Alinta Energy has brought its 100MW/200MWh Wagerup Battery Energy Storage System (BESS) project into commercial operation in Western Australia. The two-hour battery has been operating commercially since September 2026. It is located at the Wagerup Power Station, approximately 120km south of Perth. The project strengthens electricity supply flexibility across the South West Interconnected System (SWIS), while supporting the integration of renewable energy into the state’s main electricity network. The Hallett BESS project also contributes to Australia’s energy storage capacity.

The project required significant redesign and remediation because of challenging site conditions. In particular, the construction team raised the battery platform and installed substantial retaining infrastructure. These changes addressed site constraints and enabled the project to progress through construction and commissioning. Alinta Energy acknowledged the contribution of its delivery partners and suppliers, although its latest operational announcement did not identify all the companies involved.

Project Delivery and Grid Connection

Alinta initially appointed Shanghai Electric Power Design Institute (SEPD) Australia and Sunterra Pty Ltd to deliver the battery. The project was announced in August 2023, with commissioning originally scheduled for the second half of 2024. However, construction challenges affected the delivery programme.

In September 2025, Alinta selected GenusPlus Group to complete the remaining balance-of-plant works and commissioning. The completion contract was valued at approximately A$50 million. Genus planned to deploy around 100 personnel, with a significant proportion of the work supported by local Western Australian resources.

The battery connects to existing high-voltage transmission infrastructure at Wagerup Power Station. It can discharge up to 100MW and store 200MWh of electricity, allowing it to deliver power at full capacity for approximately two hours. Consequently, it can provide backup capacity and help manage fluctuations in electricity supply and demand across the SWIS.

TheWagerup BESS Project is also part of Alinta Energy’s broader storage development programme in Western Australia. In July 2024, the company secured approval for a separate 300MW battery project at Wagerup. That development includes battery storage units, transformers, high-voltage cabling, a switch room, a control room and supporting infrastructure. It is expected to be completed by October 2027. This second project should be distinguished from the operational 100MW/200MWh facility.

Contribution to Western Australia’s Electricity Network

The Wagerup BESSproject adds dispatchable storage capacity to a power system experiencing increasing levels of solar and wind generation. Battery storage can absorb electricity when supply is high and release it when demand increases or renewable generation declines. This flexibility can help maintain grid stability and reduce pressure on conventional generation during periods of changing demand.

The project also complements Alinta’s existing 392MW gas- and distillate-fired Wagerup Power Station. Together, the facilities provide different forms of generation and storage capacity to support electricity supply across south-western Western Australia.