On the PV Tracker Performance: Tracking the Sun Versus Tracking the Best Orientation

Abstract

This article models the performance of photovoltaic tracking algorithms worldwide, based on the overall insolation collection, by comparing two tracking algorithms, namely tracking the sun (TS) and tracking the best orientation (TBO). In general, the latter is expected to receive higher irradiance with the drawback of requiring a higher installation and maintenance cost (due to the extra sensors). The aim of this research is then to quantify how big the difference is on irradiance collection from these two trackers worldwide by analyzing the data from 61 ground weather stations. In addition, three different tracking mounting structures are considered in this work: first, horizontal single axis tracker (HSAT); second, tilted single axis tracker (TSAT); and third, dual axis tracker (2T). Furthermore, the irradiance collection from front and rear sides are estimated for installations of monofacial and bifacial modules. The simulations reveal that, although the TBO results are higher than the TS ones, there is not a big difference on their insolation collection for latitude locations below 60° (<1.8%). Nevertheless, for higher latitude locations, TBO tracking systems can achieve a considerably higher performance reaching values of up to 3.3%, 7.1%, and 2.9% for HSAT, TSAT, and 2T systems, respectively. It was also observed that for bifacial and 2T systems in particular, high albedo values would produce a considerable enhancement on the TBO performance with respect to TS.