A novel backtracking approach for two-axis solar PV tracking plants

Solar tracking is a technique required to increase energy production in multiple photovoltaic (PV) facilities. In these plants, during low-elevation solar angle hours, shadows appear between the collectors causing a dramatic decrease in production. This paper presents a novel optimal tracking strategy to prevent the creation of these shadows. The presented method determines whether or not there is shading between collectors. Thus, when the collectors are not shaded, a tracking trajectory for maximum irradiance on the collectors is suggested. However, when the collectors are shaded, backtracking is proposed. Therefore, energy production in plants with this novel tracking method can be 1.31% higher than that in PV installations with astronomical tracking. Moreover, this method allows the study of PV facilities for which there have been no published approaches, such as plants with non-rectangular collectors or those located on topographically heterogeneous surfaces. •A novel approach for optimal tracking in PV collectors preventing shadows is proposed.•The method presented shows how backtracking improve other usual solutions.•Non-rectangular collectors or non-flat topography can be analysed with this approach.•Increases of 5% in energy production in two-axis tracking PV plants can be achieved.