Unit commitment is one of the most critical problems in power system operation. The objective of the unit commitment problem is to determine the start-up and shut-down schedule of generating units for a given planning horizon with the aim of maximizing social welfare while satisfying the load demand and meeting the technical and security constraints. This paper proposes a model based on Mixed-Integer Linear Programming (MILP) as a way of dealing with the unit commitment problem of thermal-wind-BESS integrated systems considering network power loss. This MILP based-formulation is developed from the Mixed-Integer Nonlinear Programming (MINLP) model by linearizing the power loss. The proposed model is validated using the power transmission system of the IEEE RTS 24-bus. The calculation results reveal that the power loss makes a considerable impact on the commitment of production units, the actual power output of the committed generating units and scheduled storage power.