Rio Tinto has committed more than $35 million to support construction of Calix’s Zero Emissions Steel Technology (Zesty) demonstration plant in Western Australia. This investment complements the $44.9 million provided by the Australian Renewable Energy Agency (ARENA) and aims to help the project reach a final investment decision. Rio Tinto will contribute technical support, engineering services, and advocacy to drive progress.
Kwinana Selected as the Site for the Zesty Demonstration Plant
Under the joint development agreement, the demonstration plant will be built at a site in Kwinana, south of Perth. This site had been earmarked for Rio Tinto’s planned BioIron research and development facility and pilot plant. The Kwinana industrial zone offers strong infrastructure, including direct port access, and is located near the NeoSmelt facility. NeoSmelt provides downstream processing potential for direct reduced iron from the Zesty process. Rio Tinto is one of five partners developing the NeoSmelt project, which also received earlier ARENA funding.
How the Zesty Process Supports Low-Emissions Steelmaking
The Zesty technology uses hydrogen reduction and electric heating to create reduced-emissions iron. The process works with lower grade iron ore, creating an opportunity to use Pilbara iron ores in low-emissions steelmaking. This aligns with global industry priorities as steel production continues to be a major contributor to carbon dioxide emissions.
Rio Tinto iron ore chief executive Matthew Holcz highlights the need for innovation.
“We continue to look at a range of ways Pilbara iron ores can help to do this as new technologies emerge,” he said.
Rio Tinto’s Role in Supporting the Zesty Demonstration Project
If the project reaches a final investment decision and completes construction successfully, Rio Tinto will supply up to 10,000 tonnes of Pilbara iron ores. These materials will support commissioning and early testing at the demonstration plant. The company will also facilitate introductions to potential customers interested in downstream applications of Zesty products.
The agreement provides Rio Tinto with a non-exclusive, global, perpetual licence for potential commercial use of the Zesty technology.
Calix chief executive Phil Hodgson says the partnership is pivotal for the project’s development.
“It provides cash and hands-on support, including industry leading resources, expertise and market reach to progress the Zesty demonstration project,” he said.
BioIron Continues to Undergo Research and Development
Rio Tinto has determined that the current BioIron furnace design needs further development to reduce technical risks and improve performance. BioIron is an innovative process that uses raw biomass and microwave energy instead of coal to convert Pilbara iron ore into metallic iron. When paired with renewable energy and fast-growing biomass, the process could cut carbon emissions by up to 95% compared with traditional blast furnace methods.
Rio Tinto continues R&D efforts in collaboration with the University of Nottingham and sustainable technology company Metso.
Mr Holcz reinforces the long-term significance of both technologies.
“Both projects are part of our work to reduce emissions and support the future of iron ore in Australia and the communities that depend on it,” he said.
Growing Momentum for Green Steel in Australia
Green steel technology, including Zesty, plays a vital role in decarbonising a sector responsible for about 8% of global carbon dioxide emissions, according to the International Energy Agency. This shift aligns with Australia’s broader move towards cleaner industrial processes.
The Western Australian Government recently opened an expression of interest for local green steel manufacturers to supply major infrastructure projects. This initiative supports local industry and encourages adoption of low-emissions steel solutions.
WA Premier Roger Cook emphasises the importance of local production.
“Coupled with [the] government’s recent announcement that government will take an ‘if not, why not’ approach to green steel procurement on major government projects, the Zesty green iron demonstration plant will support our efforts to diversify WA’s economy so that it can remain the strongest in the nation,” he said.