Quantifying the circularity gap: Life Cycle Assessment (LCA) and Circularity Assessment (CA) as complementary methods for the circular redesign of complex products: A case study of industrial footwear

The sustainability and circularity assessment of multicompetent products is not straightforward. In order to provide guidance on the possibilities and limitations of the proven tools of Life Cycle Assessment (LCA) and Circularity Assessment (CA), this study uses the case of industrial footwear. Industrial Footwear has a complex global supply chain, with inputs from an extensive array of industries across the globe, such as agriculture, livestock, petrochemicals, manufacturing, logistics, and retail. Additionally, the high safety and quality standards contribute to increased product complexity and material diversity, yielding a product with more than ten components and seventy materials transported from a dozen countries.
With Europe’s Circular Economy Action Plan placing special emphasis on textiles and plastics (European Commission, 2015); tackling issues of product complexity, and dematerialization has become a priority within product redesign for circularity. However, product complexity offers an extended lifetime, and material diversity allows for safety and quality. This interplay requires an understanding of the role of multi-material/multicomponent products and the impacts that this has on sustainability and CE, especially when the material mix comes from both the biological and technical cycles.
The goal of this research is to: 1) understand the influence that circular product redesign has on the environmental performance of a multicomponent product through a comparative LCA and 2) Provide guidance on the possibilities and limitations of using CA and LCA as complementary tools for decision-making. For this, two case studies were used: 1) A business-as-usual and 2) circularity-designed industrial footwear. For both cases, the system boundaries included extraction, manufacturing, transport, recycling, and disposal. For each, an LCA and CA were performed using the ISO 14040:2006 standard (International Organization for Standardization, 2006), and the Circular Transition Indicators (World Business Council for Sustainable Development, 2022), respectively.
This research provides valuable insights into the role of material selection, product complexity, global transport, value retention, and end-of-life for improved environmental and circularity performance in industrial footwear. Of particular relevance is the use of leather and polyurethane for lifetime extension versus their environmental impacts, which suggests that circular practices can significantly influence value retention at the end-of-life, but not from the LCA perspective. Most importantly, the results of this research pave the way to develop a comprehensive methodology that integrates LCA and CA for redesigning products in a circular economy.
References:
European Commission. (2015). Circular Economy Action Plan. For a Cleaner and more competitive Europe.
International Organization for Standardization. (2006). ISO - ISO 14040:2006 - Environmental management — Life cycle assessment — Principles and framework. https://www.iso.org/standard/37456.html
World Business Council for Sustainable Development. (2022). Circular Transition Indicators V3.0.