Measurement and characterization of concentrator solar cells

Concentrator solar cells are winning favor for power systems because of the high cost of solar cells and improvements in sun-tracking technology. Accurately measuring the performance and efficiency of cells under concentration is difficult. Determining the light concentration on solar cells traditionally has been done by using a ratio of the measured short circuit current to that at one sun. This works well with low to moderate (<20 suns) concentration levels on well-behaved cells but does not apply when cells exhibit superlinear or sublinear behavior. This paper is being written to provide additional geometrical aids using view factors to determine the concentration level and linearity of the solar cell with both mathematical and experimental results.