At first glance, aluminum would appear to be in pole position when it comes to reducing carbon footprint. Because its low density makes it ideal for building lightweight and therefore fuel-efficient components. But there is more to the carbon footprint of a structural material than how it performs in use. We also need to look at the full story of both production and usage. That means considering the carbon emissions associated with its refining and processing.
This is where aluminum faces a challenge, since its mining and refining operations are very energy-intensive, resulting in a high carbon footprint. So, is there perhaps a case for stainless steel? Its high strength enables lightweight design. Furthermore, it has an inherently low carbon footprint since its production is based mainly on recycled scrap.
It was to settle this question that Outokumpu has collaborated with FKA, the Aachen-based research partner for the automotive industry, on a first-of-its-kind study. The aim was to evaluate the carbon footprint of a real-world component during both production and use.
The study looked at the performance of a battery case in a typical passenger electric vehicle over a projected life of 160,000 km when manufactured from three different materials: aluminum, carbon steel and stainless steel.
The results may come as a surprise.
Download the full whitepaper describing the study.