Sydney Southern Ring

Sydney Southern Ring

Transgrid's Sydney Southern Ring project is a 500 kilovolt (kV) transmission line project from Bannaby to South Creek. It is intended to support the growing demand centres of Sydney, Newcastle, and Wollongong. 

The transmission route would run from Bannaby substation, which would connect into HumeLink in the west and receive renewable energy from the South West Renewable Energy Zone and Snowy 2.0, and transfer this energy into Sydney's west. 

Bannaby substation will also connect via transmission line into Wollar substation in the north, which accesses in the Central-West Orana REZ energy generation.

The scope of the project includes: 


  • constructing a new 114 kilometre, 500 kV double circuit from the existing Bannaby substation to a new substation in the locality of South Creek within western Sydney area
  • cut in existing lines 5A1/5A2, 32 and 38 into the new substation in the locality of South Creek
  • replace a section of existing line 39 to double circuit to connect the new substation in the locality of South Creek to existing Sydney West substation


  • constructing a new South Creek 500/330 kV substation with 2 x 1500 MVA transformers and the associated 500 kV and 330 kV switchbays 
  • augmentation of Bannaby substation to accommodate the new 500 kV double circuit, and
  • augmentation of Sydney West substation to accommodate for additional 330 kV incoming feeder. 

Previous preparations include a Kemps Creek substation expansion. Transfrid have discounted this option in favour of a new South Creek substation. 

Costs include: 

  • Transmission line costs $481 million 
  • Substation costs $283 million 
  • Easement cost, Lines Land cost, Substation $218 million 
  • Bio-diversity cost (TL) $274 million 
  • Site Establishment Costs (Camp Costs) $120 million 

Funding contributions

In December 2022, the Federal and NSW Governments committed $7.8 billion to progress eight critical transmission and renewable energy zone projects in NSW, including the Sydney Southern Ring project. The package is funded by $4.7 billion from the Commonwealth’s Rewiring the Nation plan and $3.1 billion from the NSW Transmission Acceleration Facility.


Procuring Agency: Transgrid


Jun 2022 2022 Integrated System Plan identifies Sydney Southern Ring as an actionable NSW project rather than an actionable ISP project, to progress progress under the Electricity Infrastructure Investment Act 2020 (NSW) rather than the ISP framework.
Dec 2022 A joint $7.8 billion Federal and NSW Government investment is announced for eight projects including the Sydney Southern Ring.
Jun 2023 Transgrid submitted ISP Preparatory Activities – Reinforcing Sydney, Newcastle and Wollongong Supply (Southern Ring) which discards a Kemps Creek substation in favour of a new South Creek substation and confirms project estimate as $1.55 billion.
Estimated Total Cost
Procurement approach
Traditional Procurement |
New South Wales |