Título: HOW TO BEST PROMOTE DOMESTIC WATER SAVINGS: INSIGHTS FROM AN RCT TESTING SOCIAL NORMS AND INTRINSIC MOTIVATIONS
Sala: E22
Hora: 12:30
Resumen: Water scarcity is a significant concern in Spain where high agricultural water demands intensify the problem. This study presents the first Randomized Controlled Trial (RCT) in Spain investigating the impact of behavioral nudges on domestic water consumption. A pre-registered RCT was conducted with 5,451 households in a mid-size city, randomly assigned to one of three groups: a social norm treatment (T1), an intrinsic motivation treatment based on the challenge of consuming 100 litres per person per day (T2), or a control group. Households were also classified into sub-treatments. Overall, the interventions had no significant impact on water consumption. However, when analyzed by sub-treatments (compared to the overall control), high users decrease consumption (above-average users in T1 and consumers not achieving the challenge in T2) and low users increase consumption (boomerang effect) (efficient users in T1 and achieving challenge in T2). When the sub-treatments are compared with the same stratified cohort in the control, there are no significant effects (only for household size 1 is observed a boomerang effect in T1 and T2). These findings suggest that the observed heterogeneous responses are likely driven by regression to the mean rather than by the behavioral interventions themselves, providing limited evidence in this study of the effectiveness of these nudges in reducing domestic water consumption.