The Experts below are selected from a list of 4422 Experts worldwide ranked by ideXlab platform

Rudolf Hezel - One of the best experts on this subject based on the ideXlab platform.

  • optimised antireflection coatings for planar silicon solar cells using remote pecvd silicon nitride and porous silicon dioxide
    Progress in Photovoltaics, 1999
    Co-Authors: Henning Nagel, Armin G Aberle, Rudolf Hezel
    Abstract:

    Silicon nitride (SiN) films fabricated by remote plasma-enhanced chemical vapour deposition (RPECVD) have recently been shown to provide an excellent electronic passivation of silicon surfaces. This property, in combination with its large refractive index, makes RPECVD SiN an ideal candidate for a surface-passivating antireflection coating on silicon solar cells. A major problem of these films, however, is the fact that the extinction coefficient increases with increasing refractive index. Hence, a careful optimisation of RPECVD SiN based antireflection coatings on silicon solar cells must consider the light absorption within the films. Optimal optical performance of silicon solar cells in air is obtained if the RPECVD SiN films are combined with a medium with a refractive index below 1·46, such as porous SiO2. In this study, the dispersion of the refractive indices and the extinction coefficients of RPECVD SiN, porous SiO2, and several other relevant materials (MgF2, TiOx, ZnS, B270 Crown Glass, soda lime Glass, ethylene vinyl acetate and resin as used in commercial photovoltaic modules) are experimentally determined. Based on these data, the short-circuit currents of planar silicon solar cells covered by RPECVD SiN and/or porous SiO2 single- and multi-layer antireflection coatings are numerically maximised for Glass-encapsulated as well as non-encapsulated operating conditions. The porous SiO2/RPECVD SiN-based antireflection coatings optimised for these applications are shown to be universally suited for silicon solar cells, regardless of the internal blue or red response of the cells. Copyright © 1999 John Wiley & Sons, Ltd.

L Thomas - One of the best experts on this subject based on the ideXlab platform.

  • comprehensive simulation and optimization of porous sio2 antireflective coating to improve Glass solar transmittance for solar energy applications
    Solar Energy Materials and Solar Cells, 2018
    Co-Authors: Antoine Grosjean, Audrey Soumglaude, Pierre Neveu, L Thomas
    Abstract:

    Abstract In many areas which call for solar radiation harvesting, from buildings to solar power plants, all manners of windows and protective Glass envelopes are required. A high transmission of solar light through Glass is therefore mandatory, mostly in the visible range for lighting purposes and also in the near infrared range for power generation. For this purpose, antireflective coatings (ARCs) are deposited on Glass surfaces to avoid parasitic reflection and increase transmission of the incident solar light. Porous SiO 2 or compact MgF 2 have been identified in the literature as good antireflective materials for Glass due to their low refractive index. The total solar power transmitted through coated Glass is determined by the wavelength-dependent optical properties (spectral complex refractive index) of both the Glass and the ARC deposited on it. For many optical applications other than solar, the Glass industry takes into account the impact of the variation with wavelength of the Glass refractive index, represented by the Abbe number, on its transmittance. For solar applications however, in most reported studies on ARCs for solar Glass, the optimization of the ARC in terms of porosity and thickness is done by considering the refractive index of the Glass as a single value independent of wavelength. This approximation can affect the accuracy and pertinence of the solar ARC optimization. In this work, we therefore propose to join these two approaches by including the Glass refractive index variation with wavelength in the optimization of a typical solar ARC, for a large catalog of Glasses available in the industry. To achieve this goal, we simulated and optimized with a stochastic algorithm the solar antireflective properties of a porous SiO 2 coating on 24 different Glasses. We studied the impact on their solar transmittance of the Glass refractive index variation with wavelength, the incident solar spectrum (Direct + Circumsolar or Global Tilt), the incidence angle and the Glass solar absorptance. Glasses with low refractive indices and high Abbe numbers were found to be necessary to ensure high solar transmittance. Such properties are met in Crown Glass such as FK ® , PK ® or BK ® .

Henning Nagel - One of the best experts on this subject based on the ideXlab platform.

