Since the 1990s, solar energy has been hybridized with fossil power plants to improve reliability and efficiency. This study proposed an economical model for the solar-coal hybrid system. A conventional 200 MW coal-fired power plant was hybridized with solar heat at approximately 300 degrees C and compared with a typical solar-only thermal power plant. The annual thermal performances of the proposed system were estimated and they were economically assessed using the economic model. The appropriate replacement configurations for the system can be determined for lower solar electricity cost. Therefore, this system may utilize solar energy on the utility scale cost-effectively.