The Use of Convex Lens as Primary Concentrator for Multi-Junction Solar Cells

Juan Paolo Lorenzo Gerardo Barrios1, John Raffy Cortez1, Gene Michael Herman1, Aris Larroder1, Bernice Mae Yu Jeco2, Kentaroh Watanabe2 and Yoshitaka Okada2
1Philippine Science High School Western Visayas Campus – Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology, Philippines
2Research Center for Advanced Science and Technology, The University of Tokyo – 4-6-1 Komaba, Meguru-ku, Tokyo 153-8904, Japan


Abstract
A concentrator lens system was designed for a multi-junction solar cell, CDO-100-C3MJ, with an added feature-a convex lens was added above the Fresnel lens, in order to improve the efficiency of the setup. The convex lens setup was tested with the Fresnel lens setup over a three-day photoperiod by measuring the voltage, current, irradiance, and temperature at every hour. The results showed that the convex lens setup produced 1.04 percent more power, but only at around midday. The power difference caused by the convex lens was determined by the Wilcoxon Signed Test to be significant for the photoperiod, as it focuses a greater amount of sunlight on the solar cell over the course of the day.