  • optimised antireflection coatings for planar silicon solar cells using remote pecvd silicon nitride and porous silicon dioxide
    Progress in Photovoltaics, 1999
    Co-Authors: Henning Nagel, Armin G Aberle, Rudolf Hezel
    Abstract:

    Silicon nitride (SiN) films fabricated by remote plasma-enhanced chemical vapour deposition (RPECVD) have recently been shown to provide an excellent electronic passivation of silicon surfaces. This property, in combination with its large refractive index, makes RPECVD SiN an ideal candidate for a surface-passivating antireflection coating on silicon solar cells. A major problem of these films, however, is the fact that the extinction coefficient increases with increasing refractive index. Hence, a careful optimisation of RPECVD SiN based antireflection coatings on silicon solar cells must consider the light absorption within the films. Optimal optical performance of silicon solar cells in air is obtained if the RPECVD SiN films are combined with a medium with a refractive index below 1·46, such as porous SiO2. In this study, the dispersion of the refractive indices and the extinction coefficients of RPECVD SiN, porous SiO2, and several other relevant materials (MgF2, TiOx, ZnS, B270 Crown Glass, soda lime Glass, ethylene vinyl acetate and resin as used in commercial photovoltaic modules) are experimentally determined. Based on these data, the short-circuit currents of planar silicon solar cells covered by RPECVD SiN and/or porous SiO2 single- and multi-layer antireflection coatings are numerically maximised for Glass-encapsulated as well as non-encapsulated operating conditions. The porous SiO2/RPECVD SiN-based antireflection coatings optimised for these applications are shown to be universally suited for silicon solar cells, regardless of the internal blue or red response of the cells. Copyright © 1999 John Wiley & Sons, Ltd.

Antoine Grosjean - One of the best experts on this subject based on the ideXlab platform.

  • comprehensive simulation and optimization of porous sio2 antireflective coating to improve Glass solar transmittance for solar energy applications
    Solar Energy Materials and Solar Cells, 2018
    Co-Authors: Antoine Grosjean, Audrey Soumglaude, Pierre Neveu, L Thomas
    Abstract:

    Abstract In many areas which call for solar radiation harvesting, from buildings to solar power plants, all manners of windows and protective Glass envelopes are required. A high transmission of solar light through Glass is therefore mandatory, mostly in the visible range for lighting purposes and also in the near infrared range for power generation. For this purpose, antireflective coatings (ARCs) are deposited on Glass surfaces to avoid parasitic reflection and increase transmission of the incident solar light. Porous SiO 2 or compact MgF 2 have been identified in the literature as good antireflective materials for Glass due to their low refractive index. The total solar power transmitted through coated Glass is determined by the wavelength-dependent optical properties (spectral complex refractive index) of both the Glass and the ARC deposited on it. For many optical applications other than solar, the Glass industry takes into account the impact of the variation with wavelength of the Glass refractive index, represented by the Abbe number, on its transmittance. For solar applications however, in most reported studies on ARCs for solar Glass, the optimization of the ARC in terms of porosity and thickness is done by considering the refractive index of the Glass as a single value independent of wavelength. This approximation can affect the accuracy and pertinence of the solar ARC optimization. In this work, we therefore propose to join these two approaches by including the Glass refractive index variation with wavelength in the optimization of a typical solar ARC, for a large catalog of Glasses available in the industry. To achieve this goal, we simulated and optimized with a stochastic algorithm the solar antireflective properties of a porous SiO 2 coating on 24 different Glasses. We studied the impact on their solar transmittance of the Glass refractive index variation with wavelength, the incident solar spectrum (Direct + Circumsolar or Global Tilt), the incidence angle and the Glass solar absorptance. Glasses with low refractive indices and high Abbe numbers were found to be necessary to ensure high solar transmittance. Such properties are met in Crown Glass such as FK ® , PK ® or BK ® .

Kwok Wa Leung - One of the best experts on this subject based on the ideXlab platform.

  • Transparent dielectric resonator antennas for optical applications
    IEEE Transactions on Antennas and Propagation, 2010
    Co-Authors: Eng Hock Lim, Kwok Wa Leung
    Abstract:

    The transparent dielectric resonator antenna (DRA) for optical applications is proposed for the first time. For demonstration, a dual function transparent hemispherical DRA made of Borosilicate Crown Glass (Pyrex) is investigated. The dual function DRA simultaneously works as an antenna and a focusing lens for an underlaid solar cell. The system is very compact because no extra footprint is needed for the solar cell. A conformal strip is used to excite the hemispherical DRA in its fundamental broadside TE111 mode. Due to the focusing effect of the DRA, higher voltage and current outputs of the solar cell can be obtained. In this paper, the transparent rectangular DRA was also studied, and it was found that the rectangular DRA does not provide the focusing function. It was also found that the proposed transparent DRAs can provide a higher gain ( ~ 4 dBi) than for the state-of-the-art transparent microstrip antennas ( ~ -5 dBi to 0 dBi). The reflection coefficients, input impedances, antenna gains, and radiation patterns of the two transparent DRAs are studied, and reasonable agreement between the simulated and measured results was observed. The proposed configurations can potentially be used for applications that need a self-sustaining power.