Visual degradation and performance evaluation of utility scale solar photovoltaic power plant in hot and dry climate in western India

The current work presents techno-economic study, degradation analysis and performance assessment for seven consecutive years from 2013 to 2019 of 5 MW grid connected crystalline silicon solar photovoltaic (PV) power plant with monthly variation in tilt adjustment done manually in hot and dry climate of Gujarat, India. Hot spots, junction box melting, encapsulant discoloration, snail trails, corrosion of metallization and interconnects due to moisture ingression were among the main degradation modes and faults observed in large number of fielded PV modules with operational time of eight years. Various performance indices such as monthly mean reference yield, final yield, performance ratio (PR), capacity utilization factor (CUF) and PV system efficiency are calculated from recorded energy generation and environmental data and analyzed. Economic and Environmental analysis of the inspected plant in terms of payback period, levelized cost of electricity (LCOE) and mitigated CO2 emission is also presented. PVSyst and Helioscope are the software simulation tools used for PV plant modeling, losses prediction and verification with the calculated performance indices. Possible causes, impact and corrective measures for various degradation mechanisms and failures observed in fielded PV modules are presented. Based on the findings by number of researchers globally and conducted performance and degradation analysis of the inspected plant, specific conclusion and key recommendations are enlisted.