AEMO ELECTRICITY MARKET NOTICE

AEMO will increase the Heywood test limit from SA to Vic (from the current 550 MW) to 600 MW today to conduct internetwork testing on Heywood.

The following constraint sets will be revoked once the testing criteria met:
I-SV_HEY_550_TEST

The following constraint sets will be invoked:
I-SV_HEY_600_TEST

AEMO will revert the Heywood test limit back to 550 MW once the test has completed while the test result being analysed.

Please also refer to the published formal PEC Stage 1 and HIC capacity release testing information at the following link: https://aemo.com.au/-/media/files/stakeholder_consultation/consultations/nem-consultations/2023/project-energyconnect-stage-1-and-hic-capacity-release/pec-stage-1-and-hic---final-test-program.pdf?la=en.

Terry Liu
AEMO 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

VicGrid has conducted studies and determined that the maximum generation contingency size in Victoria can be increased from 600 MW to 750 MW.

This change affects the generator limitations for prior outage conditions especially in the South-west Victoria area. The new generation limitation for outages is now 750 MW. AEMO has implemented this change in production on 13th May 2026 by updating generation constraints to increase the generation upper limits for outage conditions.

Please refer to the Network Outage Schedule for any upcoming outages in south-west Victoria here.
https://www.aemo.com.au/energy-systems/electricity/national-electricity-market-nem/data-nem/network-data/network-outage-schedule

For further details on this change please refer to VicGrid Limits Advice or contact VicGrid.
vicgrid.com.au/transmission-planning/planning-the-energy-grid

Terry Liu
AEMO Operations

AEMO ELECTRICITY MARKET NOTICE

A network augmentation has been commissioned in the NSW Region.

At 1740 hrs the following equipment was commissioned.

Wagga - Dinawan 6L 330 kV Line
Wagga - Dinawan 6J 330 kV Line
Dinawan 330 kV A and B Buses

Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE

Following a review of the operation of the Very Fast FCAS market, from 5th May 2026 AEMO will increase the cap on dispatch of Very Fast Contingency FCAS in the QLD region from 200 MW to 250 MW, during periods where islanding of the QLD region is considered credible.

No other changes to the dispatch of Very Fast FCAS or FCAS constraint equations will be made on this date.

For more information on the Fast Frequency Response (FFR) initiative, please visit:
https://www.aemo.com.au/initiatives/major-programs/fast-frequency-response

AEMO Operations

AEMO ELECTRICITY MARKET NOTICE.

Update - Lightning vulnerable lines in Tas region

Refer to AEMO Electricity Market Notice 141036

At 1357hrs 11/04/2026 the Farrell -Tribute 220 kV line and Farrell - John Butters 220kV Line tripped.

The cause of the trip was identified as due to lightning.
In accordance with SO_OP_3715, AEMO now considers the Farrell -Tribute 220 kV line and the Farrell - John Butters 220kV line to be vulnerable with a category of probable due to lightning.

Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE


Network Augmentation Commissioned - NSW Region - 01/04/2026

At 1700 hrs 01/04/2026, the Uungula 330 kV Terminal Station has been cut in to the existing Wellington - Stubbo SF 330 kV Transmission Line resulting in the following network augmentations being commissioned:

Uungula 330 kV Terminal Station
Wellington - Uungula 7J 330 kV Transmission Line
Uungula -Stubbo SF 79 330 kV Transmission Line

Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE

The Broadsound - Stanwell No. 856 275 kV line in the Queensland (QLD) region is planned to be out of service from 1800 hrs 28/03/2026 to 2300 hrs 28/03/2026.

This outage is considered a High Impact Outage (HIO) as the outage recall is greater than 30 minutes.
A credible contingency event during this planned outage may require market intervention, such as the issuing of directions.

Refer AEMO Network Outage Schedule (NOS) for further details.

Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE

SERVICE INTERRUPTION

AEMO is experiencing a service interruption relating to: Partial SCADA failure NSW


AEMO is working on restoring the service. AEMO Support Hub will provide updates as more information becomes available.

Dispatch of market targets via SCADA / AGC has failed. Affected participants are requested to enable their backup systems in order to receive dispatch targets and manually follow dispatch targets until further notice. Affected participants are requested to contact the AEMO Electricity Control Room if unable to follow their dispatch targets.

For further enquiries please contact the AEMO Support Hub
Phone: 1300236600 Opt1
Email: [email protected]

Manager NEM Real Time Operations