Significant research work has highlighted the growing importance of minimizing energy consumption. Air conditioning systems have consumed remarkable amounts of energy over the last decade. This study introduces a retrofit for enhancing the thermal performance of air-conditioning systems characterized by their large energy consumption. The arrangement of a cooling coil, an enthalpy wheel, a solar water heater, a photo-voltaic panel and a thermo-electric cooling panel is studied for the first time to retrofit a conventional 100% outdoor air conditioning system with energy recovery ventilation through the utilization of solar energy for decoupling sensible and latent loads. Modelling and simulation have been performed using the building energy simulation program (EnergyPlus) for a whole year, using the weather conditions of 4 cities across Egypt. The proposed air conditioning system was found to be more power efficient and more economically feasible than the existing conventional system in the case of 3 of the simulated weather conditions. Results show a significant decrease in the annual electric energy consumed by the air-conditioning system, as in the case of Alexandria, the new system achieves a 66.027% saving of the total electric energy consumed annually. In the case of Cairo, the annual saving is estimated to be 60.104% and 51.392% in the case of Hurghada. For the city of Aswan, the new system consumed 41.163% more electric energy than the old system throughout the year.