Markets & tariffs
Ancillary services
Grid-stability services (frequency control, reserve, voltage support) that the market operator pays for to keep the power system running safely.
Ancillary services are the grid-stability services that the market operator pays for on top of the wholesale energy market. They're what keeps voltage and frequency inside their operational bands even as supply and demand fluctuate.
The main categories are:
- Frequency response (fast, sub-second)
- Regulation (continuous, following an AGC signal)
- Reserves (standing by to activate during a contingency event)
- Voltage support (reactive power)
Batteries are exceptionally well-suited to the fast frequency-response and regulation products, because they can go from zero to nameplate in milliseconds. This is why AS revenue is the single largest grid-side revenue stream for industrial BESS in both the NEM and the Singapore market.
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