ElectraNet has published the Project Specification Consultation Report (PSCR) to manage the risk of thermal overload on the 132 kV network between Tailem Bend and Tungkillo.
This PSCR relates to the risk of thermal overloading of the 275 kV and 132 kV network in the transmission corridor between Tailem Bend and Tungkillo under the credible contingency of a trip on one of the two 275 kV lines.
The transmission corridor between Tailem Bend and Tungkillo currently comprises two 275 kV transmission lines in parallel with an underlying 132 kV network. Under the credible contingency of a trip on one of the two 275 kV lines, the remaining 275 kV and/or 132 kV line will be restricted by a thermal overloading limit thereby restricting power flow across the Heywood interconnector below its nominal maximum transfer limitations.
This risk is exacerbated by the connection of new solar and battery energy storage systems (BESS) at Tailem Bend and is expected to become more extreme as additional renewable generation is established near the Tailem Bend area. The risk is currently managed through pre contingent constraints on renewable generation and interconnector flows, particularly during times of high import demand. The current configuration also severely restricts maintenance windows for the existing 275 kV circuits.
The proposed augmentation is to complete a third 275 kV circuit by leveraging committed developments, including establishment of the Tepko Substation (attached to the Summerfield BESS project) and the stringing of the vacant circuit from Tungkillo to Tepko. Stringing the remainder of the vacant circuit from Tepko to Tailem Bend would complete the third circuit through the entire corridor. This is intended to alleviate the 275 kV and 132 kV overload risk, reduce pre contingent constraints, and enable necessary maintenance access.
ElectraNet welcomes written submissions on this PSCR. Submissions are due on or before Tuesday, 30 June 2026. Submissions should be emailed to [email protected].
Submissions will be published on the ElectraNet website. If you do not want your submission to be published, please clearly specify this at the time.