Table 1. Justification for the choice and prioritization of intervention groups.

No	Condition	Priority	Justification
1	Control 1	High	This control condition mimics the measurement regime of the intervention conditions, but does not provide any additional input to the participants.
2	Control 2	High	As the weekly reading of the electricity meters might be an intervention in itself, we also implemented a control condition with only two measurements at the start and end of the whole five-week period. The five week consumption was then evenly distributed across the five weeks to calculate the average consumption for the analyses.
3	Information	High	Information about what to do is considered essential for changing Behavior. Therefore, information with electricity saving tips was presented in all intervention conditions. This condition tests the effect of information only.
4	Information + social norms	High	The main aim of this intervention group is to single out the effect that social norm communication can have on top of “just” providing information.
5	Information + collective framing	High	This is the collective version of the information only condition, testing if a collective framing of information given is changing the results.
6	Information + collective framing + social norm	Low	This is the collectively framed version of condition 4, which tests if the framing changes the effects of social norms.
7	Information + commitment	High	This condition tests if being asked for (and giving) commitment changes the effect of information given.
8	Information + feedback	Low	This condition tests if individual feedback on changes in electricity consumption changes the effect of information given.
9	Information + collective framing + feedback	Low	This is the collectively framed version of condition 8, which tests if the framing changes the effects of feedback.
10	Information + competition + feedback	High	This condition tests if a competitive element (and accepting this) changes the effect of information given and feedback without a competition. As a competition always requires giving feedback, there is no condition testing competition without feedback.
11	Information + collective framing + competition + feedback	Low	This is the collectively framed version of condition 10 which tests if the framing changes the effects of competition combined with feedback.
12	Information + commitment + social norm	Low	As social norms and commitment deal with the individual and social components of moral decision making, we also included a condition combining these two interventions (in addition to information as a basis).
13	Information + competition + feedback + commitment + social norm	High	This is the individually framed version of the whole intervention package. We assume that the combination of interventions is more effective than single interventions.
14	Information + competition + feedback + commitment + social norm + collective framing	High	This is the collectively framed version of the whole intervention package. We assume that the combination of interventions is more effective than single interventions.