The system operator will use this webpage to publish updates or information related to the Clutha Upper Waitaki Lines Project (CUWLP).
Outage Information
Transpower, as grid owner, has notified outages of the following circuits for the project:
- NSY_ROX_1 and LIV_NSY_1 circuits POCP link
These outages can be viewed on POCP. Any changes to these outages will be communicated via POCP and the usual notification processes.
Industry Briefings and Presentations
- industry briefing 14 December presentation and audience questions.
Energy Trader Forum 12 November 2020 presentation [ pdf 1.58 MB ]- Industry briefing 16 September 2020 presentation [ pdf 1.03 MB ] link.
Recent Updates
13 September 2021
The system operator has published analysis of the power flow limits following completion of the Clutha Upper Waitaki Lines Project (CUWLP). These are the approximate transfer limits and indicative constraints that will apply once the Naseby-Roxburgh and Naseby-Livingstone duplexing is complete. The analysis is based upon the post-CUWLP grid configuration, commissioned generation assets and load profile (including Tiwai load). The results of this analysis are available here [ pdf 203.16 KB ].
11 December 2020
The grid owner has successfully completed the tactical thermal upgrade of the Cromwell-Twizel sections of both CYD_CML_TWZ_1 and 2 circuits.
4 December 2020
The grid owner has completed the tactical thermal upgrade of the Cromwell-Twizel section of the CYD_CML_TWZ_1. The last component of the upgrade to circuit 2 is scheduled for completion during the outage next week.
5 November 2020
The system operator has published its decision on proposed temporary reduction to offload times during Clutha and Upper Waitaki Lines Project outages ( See CAN issued 5 Nov 2020 [ 266.23 KB ])
16 October 2020
The system operator has completed the analysis of system frequency impacts for an islanding event during the CYD_CML_TWZ_1 and 2 circuit for thermal upgrades. A Permanent Manual Constraint has been published which will be used when a single contingency would lead to the separation of the Southland from the remainder of the grid. Refer to the CAN for more details
CAN New Permanent Manual Constraint for GZ14 Export [ 256.59 KB ]
02 October 2020
The grid owner has changed the schedule for outages on CYD_CML_TWZ_1 and CYD_CML_TWZ_2 over the period 16 November to 11 December 2020.
- The 16 to 20 and 23 to 27 November outages on CYD_CML_TWZ_2 will now run continuously from 16 to 27 November.
- The 30 November to 04 December and 7 December to 11 December on CYD_CML_TWZ_1 will now run continuously from 30 November to 11 December.
The weekend outages allow for additional substation work and safer working. If we are able to return the assets to service earlier, we will notify here and via POCP.
Project Progress
In December 2020, Transpower completed the work needed on the Cromwell to Twizel circuits of the Roxburgh to Twizel line. Work continues on the Roxburgh to Livingstone section of the Islington–Roxburgh line.
Customer Advice Notices (CANs)
10 min Offload Times
The system operator has considered the feedback and made a decision on proposed temporary reduction to offload times during Clutha and Upper Waitaki Lines Project outages (Refer CAN [ 266.23 KB ]: 5 November 2020)
- A summary and response to the feedback received is available here [ pdf 105.05 KB ]
- The latest version of Temporary Instruction, (TI-DP-897) which includes the criteria for implementation, is available here [ pdf 177.8 KB ]
Analysis
The system operator has completed analysis of the power flow limits during and after the Clutha Upper Waitaki Lines Project (CUWLP). This identifies the approximate transfer limits and indicative constraints that will apply during and after the various stages of the CUWLP Project. Power Flow Limits - Clutha Upper Waitaki Lines Project (CUWLP) link [ pdf 203.16 KB ].
Questions and Answers
A set of questions we have received from industry along with our responses is available on our CUWLP Q & A page.
Links to Additional Information
Clutha Upper Waitaki Lines Project page
POCP database
Videos that explain how to perform POCP searches and receive notifications of outage changes are available on our Transpower YouTube channel, under the playlist Planned Outage Co-ordination Process
