This study leverages a large RCT to examine the potential of goal-setting nudges to encourage resource conservation at scale. We randomize a feature that allows subjects to set themselves energy consumption targets in a popular smartphone app. We document negative effects of the nudge on app utilization and estimate null effects on energy consumption with confidence intervals that rule out estimates from observational studies. A complementary survey identifies the mechanisms underlying these behavioral responses. Using a structural model and random variation of the app’s price, we estimate that the average user is willing to pay 7.41 EUR to avoid the nudge.