Global Comparison of the Impact of Temperature and Precipitable Water on CdTe and Silicon Solar Cells

Solar cells made from different materials are differently affected by the climatic conditions in which they operate. Response to precipitable water and temperature are fundamentally different for base materials with different bandgaps. In this contribution we investigate theoretically how precipitable water and temperature affect the harvesting efficiency of Silicon (Si) and Cadmium Telluride (CdTe) solar cells. Harvesting efficiency calculations capture the differences in local solar cell operation clearly and provide insights beyond those provided by the standard testing condition (STC) efficiency. We use readily-available satellite data to calculate worldwide harvesting efficiencies for a CdTe solar cell with an STC module efficiency of 15.7% and a Si PERC solar cell with an STC efficiency of 20.7%. We find that the different operating conditions found on Earth account for variations of up to ± 23 kWh/m 2 annually in power generation difference when comparing those two solar cell technologies.