A method for an efficient operation of a battery energy storage system (BESS) associated with frequency control problem is presented in this paper. A control system model is proposed to simulate the operation of BESS, and a controller is designed. The strategy is based on model predictive control to ensure the optimal operation of BESS in the presence of system constraints. A frequency prediction model based on Grey theory is also designed to optimize the performance of the predictive controller. The method is tested using real measurements from a power grid. The simulation results depict the effectiveness of the proposed approach. (C) 2012 Elsevier Ltd. All rights reserved.