A Study of Performance Characterization with Rear Light Source in Conventional Bifacial Solar Cells

Abstract

We compared bifacial solar cell measurement results between bifacial irradiation and theoretically calculated values. Conventional solar simulator was modified to measure bifacial solar cell with rear side LED light source. Bifacial solar cells which were used to measure were from 2 companies mass production. In this paper, each side of bifacial cells was measured under standard test condition as first time action. The other cell side which is opposite side of light irradiation was covered with nonreflecting velvet plate to prevent light reentry from cell penetration or unintended directions to cell. So, we expected that measurement data could be exacted by excluding unnecessary factors. These measurement results that each side of cell, front and rear side, are used to calculate expected bifacial cell characteristics. Secondly, we measured bifacial solar cells characteristics with bifacial irradiation with newly installed bifacial solar simulator. The measurement result with bifacial irradiation is compared with theoretical bifacial cell values which were calculated with bifacial cell formula. As a result, we can verify difference values of efficiency and power were within ±3%. So, it can be possible that conventional solar simulator could be used to measure bifacial solar cell if there are expected diode ideality factor (n) and front/rear side of cell measurement result under the standard test condition (STC).