Electrical Power Improvement of Grid-tied Photovoltaic Solar System

Abstract

Abstract: The method that is used to improve performance and electrical power is to use optical reflectors. Optical reflectors improve performance and electrical power, because they increase solar irradiation. CIGS is an acronym for Copper Indium Gallium Selenide. CIGS PV solar module is a second-generation thin-film technology. The system with which optical reflectors are attached is 5kWp. CIGS PV solar system is situated at Al-Mansour factory, Baghdad-Iraq (longitude 44.4°E, latitude 33.3°N and 41m above the sea level). This study improves electrical power, current, performance ratio and array efficiency. All these improvements are done by increasing solar radiance via utilizing optical reflectors (fabricated from aluminum metal). The current system is divided into two parts: improved (PV modules with optical reflectors) and reference part (PV modules without optical reflectors). At 12:00 PM, the largest values of the solar irradiance, electrical power and current for improved and reference PV modules are 1346.1 W/m2 and 981.5 W/m2, 2.308 kW and 1.712 kW,6.01 A and 4.44 A, respectively. At 7.30 AM and 5:00 PM, the largest values of performance ratio and array efficiency of 98% and 14.8%, respectively, are recorded, while the minimum values are at 12:00 pm of 91% and 92.5% and 13.8% and 14.1%, respectively. The largest values of the improved and reference PV module temperatures are 56°C and 50°C, respectively, at the ambient temperature of 21°C. At 7:30 AM, the lowest values of the electrical power, current, solar irradiance and temperatures for the improved and reference PV modules are recorded to be 0.276 kW and 0.267 kW, 0.68 A and 0.65 A, 142.67 W/m2 and 138.44 W/m2, 33°C and 34°C, respectively, at an ambient temperature of 16°C. The maximum increment percentages (gains) for power, current, solar irradiance and module temperatures resulting from using optical reflectors are 34.4%, 35.3%, 37.1% and 6°C, respectively. The current work was achieved under clear sky conditions. The mean increment throughout a day is 24.4%, which is a very good indication of economic feasibility. Keywords: PV solar system, Efficiency, Optical reflector, Grid-connected, CIGS.