Spectral correction of photovoltaic module electrical properties

Abstract

Except for irradiance and temperature, the distribution of solar spectrum also affects the electrical performance of photovoltaic (PV) modules. To explore the effect, this study conducted long-term experimental measurements on the wide range of full solar radiation spectrum with monocrystalline silicon (m-Si) and cadmium telluride (CdTe), and established new spectral correction function (SCF) under horizontal conditions based on the average photon energy (APE). It is verified with a good agreement R² of 0.95, and the maximum RMSE is only 0.017 %. Moreover, the application of the SCFs to building vertical façade has also been well verified, and the accuracy of electrical performance prediction can be improved by 14.51 % (m-Si) and 3.57 % (CdTe). In addition, this study combines the annual horizontal total solar radiation spectrum in Beijing and gives the annual spectral gain and loss (SGL) ratio of two PV panels. The power generation performance of the two PV modules under the actual spectrum will be underestimated for about 53.5 % and 99.7 % of the time in the whole year. This study broadens the dimension of evaluating the electrical performance parameters of PV panels and provides a basis and guidance for the accurate prediction and calculation of photovoltaic power generation.