Solar energy is a prompt creating source of energy worldwide. Airports are typically large and shade-free structures, which offer the idealistic platform for installing large surfaces of photovoltaic panels generating more than 20 GW/yr. Optimization is a key factor to promote the power conversion efficiency. Solar-radiation amount depends on an essential factor, which is the orientation of the photovoltaic modules. The azimuth and tilt angles for the photovoltaic panels affect the receiving of the solar radiation, accordingly have a major influence on the photovoltaic system performance. PVsyst software is an important simulation for the design of the photovoltaic system. This study provides a proposal for installing a photovoltaic plant in Cairo International Airport. Moreover, the study gives several orientation cases to get the optimum yearly tilt and azimuth angles to maximize the annual energy yield. The study also improves the energy generation by carrying out optimization to obtain the dual-seasonal optimal tilt angles for summer and winter. The energy simulation and the orientation-optimization were done by the PVsyst software. The optimization results indicated that the optimal azimuth angle is 0°, the optimal yearly tilt angle is 30°, and the generated energy is around 35 GWh/yr. The optimal dual-seasonal tilt angles are 10° in summer and 50° in winter that maximized the generated energy to be about 36.5 GWh/yr. This optimization study contributes effectively to increase the energy production by using an optimal photovoltaic panel-orientation, as well as being able to save about 50% of Cairo-International-Airport Terminal-Building 3 yearly electrical consumption.