Transgrid has published a Project Specification Consultation Report (PSCR) for managing voltage control in Inner Sydney Metropolitan area. Publication of this PSCR represents the first step in the Regulatory Test for Transmission (RIT-T) process.
Sydney East substation was commissioned in 1976 and forms part of Transgrid’s network serving the Greater Sydney area. It is supplied by two 330 kV feeders (Line 27 and 28) and two 132 kV feeders (Line 92Z and 959) from Transgrid’s Sydney North substation. It supplies ten customer 132 kV lines operated by Ausgrid and two Ausgrid 132 kV transformer tie lines. These 132 kV feeders run between Sydney East substation and Ausgrid substations in the surrounding area, including Kur-ring-gai, Linfield, Warringah, and Willoughby. Sydney East substation is comprised of three 330/132 kV transformers, two 330kV capacitors, one 132 kV reactor and two 132 kV capacitor banks.
The No.1 132 kV reactor at Sydney East substation was first commissioned in 1986 and has reached the end of its serviceable life. The reactor is showing signs of deterioration due to several condition issues, which if not remediated, increase the probability of failure.
The proposed investment, specifically replacing the No.1 132 kV reactor at Sydney East substation, is intended to ensure continued compliance with our Connection Agreement with Ausgrid as set out in Schedule 5.1a and Power Frequency voltage standards in Schedule S5.1a.4 of the NER. The investment will also assist Transgrid to manage and mitigate safety risks that would otherwise arise from failure of the reactor. Consequently, it is considered a ‘reliability corrective action’ under the RIT-T.
Transgrid has identified one credible network option that will meet the underlying need from a technical, commercial, and project delivery perspective. Three other options were considered but not progressed as they were not technically or economically feasible. Option 1 involves replacement of Sydney East No.1 reactor and has an estimated capital cost of $8.82m ($2025/26). Option 1 has been identified as the preferred option that maximises net benefits to participants in the National Electricity Market (NEM).
Transgrid welcomes written submissions on materials contained in this PSCR. Submissions are due on 7 October 2026.
In accordance with the requirements of the Rules, a summary of the Project Specification Consultation Report is made available on the AEMO website. A copy of the PSCR can be obtained from Transgrid’s website or by emailing [email protected].