Zinfra was proud to play a role in upgrading critical infrastructure on Transgrid’s transmission network to unlock the full potential of the NSW Government’s Waratah Super Battery (WSB) Project which began partial operation in August 2025.
As one of the world’s largest battery energy storage systems, the WSB is a 850MW/1680 MWh battery designed to enhance grid stability in the Hunter, Sydney, and Illawarra regions. The battery acts as a “shock absorber” to manage power surges and improve reliability of the electricity network and allow more future renewable energy sources to be integrated. As part of the Waratah Super Battery Network Augmentation, the Zinfra team was appointed by client Transgrid to carry out works across its transmission network to unlock the battery’s full capacity. The team’s role was to:
Modify 16 substations along 800km from Dumaresq to Tumut, replacing high voltage equipment to boost capacity.
Upgrade four major transmission lines from Sydney to Yass—enhancing allowable power to the battery’s 330kV network.
Substation Modifications
The substation works ranged from replacement of sections of high voltage conductor, to changing the majority of the HV equipment and conductors within the substations. The works were often being performed concurrently across six of the substations, with the teams rolling from substation to substation in succession. The works were completed across 140 plus separate outages, with the small sections of the substations electrically isolated. These outages had to consider the network restrictions, the varying durations and scopes within each, requiring all outages to be planned 6 to 12 months in advance of the works. Through meticulous planning and a highly competent management and workforce, over 99% of these outages were completed on time.
Transmission Line Upgrades
The transmission line upgrades involved enhancing four lines between Western Sydney and Yass. To accommodate increased power, our crews were required to lift sections of conductors and, in some cases, install new structures—visible along the Hume Highway. Spanning 211 locations and involving 169 landowners, the works required meticulous planning, advanced outage coordination, and innovative strengthening of 203 towers, often performed live to prevent network interruptions. Environmental considerations were carefully managed, especially near Mundoonen Nature Reserve and Nattai National Park. Thanks to detailed planning and a skilled team, over 99% of outages were again completed on schedule. Proudly modification upgrades of both substation and lines were completed by early June, well in advance of the need date for the WSB and the associated network upgrade.
End to End Services
Working on the project since early 2022, Zinfra provided end to end services from design and engineering to project management and construction. The team delivered more than 300,000 labour hours and zero lost time injuries to significantly increase the power capacity of the 330kV network ensuring the WSB could operate safely and efficiently.
Karl Littlemore, Zinfra’s Project Director said the timeframe and complexity of the projects were two of the key challenges in successfully delivering the project to completion by June 2025.
“With any project of this size, the number of stakeholders, and geographic spread, careful planning, coordination and a seamless integration of team members into the project was paramount,” said Karl.
“Using our in-depth experience, we were able to develop a program with simultaneous construction sites across the network to meet a fast-tracked deadline with no compromise upon the safety of our teams, the communities, and the environment.”
Ryan Palfrey, Transgrid’s Senior Project Manager on the Waratah Super Battery Project, was pleased with Zinfra’s partnership, stating: “Zinfra delivered the works to a high standard and exceeded expectations working with a collaborative approach commercially to close out tasks in a timely manner.
“None of this would have been possible without our incredible team’s innovation, dedication, and teamwork,” said Karl. “We are proud to support the NSW Government and Transgrid prepare for a transition to renewable energy using our expertise to deliver the augmentation project safely and efficiently.”
We wish to thank our client Transgrid for their ongoing support throughout, Aurecon and GHD who performed the substation design, ACG and Maverick who completed civil works on the substations, APD for the transmission line design, Caporn Piling for providing transmission line foundations, and Town and Country who completed the access works.
