The modern power system network comprises distributed generations of renewable sources. The intermittent nature of renewable sources may not always support the peak demand of the electricity network; therefore the integration of storage batteries can support the peak demand for retaining power system stability. The battery of fast charging loads like electric vehicles (EV), electric ferries (EF) and others can also be used for peak shaving of the power system. The storage elements can provide FCAS (frequency control ancillary service) to the power system for restoring the system's stability. To justify the peak shaving option of storage battery, a 9-bus system electrical network is created by OpenDSS which analyzes the charging and discharging characteristics of the battery. The storage controller controls the storage batteries in two modes, one follow-time (discharging and charging) mode and another load-shape (charging and discharging) mode. The storage controller controls the sequence of operation of the batteries to meet the load demand of the electrical network. The proposed approach can be used for a large electrical network to manage the peak demand to retain power system stability.