Powerlink has recently published a ‘Project Assessment Conclusions Report’ (PACR) to address the secondary systems condition risks at Innisfail Substation.
Innisfail Substation is located approximately 70 kilometres south-east of Cairns in Far North Queensland (FNQ). The site was originally established in the late 1950s as part of the Kareeya Hydro Power Station project to provide electricity to coastal communities in the area. It continues today as a 132/22kV bulk supply point for Energy Queensland’s distribution network for the Innisfail area.
The secondary systems at Innisfail Substation broadly perform the functions of transmission element protection, data collection, remote (and local) control and monitoring. Many of the current systems were installed in 2003 and are reaching the end of their technical service lives, with respective manufacturers slowly withdrawing support and limited spares available. 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 November 2020 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 March 2021. 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.
Following the conclusion of the PSCR, Powerlink completed detailed project planning and coordination with a very large and complex program of works in FNQ. This has identified that the program can only efficiently deliver the works under either option by 2027; not by the required 2024 completion date. Risks in the interim will be managed through a flexible response facilitated by the upfront purchase and fabrication of the new secondary systems under this project. Completion of the works will be scheduled in line with network access availability or completed earlier in the event of failure of the existing equipment.
The PACR recommends implementation of Option2; the full replacement of all secondary systems at Innisfail Substation in a new building by December 2027. The indicative capital cost of this option is $11.63 million in 2020/21 prices. Powerlink is the proponent of this network project. Under this option, initial design work will commence in 2022, with the installation and commissioning of the new secondary systems completed by December 2027
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 firstname.lastname@example.org.
Any enquiries in the first instance should be directed to:
Manager Network and Alternate Solutions