Impact of aerosols on photovoltaic energy production using a spectrally resolved model chain: Case study of southern West Africa

Abstract

The potential for photovoltaic (PV) power generation in the sun rich countries of West Africa is vast, and could play a vital role in increasing the region's electricity supply. In this context it is important to study the effect of atmospheric aerosols on solar irradiance and PV power. Based on an analysis of the aerosol optical properties for Cotonou, Benin from the DACCIWA measurement campaign, we investigate the impact of aerosols on PV power for polycrystalline silicon and amorphous silicon technology using a spectrally resolved model chain. The model considers both spectral effects on global irradiance due to different aerosol properties as well as the spectral response of different PV technologies. First, we study the contribution of various aerosol types (mineral dust, biomass burning and anthropogenic pollution) that were classified based on the DACCIWA data analysis. Subsequently, we present differences between these imaginary aerosol scenarios and the real case of a biomass burning outbreak on July 13, 2016 in Benin.The results show that aerosol emissions due to the biomass outbreak on the day of the case study in Cotonou lead to solar flux losses of up to 55%, which correspond to a reduction in photovoltaic power of up to 81% for the polycrystalline cell and 78% for the amorphous cell. The relative impact of aerosols differs depending on aerosol type and concentration, and is larger for high solar zenith angles than at noon. For the situation studied in Cotonou, Benin, we are able to show that the inclusion of spectral aspects makes a significant difference when calculating the PV power. Comparing the effects of aerosols on the photovoltaic power between the two technologies, we find that during the morning and evening hours, when there is more diffuse irradiance, the amorphous cell suffers a greater reduction in power (36%) than the polycrystalline cell (27%). Conversely, in the middle of the day, we observe a greater PV power reduction of 12% for the polycrystalline cell compared to that for the amorphous cell (8%).