Optimization of Device Design for Thin-Film Stacked Tandem Solar Modules in Terms of Outdoor Performance

摘要

The device current-voltage (Ⅰ-Ⅴ) characteristics of thin film silicon stacked tandem solar modules (HYBRID modules) consisting of a hydrogenated amorphous silicon (a-Si:H) cell and a thin-film microcrystalline silicon solar cell (μc-Si) have been investigated under various spectral irradiance distributions. The spectrometric characterization had revealed that the performance of the HYBRID module exposed to sunlight tended to be limited by the top a-Si:H cell due to the photodegradation of the top cell, and the bottom μc-Si cell of the modules was stable as before exposure. The HYBRID module limited by the top cell exhibited a more efficient performance than the bottom-limited module in natural sunlight at noon. This behavior is well explained by the contour analysis of the performance as a function of spectral irradiance ratio and module temperature.