Luxembourg-based steel giant ArcelorMittal has announced that it has invested in US-based Electrified Thermal Solutions (ETS) through its XCarb® Innovation Fund, a vehicle launched in 2021 to support disruptive technologies for steel decarbonization.
Joule Hive™ thermal battery in steelmaking
ETS has developed the Joule Hive™ Thermal Battery (JHTB), a system made of electrically and thermally conductive firebricks contained within an insulated steel unit. It charges by passing renewable electricity directly through the firebricks, storing low-cost, carbon-free thermal energy at temperatures of up to 1,700°C. The stored heat is released by circulating air or gas through channels, delivering high-temperature energy for industrial processes.
High-temperature heat is widely required in steelmaking, including in blast furnace hot stoves, slab reheating before rolling, and finishing processes such as quenching and annealing. At present, these processes typically rely on fossil fuels such as steel plant gases or natural gas. The JHTB therefore offers potential to decarbonize critical stages of the steel production chain.
Demonstration plant under construction
A 5MWh demonstration plant is currently under construction at the Southwest Research Institute in Texas, with commissioning scheduled for late 2025.
Alongside the investment, ArcelorMittal has signed an MoU with ETS to conduct validation tests at its GasLab facility in Asturias, Spain, and explore pilot-scale deployment across its global operations.
Strategic importance for decarbonization
ArcelorMittal stressed that electrifying high-temperature heating is essential to reducing fossil fuel dependence.
ETS added that collaboration with ArcelorMittal could accelerate commercialization, offering a low-disruption, cost-effective route to decarbonizing one of the hardest-to-abate industries.
