Steel is the unsung hero of our modern existence. It forms the very skeleton of our cities with its towering skyscrapers, enables our mobility through cars and trains, and is the silent workhorse in countless appliances and tools we rely on daily.
Yet, this cornerstone of progress carries a significant environmental burden. The magnitude of the steel industry's environmental impact is illustrated by its contribution to global greenhouse gas emissions, estimated at 7%, positioning it as a significant emitter demanding urgent and transformative action. (sunviksteels.com)
Among the innovative solutions being explored, green hydrogen stands out as an up-and-coming contender, potentially revolutionising how we manufacture this essential material.
The Heavy Footprint of Traditional Steel
The dominant route for producing steel globally relies on a process known as Blast Furnace – Basic Oxygen Furnace (BF-BOF). This well-established method uses coal and coke as crucial reducing agents to extract iron from iron ore under intense heat.
While effective in yielding vast quantities of steel, this process releases substantial amounts of carbon dioxide (CO2) and other environmentally damaging pollutants into the atmosphere. The sheer scale of the steel industry amplifies this impact, with estimates suggesting it accounts for a staggering 7% of all human-caused greenhouse gas emissions, positioning it as a critical sector demanding immediate and transformative action.
To illustrate the magnitude, a typical blast furnace can emit approximately 1.8 to 2.2 tons of CO2 for every single ton of steel produced.
While an alternative, less carbon-intensive method exists – the Electric Arc Furnace (EAF) – which primarily melts recycled steel scrap using electricity (eoxs.com), it cannot single-handedly meet the ever-increasing global appetite for steel. (recessary.com)
The availability of high-quality scrap steel is inherently limited, and with global demand projected to rise, relying solely on recycling won't suffice. This fundamental constraint underscores the need to discover and implement clean methods for producing new, or "virgin," steel directly from iron ore.
Green Hydrogen: A Breath of Fresh Air for Steelmaking
The emergence of green hydrogen offers hope for decarbonising the steel industry. Unlike traditional hydrogen production, which often relies on fossil fuels in processes that release greenhouse gases, green hydrogen is produced through the electrolysis of water (H2O) using electricity generated entirely from renewable sources like solar, wind, and hydropower.
This clean production method produces very low or even zero carbon dioxide emissions, positioning green hydrogen as a pivotal element in the global transition towards a sustainable energy future.
The Magic of Direct Reduced Iron (DRI)
The key to utilising green hydrogen in steelmaking lies in a well-established process called Direct Reduced Iron (DRI). In this method, iron ore, as lumps, pellets, or fines, is reduced to metallic iron in a solid state at relatively moderate temperatures, typically between 800°C and 1200°C. (bellona.org)
Traditionally, this reduction process has used reducing gases containing carbon derived from natural gas or coal, which still results in CO2 emissions.
However, the primary chemical reaction transforms by employing pure green hydrogen as the reducing gas, yielding only iron and water vapour as a byproduct. This resulting "sponge iron," known as DRI, boasts a high iron content and is then typically melted in an Electric Arc Furnace (EAF) powered by renewable energy to produce near-zero emission steel.
This integrated H2-DRI-EAF pathway is widely recognised as the most promising and strategically important route to achieving deep decarbonization in primary steel production. It's estimated that producing one tonne of direct reduced iron requires at least 54 kg of pure hydrogen. (steelwatch.org)
Pioneering a Greener Path: Global Initiatives
The concept of green hydrogen in steelmaking is rapidly moving from theory to practice, with numerous ambitious pilot projects and large-scale industrial initiatives taking shape worldwide.
The HYBRIT project in Sweden stands as a flagship example. This collaborative effort aims to establish the world's first fossil-free steel production process by replacing coking coal with green hydrogen. Their pilot plant in Luleå has successfully demonstrated the technical viability of using 100% hydrogen for iron ore reduction, and they are targeting industrial-scale production of fossil-free steel by 2026. (hybritdevelopment.se)
Another groundbreaking initiative is H2 Green Steel (now Stegra), also in Sweden (stegra.com). This ambitious project is constructing a fully integrated steel mill in Boden, powered by 100% renewable hydrogen, with operations slated to begin as early as 2025. H2 Green Steel aims for a remarkable 95% reduction in CO2 emissions compared to traditional methods and has already secured significant customer agreements.
