Premium
Sunrise to sunset optimization of thin film antireflective coatings for encapsulated, planar silicon solar cells
Author(s) -
Boden S. A.,
Bagnall D. M.
Publication year - 2009
Publication title -
progress in photovoltaics: research and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.286
H-Index - 131
eISSN - 1099-159X
pISSN - 1062-7995
DOI - 10.1002/pip.884
Subject(s) - anti reflective coating , materials science , optoelectronics , optics , transmittance , thin film , quantum efficiency , silicon , layer (electronics) , nanotechnology , physics
We present an approach for the optimization of thin film antireflective coatings for encapsulated planar silicon solar cells in which the variations in the incident spectra and angle of incidence (AOI) over a typical day are fully considered. Both the angular and wavelength dependences of the reflectance from the surface, absorptance within the coating, and transmittance into the device are calculated for both single‐ and double‐layer antireflection coatings with and without thin silicon oxide passivation layers. These data are then combined with spectral data as a function of time of day and internal quantum efficiency to estimate the average short‐circuit current produced by a fixed solar cell during a day. This is then used as a figure of merit for the optimization of antireflective layer thicknesses for modules placed horizontally at the equator and on a roof in the UK. Our results indicate that only modest gains in average short‐circuit current could be obtained by optimizing structures for sunrise to sunset irradiance rather than AM1·5 at normal incidence, and fabrication tolerances and uniformities are likely to be more significant. However, we believe that this overall approach to optimization will be of increasing significance for new, potentially asymmetric, antireflection schemes such as those based on subwavelength texturing or other photonic or plasmonic technologies currently under development especially when considered in combination with modules fixed at locations and directions that result in asymmetric spectral conditions. Copyright © 2009 John Wiley & Sons, Ltd.