Our approval role
The Improving Security Frameworks for the Energy Transition rule change (the ISF Rule), published on 28 May 2024, changed the way Transmission Network Service Providers (TNSPs) recover the costs of System Security Network Service (SSNS) payments made for system security services.
System security services include system strength, inertia, and network support and control ancillary services, typically provided by a synchronous generator or battery, to ensure our power system is secure as we transition to more renewable generation.
The ISF rule:
- introduced a revised method for forecasting and recovering expenditure for SSNS services through a new annual transmission pricing process and revisions to the existing ex-post network support payment pass through process.
- allows (but does not require) TNSPs to seek a determination from the AER that expenditure for a proposed SSNS payment, or methodology for payment, as set out in a draft contract between the TNSP and SSNS provider, will likely be prudent and efficient.
To make this determination, we undertake a rigorous assessment of the application against the National Electricity Rules (NER) criteria. The NER criteria and our general approach to reviewing system security contracts is outlined in the AER’s System security network support payment guideline.