The manuscript describes the deployment of a centralized model predictive control (MPC) strategy to effectively manage voltage and frequency regulation within a multi-source power system driven by renewable energy sources. Herein, a power network containing generation from thermal, diesel, and solar thermal power plant (STPP) units has been considered. Herein, an enhanced whale optimization algorithm (EWOA) has been applied to fine-tune the MPC parameters. The transient response of the controlled model has been equated with other methods reported in the related works. Further, the superiority of the EWOA-MPC method has been proved under the stochastic renewable generation scenario. The simulation-based results have showcased the excellent transient and robust nature of the proposed methodology.