According to the study, immediate feedback via a smart shower head reduces water and energy consumption by an average of around 29 percent. Information about the consumption of one’s own household compared to other households can also encourage people to save water when showering. On average, such comparative reports reduce consumption by about nine percent. For the study, data from a field experiment with 570 households were analysed.
The most important facts in brief:
- Behavioural economic interventions, sometimes also called nudges, can significantly reduce water consumption when showering and the associated energy consumption. This is the conclusion of a recent study conducted by RWI and the University of Bonn in research partnership with the Center for Advanced Internet Studies (CAIS).
- In the field experiment, 570 households were randomly divided into four groups. The first group received so-called real-time feedback on their water consumption while showering by means of a smart shower head. Specifically, the shower head changes colours depending on the amount of water consumed, giving an indication of how many litres have already been used. The second group received regular reports on their water consumption compared to other households. In a third group, both measures were combined. The fourth group received no intervention as a control group.
- The results show that real-time feedback via smart shower heads leads to a reduction in average water consumption per shower of about 29 percent. Comparison reports reduce the average water consumption per shower by about 9 percent. The effect of combining both measures is 35 percent.
- The interviews during the study also show that the behavioural economic interventions were perceived as enrichment by most participants. Thus, most participants in the study would have been willing to pay an average of about 10 euros per month for the ongoing receipt of the interventions. The willingness to pay for real-time feedback was slightly higher than for the comparison reports.
- The field experiment took place between October 2020 and June 2021 in the Ruhr region and was funded by the Ministry of Culture and Science of the State of North Rhine-Westphalia and the German Research Foundation (DFG).
“Our study shows that the use of behavioural economic interventions can be an opportunity for the sustainable use of scarce resources. Useful behavioural economic interventions also seem to be valued by consumers in our field study,” says Mark Andor, head of RWI’s Prosocial Behaviour Research Group. “If they are used correctly, behavioural economic interventions can thus achieve a positive environmental and climate protection effect and still be perceived as enrichment. Further research could show whether the savings effects are limited to private households or can also be achieved in a similar form in public buildings such as hospitals, sports facilities or hotels.”