Evaluation of the Performance of the PVUSA Rating Methodology Applied to Triple Junction PV Technology (Presentation)

The PVUSA (Photovoltaics for Utility Scale Applications) project in the 1990's developed a rating methodology for PV performance evaluation which has become popular, and even incorporated into concentrating PV rating standards. The method is based on collecting solar, meteorological, and system power output data for a period of time, and regressing the system output against a combination of irradiance, wind speed, and ambient temperature. The selected irradiance, wind speed, and temperature rating conditions are I s=1000 Wm-2 , W s=1 ms-1 , and T s=20 degrees C, respectively, for a flat plate collector. Here, we apply the method to a rack-mounted dual-junction PV system, and produce a system rating. We also describe in detail the uncertainties associated with the method, and mathematical issues associated with the technique.