Salzgitter AG's SALCOS program in Germany is a phased initiative integrating green technologies. A key component is a large-scale 100 MW electrolysis plant for green hydrogen production, expected to be operational in 2026, with a goal of near carbon-free steel by 2033. (salcos.salzgitter-ag.com)
Global steel giant ArcelorMittal is also actively pursuing hydrogen-based steelmaking across European and Canadian facilities. Their Hamburg project aims for the first industrial-scale production of DRI using 100% hydrogen. (arcelormittal.com)
Under its National Green Hydrogen Mission, India has sanctioned three pilot projects on hydrogen use in steel production, involving companies like SAIL and Matrix Gas. (acuitykp.com)
Additionally, EMSTEEL and Masdar in the UAE have successfully piloted green steel production using green hydrogen.
POSCO in South Korea is planning significant investments in Australia for green Hot Briquetted Iron (HBI) production. (ieefa.org)
The Environmental and Economic Payoffs
The environmental benefits of transitioning to green hydrogen in steel manufacturing are profound. Green steel production has the potential to slash overall emissions by up to 95% compared to traditional methods.
Utilising green hydrogen in the DRI process can save nearly 2 tonnes of CO2 for every tonne of steel produced. This shift also eliminates the reliance on fossil fuels like coal in the iron reduction stage, with water vapour as the primary byproduct. The ultimate goal is near-zero CO2 emissions across the entire steel value chain, provided renewable energy powers all processes.
While green steel currently faces a "green premium" in cost, this is expected to decrease as renewable energy and electrolyser costs fall. Carbon pricing mechanisms and government incentives will also play a vital role in making green steel economically competitive. Studies suggest the green premium's impact on end-product prices, like cars, could be minimal. (europa.eu)
Navigating the Challenges Ahead
Despite the promise, several technological and infrastructural challenges remain.
- The high cost of green hydrogen production is a significant hurdle.
- Ensuring a massive and reliable supply of renewable electricity for hydrogen production and EAFs requires energy storage solutions and grid management.
- Electrolyzer technology is still evolving and needs further scaling. (envirotecmagazine.com)
- Retrofitting existing steel plants for hydrogen-based DRI is complex and costly.
- Careful management is needed to maintain steel quality with H2-DRI, particularly controlling carbon content.
- Building the hydrogen storage, transportation, and distribution infrastructure at scale is also significant.
Looking Towards a Greener Horizon
The future outlook for green hydrogen in steel is optimistic. DRI's role is projected to increase significantly. Green hydrogen will become more available for steelmaking from the mid-2030s. Industries with high emissions are anticipated to adopt green hydrogen at scale. Global green hydrogen deployment capacity is projected to grow substantially. (ing.com)
Government policies and incentives are expected to be pivotal in accelerating this transition.
Several major economies and regions have already implemented or plan to implement supportive frameworks, such as the European Union's Innovation Fund and Horizon Europe initiatives, which provide significant funding for hydrogen-based steel projects.
Similarly, the United States has introduced the Inflation Reduction Act, which includes substantial tax credits and research grants to promote low-emission steel production.
China also uses subsidies to encourage developing and deploying pilot projects focused on green hydrogen and carbon capture and storage within its steel industry.
India's National Green Hydrogen Mission is actively supporting pilot projects exploring the use of hydrogen in various steelmaking processes. The overarching importance of government funding and fostering public-private partnerships in mitigating the financial risks associated with adopting green technologies and facilitating the development of the necessary infrastructure for a hydrogen-based steel industry cannot be overstated.
The steel industry is increasingly setting ambitious targets for reducing greenhouse gas emissions and achieving carbon neutrality. Many major steel producers have publicly committed to achieving net-zero emissions by the middle of the 21st century, aligning with global climate goals.
The industry has also established near-term emission reduction targets, such as the goal of a 45% reduction in emissions intensity for primary steel production by the year 2030, indicating interim milestones on the path to net zero.
Collaborative initiatives like SteelZero are also crucial. They aim to stimulate demand for steel produced with significantly reduced or zero carbon emissions, sending a strong market signal to the industry and encouraging further investment in green technologies.
Conclusion: Forging a Sustainable Legacy
The steel industry is at a pivotal point, facing the challenge of meeting growing demand while drastically reducing emissions. Green hydrogen offers a transformative pathway towards a sustainable future for steel.
While cost, technology, and infrastructure challenges remain, the global momentum behind green steel initiatives is undeniable. Concerted efforts from governments, industry, and researchers are essential to overcome these hurdles.
The successful integration of green hydrogen into steel manufacturing promises to decarbonise a significant industrial sector and contribute significantly to a global sustainable future, forging a legacy of environmental responsibility.
Visit Hydrogenera at https://hydrogenera.eu/ to discover more about the transformative power of Green Hydrogen and how we help shape industries.