System constraints are the result of system parameters. System constraints are designed for the secure operation of the power system within the technical envelope.

System Control issues Risk Notification to meet its obligation to notify participants of changes to the risk.

The table below summarises current long-standing system constraints, which affect system participants in the Darwin-Katherine, Tennant Creek and Alice Springs generation, transmission, and distribution networks.

Risk Notification of duration of less than 1 month and for outage of a single generation/network asset are not published on this page and are managed in line with the Plant Outage Procedure.

The following terminology has been used:

  • OTR: Outage/Testing Request
  • STA: Short Term Advice
  • NRN: Non-Reliable Notice
  • LTRN: Long Term Risk Notice

For more information on the information presented below please contact

RegionID Commencement Date and Time Anticipated End Date and TimeConstraint Constraint Description
Alice Springs OTR 1910997 (LTRN AS V1.0) 13/10/2019 19:00 Until further notice Generation Restriction As a result of Alice Springs System Black on 13 October 2019, Owen Springs Power Station Units 5 - 14 (O5 - O14) are restricted in output until investigations are completed.
Alice Springs N/A N/A Until further notice Generation and Network Restriction OSPS generation output is constrained to a dynamic minimum figure (load dependent) which is real time calculated and displayed in Areva EMS. This is to prevent overloading of Lovegrove Sadadeen Ties 1 or 2 in the event of a contingency.
Darwin-KatherineN/AN/AUntil further noticeGeneration RestrictionTo ensure power system security, stability and reliability is maintained for all users of the power system, System Control has determined that access to testing (inclusive of compliance and commissioning testing) for sites connected to the 132kV Channel Island - Katherine line, will be on the basis of one (1) site/unit at a time with preference given to operational units in line with the Plant Outage Procedure.
Darwin-Katherine OTR 2003064
25/03/2020 6:00 Until further notice Generation Restriction Changes to Minimum Spinning Reserve in Darwin-Katherine Power System.
High levels of Behind The Meter (BTM) solar generation volatility is resulting in frequent Spinning Reserve breaches in Darwin-Katherine Power System.
Darwin-Katherine OTR 2005997 (LTRN DKIS V1.0) 22/05/2020 6:30 31/10/2021 12:00 Generation Restriction Due to low loads forecasted and encountered during the Dry Season period, additional instructions is provided to controllers to assist in meeting dispatch and system security requirements during low loads in range of 60MW – 150 MW.
Darwin-Katherine OTR 2010080 (LTRN DKIS V1.0) 16/11/2020 10:30 Until further notice Generation Restriction The Spray Intercooling (SPRINT) function of generating units at Weddell Power Station (WPS) has been restricted for system security reasons . One SPRINT is to be kept in reserve at all times. This is to only be utilised in the event of:
-  Machine failure to start.
-  Unexpected step increase in load.
-  Unexpected step decrease in generation.
This SPRINT is to be taken offline once appropriate action has been taken to address the relevant shortfall.
Darwin-KatherineOTR 2102021 (LTRN DKIS V1.0)10/02/2021 00:00Until further noticeGeneration RestrictionImposed operating restrictions on all Katherine Power Station generating units such that minimum run time is 6 hours, and minimum downtime is 12 hours (between stopping and starting).
Darwin-Katherine STA D2016/171256 11/07/2015 8:00 Until further notice Generation and Network Restriction Weddell generation output is constrained to a dynamic maximum figure that is dependent on load and calculated in real time. This is to prevent post contingent overloading of network transmission lines. 
Darwin-Katherine STA D2014/75710 28/10/2013 0:00 Until further notice Generation and Network Restriction Pine Creek and Katherine Power System constrained such that the load flow on the most at risk section is minimized. This constraint is only applied when there is an increased risk of tripping for the line due to storms and lightning.
Tennant Creek OTR 1902028 - V1413/12/2019 17:00 Until further notice Generation Restriction Constraints for generation dispatch have been developed based on review of historical events to improve the reliability of the power system against network contingencies..

Last updated 06 Aug 2021 3:08pm