Performance Comparison of Terrain-Informed Backtracking Methods for Single-Axis PV Trackers Considering Mechanical Architecture

With flat land for photovoltaic (PV) installations becoming scarce, systems are increasingly deployed on undulating terrain where row-to-row shading can reduce energy output during low sun elevation angles. This study compares several terrain-informed backtracking algorithms aimed at reducing shading losses in single-axis tracking PV systems. The analysis focuses on two operational PV sites: one with significant terrain undulation in Spain, and another with moderate variation in Northern California. Using a high-fidelity simulation tool, we evaluate ground coverage ratio (GCR) tuning method and show that while it reduces shading, it can cause energy losses due to leaving unutilized light on the ground on undulating terrains. We also assess five slope-aware backtracking variants at different levels of granularity—from block-level to tracker-level control—and analyze linked-row and independent tracker configurations. Results show minimal gains for block-level slope-aware backtracking, with improved performance at finer granularities. The tracker-level slope-aware backtracking variant, designed for independent tracker architectures, achieves the highest energy gain among all slope-aware backtracking variants, outperforming the linked-row configurations. Nextracker’s TrueCapture Split-Boost algorithm, combined with independent tracker architecture, achieves the greatest energy gains—1.59% for the Spain and 1.94% for the California site—by precisely accounting for terrain variations and allowing controlled partial shading to optimize energy yield. This study highlights the importance of accurate terrain-aware tracking and flexible mechanical design to maximize energy production on complex terrains.