Abstract: Because of changes of weather,it is still a challenge to forecast wind power accurately.In the case of large wind farms connecting to grid,especially in high penetration condition,utilizing prediction information of wind power for scheduling decision directly will bring risks to power system.The energy storage system have the time shift capability with respect to power and energy,which is able to cope with the wind power prediction error effectively and ensure the security of the power system.However,constrained by the current technical and economic level,the cost of energy storage systems is still expensive.Thus,the feasibility of improving the wind power scheduling scale by the energy storage systems should be assessed from the view of the economy.To assess it,an economic assessment model of the energy storage system was built,and different probability interval forecast scenarios were constructed.Research results provide a theoretical reference for application of energy storage systems to improve wind power scheduling scale.