Research on the influence of electricity carbon footprint factor on the carbon footprint of steel industry products

The iron and steel industry, serving as a foundational sector of the national economy, represents a significant energy-consuming industry and a major source of global carbon emissions. Against the backdrop of global climate change mitigation and China’s “Dual Carbon” goals, product carbon footprint has evolved into a critical metric influencing international trade and supply chain competitiveness. Owing to its relatively high carbon intensity per unit of product, the Chinese steel industry confronts substantial challenges in pursuing sustainable development. This study employs the Life Cycle Assessment (LCA) methodology to quantify the product carbon footprints of three typical crude steel production routes within representative iron and steel enterprises: the blast furnace–basic oxygen furnace (BF–BOF) long process, the electric arc furnace (EAF) short process utilizing 45% scrap input, and the full-scrap EAF short process. Furthermore, based on the grid emission factor approach, this research calculates and analyzes the annual carbon footprint factors of grid electricity at regional and provincial levels in China from 2018 to 2022. Findings reveal that electricity consumption constitutes a key contributing factor to carbon emissions in steel manufacturing, with the proportion of electricity-related carbon emissions varying markedly across production routes: approximately 7% for the BF–BOF route, around 20% for the EAF route with 45% scrap ratio, and as high as 58% for the full-scrap EAF process. Moreover, significant spatial heterogeneity is observed in regional and provincial electricity generation structures. Regions endowed with abundant hydropower resources, such as Sichuan and Yunnan, exhibit carbon footprint factors below 0.40 kgCO2e·(kWh)?1, whereas those heavily reliant on thermal power generation, including Shanxi and Inner Mongolia, record values exceeding 1.05 kgCO2e·(kWh)?1. This study underscores that strategic optimization of the spatial distribution of steel production capacity, enhancing the share of clean energy in power generation, and expanding EAF-based short-process steelmaking can collectively contribute to reducing the product carbon footprint of China’s iron and steel industry. This study is the first to systematically quantify the influence of electricity carbon footprint factors across different steelmaking processes, providing a reference for planning low-carbon transition pathways in China’s steel industry and for optimizing regional energy structures.