The global climate crisis is driving an unprecedented transformation of carbon-intensive industrial sectors, among which the steel industry represents one of the most significant challenges. Responsible for more than 7% of global greenhouse gas emissions, steel production plays a crucial role in modern society, providing essential materials for infrastructure, transportation, energy systems, and manufacturing. However, conventional steelmaking processes, largely dependent on fossil fuels and carbon-based reducing agents, generate substantial quantities of carbon dioxide (CO₂), making the sector one of the most difficult to decarbonize. In this context, the concept of green steel has emerged as a strategic pathway to reconcile industrial competitiveness with climate neutrality objectives. This thesis, entitled “Mitigazione della crisi climatica: il ruolo del Green Steel come strategia per ridurre le emissioni di CO₂”, investigates the technological, environmental, economic, and regulatory dimensions of the transition toward low-carbon steel production.

​

The study begins by examining the relationship between climate change and industrial emissions, highlighting the urgency of reducing greenhouse gas emissions in accordance with the goals established by the Paris Agreement and the European Green Deal. Particular attention is devoted to the steel sector, classified among the so-called “hard-to-abate” industries due to the intrinsic dependence of traditional production routes on carbon-intensive processes. The thesis analyzes the current steelmaking technologies and their specific emissions profiles, comparing the conventional blast furnace-basic oxygen furnace route with alternative production pathways based on electric arc furnaces, increased scrap utilization, renewable electricity, and innovative reduction technologies.

​

A central focus of the research concerns the role of hydrogen as a transformative solution for steel decarbonization. The study investigates the potential of green hydrogen, produced through electrolysis powered by renewable energy, as a substitute for coal and coke in direct reduction processes. While hydrogen-based steelmaking presents significant opportunities to reduce direct emissions, the thesis also addresses the technical, economic, and logistical challenges associated with its large-scale deployment. These include infrastructure requirements, renewable electricity demand, hydrogen storage and transportation constraints, safety considerations, and the need for substantial industrial investments. The analysis demonstrates that hydrogen can play a decisive role in reducing emissions, but its effectiveness depends on the development of a broader renewable energy ecosystem and supportive policy frameworks.

​

In parallel, the thesis explores Carbon Capture, Utilization and Storage (CCUS) technologies as complementary strategies for mitigating emissions in existing steel plants. Through a detailed investigation of capture processes and their potential integration into industrial operations, the study evaluates the effectiveness of CCUS in reducing unavoidable process emissions. Particular emphasis is placed on innovative CO₂ capture technologies developed and tested within the academic environment of Politecnico di Torino. Experimental investigations conducted on gas mixtures representative of blast furnace emissions provide valuable insights into the feasibility and performance of emerging capture solutions. The results indicate that although CCUS can significantly contribute to emission reductions, technological maturity, economic viability, and infrastructure development remain critical factors influencing large-scale implementation.

​

Another fundamental aspect addressed in the thesis is the role of circular economy principles in steel decarbonization. Steel is one of the most recyclable materials globally, and increasing the use of high-quality scrap represents a powerful strategy to reduce energy consumption and carbon emissions. The research analyzes the availability, quality, and distribution of scrap resources, emphasizing how efficient recycling systems and enhanced material recovery can contribute substantially to lowering the sector’s environmental footprint. At the same time, the study identifies limitations related to scrap contamination, resource availability, and demand growth, highlighting that recycling alone cannot fully satisfy future steel demand. Consequently, a combination of circular strategies and breakthrough technologies is required to achieve deep decarbonization.

​

The thesis also provides a comprehensive overview of the evolving regulatory and policy landscape supporting the transition toward green steel. Key instruments such as the European Emissions Trading System (EU ETS), the Carbon Border Adjustment Mechanism (CBAM), and international climate policies are analyzed with respect to their capacity to incentivize low-emission production pathways. The research further investigates the emergence of sustainability standards and certification initiatives, including frameworks proposed by organizations such as LESS, ResponsibleSteel, GSCC, and other international stakeholders. A critical finding of the study is that the absence of a universally accepted definition of “green steel” creates significant challenges for market transparency and comparability. The proliferation of different standards and labels may generate uncertainty and increase the risk of greenwashing, underscoring the need for harmonized methodologies based on measurable emission reductions and genuine circularity performance.

​

To contextualize technological and policy developments within broader climate mitigation efforts, the thesis incorporates scenario analysis using the En-ROADS climate simulation model. These simulations illustrate the impacts of various energy, industrial, and policy interventions on future global temperature trajectories. The findings suggest that no single solution is sufficient to address climate change effectively. Instead, meaningful mitigation requires the simultaneous deployment of multiple strategies, including renewable energy expansion, industrial electrification, carbon pricing mechanisms, efficiency improvements, carbon capture technologies, and behavioral changes across society. The results reinforce the importance of coordinated action among governments, industries, researchers, and citizens to limit global warming and achieve long-term sustainability objectives.

​

In conclusion, this thesis demonstrates that green steel represents a crucial pillar in the global pathway toward climate neutrality. While significant technological progress has been achieved, challenges related to scalability, economics, infrastructure, and regulatory harmonization remain substantial. The transition toward sustainable steel production requires an integrated approach that combines hydrogen-based processes, carbon capture technologies, circular economy practices, renewable energy deployment, and transparent sustainability standards. Ultimately, the research highlights that innovation, effective governance, and international cooperation are indispensable for ensuring that the steel industry can remain competitive while contributing meaningfully to global climate mitigation efforts. Through the adoption of these transformative strategies, green steel has the potential not only to reduce industrial emissions but also to serve as a model for the decarbonization of other hard-to-abate sectors, supporting a more resilient and sustainable industrial future.