Sun Tracker Performance Analysis for Different Solar Module Technologies in an Alpine Environment

The objective of this study is to compare the performance of different solar module technologies mounted on a fixed-tilt rack (30 deg) as well as on a single and a dual axis tracker. The data of this study were taken from a 724 kWp multitechnology test field at the Airport of Bolzano in the Italian Alps (position ca.46.46N, 11.33 E), which the European Academy of Bolzano is monitoring. The technologies tested were polycrystalline silicon (p-Si) and heterojunction with an intrinsic thin-layer (HIT). We compared the performance of each system in terms of energy output, as well as the performance ratio of both technologies on the different mounting systems. A detailed shading analysis was performed and losses due to the mountainous environment were determined. Further we analyzed miss-tracking, namely, due to shading of the position sensor on the single axis tracker and further, due to high wind speeds, at which the dual axis tracker moves to a safety position. Identifying these problems helps to maximize the tracker performance and hence the energy harvest. A cost benefit analysis was then performed based on the cost of the trackers, energy price, and by comparing the results with fixed installations.