An Empirical Study on Energy Performance of 6㎾ Grid-connected Photovoltaic System in Summer Season

Abstract

This paper carried out empirical evaluation on generating characteristics and energy performance of 6 ㎾ grid-connected photovoltaic (PV) system in summer season. The PV system was installed to provide power for lighting and appliance of a nursery accommodating about 100 children and teachers. According to the analysis of the monitoring data, average daily solar irradiance was measured to be 5.44, 2.82 and 4.98 ㎾h/㎡ from June to August, respectively. Meanwhile, average daily power generation of the system was computed to be 29.5, 14.3 and 25.8 ㎾h for each month, and the minimum and maximum values during three months were computed to be 1.2 and 36.4 ㎾h. Therefore, it is considered the power output of the PV system is closely related to the variation in solar radiation. In addition, it was observed that average daily load-sharing ratio of the system was 24, 4 and 25% in each typical day, and average weekly load-sharing ratio was 32, 15 and 23% in each typical week. Therefore, this results show that grid-connected systems is more suitable than stand-alone system in case of last rainy days during the summer season aside from the advantage that are not necessary to install an expensive battery.