Abstract: In order to verify the role of energy storage in peak shaving and economic dispatch of power system under different price policies, the paper models the microgrid with energy storage. Firstly, a typical microgrid is built which contains the wind turbine, photovoltaic cell, combined power and heat system, boiler, fuel cell and energy storage system. Then, given the time-of-use (TOU) price and real-time price (RTP), an economic model is established with consideration of the heat sale profit, maintenance cost and power exchange cost between microgrid and grid, and is optimized with the Hybridize Invasive Weed Bat Algorithm (HIWBA). In addition, in order to verify the effectiveness of the proposed model and the reached conclusions, by taking to the economic dispatch model of microgrid without energy storage under two different price policies as a reference, the paper optimizes the optimal outputs and operation costs of the distributed generator units of a practical microgrid on a typical winter day. The results indicates that the energy storage can help regulate the peak load and reduce the operation costs, and different price policies have different impacts on cost reduction and the effectiveness of energy storage.