Ancillary Services
In one line
Grid stability services — frequency regulation, reserves, voltage support — provided by generators or storage to grid operators.
What it means
Ancillary services are stability and reliability services that grid operators procure to maintain grid quality. These include frequency regulation (primary reserve), spinning and non-spinning reserve (secondary/tertiary reserve), voltage support (reactive power), and black-start. BESS resources earn from ancillary services participation alongside energy market participation.
Related terms
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