A profit-based unit commitment model for a concentrated solar power (CSP) plant with a thermal energy storage system (TES) incorporating the component operating characteristics is proposed. The model considers three startup types and one shutdown type for the receiver and the power block and corresponding energy constraints. The model maximizes the operational profit of the plant by optimizing the commitment timing, thermal energy flows among the receivers, the thermal energy storage and the power block, and generation levels of the power block. Comparing with a traditional unit commitment model of system planning, the model includes more detailed operating constraints of thermal energy and power constraints in startup and shutdown processes and the solar irradiation conditions, in addition to arbitrage opportunity arisen from price variation. The model is tested in a one-week operating horizon at a time resolution of fifteen minutes. The results have shown that the optimized commitment decisions and operating levels are well matched with the resource availability and price patterns and imply that the model would be useful to the plant operator for operation planning.