The present study evaluates the effects of ambient temperature and solar irradiance on the exergy efficiency and power generation of a solar power system with molten salt energy storage. The subsystems included heliostats, a molten salt fluid storage loop, and a steam Rankine cycle. The proposed model sought to minimize CO2 emissions and maximize the net output power. Engineering Equation software (EES) was employed to simulate and analyze the proposed system. The number of heliostats, turbine efficiency, and the input pressure of the steam turbine were found to be the major performance determinants. The Technique for Order of Preference by Similarity to Ideal Solution was adopted to implement multi-criteria decision-making in order to identify the optimal oper-ating parameters. The optimal exergy efficiency and cost rate of the proposed system were found to be 10.76 % and 317.1 $/h, respectively. Moreover, the optimal net output power was 2324 kW. The economic analysis of the system revealed that the heliostats, solar receiver, and steam turbine accounted for the largest, second-largest, and third-largest portions of the exergy destruction. Finally, a comparative case study of Esfahan, Dubai, Bushehr, Bandar Abbas, and Shiraz over a year was conducted to evaluate the effects of ambient temperature, solar irradiance, and wind speed on the system. The results showed that the proposed system performs better in the climate of Shiraz, Esfahan, Bandar Abbas, Bushehr and Dubai respectively. Also, the environmental analysis showed that the proposed system can help to expand 3-4 ha of green space per year.
