Australia, Victoria: AusNet and Hitachi Energy have joined forces to deliver the grid connection for the Mortlake Battery Energy Storage System, Victoria’s largest grid-scale battery project. The Mortlake BESS, located at AusNet’s Mortlake Power Station, will provide 300 MW / 650 MWh of capacity once operational, supplying equivalent power to around 135,000 homes. The facility is designed to enhance grid stability, store excess renewable energy, and reduce reliance on fossil fuels, supporting Australia’s net-zero by 2050 target.
To enable the connection, Hitachi Energy supplied two 500 kV, 180 MVA transformers engineered for demanding conditions. Featuring upgraded insulation, advanced cooling, and low-loss design, the transformers are built to withstand harsh environments while improving thermal performance and reducing emissions. They are also equipped for digital monitoring, ensuring long-term reliability and efficient operation.
AusNet said the transformers were critical to meeting the project’s tight schedule without compromising on quality or safety. The collaboration involved co-developing technical specifications and contractual arrangements to strengthen supply chain resilience and adapt to evolving project requirements.
The Mortlake BESS will be Victoria’s largest grid-scale battery and one of the most significant in Australia. Once energised, it will help balance variable renewable generation and provide flexible support to the national electricity grid.
AusNet and Hitachi Energy previously worked together on the Golden Plains Wind Farm, where custom-built 500 kV transformers enabled grid connection for Australia’s largest onshore wind project. Both companies view the Mortlake collaboration as another step toward a sustainable energy future.
Source: Hitachi Energy
