Origin Energy is investing in energy storage projects across the country to bolster Australia’s renewable future.
Australia’s energy landscape is undergoing a profound transformation, fuelled by a strong commitment to renewable energy and reducing carbon emissions.
At the heart of this shift are large-scale battery storage systems, which help support renewables by storing the energy they produce and then releasing this into the grid at times of peak demand. Batteries can also help maintain security of supply by releasing short bursts of energy that help stabilise the grid.
Origin Energy is positioning itself at the forefront of this transition, spearheading innovative projects that aim to enhance the reliability and efficiency of Australia’s power supply. Among these initiatives are two large-scale battery projects: a 300MW battery at Mortlake Power Station in Victoria, and a 700MW battery at Eraring Power Station in New South Wales.
These projects not only represent significant advancements in energy storage technology but also highlight the evolving role of traditional power stations in the new energy era.
In line with its strategy to lead the energy transition and accelerate the integration of renewable energy and storage into its portfolio, Origin has already invested more than $1.45 billion in these large-scale battery projects over the past few years. This significant financial commitment underscores the Australian energy business’ belief in the critical role that energy storage will play in a decarbonised energy market.
Mortlake Power Station
In August 2024, construction commenced on the $400 million large-scale battery at the Mortlake Power Station in south-west Victoria, with commissioning expected by late 2026. With a capacity of 300MW, the Mortlake battery is expected to deliver an output of up to 650MWh, a key factor in firming up the variable renewable supply and maintaining reliable power for customers.

The Mortlake Power Station is strategically located adjacent to the Moorabool to Heywood 500kV transmission line, and it also sits within Victoria’s South-West Renewable Energy Zone (REZ). Western Victoria is already home to several operating renewable energy generators, and additional new renewable energy developments are expected within the South-West REZ in the coming years.
Origin’s Head of Energy Supply and Operations, Greg Jarvis, said, “The Mortlake Power Station is an ideal site for a large-scale battery being adjacent to the Moorabool to Heywood 500kV transmission line, meaning the battery can utilise existing transmission infrastructure, and support both existing and new renewable energy generation in the area over the coming years.”
Eraring Power Station
Eraring Power Station, another focal point in Origin’s battery storage strategy, is set to undergo a significant transformation. In April 2023, the first stage of a $600 million large-scale battery project began at Eraring, involving the construction of a 460MW battery storage system with a two-hour dispatch duration. This project is on track to be operational by the final quarter of 2025, marking a critical milestone in Origin’s broader strategy to transition away from coal-fired power.
“Eraring is Australia’s largest power station and supplies up to a quarter of the electricity in New South Wales.
“This development is a key step in our plan to transform Eraring for the future as we move toward phasing out coal-fired generation by as early as August 2027.
“Like Mortlake, Eraring was chosen as a strategic site with high-quality connection infrastructure, enabling us to deliver energy into major demand centres,” Mr Jarvis said.
The strategic importance of Eraring as a hub for energy storage was further reinforced in July 2024, when Origin approved the second stage of the Eraring large-scale battery project. This additional $450 million investment will add a further 240MW of capacity with a dispatch duration of four hours. Upon completion, the combined energy storage capacity of both stages will exceed 2GWh, greatly enhancing Origin’s ability to stabilise the grid and support the influx of variable renewable energy.
“Our investments in large-scale batteries at our existing power stations reflect our belief that storage will play a vital role in the evolving grid by firming up the variable supply from wind and solar,” Mr Jarvis said.
“Upon completion, the Eraring battery’s four-hour duration will be capable of absorbing excess solar generation during the day and ensuring reliable energy supply during peak demand in the evening.”
Innovative battery technologies
In addition to its large-scale battery projects, Origin is also exploring innovative technologies that could further enhance its energy storage capabilities. The business has acquired a five percent equity interest in Newcastle-based clean-tech company Allegro Energy and agreed to pilot its water-based, long-duration battery technology at Eraring Power Station.
Mr Jarvis said, “We are pleased to be making an investment in what we view as a very promising technology.
“We believe long-duration storage will ultimately play an important role in the energy mix, and we look forward to watching the progress of this trial and seeing how this technology could complement other storage projects within Origin’s portfolio.”

The agreement with Allegro Energy includes options for Origin to support the company’s growth and development. Once an initial 100kW (800kWh) Redox Flow Battery module is successfully deployed at Eraring, plans are in place to develop a 5MW (60MWh) battery, which could provide 12 hours of energy storage capacity.
Australia’s energy transition is rapidly gaining momentum, with large-scale battery storage systems playing an increasingly pivotal role. Origin Energy’s significant investments in projects like the Mortlake and Eraring batteries, coupled with its exploration of cutting-edge technologies like Allegro’s Redox Flow Battery, demonstrate a forward-thinking approach to the challenges and opportunities of a decarbonised energy market.
As these projects come online, they have the potential to stabilise the grid and support Australia’s renewable energy goals while ensuring a reliable power supply.
Origin’s leadership in this area is not just about adapting to change – it’s about driving it and setting a standard for the industry as Australia moves towards a more sustainable energy future.