Consultation on ST PASA Replacement Project - Reserve Level Declaration Guidelines

AEMO has consulted on the ST PASA replacement project in two stages, Consultation 1 and Consultation 2, to ensure relevant parties have adequate opportunity to engage on the extensive changes to the ST PASA process and procedures.

Consultation 1 was completed in October 2025 with development of a new ST PASA Procedure and minor amendments to the Reliability Standard Implementation Guideline.

This consultation (Consultation 2) was completed on 17 July 2026 and considered the reserve level declaration guidelines and the proposed application of uncertainty measures to load forecasting. Consequential amendments to the supporting procedures were also a part of Consultation 2.

The guideline and procedure are targeted to commence on 31 March 2027.

Scope

This consultation set out AEMO's proposal on inputs, processes and outputs to the ST PASA engine for the purpose of declaring reserve conditions under NER 4.8.4.

AEMO has established the ST PASA Replacement Project under NEM Reform to implement system and procedure changes collaboratively with industry.

In the lead up to the 31 March 2027 targeted commencement date, AEMO will commence developing a parallel run plan targeted to commence in November 2026, an implementation plan, and will publish a new forecasting procedure for ST PASA.