The climate cost of the steel industry

An environmental legacy

Steel has been a fundamental pillar of societal, economic and technological development. Its versatility, durability and strength has given steel a crucial role for building infrastructure, manufacturing machinery, and transport, among other key sectors. Steel’s ubiquity has shaped society and our built environment as we know it. However, as societies have advanced and the steel demand has increased, so have the greenhouse gas emissions associated with its production. This phenomenon has led to growing concern about the environmental impacts of the industry and the urgent need to implement sustainable solutions (Hadler et al., 2023; Liu et al., 2020). Traditional steel production, which relies heavily on coal, has contributed significantly to climate change, emitting large amounts of CO₂ and other local pollutants (Olmez et al., 2016; Suer et al., 2022). This article explores some of the environmental implications of steel production and examines emerging technologies that are transforming this sector towards a more sustainable and environmentally friendly model.

Understanding the environmental costs of steel production

The global economy relies on the yearly supply of around 1,8 Giga tonnes of iron steel for the provision of construction materials (~50%), mechanical and electrical equipment, and appliances (~19%) and transport (~15%) and many other applications that positively impact our daily life (Hadler et al., 2023; “World Steel in Figures 2023,” n.d.). While steel manufacturing remains indispensable to modern society, its sustainable and efficient production demands a delicate balance of innovation, investment, and strategic foresight to overcome the challenges it faces. Society’s reliance on steel also comes at environmental costs, which can be traced back to the combustion of coal to satisfy the energy requirements, and to the molten iron phase (Liu et al., 2020; Olmez et al., 2016).

In fact, the iron and steel industry is one of the world’s biggest energy-consumers due to the high temperatures required during the production process (Suer et al., 2022). Due to its high energy use, and the current lack of decarbonization of the energy system, the life cycle greenhouse gas emissions of this industry are found to be in the range of 0,7 to 2,7 kg CO2-equivalent per kg of manufactured steel depending on the manufacturing technology and region (Somers, 2022). Cumulatively, the yearly production of steel accounts then for ~7% of CO2 emissions globally and ~5% (~190Mt of CO₂-equivalent) in the EU (Olmez et al., 2016; Somers, 2022).

Transforming the industry: green initiatives for a carbon-neutral future

Current developments in green steel technologies and the decarbonization of this energy-intensive industry (Somers, 2022; Zang et al., 2023), bring attention to the steps forward the industry is taking to reduce its environmental impacts. Some of these solutions address the optimization in the utilization of scrap steel and molten iron to improve the utilization efficiency of materials and energy (Somers, 2022). However, ultimately, the decarbonization of the steel industry will also require a shift from a fossil coal-based metallurgy towards electricity-based and hydrogen metallurgy (Somers, 2022).

The H2STEEL project is set to address this last specific opportunity through the use of hydrogen and bio-coal from societal waste such as industrial and municipal sludge. The proposed symbiosis of industrial systems will not only promote the decarbonization of the steel industry, but also the recovery of organic carbon and critical raw materials from waste which are crucial to the security of EU’s raw materials. The project proposes a ground-breaking competitive solution for sustainable green hydrogen and biocoal production from circular biowaste streams. It offers a major contribution to the EU Green Hydrogen-economy and the decarbonization of the European Steel sector by offering a disruptive hydrogen production technology, opening a new route for cost-competitive and green hydrogen in Europe.

The H2STEEL project is at the heart of the urgent transformation towards more sustainable steel production. By integrating green hydrogen technologies into the steelmaking process, H2STEEL is expected to contribute significantly to reducing carbon emissions in the industry, following the objectives of the European Green Deal. The proposed innovative approach not only reduces dependence on fossil fuels but also promotes the use of renewable energy, aligning with the vision of a climate-neutrality by 2050.

The importance of stakeholders’ involvement in steel decarbonization

Research institutes, universities, governmental agencies, and technology developers play a key role in developing and implementing new steelmaking technologies. Their collaboration with steel manufactures together with other industries using steel products or managing steel at its end-of-life, plays a crucial role in promoting value chain arrangements for steel circularity and efficient use and recoverability of steel across society.