In a statement, ArcelorMittal said the investment in U.S.-based TerraPower is part of a US$830 million equity raise, reportedly the largest private raise among advanced nuclear companies.

TerraPower and technology partner GE Hitachi are building a reactor as part of the U.S. Department of Energy’s Advanced Reactor Demonstration Program near a retiring coal plant in Kemmerer, Wyo. The facility will utilize a cost-competitive sodium fast reactor combined with a molten salt energy storage system.

“This combination will provide clean, flexible energy and integrate seamlessly into power grids with high penetrations of renewables,” ArcelorMittal said.

ArcelorMittal is making the investment through its XCarb Innovation Fund, which is meant to support early stage, breakthrough technologies that have potential to help decarbonize steelmaking.

“Having been in discussions with TerraPower for some time, we have been very impressed by the quality and ambition of the company’s technology and people,” said Irina Gorbounova, head of the XCarb fund.

The XCarb Innovation Fund is designed to invest in the best and brightest innovations which hold the potential to accelerate the world’s transition to net zero and support the decarbonization of our industry, which is intrinsically linked to access to an abundant supply of clean energy solutions. TerraPower is therefore a perfect fit for our Innovation Fund,” Gorbounova said.