Electric arc furnaces and the decarbonization of steel
Analyzing electric arc furnace (EAF) emissions using GEM’s unit-level GIST data
The steel industry is navigating a pivotal moment: In the coming years the industry will balance a growing demand for steel with the urgent need to reduce carbon emissions. The accelerating adoption of EAF technology highlights a growing need for detailed unit-level data.
The Global Iron and Steel Tracker (GIST) offers these crucial data on EAF units worldwide. These data aim to support analysts, activists, and industry experts by providing information on development trends, feedstock types, and emissions profiles of EAFs, which are key in understanding the changing steel sector.
Why does EAF steelmaking matter?
The EAF process is known as secondary steelmaking because it uses reclaimed steel and recycles it by melting it down, significantly reducing the need for raw materials. In contrast, primary steelmaking involves producing steel directly from raw materials like iron ore, most often through high-emissions technologies like a coal-based blast furnace.
EAF process emissions comparison
Categorizing steel sector emissions (click to expand)
In calculating greenhouse gas emissions, analysts use three categories.
- Scope 1: “direct” emissions, resulting from onsite processes and fuel use during production at the plant
- Scope 2: resulting from purchased electricity and estimated using the approximate CO2 intensity of the grid supplying the power
- Scope 3: upstream and downstream emissions, e.g. embodied emissions from the purchased scrap steel used in production or downstream in the process
Steel emissions intensities typically include scope 1 and 2 emissions only.
In most production configurations, EAFs emit carbon with far less intensity than the traditional blast furnace-basic oxygen furnace (BF-BOF) steelmaking route. The BF-BOF process, which uses coal as a reducing agent, produces enormous amounts of CO2 — around 2.2 tonnes of CO2/tonne of steel (t CO2/t steel) when including both scope 1 and scope 2 emissions.
In contrast, EAFs cut emissions dramatically when using recycled scrap, which is the dominant feedstock today. However, EAF carbon emissions vary widely depending on each unit’s unique configuration. Considering scope 1 and 2 emissions, EAFs using scrap as the primary feedstock emit around 0.3 t CO2/t steel on average, whereas those using fossil gas-based direct reduced iron (DRI) have higher carbon intensities of around 1.4 t CO2/t steel. There are also several projects underway working to produce EAF steel with net-zero scope 1 and 2 emissions. This involves feeding DRI produced using green hydrogen into an EAF that uses renewable electricity.
With more EAF projects in development over the next decade, it is increasingly important to delve into these various feedstocks and comprehensive emissions evaluations in order to accurately anticipate steelmaking emissions in the future.
Where in the world are EAFs?
Globally, EAFs are distributed more evenly than BF-BOF sites. However, there are still clusters of high-capacity regions of operating EAFs, as well as emerging hubs for EAFs under development.
The role of scrap in EAF steelmaking and implications for the global market
As global EAF capacity grows, the demand for scrap steel is reshaping trade flows and supply chains around the world. Countries with strong scrap resources, like the U.S. and parts of Europe, can produce steel at lower cost and with fewer emissions by relying on this recycled input. But for regions with limited domestic scrap, including much of Southeast Asia, the need for imports drives up costs and impacts local trade balances.
China, which currently relies more heavily on pig iron due to limited scrap supply, is undergoing a transformation of its steel industry with the potential to shape its domestic and international markets substantially. With policies promoting a growing share of EAF production and a maturing scrap economy, China is set to see a significant increase in scrap availability through the rest of the decade — projected to rise by over 50% by 2030. This surge in scrap from the world’s largest steelmaker could reshape global trade flows and encourage China to focus development plans on EAF rather than BF-BOF capacity. As exemplified by just this single country, the international market for steel feedstocks is increasingly complex, with scrap prices and availability influenced by factors like recycling rates and domestic demand shifts.
Understanding these trends is essential for predicting how emissions and costs may change across the steel landscape.
Who are the top EAF steelmakers?
Of top producers, who has transparent EAF data?
While the GIST works to collect the same data on units in every country, there are notable transparency differences between steelmakers. China, the largest EAF operator globally, exhibits substantial gaps in data availability — feedstock information is available for less than 8% of its EAF capacity. This lack of data poses risks to market stability by creating uncertainty about supply chains and by limiting analysis of the industry. It also undermines efforts to assess emissions. In contrast, countries like the United States, Mexico, and South Korea provide more comprehensive coverage of feedstock data, reflecting stronger transparency practices. These differences affect the accuracy of emissions assessments and highlight the need for improved data-sharing.
There are similar gaps in data availability on a company level. While the largest company — Nucor — provides clear feedstock information on 100% of its units, the second largest EAF steelmaking company today, ArcelorMittal, has the lowest data availability of the top ten companies at 49%. This highlights the ability of large companies to provide open information on their units, as well as the need to push some key actors to improve transparency.
Feedstock mix for top producing countries
Feedstocks included:
Click country name to zoom to country breakdown; click up arrow to get back to main view