Transgrid has published the Project Specification Consultation Report (PSCR) for Managing risk on Line 94U (Parkes - Forbes). Publication of this PSCR represents the first step in the Regulatory Test for Transmission (RIT-T) process.
Line 94U was commissioned in 1986 as Line 94K between Wellington and Forbes. It was cut into Parkes substation in 1992. The northern section, Wellington to Parkes retained 94K line number whilst the southern section, Parkes to Forbes was given the new number 94U. When 94H Manildra to Parkes was built in 2011, the 94U Parkes outlet was rebuilt. The first seven (7) structures out of Parkes are now concrete pole. There are 138 structures between those concrete poles and Forbes.
Detailed analysis of asset condition information indicates that the line has several condition issues which require refurbishment to address its health and maintain appropriate risk levels across the network. These issues primarily concern the wood pole structures which are approaching an end of life condition. This is in spite of the relatively low age, having experienced an accelerated deterioration in asset condition due to use of early vintage Pressure Impregnated (PI) poles on the line.
If action is not taken, the condition of Line 94U is expected to expose us and our customers to increasing levels of risk going forward, as the likelihood of failure increases. There are safety and bushfire risks under the ‘do nothing’ base case, as well as higher expected costs associated with reactive maintenance that may be required under emergency conditions (‘financial risks’). The proposed investment will enable us to manage safety, environmental, reliability and financial risks on Line 94U.
Transgrid manages and mitigates bushfire and safety risks to ensure they are below tolerance levels or ‘As Low As Reasonably Practicable’ (‘ALARP’), in accordance with Transgrid’s obligations under the New South Wales Electricity Supply (Safety and Network Management) Regulation 2014 and Transgrid’s Electricity Network Safety Management System (ENSMS). The proposed investment will enable Transgrid to continue to manage and operate this part of the network to a safety and risk mitigation level of ALARP.
In the PSCR Transgrid has presented two credible network options that would meet the identified need from a technical, commercial, and project delivery perspective. The optimal commercially and technically feasible option presented in this PSCR – Option 2 (Replace all wood pole structures with steel or concrete poles) - is the preferred option to meet the identified need at this stage of the RIT-T.
Transgrid welcomes written submissions on materials contained in this PSCR. Submissions are due on 15 August 2024.
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 regulatory.consultation@transgrid.com.au.