Photo: Rondo
Rio Tinto wants to put Australia’s cheap midday electricity to work at its Yarwun alumina refinery, storing it in hot bricks and using that heat battery to produce steam after the sun goes down.
The global mining giant and California-based Rondo Energy have started engineering and design work on a massive heat battery near Gladstone, Queensland. Rondo calls it Australia’s largest planned thermal energy storage project and says it would be a first in the alumina industry.
Alumina is a hard white powder made from aluminum and oxygen that is used to make aluminum metal, sandpaper, and strong ceramics. Globally, aluminum sector refining accounts for approximately 175 million tonnes of carbon dioxide equivalent per year.
It is still in the study stage, but the potential benefit is substantial. Rio Tinto estimates that the battery could supply about 5% of Yarwun’s steam needs and reduce the refinery’s direct emissions by approximately 67,000 metric tons of carbon dioxide per year. It would replace some of the coal and natural gas used to generate steam.
Rondo’s thermal battery uses electricity to heat refractory bricks, which can withstand high temperatures. The bricks retain that energy as heat, which is then used to produce steam for the refinery’s existing steam network.
This is important because industrial heat demand does not stop when solar production falls. Rondo’s heat battery charges during hours when electricity is cheap and plentiful, then continuously supplies heat so factories can keep running.
The proposed Yarwun system would have 360 megawatt-hours (MWh) of thermal storage and deliver up to 30 megawatt-MW of heat. The Australian Renewable Energy Agency (ARENA) lists its electrical load capacity at 78 MW, allowing it to absorb electricity faster than it releases stored energy as heat.
For the refinery, another attraction is that the battery would power the equipment it already uses. The study will evaluate whether that integration can deliver reliable high-pressure steam at a cost that makes sense.
“This project shows how Australia’s abundant energy can be turned into a competitive advantage for the industry,” said Dr Kira Rundel, Rondo Australia Director. “Heat batteries allow manufacturers to use low-cost electricity to produce the reliable heat their operations need 24 hours a day.”
ARENA will provide an initial $3.6 million Australian dollars for the engineering and design study. If the project goes ahead, the agency will provide up to A$38 million for its implementation. There is also a further A$33.3 million in contingency support.
Rio Tinto will match ARENA’s A$3.6 million study contribution. The company says its total investment over the life of the project is expected to exceed ARENA’s funding if the deployment continues.
“Reducing emissions from alumina refining is complex, particularly when it comes to generating the high-pressure steam needed for our operations,” said Armando Torres, managing director of Rio Tinto’s Pacific Operations.
“This study will help us determine whether thermal energy storage can provide a technically and economically viable alternative to fossil fuels for some of Yarwun’s steam needs.”
The feasibility study is expected to take about 12 months.
Read more: Germany uses heated bricks to replace industrial gas boilers
If you have ever considered going solar, make it easy by finding a trustworthy and reliable solar installer near you that offers competitive prices by asking energywise. They have hundreds of pre-vetted solar installers competing for your business, ensuring you get high-quality solutions and save 20-30% compared to going it alone. Plus, it’s free to use and you won’t receive sales calls until you select an installer and share your phone number with them.
Your personalized solar quotes are easy to compare online and you’ll have access to unbiased energy advisors to help you every step of the way. Start here.
FTC: We use automatic affiliate links that generate income. Further.
