Ancillary Service

A set of physics-based support functions that are essential for maintaining the reliable operation of a Power System. Example applications include supporting Supply-Demand Balance, Frequency Regulation, Voltage Management, Black Start Capability and Contingency Capacity Reserve.


The term Essential System Services may be used with reference to or as a synonym of Ancillary Services.

Given the fast-evolving nature of power system transformation, the Future Grid Accelerator (FGA) has the status of a perpetual BETA version. Your suggestions for how each concept and definition may be enhanced are very welcome.

All feedback will be reviewed and considered for inclusion in subsequent updates.

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