The main goal of this paper is to design an efficient renewable energy system that meets the required electricity demands. Consequently, it is essential to find the most cost-effective hybrid system that can reduce energy costs and provide access to the required electricity generation. An international school in New Administrative Capital in New Cairo, Egypt was chosen as a study area for the proposed system. Solar, wind, and biomass resources are abundant at the chosen location throughout the year. Using the HOMER (hybrid optimization model for electric renewables) software, eight distinct models of renewable energy hybrid systems were designed, simulated, and optimized to meet the required load in this study. For wind and solar resources, the National Aeronautics and Space Administration (NASA) provided the input data; for biomass resources, real-time field data were used for the selected study site. In this study, lithium-ion and lead acid batteries were used to choose the most cost-effective option. The hybrid power system's PV, wind, and biomass generators were utilized to meet the load demand. The overabundance of energy requests was utilized to charge the battery banks as required when accessible to cover the load requirements during times of low energy production.