Transgrid has recently published a Project Assessment Conclusions Report (PACR) for managing safety and environmental risks on Line 24 (Vales Point - Eraring).
Spanning a route of 30km, Line 24 is a 330 kV transmission line that runs between Vales Point and Eraring substations. It was originally commissioned in 1969 as part of the line which ran from Vales Point substation to Newcastle substation. The section of Line 24 being addressed by this RIT-T is the single circuit section between the Eraring cut-in and Vales Point substation, a length of approximately 28km. This section is comprised of 79 steel towers.
Line 24 is a key link between two generators on the NSW Central Coast. It will continue to play a central role in supporting the flow of energy to take advantage of naturally-diverse weather patterns, and in the safe and reliable operation of the power system throughout and after the transition to a low-carbon electricity future.
Condition issues that will impact the safe and reliable operation of the network have been found on the line. These raise a number of risks associated with asset failure, including safety and environmental (bushfire) risks. Investment to address the deterioration of the assets along Line 24 due to corrosion is needed to mitigate risks to safety and the environment.
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. Consequently, it is considered a reliability corrective action under the RIT-T.
Transgrid published a Project Specification Consultation Report (PSCR) for managing safety and environmental risks on Line 24 (Vales Point - Eraring) in December 2021.
Transgrid put forward for consideration one technically and commercially feasible option: refurbishing the existing line by remediating or replacing the identified components. This option (Option 1) involves the refurbishment of Line 21 including replacement of asset components, remediation of steelwork and foundations.
No submissions were received in response to the PSCR during the consultation period which closed in March 2022 and no additional credible options have been identified.
Option 1 (line refurbishment) remains the preferred option at this stage of the RIT-T process. This option is estimated to have a capital cost of $8.9 million +/- 25% and is expected to be completed by 2022/23. Transgrid is the proponent of the proposed network project.
In accordance with the requirements of the National Electricity Rules, a summary of the PACR is made available on the AEMO website. A copy of the PACR can be obtained from Transgrid’s website or by emailing RIT-TConsultations@Transgrid.com.au