Performance comparison of CdTe thin film modules with c‐Si modules under low irradiance

The efficiency of solar panels declines from its rated (standard testing conditions) value under low irradiance which typically occurs in the mornings, evenings and on cloudy days. In this work, the authors evaluate cadmium telluride (CdTe) thin film panels due to their increasing market share and assess their low irradiance performance in comparison with conventional crystalline‐Silicon (c‐Si) panels. The performance of both material systems is analysed for a 4‐year period to evaluate their performance in terms of their relative change in efficiency and energy yield. Further analysis on a high‐resolution 8‐day measured data for winters and summers shows that CdTe panels provide ∼1.09% higher specific energy yield compared to c‐Si panels. This primarily occurs due to higher CdTe bandgap and better spectral response at lower insolation levels resulting in an enhanced relative efficiency with respect to c‐Si panels.