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In this paper, we analysed and implement clear sky and array performance models to achieve maximum electrical energy produced from the photovoltaic (PV) panel. The selected models just not only include location dependent parameters but also include environmental factors such as Linke Turbidity (include aerosols, absorption due to assorted gases, Rayleigh scattering), cloud cover, albedo, perceptible water vapour. 250 W PV panel was used as a reference to check the output electrical energy in a given location by inputting the latitude and longitude of a location. It is concluded that 27° facing south is the optimized tilt angle for every locations having latitude at north direction and longitude at east direction. By taking the example of location Nagpur India (21.14° N, 79.08° E), a difference of only 0.35 % is reported when comparing the computed electrical energy with actual electrical energy that have been acquired by using pyranometers, pyrheliometers and illuminance meters installed by the National Renewable Energy Laboratory (NREL). So, a good approximation of electrical energy can be computed by combining clear sky and array performance models.

Antireflection coatings (ARCs) on an optical substrate appear to be highly effective for reducing reflectance for optical and photovoltaic (PV) panel applications. In this perspective, we have prepared and investigated the performance of silica nanoparticles (SNPs) ARC through a sol–gel process for the PV module applications. The ∼160-nm-thick sol–gel prepared SNPs have been coated on a glass substrate using the spin coating technique. The further vapor-phase treatment of hexamethyldisilazane (HMDS) on silica-coated glass results in contamination-resistant due to the existence of trimethylsilyl groups. The resultant-coated glass exhibits improvement in transmission by ∼3 % while reducing the refractive index value up to 1.17. The solar cell tested undercoated glass notifies the increase in current density of 34.24 to 35.17 mA / cm2 and improves the overall efficiency up to 3.13% as compared to the untreated glass. The results obtained in our study suggest an important future direction for the use of HMDS-treated SNPs in an outdoor PV module and solar collector applications.

Numerical simulation and experimental techniques were used to investigate lithium fluoride (LiFx) films as an electron extraction layer for the application of silicon heterojunction (SHJ) solar cells, with a focus on the paths toward excellent surface passivation and superior efficiency. The presence of a 7 nm thick hydrogenated intrinsic amorphous silicon (a-Si:H(i)) passivation layer along with thermally evaporated 4 nm thick LiFx resulted in outstanding passivation properties and suppresses the recombination of carriers. As a result, minority carrier lifetime (τ eff) as well as implied open-circuit voltage (iVoc) reached up 933 μs and iVoc of 734 mV, accordingly at 120 °C annealing temperature. A detailed simulated study was performed for the complete LiFx based SHJ solar cells to achieve superior efficiency. Optimized performance of SHJ solar cells using a LiFx layer thickness of 4 nm with energy bandgap (Eg) of 10.9 eV and the work function of 3.9 eV was shown as: Voc = 745.7 mV, Jsc = 38.21 mA cm−2, FF = 82.17%, and η = 23.41%. Generally, our work offers an improved understanding of the passivation layer, electron extraction layer, and their combined effects on SHJ solar cells via simulation.

The efficiency of silicon heterojunction solar cells is limited by various factors including low surface passivation, parasitic absorption, and recombination losses. Herein, the surface passivation quality of crystalline silicon solar cells is improved by a hybrid passivation structure including a silicon heterojunction contact at the front side and a stack of tunneling oxide with n-type nano-crystalline silicon oxide (nc-SiOx(n)) passivating contact at the rear side. A passivation contact with thin silicon oxide (SiO2) and poly-silicon was previously proposed to enhance the rear surface passivation. In our study, the poly-silicon layer is swapped with the nc-SiOx(n) layer to improve the effective surface passivation, electrical properties, recombination losses, and carrier selectivity. The hybrid passivation structure shows significant passivation improvement with lifetime (τeff) of 2696 μs and implied open-circuit voltage (i-Voc) of 735 mV as compared with both-sides traditional silicon heterojunction (1650 μs, 719 mV) and tunneling passivation contact (2146 μs, 725 mV). The hybrid solar cell shows a potential performance as; open circuit voltage (Voc) = 724 mV, short circuit current (Jsc) = 38.95 mA/cm2, fill factor (FF) of 75.9%, efficiency (η) = 21.4%. However, there is room to further improve the overall cell performance.

An automatic sedimentary microfacies identification technique is developed based on the deep process neural network (DPNN), which consist several neurons and general non-time-varying neurons arranged in a certain topological structure. In this technique, the features of the shape and amplitude of logging curves are considered to form the category outputs. Combined with the deep learning theory, the diversity of the process features of logging curves and the complexity of combined features of multiple geophysical logging information are considered, and DPNN is created through the stacked superimposition of deep belief network and BP classifier. The technique maintains the structure and information relevance of process signal data and can characterize the distribution features of logging curves automatically, and classify the process signals directly. The theoretical nature and performance of the improved algorithm is tested and validated by some field examples.

Silicon heterojunction solar cells have been gaining remarkable attention in the photovoltaic industry in recent years owing to their low temperature coefficient and high efficiency. This study aimed to maximize the short circuit current density (Jsc), which is directly correlated with the absorbance of the solar cells. An advanced ray tracking model and hall effect measurement was used to improve the optical properties of Al2O3/ITO as a double-layered anti-reflection coating (DLARC) on the solar cell. RF/DC power sputtering system was used to deposit ITO layer, while atomic layer deposition was used to deposit Al2O3 on ITO to create a DLARC. An average decrease in reflection from 9.33% to 4.74% and enhancement in EQE from 76.89% to 84.34% were observed for the DLARC in the wavelength spectrum at 300–1100 nm. It also exhibited a higher Jsc value of 41.13 mA/cm2 and maximum conversion efficiency of 21.6%. The findings of both simulation and experiments showed that the Al2O3/ITO DLARC has better anti-reflection properties than a single-layer ITO coating.