Victoria’s State Electricity Commission (SEC) and Italian clean technology company Energy Dome have announced plans to develop the Australian state’s first long-duration compressed carbon dioxide (CO2) energy storage facility.
The project will feature a 20 MW/200 MWh CO2 battery capable of running continuously for ten hours – more than double the roughly four-hour duration of any battery operating in Victoria today.
It will work by drawing CO2 gas from a massive inflatable dome before compressing it into a highly dense liquid at room temperature using excess renewable energy.
The liquid CO2 is then expanded back into a gas through a turbine, which releases electricity as part of a closed-loop system in which the same CO2 continuously circulates rather than being emitted into the atmosphere.
The partners see the use of CO2 as an advantage as there are no lithium or rare earth minerals involved, meaning there is no critical mineral supply-chain exposure.
Unlike conventional lithium-ion batteries, the system can also provide mechanical inertia and other grid support services to help maintain electricity frequency and system strength as coal and gas-fired generation is phased out.
The project will also make use of existing substations and transmission infrastructure in the Latrobe Valley, reducing the need for new grid connections while supporting the region’s transition away from coal.
According to SEC CEO Chris Miller, long-duration energy storage will be critical to stabilise the grid as Victoria works towards its goal of generating 65% of its electricity from renewable sources by 2030.
“As an integrated generator and retailer of 100% renewable electricity to commercial and industrial customers, we envisage long-duration energy storage will play a critical role in balancing our portfolio, enabling SEC to provide additional support to the system during multi-hour or multi-day wind or solar droughts,” he said.
Claudio Spadacini, founder and CEO of Energy Dome, explained that the Latrobe Valley in Victoria is a natural fit for the technology due to its highly skilled workforce. The valley is also transitioning from its traditional role as the state’s brown coal power hub into a diversified advanced manufacturing and renewable energy centre.
“Our CO2 battery delivers 10 to 12 hours of clean, dispatchable power, using proven compressor and turbine technology familiar to the Latrobe Valley workforce. This project will help support the region’s transition from coal while maintaining the engineering skills that have powered Victoria for generations,” he said.
Energy Dome has been delivering capacity at full grid scale since 2025 for utilities and AI data centres. Its global development pipeline now exceeds 30 GWh, with projects underway across Europe, North America, Asia and Australia.
Among them is a 23 MW/200 MWh facility backed by , scheduled to come online in 2028. A separate project is also being developed in partnership with Google in Arizona, while a utility-scale deployment with is helping to integrate intermittent renewable energy into the regional grid.
