Optimization of 1-Axis Tracking with N-S Rotating-Axis Orientation

This study shows that 1-axis E- W tracking installations with the axis of rotation inclined N -S (INS) towards the equator, can harvest significantly more solar energy than the same system with its rotating axis placed horizontally (HNS), and these systems can have a solar irradiation harvesting performance approaching that of 2-axes tracking systems at a lower cost than the later. The system performance is estimated using the Perez and the HDKR models for installations in locations of high solar irradiation. It is shown that a 15-degree INS tracker would increase the capacity factor of HNS from 29% to 36% in Phoenix and from 35% to 41 % in Northern Chile (based on the percentage increase compared to latitude-tilt fixed system). The applicability of INS to long 1-axis tracker designs and the associated incremental cost are being investigated to assess the trade-off between increased performance and increased balance of system and installation costs.