This work deploys a configured hypothetical 6-kWp capacity PV system, with mounted rooftop panels, to examine the performance of a PV system, corresponding to different (a) PV cell technologies; (b) ambient temperatures. The first (crystalline silicon (c-Si)) and second (copper indium gallium selenide (CIGS)) generations of PV cells have been chosen for this study. A range of ambient temperatures, -10 degrees C to 50 degrees C, at an interval of 5 degrees C, will be used to investigate the influence of temperature on PV system performance, using the chosen PV cells. A PV design and simulation software, PVsyst, was deployed based on optimisation considerations. It was observed from the report that: the CIGS PV cell produced the highest energy at standard tests and conditions (STC) and elevated temperature; the Si mono and polycrystalline yielded the same amount of energy; the CIGS and Si monocrystalline cells PV have the highest and lowest PR, respectively.(c) 2022 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Ain Shams University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/ by-nc-nd/4.0/).