“Transformational:” World’s most advanced wind and solar grid can now export and import more power

The first stage of a “transformational” new transmission line that will help propel South Australia – already the world’s most advanced wind and solar state – towards 100 per cent net renewables has officially been switched on.

The first stage of Project EnergyConnect, the country’s largest energy transmission project, runs 135 km from Robertstown in South Australia to Buronga in NSW, with a 24 km spur link to Red Cliffs in Victoria. It was switched on at 10am on Friday.

It will allow an extra 150 megawatts (MW) of electricity to be exchanged between South Australia and its neighbouring states. Once the PEC’s second stage is complete, reaching as far as Wagga Wagga, that transfer capacity will be boosted to 800 MW.

In all, it means that South Australia will be able to import up to 750 MW at any one time, and export up to 700 MW. That will increase to more than 1.3 GW in either direction in late 2027.

That is a significant development for South Australia, which leads the country, and the world, with a share of 72 per cent wind and solar in the last 12 months, and could have achieved more but for the lack of sufficient storage and transmission capacity that has resulted in heavy curtailment of wind and solar at times.

The new transmission link will allow excess wind and solar to be exported to Victoria and NSW, and for more imports when needed, displacing local gas generation. It is key to help the state reach its stated target of 100 per cent net renewables by the end of 2027, when the 900 km transmission project should be complete.

“EnergyConnect is crucial for Australia’s energy transition, unlocking access to more affordable and sustainable renewable energy and reducing consumer reliance on expensive fossil fuels,” Transgrid CEO Brett Redman said in a statement.

“The completion of inter-network testing marks the successful transfer of renewable energy between NSW, South Australia and Victoria for the first time, allowing consumers from the three states to utilise power as we unlock greater energy sharing.”

In reality, the first stage has less to do with Transgrid, which has suffered delays and costs blowouts (from $1.8 billion to $3.6 billion) on its 600 km share of the project, and more to do with ElectraNet, the South Australian based transmission company that achieved its share of the project more or less on time and within budget.

“EnergyConnect is a transformational project for South Australia,” ElectraNet CEO Simon Emms said in a statement.

“The interconnector strengthens South Australia’s position as a leader in the transition to a low-carbon economy and enhances our ability to export our abundance of renewable energy resources.

“The project will significantly strengthen the state’s electricity network and will help make power more reliable, affordable and sustainable for South Australian consumers.”

The completion of the second stage of Project EnergyConnect will also help unlock capacity from the newly created South West renewable energy zone in NSW, although it will fall well short of the potential capacity of the wind and solar and battery projects in the region.

More than 20 GW of projects were bid into a recent auction for “access rights” in the SW REZ, with only 4 GW of capacity available. However, the formal announcement of winners has been delayed (winning projects were privately advised at the start of the year), sparking speculation in the industry as to why.

Some have speculated that there is concern of unforeseen constraints, consideration of using big batteries as “virtual transmission” to unlock more capacity, and fussing over the fact that one of the projects that missed out on the access rights will now not go ahead even though it was successful in the Capacity Investment Scheme.

The PEC is being built with a 330kV line, and many in the industry regret that it wasn’t built with a 500kV line. That would have cost more but delivered vastly more capacity.

As it is, because of the actual and potential blowouts in costs on the NSW side of the project, and in other transmission lines such as Marinus Link, Copperstring, HumeLink, and VNI West, there is also a greater push to leverage existing local networks, whose owners say there is vast capacity available at a fraction of the cost.