Investigation of Efficiency for PID-Affected Solar Module at Nonstandard Test Conditions

Potential-induced degradation (PID) causes a sharp decrease in the efficiency and shunt resistance of the solar module. In this paper, PID-affected modules were studied detailedly under non-standard light conditions for the first time. The trend of efficiency degradation was obtained by measuring irradiance-efficiency ƞ and the ΔI-Δƞ. The result shows that the efficiency (I-ƞ) of PID-affected module reduced by 1.28% which is rather higher than the 0.2% of PID-free module when the light intensity changes from 400 W/m2 to 200 W/m2. This means that efficiency of PID-affected module decreases more seriously in low light conditions.