World's most powerful battery goes live at 350 MW

August 06, 2025

Australia’s Waratah Super Battery, operated by BlackRock’s Akaysha Energy, has officially begun operations. Once fully commissioned later this year, it will become the world’s largest battery by power output. 

With an expected capacity of 850 megawatts and 1,680 megawatt-hours, the battery will be able to supply energy to nearly one million homes for one hour. It is designed to stabilize the country’s electricity grid, which is under increasing pressure due to the planned shutdown of coal power plants by 2035.

The battery currently delivers 350 megawatts and is located on the central coast of New South Wales. It will play a key role in smoothing out energy supply, particularly during unexpected outages, according to a statement from the New South Wales government.

“This is the first of our projects to go into operation, and there are many more to come,” said Hannah McCaughey, chief executive officer at EnergyCo, the state agency overseeing the project.

Built to absorb shocks and boost transmission

The Waratah Super Battery is part of the System Integrity Protection Scheme (SIPS), a critical program aimed at preventing energy blackouts and grid instability.

It functions like a giant shock absorber, balancing sudden disruptions in the electricity network. This is particularly valuable as more renewable energy, especially rooftop solar, enters the grid.

Positioned to serve major load centers such as Sydney, Newcastle, and Wollongong, the battery allows more power to flow through existing transmission lines without overloading them.

This reduces the need to curtail renewable energy generation and ensures a more consistent supply of clean electricity. Built on the site of a former coal-fired power station north of Sydney, the facility spans approximately 140,000 square meters, or 14 hectares.

Akaysha Energy has faced several challenges during development, including weather-related construction delays and financial instability at Powin, the battery supplier, which has filed for bankruptcy protection. Despite these setbacks, the company is optimistic about securing more SIPS-related contracts in the future.

“Batteries are now more important than ever to stabilise the grid,” said Akaysha CEO Nick Carter.

Leading the way in utility-scale storage

When fully operational, the Waratah Super Battery will surpass the 750-megawatt Kogan Creek coal-fired generator in Queensland, making it the largest unit of its type connected to Australia’s grid.

While other massive battery projects are still under construction, such as the 700 MW, 2,800 MWh Eraring battery, Waratah is the first to reach this advanced operational stage.

Although Australia was initially behind countries like the United States, China, and Germany in utility-scale battery development, it has recently surged ahead. It now ranks among the top five global markets for large-scale battery storage.

That progress is due in part to the rapid adoption of solar power, which has brought challenges along with benefits. Batteries like Waratah help manage the variability of solar output and maintain a reliable supply during periods of low generation or high demand.

According to data compiled by BloombergNEF, other larger battery projects are in planning or construction phases, but Waratah will lead in terms of power output once completed.

Solar growth and battery synergy

Australia’s leadership in rooftop solar has made large-scale batteries a necessity. With the highest per capita rooftop solar adoption in the world, the country generated 11.2 percent of its total electricity from rooftop systems in 2023.

According to the Clean Energy Council, total rooftop solar capacity hit 20 gigawatts last year. States like New South Wales and Queensland are seeing rapid growth in installations, driven by high solar potential and attractive incentives.

Federal rebates are also boosting interest in home battery systems. As residential and utility-scale storage capacity expands, batteries are helping Australia balance its grid and transition more smoothly away from fossil fuels.

The Waratah Super Battery is a cornerstone of that transition. It not only highlights Australia’s technical capabilities but also reinforces its commitment to a cleaner, more resilient energy future.