Performance assessment of an on-grid 178.08kW Photovoltaic system Islamabad, Pakistan

It is anticipated that renewable energy will meet a considerable fraction of future energy demands of Pakistan. Since solar energy is abundant in most parts of the country, on grid solar PV systems are becoming increasingly important. Electric energy provided by the solar power plant to the grid depends upon seasonal variation of the solar resource, losses by temperature changes, system losses and losses due to grid conditions. This paper presents the monitoring result of a 178.08 kW grid connected photovoltaic system installed in Pakistan engineering commission, Islamabad (Longitude 73.0667° & Latitude E 33.7167° N). System was monitored between Jan 2013 to Dec 2013. Daily solar irradiation, ambient temperature, wind speed, daily power generation were measured and analyzed during this monitoring period. Performance ratio manually calculated from the recorded data is 0.63. Furthermore, the PV performance was studied by performance ratio variation with solar inclined irradiation. Average monthly performance ratio was found to be decreasing with increasing ambient temperature and solar inclined irradiation. A decreasing trend in AC power was seen with rise in temperature and conversion losses.