The carbon intensity of steel measures the average amount of carbon dioxide (CO2) emitted per tonne of steel produced, and considers both primary and secondary steel production. Primary steel production refers to steel produced through the reduction of iron ore which is then processed into steel, while secondary steel production refers to the recycling of scrap steel into useful steel again. It includes direct emissions from fuel combustion, process emissions and indirect emissions from electricity consumption.
The carbon intensity of global steel production has remained fairly steady, although the last five years have witnessed a slight increase. The intensity declined by 2% annually between 2016 and 2018 and then rose by 2% annually in 2019 and 2020. It reached 1,890 kilograms of carbon dioxide per tonne of steel (kgCO2/t) in 2020. The average rate of change over the last five years suggests that global efforts to reduce it are heading in the wrong direction, likely the result of an increased share of blast furnace-based steel production.
If recent trends continue, the carbon intensity of global steel production will continue to rise and the 2030 and 2050 targets will not be reached; the targets require that the carbon intensity declines to 1335-1350 kgCO2/t of steel and 0-130 kgCO2/t of steel, respectively.