The strength and reliability of South Australia’s high-voltage electricity network has been boosted with the completion of a project to install four synchronous condensers.

Two synchronous condensers have been installed at Robertstown, north of Adelaide, and two at Davenport, near Port Augusta, with all four now in operation.

Synchronous condensers have a motor whose shaft is not directly connected to anything but spins freely. Its purpose is to adjust technical conditions on the electrical power system.

ElectraNet Chief Executive, Steve Masters, said the growth of renewables within the South Australian power network had created a shortfall in system strength and inertia which needed to be addressed to ensure electricity users continued to receive a secure and reliable power supply.

“As our state’s electricity network continues its transition towards renewable energy sources including wind and solar, we needed to ensure that these sources can be effectively managed and distributed in the grid,” Mr Masters said.

“In the past, system strength has been provided by traditional power sources such as gas-fired units, but as more renewable energy enters the grid, traditional power sources operate less often, creating the shortfall.

“When there is a shortfall, the Australian Energy Market Operator (AEMO) directs generators to address it, which is costly and ultimately adds to a customer power bill.

“Over the past 12 months alone, the cost of these directions has been about $34 million, which is paid for by power customers.

“With the synchronous condensers now in operation, costly AEMO directions can be avoided meaning South Australian residential customers will be saving $3 to $5 per year on a ‘typical’ bill.

Mr Masters said synchronous condensers were complex pieces of infrastructure that have not previously been installed on the South Australian network to this scale.

“These new synchronous condensers play an important role in managing fluctuations in supply or demand and reducing the risk of system instability and supply interruptions,” Mr Masters said.

“With each one weighing in at more than 170 tonnes, eight metres long and more than five meters tall, the work undertaken to install them into our transmission network cannot be underestimated and I thank the project team and contractors who delivered this work.”

Project background

A system strength shortfall was declared by the Australian Energy Market Operator (AEMO) on 13 October 2017 and a shortfall in inertia was declared on 24 December 2018.

A secure power system needs adequate levels of system strength and inertia, which to date have been provided by traditional synchronous generators. A lack of system strength or inertia on the power system brings with it an increased risk of system instability and supply interruptions.

System strength relates to the ability of a power system to manage minor fluctuations in supply or demand while maintaining stable voltage levels, ensuring stable and secure supply for customers.

Inertia relates to the ability of a power system to manage fluctuations in supply or demand while maintaining stable system frequency.

The synchronous condenser project is estimated to cost about $190 million. In August 2019, the Australian Energy Regulator approved funding for the capital cost of the synchronous condensers.

Two synchronous condensers have been installed at ElectraNet’s Davenport substation, near Port Augusta, and two at ElectraNet’s Robertstown substation, about 135km northeast of Adelaide.

Back to News