Spatial Mapping of Front and Rear Irradiation of a Horizontal Single Axis Tracking PV System With Multiple Row-to-Row Pitches

This study presents a spatial mapping of front and rear irradiation of a two-in-portrait (2P) Horizontal Single Axis Tracking System (HSAT) PV system with multiple tracker pitches installed in Qatar’s desert environment. Based on one year of field measurements, the average seasonal front daily plane-of-array (POA) irradiation ranged between 5.3-5.9 kWh/m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /day during winter and 8.75-8.92 kWh/m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>/day in summer months. Over one year, HSAT systems received 15.0% higher front POA irradiation compared to South-facing 22° fixed-tilt surfaces. Between tracker pitches of 8.7 to 12.0m, rear POA Irradiation was 5.5-6.5% higher per meter. Wider pitches exhibited greater rear-side irradiation uniformity, with edge-to-center irradiation differences below 8%, while the narrowest pitch had a rear-side irradiation edge-to-center non-uniformity exceeding 11%. The ratios of rear-to-front irradiation increased with tracker pitch, measuring 10.3%, 12.0% and 12.8% at tracker pitches of 8.7m,10.7m and 12.7m respectively.