Carrisa Plains PV power plant performance

The authors summarize the performance of the world´s largest PV (photovoltaic) power plant (the one at Carrisa Plains, California) for 1984-1989. Although the plant has high availability, energy production efficiency has declined at the rate of 8-12% per year since 1986. Based on the data, it is difficult to provide a thorough explanation for the steady decline in Carrisa Plains PV performance. The core problem has largely been attributed to the thermal oxidation of ethylene vinyl acetate PV cell encapsulant caused by elevated temperatures of the mirrored segments. The PV modules, originally dark blue in color, are now brown. A number of possibilities exist which may contribute to the plant´s decline in power output, such as mismatching, leakage currents, inappropriate inverter operating point, and changes in maintenance. Performance results of the mirrored and nonmirrored segments are presented These results indicate that the nonmirrored segment is performing well with minimal efficiency degradation and low operation and maintenance costs