This paper proposes a 10MW 3.3MJ Energy Storage System consisting of 4000 Flywheels controlled by ICT network. The flywheel has a lot of advantages such as an environmental friendly, long life time, easy manufacturing and etc. The proposed system consists of the many small capacity flywheels and the high speed communication network. Therefore proposed system has a high flexibility from small capacity to large capacity. The 90% efficiency of charge and discharge for the flywheels are confirmed by experimental results. Moreover 1kWh energy capacity and 200W loss of rated flywheel rotation speed are obtained.