Posted on October 12, 2022.

Sandeep Nijhawan brought four business ideas, each addressing rising global temperatures, to his March 2020 meeting with an investor at Bill Gates-founded Breakthrough Energy Ventures. Freshly departed from founding two startups — one on hydrogen, another on batteries — Nijhawan had just seven slides to show. The first pitch in his deck was to make iron without coal, intense heat or emissions, powered by only renewable electricity.

“Let me stop you right there,” BEV investor Dave Danielson told him. “If you could do this thing, then that’s what I would do. I don’t want to hear the next three ideas.”

Iron, of course, makes up 98% of the substance in steel, the ubiquitous material that’s built the modern world. In furnaces heated by coal to more than 1400°C (2500°F), the carbon in coal combines with the oxygen in iron ore to separate out impurities and unwanted oxygen atoms, releasing huge amounts of carbon dioxide.

The iron later goes through a series of steps to be turned into steel, but the iron-creation step accounts for 90% of the greenhouse gas generated. Steel production is responsible for 7% of greenhouse-gas emissions dumped into the air each year — more than the climate impact of shipping and aviation combined. Producing iron at lukewarm temperatures and without coal would skip the most emissions-heavy step without relying on expensive technologies.

That’s why Nijhawan’s idea caught Danielson’s attention: Affordable green steel is a big deal, and could disrupt an industry that generates more than $870 billion in revenues each year. With the green light to go ahead and $2.25 million from BEV and other investors, Nijhawan started Electra — in stealth mode — to do just that.

Putting electrons to work
Stereotypically for a startup, Electra began its experiments in a garage. Nijhawan’s former colleague Quoc Pham joined as chief technology officer. His first job was to figure out whether it’s possible to dissolve iron ore in water laced with acid. Failure came within weeks. “I have bad news for you,” Pham told Nijhawan. “This could be the shortest startup of my life.”

To understand what went wrong, let’s look at the three known ways in which you can cut emissions from steelmaking.

First, capture emissions generated by the process and bury them deep underground. The first such plant was built in 2016 in the United Arab Emirates, but thanks to the upfront expense of carbon-capture technology, none have been built since.

Second, use hydrogen as a replacement for coal. The first shipment of steel made using hydrogen was produced last year, but commercial volumes won’t be available until 2026. And since hydrogen made from renewable electricity is still more expensive than coal, companies are forced to use high-grade iron ore, which there isn’t that much of.

The world is running out of high-grade ores that are available for steelmaking,” says Nijhawan.

Third, use electricity. Metals like aluminum, copper and zinc are made using electricity — admittedly, in much smaller amounts than iron. Until electricity became cheap, it wasn’t economical to think about applying it to iron production.

However, you cannot pass electricity through solid iron ore. One solution is to melt it. That’s what Boston Metal Co., a startup founded in 2012, has done. For the past 10 years, it’s been perfecting and scaling the technology, which works by heating iron ore to 1400°C using enough electricity to power thousands of homes, and concentrating it into a metal box not much bigger than a dumpster.

Concentrating that much electricity into such a small area has to be done using special materials. Boston Metal can achieve it using carbon as an electrode — a piece of equipment that allows energy to flow through without itself melting — but that too generates carbon dioxide, defeating the purpose of using green electricity. Boston Metal found an alternative material made up of iron and chromium, but so far it only works on a pilot scale.

Nijhawan didn’t want to melt anything. Once you have a process running at molten-metal temperatures, it has to run 24 hours and 365 days. If it does stop, the ore solidifies and new vats need to be put in place, causing months of delay. So the process had to be “benign from a temperature perspective,” he says — nothing hotter than the temperature at which “coffee is brewed.” That would allow for easy start and stop, and make it possible to rely on intermittent renewables. But making the process ..

“My pitch to all [the investors] was: ‘Look, I don’t know if this can be done. I’ve thought through the problem and asked the experts. I think there’s a feasible path,” Nijhawan says. “All I need is less than 10 people and maybe a year or year and a half to run this thing to the ground.”

Source: Economictimes