Abstract: Disclosed herein are the energy storage system of an Uninterruptible Power Supply (UPS) equipped with the battery and a method of driving the same. The energy storage system includes a commercial power source unit configured to supply a first power source to a load, and the battery configured to supply a second power source to the load. And the system monitors a power failure state in the commercial power source unit, determines a charging state of the battery, and controls the commercial power source unit and the battery in response to output of monitoring or determination, so that the first power source or the second power source is supplied to the load. A power reservation ratio for the use of power can be increased by reducing power used during daytime.

Abstract: Disclosed herein are the energy storage system of an Uninterruptible Power Supply (UPS) equipped with the battery and a method of driving the same. The energy storage system includes a commercial power source unit configured to supply a first power source to a load, and the battery configured to supply a second power source to the load. And the system monitors a power failure state in the commercial power source unit, determines a charging state of the battery, and controls the commercial power source unit and the battery in response to output of monitoring or determination, so that the first power source or the second power source is supplied to the load. A power reservation ratio for the use of power can be increased by reducing power used during daytime.