Performance analysis for the long-term field verifications of grid-connected photovoltaic system: Case study in Taiwan

Abstract

In recently years, global warming and climate change have gradually emerged. Photovoltaic (PV) energy has attracted intensive research effort, due to its unique properties and versatile applications. The power generated by the PV systems can be directly supplied to buildings or electrical grids to reduce high costs associated with using energy such as electricity and fossil fuels. However, due to the low energy-conversion efficiency of the PV systems, it is necessary to improve the performance of the PV systems by tackling energy loss issues. In order to achieve the maximum power output in real time, the Maximum Power Point Tracking (MPPT) control technique is essential to PV-assisted generation systems. In this study, we have evaluated the performance of a PV system on the roof of the bulling at National Taiwan University. The tracking of the maximum power output of the PV system can be achieved in real time, while the power tracking with a Perturbation and Observation (P&O) method remains unchanged. Based on experimental results obtained from an outdoor environment over one year, the performances of PV modules under outdoor operations are deeply affected by their location and environmental conditions. The relationship between the performances of the PV system and the irradiation conditions for the multi-crystalline silicon PV modules utilized in the proposed system was examined in detail.