Steel manufacturing is responsible for approximately 8% of the emissions driving global climate change. This essential industry underpins the modern economy, yet it presents significant challenges when it comes to reducing its carbon footprint.

With countries worldwide striving to lessen their environmental impact and adopt more sustainable production practices, developing methods to eliminate carbon from the metals sector will be a crucial step toward achieving these goals.

Boston Metal is a startup pioneering a novel technology designed to tackle this issue. Having previously received support from Breakthrough Energy Ventures, a fund established with backing from Bill Gates, the company has recently secured roughly $50 million in a financing round totaling approximately $60 million, as reported in a filing with the Securities and Exchange Commission.

Consulting firm McKinsey & Co. estimates that the global steel industry could see around 14% of its potential value compromised if it fails to address its environmental impact.

Boston Metal, which initially raised $20 million in 2019, employs a technique known as molten oxide electrolysis (“MOE”) to create steel alloys—and ultimately, to produce steel with zero emissions. According to Tadeu Carneiro, the company’s chief executive, the initial portion of this funding was received in December 2018, two years prior to the most recent financing round.

Since its last funding round, Boston Metal has expanded from a team of eight to nearly 50 employees. The Woburn, Massachusetts-based company has also demonstrated the ability to consistently operate its three pilot production lines for metal alloys for periods exceeding one month.

While steel production remains the long-term objective, the company is nearing commercialization with its alloy program, as it is less dependent on established infrastructure and existing investments, according to Carneiro.

Carneiro stated that Boston Metal’s technology represents a fundamental shift in an industry that has seen limited technological advancements since the beginning of the Iron Age around 1200 BCE.

The company’s ultimate vision is to function as a technology provider, licensing its technology and selling components to steel manufacturers or engineering firms that will then produce the steel.

Boston Metal’s immediate plans include establishing a semi-industrial cell line in Woburn by the end of 2022, with the aim of having a fully operational demonstration plant by 2024 or 2025. “At that stage, we will be positioned to commercialize the technology,” Carneiro explained.

Previous investors, including Breakthrough Energy Ventures, Prelude Ventures, and The Engine—an MIT-affiliated “hard-tech” investment firm—participated in this latest funding round. They were joined by Devonshire Investors, the private investment arm of FMR, the parent company of financial services leader Fidelity, which co-led the deal alongside Piva Capital and another investor who has not been publicly identified.

As a result of this investment, Shyam Kamadolli will join the company’s board of directors, as stated in the SEC filing.

MOE transforms metals from their raw oxide form into molten metal products. Developed at the Massachusetts Institute of Technology and based on the research of MIT Professor Donald Sadoway, Boston Metal creates molten oxides specifically designed for particular feedstocks and desired products. Electrons are utilized to melt the mixture and selectively reduce the target oxide. The resulting purified metal collects at the bottom of a cell and is extracted through a process adapted from blast furnace technology. The extraction point is then sealed, and the process continues.

The company highlights the technology’s scalability as a key benefit. Production capacity can be increased as demand for alloys grows.

“Molten oxide electrolysis is a versatile platform technology capable of producing a wide range of metals and alloys, but our initial industrial applications will focus on ferroalloys as a stepping stone toward our ultimate goal of steel production,” Carneiro said in a statement announcing the company’s $20 million financing in 2019. “Steel is a fundamental material in modern society, but its current production methods generate over two gigatons of CO₂. While the basic steelmaking process has remained unchanged for millennia, Boston Metal is disrupting this paradigm by substituting coal with electrons.”

Bill Gates himself has emphasized the importance of decarbonizing the metals industry.

“Boston Metal is developing a method to produce steel using electricity instead of coal, maintaining its strength and affordability,” Gates wrote on his blog, GatesNotes. He also added a caveat: “However, electrification only contributes to emission reductions if it utilizes clean energy sources, which underscores the importance of achieving zero-carbon electricity,” he noted.