Decarbonizing Steel with Green Hydrogen

The steel industry is a cornerstone of modern civilization, providing the essential material for infrastructure, construction, transportation, and manufacturing. However, it remains one of the most carbon-intensive industries, responsible for roughly 7–8% of global CO2 emissions. As the world moves toward net-zero emissions, decarbonizing steel production remains one of the largest unsolved industrial challenges. Green hydrogen — hydrogen produced via electrolysis powered by renewable energy — is the most technically proven pathway available today. This article explores how green hydrogen decarbonizes steel production, and where the industry actually stands in 2026.

The Current Carbon-Intensive Process

To understand the potential of green hydrogen, it's essential first to grasp the current steelmaking process, particularly the blast furnace-basic oxygen furnace (BF-BOF) route, which still dominates global steel production.

The Blast Furnace (BF) process reduces iron ore (Fe2O3) to molten iron using coke as both fuel and reducing agent. The reaction between coke and iron ore produces molten iron and CO2: Fe2O3 + 3CO → 2Fe + 3CO2.

The Basic Oxygen Furnace (BOF) then converts this molten iron into steel by blowing oxygen through it to reduce carbon content — also emitting significant CO2.

This traditional BF-BOF route relies heavily on carbon-based fuels, resulting in substantial emissions. The industry's challenge is producing steel without carbon — and that's where green hydrogen comes in.

The Role of Green Hydrogen in Steelmaking

Green hydrogen replaces carbon in steelmaking primarily through the Direct Reduction of Iron (DRI) method.

Direct Reduction of Iron (DRI) with Hydrogen

DRI, also known as sponge iron, is produced by directly reducing iron ore using a reducing gas, bypassing the need for coke. Traditionally, natural gas has been used as the reducing agent. Green hydrogen can entirely replace it.

The key reaction in hydrogen-based DRI is: Fe2O3 + 3H2 → 2Fe + 3H2O.

Hydrogen reduces iron ore to iron while producing water vapor as the only byproduct — eliminating CO2 emissions from this stage entirely.

Hydrogen in Electric Arc Furnaces (EAF)

After DRI produces sponge iron, it's typically melted in an Electric Arc Furnace to produce steel. EAFs are already relatively low-emission, especially when powered by renewable electricity. Integrating green hydrogen into the DRI-EAF route creates a fully decarbonized production pathway.

Comparing the Three Steelmaking Routes

The H2-DRI-EAF route cuts emissions by roughly 75–95% versus traditional blast furnace production — the largest single decarbonization lever available to the steel industry today.

Technical Challenges and Innovations

While the potential is clear, several technical challenges remain before hydrogen-based steelmaking is viable at full industrial scale.

Hydrogen Production and Availability

Green hydrogen production requires significant renewable electricity. Electrolysis is energy-intensive, and renewable energy availability is the binding constraint on scaling up supply.

Continued innovation in electrolyzer technology — higher efficiency, lower cost — is essential to making green hydrogen viable for steel at scale. Large-scale hydrogen storage and transport infrastructure is equally necessary to supply steel plants with consistent flow; see our guide to hydrogen storage technologies for the tradeoffs across storage methods.

Modification of DRI Plants

Existing DRI plants are typically designed for natural gas, so switching to 100% hydrogen requires modification — reaction kinetics, heat management, and hydrogen distribution systems within the reactor all need optimization, since hydrogen's thermal properties differ from natural gas. Controlling metallization rate (the extent of iron ore reduction to metallic iron) remains key to sponge iron quality.

Economic Considerations

Green hydrogen remains more expensive than natural gas or coal as an input, though the gap continues to narrow. The steel industry operates on thin margins, so viability depends on continued hydrogen cost reduction — achieved through economies of scale, electrolyzer technology improvements, and supportive policy such as carbon pricing.

Case Studies and Pilot Projects

Several projects worldwide have moved from pilot to near-commercial or commercial scale:

• HYBRIT (Sweden) — The SSAB, LKAB and Vattenfall joint venture delivered the world's first fossil-free steel in 2021, since supplying hundreds of tonnes to customers including Volvo and Cargotec for testing, with quality confirmed equivalent to conventional steel. The Luleå demonstration plant is producing thousands of tonnes of hydrogen-reduced iron, with commercial-scale production targeted around 2026.
• Stegra (formerly H2 Green Steel, Sweden) — H2 Green Steel rebranded to Stegra in 2025. The company has secured close to €6.5 billion in funding and received full environmental permit approval for its Boden facility, which is designed to produce roughly 5 million tonnes of green steel annually. Stegra has signed customer agreements with major automotive and industrial buyers including Porsche, Volvo Group, Mercedes-Benz, ZF Group, Scania, and IKEA, alongside iron ore supply agreements with Vale and Rio Tinto — among the clearest signals yet that large industrial buyers are willing to commit to green steel at scale.
• SALCOS (Salzgitter AG, Germany) — Salzgitter has made its final investment decision on SALCOS, securing financing for the full €2.7 billion first-stage investment, including roughly €1 billion in public funding. Groundwork on a 100 MW electrolyser began in early 2025, targeted to produce approximately 9,000 tonnes of green hydrogen annually from 2026. The first direct-reduction plant is scheduled to begin production in the first half of 2027, aiming for up to 95% emissions reduction across the full conversion.

These projects — moving from pilot to secured financing, signed customer contracts, and imminent commercial operation within the same two-year window — mark a genuine shift from feasibility demonstration to industrial deployment.

Future Outlook and Conclusion

The transition to green hydrogen in steelmaking is a transformative opportunity as much as a technical challenge. By decarbonizing one of the most carbon-intensive industries, green hydrogen can play a crucial role in global climate goals — but the transition requires concerted effort across the value chain, from hydrogen production and infrastructure to policy support and industry collaboration.

Green steel currently commands a premium in the market — reported figures range from roughly €50 to €200 per tonne in European transactions, reflecting a market that is still thin, with premiums negotiated bilaterally rather than through transparent spot pricing. As green hydrogen costs continue to fall and production scales, this premium is expected to narrow.

The technical challenges are real but are being actively addressed through the pilot-to-commercial projects above, alongside ongoing innovation in electrolyzer and DRI technology. Hydrogen-based steelmaking is no longer a distant prospect — it's moving into commercial operation within the next 18–24 months across multiple major projects.