Single Axis Tracker Performance Modeling on Sloped Terrain
Benjamin C. Pierce, Joshua S. Stein, Daniel Riley · 2023
As solar photovoltaics (PV) become more widespread, installations have become more nuanced to model due to complex terrain, such as hills or mountains. Single axis trackers (SATs) provide the best economic performance on the market, and as such, modeling their performance is quite relavent. However, SATs are more difficult to model then traditional fixed-tilt systems due to a vareity of factors. This work focuses on modeling slope-aware backtracking, a modification to the current backtracking algorithm that takes terrain slope into account to avoid row-on-row shading. We present a methodology that uses digital elevation models (DEMs) to automatically calculate the terrain slope and its orientation, which can then be used to calculate tracker positions. Furthermore, we present a comparison of modeled tracker performance with and without awareness of the terrain, and show a 1% performance difference between the two. The magnitude of this effect is then useful to know when evaluating the performance of installed and proposed SAT installations.