Since the Industrial Revolution, the Earth’s average annual temperature has been rising. This is primarily due to increased atmospheric carbon dioxide (CO2) emissions from the burning of fossil fuels. Before the Industrial Revolution, 280 ppm (0.028%) of the atmosphere consisted of carbon dioxide, while in early 2019, this figure had increased to approximately 413 ppm (0.0413%). Figure 1 shows the rise in global annual temperature and the concentration of carbon dioxide on Earth over the past 800,000 years. The atmospheric carbon dioxide data is provided by the National Oceanic and Atmospheric Administration (NOAA). Since there are no direct measurements, the corresponding information is obtained from ice cores from the European Antarctic Ice Core Project (EPICA).
Global warming is actually the result of “too much of a good thing.” Without an atmosphere, the Earth’s surface would be almost frozen. When sunlight enters the atmosphere, it is absorbed by the oceans and continents, thus warming the atmosphere. Most of this heat is then radiated back into space as energy-rich infrared light. This is where “greenhouse gases” come into play. These gases, primarily composed of water vapor, carbon dioxide, and methane, interact with infrared light, preventing them from leaving the atmosphere as they enter space. Thus, the “good thing” happens: the atmosphere retains heat. However, excessive warming has a negative impact, making the atmosphere too warm.
While promoting a clean energy transition, steel is also a significant factor in the world’s current challenges to achieving climate goals. Due to its heavy reliance on coal and coke as fuel and reducing agent, the industry emits approximately 2.6 gigatons of carbon dioxide annually, or about a quarter of industrial carbon dioxide emissions. In addition, 1.1 billion tons of carbon dioxide emissions are due to the use of its exhaust gases and other fuels for power generation and imported heat.
The current high dependence of primary steel production on coal, its long-term capital assets, and the sector’s impact on international trade and competitiveness make the transition to near-zero carbon dioxide emissions challenging. It is for these reasons that the sector is sometimes referred to as one of the “hardest to reduce” sectors.
Meeting the demand for steel products presents a challenge for the steel sector, as it must pursue a more sustainable path while remaining competitive. Therefore, steel producers bear a significant responsibility in reducing energy consumption and greenhouse gas emissions, developing more sustainable products, and improving their competitiveness through innovation, low-carbon technology deployment, and resource efficiency.
Recent research estimates that the global steel industry could find approximately 14% of its potential value at risk if steel organizations fail to reduce their environmental impact. Therefore, decarbonization will be a top priority for maintaining economic competitiveness and preserving the industry’s operating licenses. Furthermore, the lengthy investment cycle of 10 to 15 years, the billions in financing needs, and limited supplier capacity make this issue even more relevant and lock in crucial preparation time to address the decarbonization challenge.
The steel industry has recognized the need for long-term solutions to address CO2 emissions generated during steel production. Therefore, the steel industry has been very proactive in improving energy consumption and reducing CO2 emissions. Since 1975, improvements in energy efficiency have reduced the energy required to produce one tonne of crude steel by approximately 50% in most top steel-producing countries. Further improvements in energy efficiency are being made through the professional and maximal use of state-of-the-art technologies.