Ancillary Services

Ancillary services are those services used by AEMO to manage the power system safely, securely and reliably. These services maintain key technical characteristics of the system, including standards for frequency, voltage, network loading and system restart processes.

AEMO operates 8 separate markets for the delivery of frequency control ancillary services (FCAS) and purchases network control ancillary services (NCAS) and system restart ancillary services (SRAS) under agreements with service providers.

Following the AEMC’s determination of the Network Support and Control Ancillary Services (NSCAS) Rule 2011 No.2, TNSPs have been given primary responsibility for meeting NSCAS demand while AEMO’s role from 5 April 2012 will be to act as NSCAS procurer of last resort.

FCAS providers submit bids in a similar way to generators bidding into the energy market. Payments for ancillary services include payments for availability and for the delivery of the services.