The germanium primarily based perovskite FAGeI3 provides itself as a value-effective and especially efficient absorber cloth for photovoltaic programs, providing enormous capability to reap excessive power conversion efficiency (PCE). This observation is crucial for comparing the impact of parameters together with temperature, defect density (Nt), thickness, band gap (Eg), and doping attention (NA) on the overall behavior of photovoltaic gadgets. It introduces a unique inverted perovskite solar cell (Glass/Spiro-OMeTAD/FAGeI3/IDL/ZnO/C60) with the use of a simulation tool. FAGeI3 distinguishes itself as a promising fabric because of its thin band gap and broader spectrum as compared to its lead primarily based counterparts. Through optimized parameters, FAGeI₃-based PSCs demonstrated significantly improved performance, achieving an excellent power conversion efficiency (PCE) of 16.74%, an open-circuit voltage (Voc) of 4.12 V, a short-circuit current density (Jsc) of 22.66 mA/cm2, and a fill factor (FF) of 17.94%. This model gives researchers with a treasured tool for characterizing fundamental sun mobile parameters, thereby facilitating the development of high-overall performance photovoltaic gadgets.