ElectraNet adds to upper north South Australian energy grid with powerlines to Oz Minerals mines

The South Australian powerlines infrastructure for the north of Port Augusta to the Gawler Graton and its mines. The red and yellow lines show the lines built by ElectraNet for Oz Minerals. The blue line was to be a shared-cost project with Solar Reserve, developers of the Aurora Solar Energy Project, withdrawn in 2019.
Images courtesy ElectraNet and Creamer Media

A 270-kilometre 275kV long high-voltage powerline was completed in 2020 to Oz Minerals' Prominent Hill and Carrapateena mines plus future operations in the Gawler Craton region of South Australia, north of Port Augusta.

Energy supply became a crucial issue for Oz Minerals and BHP's neighbouring Olympic Dam mine after two-week power cut to the mines after the September 2016 storm.

Both companies planned to grow their copper production in the Gawler Craton but  BHP said it wouldn’t allow OZ to source electricity from its Olympic Dam powerline beyond August 2020.

South Australian electricity transmission specialist ElectraNet built, owned and operated the powerline, with some costs being passed onto OZ Minerals through long-term connection charges.

The new lines, to be manager by SA Power Networks, ran from Davenport to Mount Gunson South, with a switchyard at Mount Gunson South, a 132kV line from the switchyard to Oz Minerals’ Carrapateena mine site and a 132kV line from Mount Gunson South to join an existing 132kV line about eight kilometres north of Olympic Dam.

Oz Minerals previously negotiated sharing the cost of an added shared line to the Aurora solar energy project: a 150MW solar thermal power station 30km north of Port Augusta. SolarReserve, developers of this project, withdrew in 2019 and the site was taken over the 1414 Degrees company, under the SiliconAurora banner, using its TESS-GRID silicon storage technology. The previous concept also was to have a shared-cost line with the Aurora project, running from Davenport south to join with powerlines eventually connecting to the Cultana solar farm on Eyre Peninsula near Whyalla. 1414 Degrees negotiated with ElectraNet to restart the connections.

ElectraNet also was involved in even bigger plans to build South Australia’s  $2.4 billion powerline interconnector to New South Wales with TransGrid.