Work is underway to connect the energy grids in NSW, Victoria and South Australia to improve reliability and security of electricity supply, and allow for future connections from renewable energy sources.
Connecting a 900 km energy interconnector across three states is a massive endeavour, and it is not without significant engineering challenges.
In addition to the obvious issue of the distance involved, the technical scope and design of EnergyConnect, a Critical State Significant Infrastructure project, is ambitious and involves significant new infrastructure and upgrades.
At its core, Australia’s largest transmission project aims to help realise the country’s climate ambitions, but it will also mean tougher competition for consumers, said Gordon Taylor, Executive General Manager – Major Projects at Transgrid.
“EnergyConnect will integrate more affordable and sustainable renewable energy into the national grid, helping to realise Australia’s clean energy transition and net-zero targets,” Taylor explained.
The transmission line is being built between Wagga Wagga in NSW and Robertstown in South Australia, with a connection to Red Cliffs in Victoria, and has been identified as critical to realising the Commonwealth and NSW Governments’ shared vision for a clean energy future.
“It will also ensure that consumers benefit from the lowest possible prices in the wholesale energy market.”
Works underway
The scale of EnergyConnect is huge. The transmission line requires 206 km of new infrastructure in SA and 700 km in NSW. Electranet is responsible for the delivery of the project in SA and Transgrid is responsible for the delivery of the project in NSW.
Within the NSW section, Transgrid has divided the project into two sections. The Eastern alignment is the section from the main hub at the Buronga substation to Wagga Wagga (540 km). The Western section is from Chowilla on the SA/NSW border to Buronga in NSW and from Buronga to Monak at the NSW/Victoria border.
To date, Electranet has completed the South Australia component, from Robertstown to the border, while work continues on the NSW section with the project expected to be completed by 2027, according to Taylor.
Upgrading existing infrastructure
In order for the project to successfully connect the energy grids of the three states, and integrate into the National Electricity Market (NEM), significant works are underway at the three substations.
The main hub is the 16 ha Buronga substation in South-West NSW, which is recognised as one of the largest and most complex substations in the Southern Hemisphere. It has successfully commissioned Australia’s first-ever 330 kV phase shifting transformers, manufactured by Hyosung, each with a capacity of 200 MVA.
It is also the first substation in the world with five phase-shifting transformers running in parallel, which provides improved load sharing, enhanced transmission capacity and reduced congestion. Additionally, two 120 MW synchronous condensers, supplied by Andritz, have been installed to enhance grid stability and support renewable energy integration.
When the first section of the Buronga substation was connected to South Australia in August last year, it required more than 1000 people to create concrete foundations for 505 tower sites; 185 towers were assembled and 90 towers erected on the two lines between Wagga Wagga and Buronga. Since then, work has progressed, with the first stage of the project reaching completion earlier this year.
The second substation, Dinawan, which is near Coleambally NSW, will also play a pivotal role and is equipped with two 120 MW synchronous condensers from Andritz to enhance grid stability and support renewable energy integration.
The third substation is in Wagga Wagga, and has also undergone significant upgrades and expansion to prepare the eastern end of the project for connection to the NSW grid. Works included importing 9,500m³ of fill, building 13 new gantries, supported by 83 concrete piles and 272 foundations, and 6000 hours of testing.
Read more: Transmission tower failures on the increase
Managing expectations
Keeping up the momentum on long-running projects such as this can be challenging and requires more than just good management, it also requires a culture of ownership, adaptability and resilience, Taylor said.
“Engineering success in these projects hinges on the ability to apply lessons learned in real time, evolve with the project, and maintain a shared sense of purpose. When engineers feel empowered to own their work and see its impact, they’re more likely to stay committed and deliver exceptional results.
“Transgrid works hard to ensure our engineering teams are engaged, motivated and focused from inception to completion.”
The second stage of the project will see full transfer capacity of 800 MW released to the NEM with commissioning and full internetwork testing of all network elements from Robertstown in South Australia through to Wagga Wagga in NSW.
“This final stage is planned for completion in late 2026 with full capacity release through internetwork testing by late 2027,” Taylor said. “By strengthening the connections between states, we’re building a more resilient network. This means fewer blackouts and a more stable energy supply, even during disruptions.”
Dr Gabrielle Kuiper outlines how Direct Energy Resources integration could create a minimum of $19 billion in energy system net benefits by 2040.
OMG Megan
Have any of you people given any thought to the human cost of these enormous structures ?
The level of angst and anger being felt by farmers and the farming communities who are directly in the firing line of these monsters is horrendous.
The VNI West proposals in particular, are right now the biggest issue on peoples minds in the Northern Grampians Shire and surrounding areas of country Victoria.
The Victorian Govt is riding rough-shot over people, granting almost unlimited access to private farming land, and it is NOT acceptable.
Peoples livelihoods are being severley impacted, as is their mental health.
Look at the Ballarat events just today, and this is only the tip of the iceberg.
My opinion is that these Govt actions are bordering on Communism, and that Engineers Australia should be taking a step back to seriously consider their support of such a divisive project.
Jamie Bell. Warracknabeal.
I dont get it.
The people currently complaining about the acquisition of easements and visual effects are quite happy to drive on freeways, use water ex dams, go to hospitals,use airports, have power ex someone else’s easement..which are probably all unattractive and on land acquired from people in circumstances just like the current power line acquisitions.