Practitioners attribute to lack of methodology not including rebound effects in life cycle assessment

In a recent publication in the International Journal of Life Cycle Assessment, a group of WASTEWISE researchers, led by partners from the Swedish University of Agricultural Sciences (SLU), examines how Life Cycle Assessment (LCA) practitioners understand, consider, and address rebound effects in food-system assessments.

This study is based on a survey conducted with 79 food-system LCA practitioners, which combined quantitative questions on familiarity, perceived importance, and current practice with open-ended questions capturing motivations, barriers, and reasoning.

Analysis of the responses received revealed interesting information regarding practitioners’ perceptions of the rebound effect and the extent to which this aspect is incorporated into the life cycle assessment. For instance, they saw that awareness does not necessarily translate into practice. “Our survey of found that rebound effects are generally recognised as relevant but rarely included in quantitative assessments”, stated the first author of the paper Niina Sundin, from SLU.

The barriers that prevent the rebound effects from being included in the assessments are quite complex: even when relevant data exist, they may be too aggregated, outdated, context-specific or difficult to integrate into LCA models. Practitioners also reported a lack of methodological guidance and interdisciplinary expertise.

Indeed, established methodological conventions influence what gets included in LCAs. “One of our most interesting findings was that uncertainty does not appear to be treated consistently. Assumptions about avoided production are routinely applied in assessments despite considerable uncertainty, whereas uncertainty is frequently used to justify excluding rebound effects”, details the researcher.

Therefore, researchers consider the inclusion of rebound effects challenging, not necessarily because practitioners are unwilling to consider them, but rather because existing tools, methodological conventions and limited opportunities for interdisciplinary collaboration make their inclusion challenging in practice.