The Australian Energy Market Commission (AEMC) has made a final rule that grants the Australian Energy Market Operator (AEMO) more flexibility to update the short-term projected assessment of system adequacy (ST PASA) so that it remains fit for purpose as the market develops. 

The ST PASA process is the principal method of indicating to the National Electricity Market (NEM) a forecast of power system reliability over a short-term period of seven days. 

The final rule introduces an objective and principles-based approach to ST PASA, providing AEMO with greater discretion in relation to the inputs, information requirements and information that is published in ST PASA.

The final rule also requires AEMO to publish generator availability information for each station and unit. This will improve the information available to the market to enable better decisions regarding availability of plant and scheduling network outages.

The proposed changes are designed to enable AEMO to more effectively incorporate variable renewable energy (VRE) generation, distributed energy resources (DER), virtual power plants (VPP) and battery energy storage systems into ST PASA. The proposed changes may also allow AEMO to more effectively deal with further technology changes in the future.

The final rule is similar to the draft rule published in December 2021. The only substantial difference is that based on advice from AEMO, the implementation date has been changed from quarter 3 2023 to 31 July 2025.