Australia's Largest Battery Goes Live
Perth, Australia — State-owned utility Synergy has completed its Collie Battery Energy Storage System, establishing it as the nation's largest operational battery with 500 megawatts of power and 2,400 megawatt-hours of capacity. Located in Western Australia's Collie region, the project leverages technology from Chinese supplier CATL and bolsters the state's transition from coal to renewable energy sources. Officials announced full operation in early February 2026, according to statements from Synergy and the Western Australian government.
This milestone addresses growing energy demands by storing excess renewable power for peak usage, supporting grid stability amid coal plant retirements. The battery's scale underscores Western Australia's push toward decarbonization, with investments aimed at reducing costs for households and businesses.
Project Specifications and Build Timeline
Synergy constructed the Collie Battery using 640 containerized lithium iron phosphate battery units from CATL, paired with 160 inverter units. The system connects to the South West Interconnected System grid, near the 350-megawatt Collie Power Station, slated for closure in 2027. Construction began in March 2024 and wrapped up in February 2026, as reported by Energy-Storage.news and PV Magazine Australia.
The battery's capacity increased from an initial 2,000 megawatt-hours to 2,400 megawatt-hours, enabling it to power about 785,000 homes for more than four hours, Synergy officials said. Key features include ABB eHouse solutions, 33-kilovolt switchrooms and advanced battery management systems for enhanced grid stabilization.
Notable components consist of:
- 500 megawatts of power output.
- 2,400 megawatt-hours of energy storage, offering 4.8 hours of duration at full power.
- CATL's EnerC containerized lithium iron phosphate technology, rated AAA by PV Tech Research.
Synergy invested more than 1.6 billion Australian dollars in the project, generating about 500 jobs since construction started, according to RenewEconomy and Energy Global.
Rivalry in Collie and Synergy's Growing Portfolio
The Collie region has emerged as a hotspot for battery storage in Australia, with Synergy's project eclipsing Neoen's nearby 2,200-megawatt-hour Collie Battery. Neoen's Stage 1 went operational in October 2024, with Stage 2 scheduled for August 2025 using Tesla Megapack 2XL units, per Energy-Storage.news. A proposed 200-megawatt project further intensifies the area's concentration, fueled by existing power infrastructure and renewable energy potential.
Synergy's battery portfolio now exceeds 3,500 megawatt-hours, including the 100-megawatt, 200-megawatt-hour Kwinana Battery Energy Storage System 1 and the 200-megawatt, 800-megawatt-hour Kwinana 2. The Collie system represents the third grid-scale battery delivered by the Western Australian government in just over three years, officials noted.
Nationally, it surpasses other operational projects like Akaysha Energy's 1,680-megawatt-hour Waratah Super Battery and Origin Energy's 1,770-megawatt-hour Eraring Battery Stage 1, based on reports from PV Magazine Australia and RenewEconomy.
Driving Western Australia's Energy Shift
The Collie Battery aligns with Western Australia's strategy to phase out coal by 2030, particularly with the Collie Power Station's impending 2027 closure. It stores wind and solar energy for release during high-demand periods, facilitating renewable integration into the grid. Energy and Decarbonisation Minister Amber-Jade Sanderson said, "Synergy’s Collie battery will capture wind and solar generation and use it to power homes when needed. Renewable energy generation and storage backed by gas is the least-cost energy mix for households and businesses and will put downward pressure on prices," as quoted in Energy-Storage.news and RenewEconomy.
This development mirrors Australia's broader battery storage surge, driven by the federal Capacity Investment Scheme and state coal retirements. CATL's role highlights its expanding influence in lithium iron phosphate technology amid global supply chain dynamics from China, according to Global Renewable News.
Western Australia Premier Roger Cook remarked, "Collie has played a vital role in powering Western Australia for decades, and under my government, it will continue to do so. Not only is the town now home to Australia’s biggest batteries," per Energy-Storage.news.
Prospects for Grid Reliability and Beyond
Synergy's Collie Battery positions Western Australia at the forefront of battery energy storage, hastening decarbonization on the South West Interconnected System. It promises improved grid reliability as coal facilities retire, potentially offering frequency services and energy arbitrage, though revenue details remain undisclosed.
Future expansions at sites like Eraring and Supernode may rival its size, but Synergy's expanding portfolio signals sustained leadership in the state. Tesla's planned battery remanufacturing facility nearby could enhance servicing for Western Australia and the Asia-Pacific region, as reported by RenewEconomy.
Overall, the battery exemplifies a hybrid renewable-storage-gas model for coal-reliant areas, with analysts viewing it as a blueprint for global energy transitions, according to the Western Australian Energy Minister.