Improved design of a three-dimensional, static concentrator lens using meteorological data

Abstract

A three-dimensional, rectangular concentrator lens (3D lens) has been designed by combining two kinds of two-dimensional compound elliptic lenses and meteorological data. Optical concentration ratios of the 3D lenses designed at various half-acceptance angles are calculated and measured as a function of light incidence angle. Yearly integrated irradiance and yearly averaged module efficiency are simulated using the calculated optical concentration ratios and meteorological data. A performance index - a product of entry aperture and cell occupation ratios - is defined to compare with that of flat-plate modules. Consequently, designed half-acceptance angles are optimized at 40° and 70° in north-south and cast-west directions. The occupation area of solar cells can be reduced to 62% using this lens although module area increases to only 1·16 times that of the flat-plate module. Copyright © 1999 John Wiley & Sons, Ltd.