Session: LCA Methods

The Role of Displaced Production in Life Cycle Assessments
Roland Geyer,^*   Bren School of Environmental Science and Management, UCSB
Vered Doctori Blass,   Bren School of Environmental Science and Management, UCSB

Recycling of materials and reuse of products or their components is a critical part of life cycle management and product stewardship. Many life cycle management initiatives are driven by the idea of turning production and product wastes into secondary resources that avoid primary production processes. Life cycle assessments consistently show that the environmental benefits of displacing other production processes, like primary material production, are usually substantially larger than the benefits of avoiding landfill or incineration. In fact, the emerging standard for modeling product systems with reuse or recycling, the avoided burden approach, is based on the premise of displaced production. However, life cycle assessments of product systems with reuse and recycling all share one fundamental problem: How do we know that reuse and recycling activities displace other production processes, and how do we determine which processes are displaced and to what extent? This is not a trivial matter since any proof of displacement has to be based on counterfactual reasoning. An example of counterfactual logic is: ‘Virgin paper production would have been x tons higher if y tons of paper had not been recycled.’ This presentation gives an account of the existing practices in life cycle assessment with respect to displacement and reviews efforts to substantiate these practices with empirical evidence. It is surprising and troublesome how little empirical work exists to date, given the importance of reuse and recycling in life cycle assessments. The second part of the talk presents an empirical analysis framework of displacement and its application to several case studies.

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