Untying the knot of behavioural rebound, negative spillover, and crowding-out mechanisms in environmental sustainability research: a systematic literature review

A comprehensive understanding of the mechanisms underlying rebound effects is crucial for explaining the observed offset in environmental gains. Nevertheless, research on behavioural rebound mechanisms remains scarce and is characterised by inconsistent terminology. The terms "behavioural rebound", "negative spillover", and "crowding-out" are used interchangeably, yet understanding of their differences and similarities remains lacking. To address this gap, a systematic literature review has been conducted, identifying 29 behavioural rebound, 30 negative spillover, and 20 crowding-out mechanisms, derived from 52 articles. The results highlight that the mechanisms differ on a structural (e.g., causal elements) and contextual level (e.g., analysed applications) in terms of input (e.g., presence of external intervention and intervention characteristics), output (e.g., identified endpoint and domain) and overall mechanism characteristics (e.g., number of behavioural changes and described effect type). This indicates that although behavioural rebound, negative spillover, and crowding-out mechanisms describe overlapping phenomena, the concepts should not be used as synonyms. Alternatively, negative spillover mechanisms can be considered as a type of behavioural rebound mechanisms. Furthermore, the results imply that crowding-out mechanisms could lead to negative spillover mechanisms, which in turn could lead to behavioural rebound mechanisms. This study concludes with recommendations for future research to improve interpretation as well as integration of the different concepts, supporting research on the often neglected but highly relevant behavioural mechanisms underlying rebound effects.