Market Notices

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: QLD1

Lines: Bulli Creek - Dumaresq 8L 330KV and Bulli Creek - Dumaresq 8M 330KV

Duration: 21/01/2021 23:54 until further notice

Constraint set(s) invoked:
I-QNI_ONE_PHASE_N-2 Constraint set contains the following interconnector(s) on the left hand side:
NSW1-QLD1


Auto-generated on behalf of Manager NEM Real Time Operations

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: QLD1

Lines: Bulli Creek - Dumaresq 8L 330KV and Bulli Creek - Dumaresq 8M 330KV

Cancellation time: 21/01/2021 20:49

Constraint set(s) revoked:
I-QNI_ONE_PHASE_N-2 Constraint set contains the following interconnector(s) on the left hand side:
NSW1-QLD1


Refer AEMO Electricity Market Notice 82277

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: QLD1

Lines: Bulli Creek - Dumaresq 8L 330KV and Bulli Creek - Dumaresq 8M 330KV

Duration: 21/01/2021 18:48 until further notice

Constraint set(s) invoked:
I-QNI_ONE_PHASE_N-2 Constraint set contains the following interconnector(s) on the left hand side:
NSW1-QLD1


Auto-generated on behalf of Manager NEM Real Time Operations

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: QLD1

Lines: Bulli Creek - Dumaresq 8L 330KV and Bulli Creek - Dumaresq 8M 330KV

Cancellation time: 21/01/2021 15:04

Constraint set(s) revoked:
I-QNI_ONE_PHASE_N-2 Constraint set contains the following interconnector(s) on the left hand side:
NSW1-QLD1


Refer AEMO Electricity Market Notice 82274

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: QLD1

Lines: Bulli Creek - Dumaresq 8L 330KV and Bulli Creek - Dumaresq 8M 330KV

Duration: 21/01/2021 14:01 until further notice

Constraint set(s) invoked:
I-QNI_ONE_PHASE_N-2 Constraint set contains the following interconnector(s) on the left hand side:
NSW1-QLD1


Auto-generated on behalf of Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE

Cancellation - AEMO Intervention Event - Intervention dispatch intervals - Direction SA region - 20/01/2021

Refer Market Notice 82265

The AEMO Intervention Event and all associated directions are cancelled from 1500 hrs 21/01/2021

Manager NEM Real Time Operations

AEMO ELECTRICITY MARKET NOTICE

TransGrid has advised AEMO that a number of lines in the Snowy mountains have damaged conductors. To mitigate the risk of conductor failure when the temperature is >40C temperature and wind < 4km/hr the lines will have lower ratings applied in AEMO's systems.

The following constraint sets are available for the application of the revised ratings in pre-dispatch and ST PASA timeframes. In dispatch the dynamic / hand-dressed rating will be used.
N-RED-RAT-PD-ST-2
N-RED-RAT-PD-ST-3
N-RED-RAT-PD-ST-51
N-RED-RAT-PD-ST-65
N-RED-RAT-PD-ST-7

The process for the activation of these revised ratings is TransGrid will monitor forecast conditions at the Cabramurra and Khancoban weather stations and will advise AEMO to apply the revised ratings if the temperatures are forecast to exceed 40C with wind speed lower than 4km/hr. AEMO will then issue a market notice and invoke the constraint sets above.


For full details on the factors these constraint equations and the rating values (modelled as a constant term) are already in AEMO's production systems.

For further details please contact ben.blake@aemo.com.au or Michael.Bradbery@transgrid.com.au

Ben Blake
AEMO Operations

AEMO ELECTRICITY MARKET NOTICE

AEMO's weather service provider has issued forecast temperatures equal to or greater than the NEM Local Temperature Alert Levels for listed weather stations below.

SA
Adelaide West Terrace (39+ Deg C): 24th Jan
Clare High School (39+ Deg C): 23rd Jan, 24th Jan
Mt Gambier Ap (39+ Deg C): 24th Jan
Port Augusta Ap (39+ Deg C): 21st Jan, 23rd Jan, 24th Jan

VIC
Ararat Prison (39+ Deg C): 24th Jan
Latrobe Valley Ap (39+ Deg C): 25th Jan
Melbourne Olympic Park (39+ Deg C): 25th Jan
Mildura Ap (39+ Deg C): 22nd Jan, 23rd Jan, 24th Jan, 25th Jan

The NEM Local Temperature Alert Levels are:

Launceston Ti Tree Bend: 33 Deg C, Dalby Airport: 37 Deg C, for all other selected weather stations: 39 Deg C.

AEMO requests Market Participants to:

1. review the weather forecast in the local area where their generating units / MNSP converter stations are located and,

2. if required, update the available capacity in their dispatch offers or availability submissions consistent with the forecast temperatures.

Further information is available at:

https://aemo.com.au/energy-systems/electricity/national-electricity-market-nem/nem-forecasting-and-planning/forecasting-and-reliability/projected-assessment-of-system-adequacy/nem-local-temperature-alerts

AEMO Operations Planning

AEMO ELECTRICITY MARKET NOTICE

The Moorabool - Haunted Gully and Haunted Gully - Tarrone 500 kV lines in the Victoria (VIC) region is planned to be out of service from 25 February 2021 0500hrs - 3 March 2021 1730hrs.

A credible contingency event during this planned outage could cause synchronous separation of the South Australia (SA) region from the rest of the NEM. If separation occurs, load may be interrupted due to the operation of the Automatic Under Frequency Load Shedding (AUFLS) scheme in SA.

The credible separation contingency is managed as follows:

- When power transfer is from SA to Victoria, contingency lower FCAS will be sourced from SA.
- When power transfer is from Victoria to SA, due to the 47-52Hz island separation frequency band advised by the SA jurisdiction, contingency raise FCAS is not sourced in SA and the AUFLS scheme may respond to low frequency events.
- Power transfer will be restricted on Victoria - South Australia interconnector (Heywood interconnector) to manage system security following the loss of the next contingency.

Forecast capacity reserves in the SA region are currently sufficient to meet electricity demand during the planned outage.

The following constraint sets have been invoked for this outage:

I-VS_050
S-X_BC_CP
V-X_HG_ML_TR

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

Diyoni Hoole
AEMO Operations