Performance and reliability evaluation of concentrated photovoltaic (CPV) power plants

Performance and reliability evaluation and analysis of three concentrating photovoltaic (CPV) systems or power plants are presented at the string levels excluding the thermal and module level analyses. These plants are located in Arizona and were commissioned in mid-2012 (about 2 years old). The strings in all three power plants are operating between 79% and 0% of the rated capacity, and the average string operating capacity is only 34%. This paper indicates that the primary reason for power drop or complete loss of power in these CPV plants is due to misalignments in the tracking system. It was found that due to thermal stressing, wind loading, and tracker drift, tracking misalignment challenging the tracker controller was the most severe issue for performance drop or complete loss. This paper indicates that the reliability issues that need to be addressed by the CPV industry are not just on the cell level, but also on the precision of the systems' tracking.