In this study, the Al-Qatrana powerplant of Jordan, comprising a combined cycle, was integrated with a proposed solar power and thermal energy storage system. This study aims to conduct a comprehensive transient analysis and introduce an operating methodology for the smooth transition between the different system’s operating modes. First, a comparison between the conventional powerplant and the proposed system was presented. Results showed that the integration could lead to a 41 MW improvement in output power, a 10.2 % increase in efficiency, and a 9.2 % relative decrease in SFC at design conditions. After that, shaving the summer peak load of the year 2040 using the proposed system was investigated, following the Jordanian National Electric Power Company vision, where the existing plant will be incapable of coping with the load demand. Hence, the solar and storage systems were utilized to boost the plant’s power. The system was able to meet the 2040 summer peak load and overcome the challenges that stem from the dynamic nature of the load demand and the solar radiation availability. Finally, a feasibility analysis was conducted, the results showed that the return of investment period is 8.58 years, which is encouraging.