Powerlink has recently published a ‘Project Assessment Conclusions Report’ (PACR) to address the secondary systems condition risks at Chalumbin Substation.
Chalumbin Substation is located almost 100 kilometres to the south of Cairns in Far North Queensland (FNQ). The site was established in 1988 to help supply load into the Cairns and Atherton Tableland areas. Planning studies have confirmed there is a long-term requirement to continue to supply the existing electricity services provided by this substation.
The secondary systems at Chalumbin broadly perform the functions of transmission element protection, data collection, remote (and local) control and monitoring. The majority of Chalumbin’s 275kV secondary systems will reach the end of their technical service lives between 2024-2026, with only limited manufacturer support and spares available at this time. Increasing failure rates, along with the increased time to rectify faults due to the obsolescence of the equipment, significantly affects the availability and reliability of these systems and their ability to continue to meet the requirements of the National Electricity Rules (the Rules).
In April 2022 Powerlink published a ‘Project Specification Consultation Report’ (PSCR) identifying the proposed preferred option to address the risks and claiming exemption from producing a ‘Project Assessment Draft Report’ as allowed for under NER Clause 5.16.4(z1).
There were no submissions received in response to the PSCR, which closed in July 2022. As a result, no additional credible options that could deliver a material market benefit have been identified and the outcomes of the economic analysis contained in the PACR remain unchanged from those published in the PSCR.
The PACR recommends implementation of Option 4; the single stage replacement of selected 275kV secondary systems into new panels in the existing building by December 2025. The indicative capital cost of this option is $9.71 million in 2021/22 prices. Powerlink is the proponent of the proposed network project. Under Option 4, design work will commence in 2022, with the installation and commissioning of the new secondary systems completed by December 2025.
In accordance with the requirements of the Rules, a summary of the PACR has been made available on AEMO’s website. A copy of the PACR can be obtained from the Powerlink Website on the RIT-T Consultations page or by emailing email@example.com.
Any enquiries should be directed to:
Manager Network and Alternate Solutions
PO Box 1193
VIRGINIA, QLD 4014
Tel: (+617) 3860 2328