Performance analysis and energy metrics of grid-connected photovoltaic systems

Abstract

The performance of two co-located grid-connected photovoltaic (PV) systems comprising polycrystalline silicon (p-Si) and copper indium selenium (CIS) arrays are analyzed in this work. The measured and simulated performances are compared with an objective to study the suitability of the technology in the real hot and humid climatic conditions of Tamil Nadu, Southern India. The parameters used for the performance evaluation are array yield, final yield, PV efficiency, performance ratio and capacity utilization factor. The year-round performances of both the photovoltaic (PV) systems are predicted by PVsyst software using measured weather data at the site and compared with that of the actual measured results. The normalized measured annual energy delivered to the grid is 1536.9 kWh and 1698.4 kWh for p-Si and CIS PV systems respectively. The yearly average performance ratio is 78.48% for p-Si and 86.73% for CIS while the capacity utilization factor varies from 17.99% (for p-Si) to 19.57% (for CIS) respectively. Also, high capture losses are observed in the p-Si PV plant than that in the CIS PV plant. The performance indices of the PV systems are compared with that of the similar capacity PV systems situated at other locations. Further, embodied energy, energy payback time (EPBT), energy production factor (EPF), and life cycle conversion efficiency (LCCE) of the PV systems have also been estimated. The energy yield of CIS array is found to be 7.61% more in comparison to p-Si array round the year favoring its suitability for potentially, sites with a similar climate.