SEC Energy Works CO2 Battery (Latrobe Valley)

Executive Overview

The SEC Energy Works CO2 Battery is a planned 20 MW / 200 MWh compressed carbon dioxide energy storage system capable of continuously supplying electricity for 10 to 12 hours, announced in July 2026 by Victoria's State Electricity Commission (SEC) and Italian clean technology company Energy Dome. The project will be Victoria's first long-duration energy storage facility and Australia's first commercial deployment of closed-loop compressed CO2 energy storage. It will be housed at SEC Energy Works, a 143-hectare energy innovation precinct the state-owned SEC is establishing at Hazelwood North in the Latrobe Valley, the historic centre of Victoria's coal-fired generation. Planning and design have begun, with early stakeholder and community consultation underway.

How It Works & Differentiation

Energy Dome's CO2 Battery stores energy through a closed-loop thermodynamic process. During charging, electricity compresses carbon dioxide gas drawn from an inflatable gasholder — the dome — into a liquid held under pressure at ambient temperature; during discharge, the liquid CO2 is evaporated and expanded through turbines to generate electricity, returning the gas to the dome for the next cycle. The system uses no lithium or rare-earth materials, delivers round-trip efficiency above 75%, and exhibits no capacity degradation over a projected 30-plus year operating life. Unlike the lithium-ion systems that dominate Australia's storage fleet, the plant is built from conventional industrial components such as compressors and turbines — equipment familiar to the Latrobe Valley's existing power generation engineering workforce.

Commercialization & Traction

Energy Dome brings an operating commercial track record to the project: its first full-scale plant, a 20 MW / 200 MWh system in Sardinia, Italy, has operated for approximately one year with utility Engie as offtaker. The company was ranked the highest-placed non-lithium supplier on Sightline Climate's January 2026 long-duration storage leaderboard, third overall behind Tesla and Chint Power, and is advancing a global pipeline that includes a 23 MW / 200 MWh project with Google in County Offaly, Ireland, a 19 MW / 190 MWh project with Salt River Project and Google in Arizona targeting 2029 operation, and a 20 MW / 200 MWh project with Alliant Energy in Wisconsin. Energy Dome established its Asia-Pacific headquarters in Melbourne in February 2025 with Victorian Government support, positioning Victoria as its regional deployment base. No commercial operation date or capital cost has been disclosed for the Latrobe Valley project.

Scalability & Strategic Context

SEC chief executive Chris Miller has framed long-duration storage as a system-level requirement as Victoria advances toward its 65% renewable energy target by 2030, enabling the SEC — an integrated generator and retailer of 100% renewable electricity — to support the grid through the multi-hour and multi-day wind and solar droughts that the state's predominantly two-to-four-hour battery fleet cannot cover. The project also carries regional significance: siting Australia's first compressed CO2 storage plant in the Latrobe Valley supports the region's transition away from coal while retaining the mechanical engineering skills base that has served Victoria's power sector for generations. As the anchor deployment at the SEC Energy Works innovation precinct, a successful project would establish a template for pairing state-backed procurement with emerging long-duration storage technologies across Australia's National Electricity Market.