacitor (10μF) within 115 s which can be used for alternative powersouce in self-powered devices and sensors.
关键词： PANI,capacitor charging,short-circuit current,PVDF-metal oxide based nanocomposite,conduction pathway,alternative energy harvesting
更新于2025-09-12 10:27:22
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Stilbene Based Organic Dye as Efficient Sensitizer for NLO and Dye-Sensitized Solar Cells: A First Principle Study
摘要： In this study, we have designed five different Stilbene based dyes as efficient sensitizers for Nonlinear Optical Properties (NLO) and Dye-Sensitized Solar Cells (DSSCs). Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) have used to investigate molecular properties, in order to influence and performance of the dye sensitizer in the DSSCs. The theoretical result indicates that the HOMO and LUMO energy levels of this dye can be ensured a positive effect on the process of photoelectron injection into semiconductor surface and dye regeneration by the electrolyte. The solar energy conversion efficiency, effective key parameters in influence with the Short-Circuit Current Density (JSC), Light Harvesting Efficiency (LHE) and Electron injection driving force (?Ginject) were discussed. The Stilbene-based dyes can be used as a potential sensitizer for photoelectron injection into the semiconductor surface due to its best electronic structure and optical properties of the good photovoltaic parameters.
关键词： Reorganization energy,Light Harvesting Efficiency,Driving force,Short-Circuit Current Density,Dye sensitizer
更新于2025-09-12 10:27:22
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Acceptor Gradient Polymer Donors for Non-Fullerene Organic Solar Cells
摘要： In organic solar cells, maximizing the open-circuit voltage (VOC) via minimization of the ionization energy or electron a?nity o?sets of the blended donor and acceptor often comes at the expense of achieving a considerable amount of short-circuit current (JSC). To explore a hypothesis for the design of materials that may circumvent this tradeo?, eight structurally similar polymers were synthesized consisting of a ?uorinated/non-?uorinated benzothiadiazole (BTDF/BTD) strong acceptor moiety, a thiophene ester (TE) weak acceptor, and various donor units composed of bithiophene (T2), biEDOT, and benzodithiophene (BDT) to form six acceptor gradient and two nongradient polymers. The acceptor gradient motif was designed and theorized to induce more facile exciton dissociation in low driving force solar cells by creating a further separated intramolecular charge-transfer state between the strong BTD acceptor and various donor units through a bridging TE component. Solar cells were fabricated using the eight polymers blended with phenyl-C71-butyric-acid methyl ester (PC71BM) to reveal two top performing isomeric polymers, T2-BTDF-(TE2) and TE2-BTDF-(T2), which were further tested with several non-fullerene acceptors (NFAs): EH-IDTBR, ITIC, and ITIC-4F. In order to fabricate optimally performing solar cells, a 0.2 eV ionization energy o?set was found to be essential or the short-circuit current of the NFA cells diminished dramatically. Ultimately, optimized NFA solar cells were fabricated using ITIC-4F paired with each of the top performing polymers to produce an average PCE of 7.3% for TE2-BTDF-(T2) (nongradient) and 3.6% for T2-BTDF-(TE2) (gradient). The acceptor gradient e?ect was not shown to reduce the amount of charge recombination in NFA solar cells mainly due to the inability to fabricate solar cells, with minimal ionization energy or electron a?nity o?sets along with morphological complications. This work stresses the importance of acquiring accurate ionization energies and electron a?nities when characterizing solar cell energetics, as di?erences as small as 0.1 eV in the o?sets can make a signi?cant impact on overall charge collection.
关键词： acceptor gradient polymers,open-circuit voltage,electron affinity offset,charge recombination,organic solar cells,non-fullerene acceptors,ionization energy offset,short-circuit current
更新于2025-09-11 14:15:04
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Influence of Temperature on the Output Parameters of a Photovoltaic Module Based on Amorphous Hydrogenated Silicon
摘要： The light load current-voltage characteristics of a solar photovoltaic module based on amorphous hydrogenated silicon have been studied at different temperatures under conditions of natural solar illumination (Рrad = 870 ± 10 W/m2). It has been found that the temperature dependence of the photocurrent has two slopes due to a change in the generation–recombination mechanism. The increase in the value of the short-circuit current with increasing temperature of the photovoltaic module is explained by a rise in the drift lengths of minority charge carriers due to an increase in the lifetime of minority carriers. In this case, the quasi Fermi level shifts to the conduction band, and the concentration of recombination centers decreases due to recharging of defective levels (D0 → D–). The decrease in the value of the open-circuit voltage with increasing temperature is explained by the exponential increase in the reverse saturation current and decrease in the band gap of the semiconductor. It has been found that the fill factor (FF) of the current–voltage characteristics decreases with increasing temperature, most likely due to a decrease in the shunt resistance (Rsh), which connects parallel to the p–n junction, consists of parasitic resistances, and leads to an increase in leakage currents. The temperature coefficient of the maximum output power has a positive value in the range of 320–332 K, i.e., increases with temperature. It has been revealed that the values of shunt and series resistance decrease with increasing temperature. A large loss of power output (up to 19%) has been observed on the series resistance of the solar photovoltaic module in the temperature range of 320–332 K. With increasing temperature, the loss of generated power on the shunt resistance grows sublinearly. The efficiency of the solar photovoltaic module decreases from 7.95 to 7.65% and has a coefficient of temperature dependence of efficiency, which decreases from ≈ –0.029%/K to ≈ –0.046%/K.
关键词： shunt resistance,series resistance,efficiency,temperature,open-circuit voltage,fill factor,solar photovoltaic module,amorphous hydrogenated silicon,short-circuit current
更新于2025-09-11 14:15:04
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Photovoltaic output parameters of a mono-crystalline silicon solar cell with non-uniform horizontal temperature distributions
摘要： Temperature inhomogeneity occurs frequently in the application of photovoltaic devices. In the present study, the effect of nonuniform horizontal temperature distributions on the photovoltaic output parameters of a monocrystalline silicon solar cell including short-circuit current, open-circuit voltage, output power, etc. was investigated. A laser beam irradiated on the center of the cell surface was used to obtain nonuniform temperature distributions. The results show that the higher initial temperature region of the solar cell absorbs more heat energy and achieves higher temperature than the lower initial temperature region after exposure to the same sunlight. Meanwhile, the photovoltaic parameters vary with the temperature difference between the center and edge of the solar cell. The maximum output power decreases exponentially with the temperature difference. The output power under an external load resistance of 1 X is almost inversely proportional to the temperature difference. According to the experimental results, when the temperature difference between the center and edge of the solar cell changes from 0 K to 60 K, the open-circuit voltage, maximum output power, output current, and power under external load resistance of 1 X would decrease by 4.8%, 4.8%, 5.1%, and 9.8%, respectively. The photovoltaic ef?ciency decreases when the temperature distribution is nonuniform.
关键词： nonuniform temperature distributions,photovoltaic output parameters,output power,open-circuit voltage,monocrystalline silicon solar cell,short-circuit current
更新于2025-09-11 14:15:04