Green Steel Ambitions Tested as Rio Tinto Commits Initial Funds to Zesty Project

Rio Tinto’s Due Diligence Milestone

Australian environmental technology firm Calix Limited has announced that Rio Tinto has completed its due diligence process for the Zesty Green Iron Demonstration Project. This milestone clears the path for Rio Tinto’s initial cash injection of A$3 million, marking a significant step forward in the joint development agreement between the two companies.

Innovative Approach to Green Steel

The Zesty project leverages Calix’s proprietary technology, which uses a combination of electric heating and hydrogen reduction to produce green iron. This method aims to reduce hydrogen consumption and eliminate the need for ore pelletisation, allowing the use of lower-grade iron ores and fines. The technology is designed to be compatible with intermittent renewable energy sources, positioning it as a potentially cost-effective and sustainable solution for decarbonising steel production.

Project Scale and Support

The demonstration plant is designed to produce up to 30,000 tonnes per annum of hydrogen direct reduced iron or hot briquetted iron. It will serve as a toll processing facility for various iron ore types, supporting the viability of Australian iron ore in a low-emissions steel value chain. The project has also secured a substantial grant of up to $44.9 million from the Australian Renewable Energy Agency (ARENA), contingent on matched funding, underscoring government support for industrial decarbonisation initiatives.

Looking Ahead to Final Investment Decision

With detailed design engineering underway, the project is progressing towards a final investment decision expected in 2026. This phase will be critical in determining the commercial viability and scalability of the Zesty technology. The collaboration with Rio Tinto, a global mining giant, adds significant credibility and resources to the endeavour, potentially accelerating the transition to greener steel production in Australia and beyond.

Broader Implications for Industrial Decarbonisation

Calix’s broader mission involves applying its core technology platform across multiple heavy industries to enable renewable-powered processing and emissions capture. The Zesty project represents a tangible step towards industrial sustainability, aligning with global efforts to reduce carbon footprints in traditionally emissions-intensive sectors.