Unveiling the power of social norms interventions: Investigating energy savings behavior in an Italian energy cooperative

Behavioural strategies to reduce energy consumption and promote sustainable habits have received increasing attention from economic, psychological, and social sciences. Among these, social norm-based interventions have been proposed as effective tools in psychological research. In this study, we employ a randomized control trial (RCT) to assess the effectiveness of a social norms intervention to encourage energy-saving behaviors among members of an energy cooperative in Italy (N = 442). Anonymised electricity consumption data were collected over one year covering both pre- and post-intervention periods. The intervention lasted eight weeks and involved the dissemination of social norm messages via the cooperative's newsletter. In the RCT, participants were randomly assigned to one of three groups. The first group, the descriptive social norm group, received messages showing the average energy consumption of cooperative members to encourage behavioural change. The second group, the injunctive + descriptive social norm group, received messages combining average consumption data with additional messaging emphasising societal expectations for energy conservation. The third, which served as the control group, received no norm-based messaging and acted as a baseline for comparison. Our results show a significant 13 % decrease in electricity consumption among participants exposed to the descriptive social norm message, compared to those in the injunctive + descriptive norms and control groups. This behavioural change also emerged from the findings of a post-intervention self-report survey, indicating consistency between reported and observed behavior.