Steel is one of the most important materials in the world, central to the cars we drive, the buildings we live in, and the infrastructure that allows us to travel from place to place. Steel is also responsible for 7% of global greenhouse gas emissions. In 2021, 45 countries pledged to pursue near-zero-emission steel in the next decade. But how feasible is it to produce the steel we need in society with zero emissions?
A new study focused on the Japanese steel industry shows that if we are truly committed to achieving zero emissions, we must be prepared for a situation where the amount of steel we can produce is lower. Japan has set a target of a 46% reduction in steel emissions by 2030, and zero emissions by 2050. So far, the roadmap to achieve this is largely dependent on future technological innovations. Developments in carbon capture and storage (CCS) and hydrogen-based technologies are expected.
In the study, Dr Takuma Watari, a researcher at the National Institute for Environmental Studies, Japan, who is currently working with the University of Cambridge, argues that there is no silver bullet. He says that current plans to reduce carbon emissions underestimate how difficult it will be to develop and widely deploy CCS and hydrogen technologies: “There are still major technical, economic and social challenges to overcome these technologies, and they have yet to be implemented at scale. most importantly, it is highly uncertain whether there will be enough non-emissive electricity to use these technologies.” We must face the possibility that technological innovations may not be ready in time to allow us to maintain current levels of steel production and reduce emissions to zero.
The research involved mapping the current flows of steel in the Japanese industry and using a model to see how the industry might change if a strict carbon budget were implemented in the future. Dr Watari explains that with current practice, the quantity and quality of steel produced under a zero carbon emissions budget would significantly decrease. This is due to a lack of resources and the practice of downcycling, in which steel scraps containing impurities are used to make new products. It is difficult to remove these impurities, so the new products have a different quality and functionality from the original steel.
According to Dr. Watari, “zero emission steel can be produced by 2050, but in limited quantity and quality compared to the current total production. This is due to the limited availability of compatible zero emission resources and minimum scrap steel recycling practices – steel.”
The research shows that with a carbon budget of zero emissions, the production of steel goods would be severely curtailed compared to today, reaching around half current levels at best. In this case, the production of higher quality steel (eg, sheet steel) would be hit particularly hard.
The implication is clear. Relying on relevant technological silver bullets is not enough to transform the steel supply. We also need to look seriously at strategies to reduce demand by changing our culture of steel use and improving our material efficiency. We must also pursue upcycling to produce high grade steel from scrap steel.
This will require cooperation from those who use steel as well as those who produce it. Steel products could be made more resource efficient if they are designed to last longer or be lightweight. When steel products reach the end of their life, upcycling could be achieved through advanced sorting and shredding to remove impurities from scrap steel. As a society, Japan may need to become less dependent on steel and shift to a ‘service use’ model rather than product ownership. Unlike today, when steel is abundant and cheap, a net-zero future will require us to use scarcer and more expensive steel resources with greater efficiency.
Dr Watari concludes that we need to invest in technological innovations, but we cannot just wait for them to appear. Instead, steel users must prepare for a world in which less steel is available: “We do not reject the need to invest in innovative production technologies. Rather, what we want to pay attention to is point is that we should instead look for much more strategic options. By simply relying on silver bullet production technologies. Placing material efficiency and upcycling at the heart of decarbonisation plans can reduce over-reliance on production technologies. reduce innovation and prepare for the risk that these technologies will not scale up enough in time.”