The steel industry is one of the largest industrial sources of global CO₂ emissions. It is estimated that more than 7 per cent of global CO₂ emissions originate from steel production, primarily due to the manufacture of steel from virgin raw materials using carbon-intensive processes. Traditionally, ironmaking relies on coke, coal, natural gas, and other fossil fuels, which serve both as a source of energy and as chemical reducing agents. 

As a result, conventional steelmaking routes generate substantial carbon dioxide emissions, typically in the range of 2.2 to 3.0 tons of CO₂ per ton of crude steel, depending on plant configuration, fuel mix, and operating efficiency. 

The global steel industry is now actively exploring ways to significantly reduce CO₂ emissions while maintaining production efficiency, product quality, and cost competitiveness. At present, most primary steel production is carried out through the Blast Furnace–Basic Oxygen Furnace (BF–BOF) route, which is inherently carbon intensive. 

To reduce dependence on fossil fuels and free carbon, hydrogen and green electricity have emerged as the most viable and scalable alternatives for deep decarbonisation of steelmaking. 

Role of Hydrogen and Green Energy in Steelmaking 

Role of Hydrogen 

Hydrogen can act as a clean and effective reducing agent in ironmaking. When hydrogen is used to reduce iron ore, the by-product is water vapour instead of carbon dioxide, making the process inherently low-carbon. This principle forms the basis of Hydrogen-based Direct Reduced Iron (H₂-DRI) technology, which is gaining global momentum. 

Currently, two major commercial DRI technologies are leading this transition: MIDREX DRI Technology and Tenova–Danieli Energiron DRI Technology. 

Both technologies are capable of operating with high hydrogen concentrations and, ultimately, 100 per cent hydrogen, and claim high metallisation rates, operational flexibility, and improved energy efficiency. 

Role of Green Electricity

Green electricity, generated from renewable sources such as solar, wind, and hydropower, plays a critical role in hydrogen-based steelmaking by:

* Producing green hydrogen through water electrolysis

* Supplying clean power to Electric Arc Furnaces (EAFs), where green or low-emission DRI is melted

* Electrifying downstream processes such as rolling mills, finishing lines, and auxiliary systems 

The availability of low-cost renewable electricity is therefore a key enabler for large-scale steel decarbonisation. 

Decarbonisation Potential 

By adopting hydrogen as the primary reducing agent and replacing fossil-fuel-based energy with green electricity, the steel industry can:

* Eliminate up to 80% or more of fossil-fuel-derived carbon usage

* Achieve deep reductions in CO₂ emissions

* Move closer to net-zero steel production, with CO₂ emissions reduced to below 0.50 tons of CO₂ per ton of finished steel. 

Conclusion

Hydrogen, supported by renewable electricity, represents a transformational solution for decarbonising the steel industry. While challenges remain related to cost, infrastructure development, and large-scale hydrogen availability, the transition away from fossil fuels is both technically feasible and environmentally imperative. 

The future competitiveness and sustainability of the steel industry will increasingly depend on its ability to adopt hydrogen-based ironmaking and green electrified production routes. 

Several large-scale projects currently under installation worldwide are expected to establish clear and replicable decarbonisation pathways for the global steel industry, including: Jindal Steel, Oman; Stegra (formerly H2 Green Steel), Sweden; ThyssenKrupp Steel, Germany and Salzgitter AG, Germany. 

Once commissioned, these plants will serve as benchmark projects, demonstrating the technical and commercial viability of hydrogen-based steelmaking.