The Effect of Collector Shading and Masking on Optimized PV Field Designs

Abstract

Photovoltaic (PV) solar fields are deployed with multiple rows. The second and subsequent rows are subject to shading and masking by the rows in front. The direct beam incident radiation on the second row is affected by shading and the diffuse incident radiation is affected by masking, expressed by sky view factor. Hence, all rows, besides the first one, receive lower incident radiation. The design of PV fields must take into account the decrease in the incident radiation caused by these two effects. The paper investigates by simulation the annual incident diffuse, direct beam and global radiation on the first and on the second row for optimized PV fields at two sites: Tel Aviv, Israel, with low diffuse component, and Lindenberg–Germany monitoring station, with a high diffuse component. The study emphasizes the importance of the diffuse incident radiation on the energy loss of the PV field. The percentage annual global energy loss due to shading and masking on the second row amounts to 1.49% in Tel Aviv and 0.46% in Lindenberg. Isotropic and anisotropic diffuse models were considered. The calculated diffuse incident energy for the isotropic model is lower than the values for anisotropic model by about 8% in Tel Aviv and 3.75% in Lindenberg.

Shading and Masking of PV Collectors on Horizontal and Sloped Planes Facing South and North—A Comparative Study

“…The study presented in [16] shows that increasing the row distance has a greater effect on the masking losses than on the shading losses. Reference [16] refers to horizontal and sloped planes facing south; however, with the extension of the present study for north-facing sloped planes, it is plausible to state that the sensitivity of shading losses to row distance is less pronounced than that of masking losses since the row distance is determined by the same criteria for all three cases of land. Percentage of shading losses between the first and second collector row; H = 2.12 m, L = 40 m, φ = 32…”

“…The work in [15] analyses the sky view factor for isotropic and anisotropic diffuse and albedo radiation. The effect of shading and masking on optimized PV system deployments is dealt with in [16] for horizontal and sloped fields. Numerous articles, including [17,18], to mention a few, investigate the effect of non-uniform solar radiation on the PV module's electrical output power resulting from shading and masking on the PV modules.…”