Impact of tilt angle on the performance of the photovoltaic systems for different row spacing

Abstract

The optimum tilt angle for a photovoltaic (PV) system depends on the row spacing because it affects the amount of shading on the panels. This study modeled PV systems for four different panel row spacings of 2 m, 2.5 m, 3 m, and 4 m in a fixed 3000 m2 area in Konya province, Turkey. For different panel row spacings, the system performances were compared using a constant tilt angle of 35 degrees, expressed as a proper angle for PV installations at the considered location. In addition, the optimum tilt angle is found for four different cases in terms of electricity generation. In systems with 35 degrees tilt angles at electricity were produced annually as 622.77 MWh, 566.49 MWh, 495.36 MWh, and 385.72 MWh, respectively, for panel row spacings of 2 m, 2.5 m, 3 m, and 4 m. In addition, these electricity productions are 6.19%, 4.41%, 2.56%, and 0.92% higher with optimum tilt angles as 1 degrees, 15 degrees, 21 degrees and 27 degrees. Similarly, the Performance Ratio (PR) values obtained with the optimum angles are 20.61%, 8.39%, 4.12%, and 1.44%, higher than the fixed tilt angle cases. According to the economic analysis, systems with a fixed tilt angle for these panel row spacings pay back themselves in 5.13, 4.67, 4.44, and 4.28 years, respectively, while systems at optimum angles pay back themselves in a shorter time by 5.83%, 4.26%, 2.49%, and 0.91%. Furthermore, the highest NPV/INV, IRR, and ROI values were obtained from the system with 3 m panel row spacing with the optimum tilt angle of 21 degrees as 0.915, 20.42%, and 91.57%, respectively, which is techno economically found to be the most feasible case.