Germany’s new public transport infrastructure project, the U5 underground line in Hamburg, is not just a leap forward for urban mobility - it’s also a blueprint for low-carbon construction. Luxembourg-headquartered steelmaker ArcelorMittal has announced that it has supplied 1,100 mt of carbon-reduced rebar to HOCHBAHN U5 Projekt GmbH, supporting the project’s ambitious goal of cutting emissions by 70 percent.
The rebar, branded under XCarb® - recycled and renewably produced, is manufactured using 100 percent renewable energy in an electric arc furnace, resulting in a carbon footprint of around 300 kg carbon per tonne, compared with approximately 2,570 kg carbon per tonne in traditional blast furnace production - a carbon reduction of over 88 percent.
The U5 line is set to connect Hamburg’s eastern and western outer districts with the city center, creating a vital east-west transit link.
“For the U5, we aim to reduce carbon emissions by 70 percent during construction. We only select sustainable materials. ArcelorMittal’s use of recycled scrap and renewable energy makes its steel an ideal fit,” Klaus Uphoff, technical director of HOCHBAHN U5 Projekt GmbH, said. This approach positions the U5 as a model project for integrating low-carbon materials into public infrastructure - potentially influencing procurement standards across Germany.