Rondo Energy and Rio Tinto Advance Australia's Largest Thermal Energy Storage Project

GLADSTONE, Australia, Oct. 20, 2026 /PRNewswire/ -- Rondo Energy and Rio Tinto have started front-end engineering and design on the project for a 360 MWh storage / 30 MW discharge Rondo Heat Battery, supported by a grant from the Australian Renewable Energy Agency (ARENA).

ARENA's funding for the project will be provided in stages, with an initial $3.6 million to complete front-end engineering and design work. Following successful completion of that study, ARENA will provide up to $38 million for deployment. ARENA has also approved up to $33.3 million in conditional contingency support, which would only be made available in defined circumstances to manage specific project risks, including cost overruns and electricity costs. 

If progressed, the project would be delivered at Rio Tinto's Yarwun alumina refinery near Gladstone, Queensland and would be one of the first large-scale demonstrations of thermal energy storage for industrial process heat globally, and a world-first for the alumina industry.

Rondo Heat Batteries use abundant, low-cost midday electricity to charge, storing energy as high-temperature heat in refractory brick, and supplying energy as 24/7 continuous process heat to industry. Typically, the heat is delivered as steam, directly into an industrial facility's steam network. Australia regularly has 4-6 hours of surplus solar-generated renewable electricity in the middle of the day, but industrial facilities need heat 24 hours a day, not just when the sun is shining. By charging when electricity is cheap and abundant and discharging continuously, Rondo Heat Batteries turn short periods of low-cost electricity into 24/7 delivery of low-cost steam. 

For energy-intensive industries such as alumina refining, Rondo Heat Batteries create a pathway to electrification that addresses both emissions and energy costs. Because the heat battery slots into the existing steam network, the facility's processes run exactly as before — the only thing that changes is the energy for that heat: no longer from fossil fuels, but sourced from low cost electricity instead. The Yarwun study will assess the technical and economic viability of integrating the technology into refinery operations.

"This project shows how Australia's abundant energy can become a competitive advantage for industry," said Dr. Kira Rundel, Rondo's Head of Australia. "Heat batteries allow manufacturers to use low-cost electricity to produce the reliable, round-the-clock heat their operations need. Australia's largest heat battery will show how factories can cut emissions without increasing energy costs, helping Australian industry to increase global competitiveness and supporting local manufacturing jobs."

Rio Tinto Pacific Operations Managing Director Armando Torres said: "Reducing emissions from alumina refining is complex, particularly when it comes to generating the high-pressure steam needed for our operations.

"This study will help us determine whether thermal energy storage can provide a technically and economically viable alternative to fossil fuels for part of Yarwun's steam requirements.

"The best way to tackle challenges of this scale is through collaboration between industry, government, and technology partners. We welcome ARENA and Rondo's support as we assess technologies that could help reduce our Scope 1 emissions while maintaining reliable operations at Yarwun."

About Rondo Energy

Rondo Energy delivers firm heat and power, including combined heat and power (CHP), to heavy industry and provides power solutions and long duration storage to data centers. For industrial heat applications, Rondo Heat Batteries convert 4-6 hours of low-cost electricity into continuous 24-hour, high-temperature heat, delivered as steam or hot air up to 1,000°C. The heat delivered integrates directly with existing industrial equipment and processes, eliminating on-site emissions and running on lower cost energy. Rondo heat storage can integrate with steam turbines to deliver combined heat and power (CHP) for industry, and long duration power-to-power solutions for large energy consumers such as data centers. Built on proven refractory brick as the thermal storage medium, Rondo's platform is engineered for multi-decade operation in the most demanding industrial environments.

Rondo Heat Batteries have been delivering firm heat and power at scale since 2023, with operational facilities serving customers in fuels and cement (including steam driving turbines for electricity) in the United States and in Asia. The next unit will come online shortly - a 100 MWh Rondo Heat Battery under construction in Europe for a chemical plant. Rondo is a global company based in California, with teams across North America, Europe, the Middle East, and Australia. Providing heat and power solutions to the alumina industry is an area of focus for the company due to the strong fit of Rondo's technology with the heat and power needs of the alumina industry.