Construction has officially begun on an industrial-scale demonstration plant in Linz, Austria, that aims to revolutionize ironmaking with potential net-zero CO₂ emissions. The groundbreaking ceremony, held on September 25, 2025, brought together political leaders and industry representatives, marking a major step forward for green steel technology.
The plant, dubbed Hy4Smelt, will combine Hydrogen-based Fine-Ore Reduction (HYFOR®) technology with an electric Smelter solution, both developed by Primetals Technologies. Scheduled to start operations by the end of 2027, the facility will produce hot briquetted iron, hot metal, and pig iron with a planned capacity of 3 tons per hour. Unlike conventional blast furnaces, HYFOR eliminates the need for agglomeration of iron ore fines and utilizes green hydrogen as a reducing agent, while the Smelter finalizes reduction using renewable energy.
Voestalpine CEO Herbert Eibensteiner emphasized the project’s role in reaching net-zero steelmaking by 2050: “Seeing construction underway of the globally unique Hy4Smelt demonstration plant once again confirms our technological and innovation leadership in green steel production.”
Rio Tinto will supply 70% of the iron ore for the plant and provide technical support, while Mitsubishi Corporation has joined as a strategic co-investor. The initiative also benefits from funding by the Austrian government’s “Transformation of Industry” program, as well as EU-backed initiatives like the Clean Steel Partnership and the Clean Hydrogen Partnership.
Primetals Technologies has been testing HYFOR at a pilot plant since 2021, running over 50 campaigns with various iron ore sources. CTO Alexander Fleischanderl described the new project as “a major step toward net-zero CO₂ emissions in ironmaking,” stressing the urgent need to transition away from coal-fired blast furnaces.
If successful, the HYFOR and Smelter technologies could become commercially available from 2028, offering a scalable pathway to decarbonize global steel production while tapping into low-to-medium grade ores that dominate the world’s supply.
