Startup just hit a big milestone for green steel production(technologyreview.com)
technologyreview.com
Startup just hit a big milestone for green steel production
https://www.technologyreview.com/2025/03/12/1113130/green-steel-boston-metal/
10 comments
This is reducing iron ore to iron metal. It's making the main input feedstock for all kinds of steels. So yeah, it might be viable as the feedstock for boutique steelmakers that want to claim to be green. But it's going to have to work eventually if we want to get to net zero, or anywhere close.
Iron refining is done with coke, coal, and limestone, calcium carbonate. It produces more carbon than the second step, making steel from the iron metal.
Iron refining is done with coke, coal, and limestone, calcium carbonate. It produces more carbon than the second step, making steel from the iron metal.
Yeah - it's far more complex, and iron != steel.
(The article talks almost entirely about steel (vs. iron), but is too detail-fuzzed to trust that.)
I made very charitable assumption from this:
> Ultimately, the company hopes to license its technology to steelmakers.
Actual steelmakers know all the myriad costs and details and steps required to make steel - and would probably prefer that any radical new process replace as many of those step and details as possible, at an economic cost.
(The article talks almost entirely about steel (vs. iron), but is too detail-fuzzed to trust that.)
I made very charitable assumption from this:
> Ultimately, the company hopes to license its technology to steelmakers.
Actual steelmakers know all the myriad costs and details and steps required to make steel - and would probably prefer that any radical new process replace as many of those step and details as possible, at an economic cost.
By comparison, a blast furnace can produce 4000+ tons a day.
SSAB is completing their new 190-tonne alternate current electric arc furnace by end of next year, which should yield about 500-800k carbon free tonnes of steel plate and coil per year.
They plan to convert all their Nordic plants to carbon free by 2030 and have some plants also in the North America.
https://eurometal.net/ssab-starts-construction-of-eaf-at-oxe... https://www.ssab.com/en/news/2025/03/new-electric-arc-furnac...
They plan to convert all their Nordic plants to carbon free by 2030 and have some plants also in the North America.
https://eurometal.net/ssab-starts-construction-of-eaf-at-oxe... https://www.ssab.com/en/news/2025/03/new-electric-arc-furnac...
Different thing. Electric arc furnaces are old technology.
What is new here is direct reduction of iron ore to iron metal, electrolytically. It makes the input feedstock for your EAFs.
Smelting has always been the most carbon-intensive part of steelmaking.
What is new here is direct reduction of iron ore to iron metal, electrolytically. It makes the input feedstock for your EAFs.
Smelting has always been the most carbon-intensive part of steelmaking.
There's also what's called an electric smelt furnace, that has a couple of variations, currently being trialed by two global scale producers at bigger than MIT lab scale, but less than production:
ESF- https://www.energyinnovation.net.au/article/the-electric-sme...
Fortescue- https://metals.fortescue.com/en/our-projects/green-metal-pro...
BlueScope, BHP and Rio Tinto- https://www.riotinto.com/en/news/releases/2024/bluescope-bhp...
ESF- https://www.energyinnovation.net.au/article/the-electric-sme...
Fortescue- https://metals.fortescue.com/en/our-projects/green-metal-pro...
BlueScope, BHP and Rio Tinto- https://www.riotinto.com/en/news/releases/2024/bluescope-bhp...
Carbon neutral as long as your electricity is carbon neutral.
Also many steel mills are built so that they can switch between energy source, oil, coal, gas, which ever happens to be cheapest currently.
It's a commodity business, price is almost all that matters. And with the current US Administration the days of carbon subsidies might be numbered.
Also many steel mills are built so that they can switch between energy source, oil, coal, gas, which ever happens to be cheapest currently.
It's a commodity business, price is almost all that matters. And with the current US Administration the days of carbon subsidies might be numbered.
With this approach, a waste heat energy recovery system could reuse a significant percentage of the energy.
Big picture - it's like smelting Aluminum, but with Fe instead of Al.* And about 600 °C (1,000 °F) hotter.
On the plus side, Fe is not nearly as fond of oxygen as Al is - greatly reducing the electrical energy needed to reduce the ore to metal.
> The next step is to build an even bigger system, Rauwerdink says—something that won’t fit in the Boston facility. While a reactor of the current size can make a ton or two of material in about a month, the truly industrial-scale equipment will make that amount of metal in about a day. That demonstration plant should come online in late 2026 and begin operation in 2027, he says. Ultimately, the company hopes to license its technology to steelmakers.
From a quick search, it looks like steel is worth ~$500/ton. So calling a 1-2 ton/day system "truly industrial-scale" might be correct language among metallurgical researchers...but it's probably orders of magnitude smaller than you'd need for an economically viable facility.
Maybe start with trying to manufacture some very expensive, low-volume specialty steels?
*EDIT: The usual https://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process , for smelting aluminum, does emit a fair amount of CO2 - because [messy details]. The article basically says nothing about the actual process they're using for iron, ruling out a close comparison.