Green Steel Startup Boston Metal Secures $75 Million, Pivots to Critical Metals Production

Boston Metal, a startup initially recognized for its pioneering efforts in green steel production, has successfully secured a $75 million funding round. This significant investment, exclusively reported by MIT Technology Review, marks a strategic pivot for the company towards the production of critical metals, a move that could be crucial for its long-term survival amidst a shifting landscape of industrial support. While Boston Metal's initial mission focused on decarbonizing steel production – an industry responsible for approximately 8% of global greenhouse gas emissions – the new funding will primarily bolster its critical metals operations. The company's subsidiary, Boston Metal do Brasil, is establishing a commercial facility in Brazil dedicated to producing niobium, tantalum, and tin. CEO Tadeu Carneiro states that this funding will not only support the Brazilian facility's operations but also future endeavors to produce other vital critical metals such as vanadium, nickel, and chromium. The core of Boston Metal’s innovation lies in its molten oxide electrolysis (MOE) technology. This process involves passing an electric current through a reactor containing ore dissolved in a molten electrolyte. The electricity heats the mixture to approximately 1,600 °C (3,000 °F), initiating chemical reactions that efficiently separate the desired metal from the ore. The purified metal then collects at the bottom of the reactor, ready for extraction. In early 2025, the company successfully completed its largest pilot run in Woburn, Massachusetts, producing about a ton of steel. However, the immediate focus has shifted to higher-value critical metals, which command better market prices. This strategic redirection gained urgency after the company faced cash-flow problems earlier this year due to an industrial accident at its Brazilian facility. In January, an issue with the plant’s refractory system led to an electrolyte leak, forcing a shutdown. While no injuries or environmental damage occurred, the incident delayed the plant's official startup, causing the company to miss a funding milestone and subsequently lay off 71 employees in April. The newly acquired $75 million is vital for addressing these challenges. Carneiro confirmed that the funding will alleviate the cash flow stress caused by the delay and support the ongoing repairs at the Brazil facility, which is now expected to commence operations in September 2026. Furthermore, this investment will facilitate other critical metals projects, including plans to establish a US plant for chromium production, a metal almost entirely imported by the country today. With this latest round, Boston Metal's total funding has surpassed $500 million, with support from existing investors and new backing from the prominent Indian steel company Tata Steel Limited. Industry experts, like Seaver Wang from the Breakthrough Institute, suggest that producing higher-value critical metals now can serve as a crucial step to prove the technology's viability and pave the way for future green steel projects, acknowledging that "Nobody wants to pay a green premium for steel—hence niobium."