Market Notices

Change Number: CHG0110233

Notification issued to: Market Notice
Notification Type: Completed
Change Type: Normal
Service/Component: Identity Service (IDS)
Change Title: Identity Service Site Transfer

Support Information: Report any impacts to the AEMO Information and Support Hub or on External 1300 236 600.

AEMO ELECTRICITY MARKET NOTICE

NON-CONFORMANCE SA1 Region Wednesday, 27 May 2026

AEMO has declared the following unit as non-conforming under clause 3.8.23 of the National Electricity Rules:

Unit: LGAPBS1
Duration: 27/05/2026 10:30 to 27/05/2026 10:35
Amount: -10 MW
Constraint: NC-S_LGAPBS1

Auto-generated on behalf of Manager NEM Real Time Operations

Change Number: CHG0109708

Notification issued to: Market Notice
Notification Type: Completed
Change Type: Normal
Service/Component: Electricity Market Management System
Change Title: EMMS Production Systems will be transferred to the alternative datacentre for maintenance activities .

Support Information: Report any impacts to the AEMO Information and Support Hub or on External 1300 236 600.

Change Number: CHG0110523

Notification issued to: Market Notice
Notification Type: Completed
Change Type: Normal
Service/Component: Gas Hub
Change Title: Gas Retail Initiatives B2B Package 1 ? Production deployment of r46 schema update

Support Information: Report any impacts to the AEMO Information and Support Hub or on External 1300 236 600.

AEMO ELECTRICITY MARKET NOTICE

Cancellation of reclassification of a Non-Credible Contingency Event as a Credible Contingency Event due to Lightning. AEMO considers the simultaneous trip of the following circuits is no longer reasonably possible. There is no longer any lightning activity in the vicinity of the following lines. Accordingly its classification has reverted to a non-credible contingency event.

Region: SA1

Lines: Penola West - South East 1 132kV and Kincraig - Penola West 1 132kV

Cancellation time: 25/05/2026 22:59

Constraint set(s) revoked:
NONE

Refer AEMO Electricity Market Notice 144143

Auto-generated on behalf of Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE

Reclassification of a Non-Credible Contingency Event as a Credible Contingency Event due to Lightning. AEMO considers the simultaneous trip of the following circuits to now be more likely and reasonably possible. Accordingly AEMO has reclassified it as a credible contingency event.

Region: SA1

Lines: Penola West - South East 1 132kV and Kincraig - Penola West 1 132kV

Duration: 25/05/2026 20:55 until further notice

Constraint set(s) invoked:
NONE

Auto-generated on behalf of Manager NEM Real Time Operations

Refer to Market Notice 134696

AEMO has now completed the production of the Murraylink dynamic rating forecast model and the forecasting performance has been satisfactory during the test. AEMO will be enabling the pre-dispatch and PASA formulation using the Murraylink dynamic rating forecast on the following two constraint equations at 1000 hrs on Wednesday 27th May 2026.

VSML_RAT_LIM_DYN
SVML_RAT_LIM_DYN

For full details on the formulation, the updated constraint equations have now been loaded into AEMO's pre-production systems.

Terry Liu
AEMO Operations

AEMO ELECTRICITY MARKET NOTICE

Inter-regional transfer limit variation - Koorangie to Wemen 220 kV Line - VIC region - 25/05/2026

At 1130 hrs 25/05/2026 there was a short notice outage of Koorangie to Wemen 220 kV Line.

The following constraint set(s) invoked at 1130 hrs 25/05/2026
V-KOWE

This constraint set(s) contains equations with the following interconnectors on the LHS.
V-S-MNSP1,T-V-MNSP1,V-SA,VIC1-NSW1

Refer to the AEMO Network Outage Scheduler for further information.

Manager NEM Real Time Operations

The MTPASA results published on 26 May 2026 identifies no Low Reserve Conditions.

MTPASA informs the market of potential reliability issues to allow the market to respond in the first instance, potentially avoiding the need for any AEMO intervention.

For further information on MT PASA, please refer to:
https://www.aemo.com.au/Electricity/National-Electricity-Market-NEM/Data/Market-Management-System-MMS/Projected-Assessment-of-System-Adequacy.

For more information about how AEMO implements the reliability standard, please view the Reliability Standard Implementation Guidelines (RSIG) available on AEMO's website at https://www.aemo.com.au/energy-systems/electricity/national-electricity-market-nem/nem-forecasting-and-planning/forecasting-and-reliability/reliability-standard-implementation-guidelines.

This notice supersedes Market Notice 144116 published on 19 May 2026.

Forecasting

AEMO