Abstract
Product life cycle engineering studies typically rely on average use-phase parameter values to estimate impact, such as average usage intensity, and operational efficiency. In reality, these parameters can vary temporally, and depend on user behaviour as well as the context in which the product is being used. Insights on these are especially important for durable goods with long service lives. In this study, we examine the variation in user experiences in an automotive Life Cycle Assessment (LCA) case study, which is found to have a substantial influence on the life-cycle impact results. This underscores the importance of considering uncertainty in LCA studies.