This chapter is devoted to energy storage in power systems. There are three possibilities for the use of storage in the power system: compulsory regime; optimal regime; and reserve regime. A compulsory regime arises when the planned load curve coincides with the rated load curve; there is a necessity for the energy storage unit to ensure power balance in the system. It may arise in two different ways: (i) During the trough period, when load demand is less than the technical minimum of the total installed generation equipment. The energy storage is charged so that stored energy can then be used during peak demand, (ii) During the peak period, when load demand exceeds the total generation. In this case, the energy stored has to be discharged at its rated power capacity. The necessary energy was accumulated by the ES during the previous load trough. Unused or spare energy storage capacity may also be used as spinning reserve. Use of the reserve regime provides fuel saving whenever there is a need for spinning reserve. Table 16.1 shows how constant loading decreases the fuel consumption necessary to generate a given amount of energy.

Inspec keywords: energy storage; power systems

Other keywords: spare energy storage capacity; fuel saving; compulsory regime; power capacity; optimal regime; spinning reserve; energy storage; power system; load curve; reserve regime; fuel consumption

Subjects: Power systems