<p>Residential energy conservation is a crucial yet often underutilized method for mitigating climate change. However, widespread estimation bias of household energy use and savings hinder practical behavioral intervention efforts. Through a national survey in China, here we reveal that residents systematically overestimate household energy use and savings, overvaluing low-energy activities while undervaluing high-energy ones. To bridge this cognitive gap, we conducted a randomized controlled experiment comparing three scalable intervention approaches: (1) providing numerical data on the energy consumption of household appliances and the savings from energy-conserving behaviors, (2) offering rank ordering information on these metrics, and (3) combining both types of information. All three succeeded in benefiting residents’ judgments about energy-conserving behaviors. Notably, only the rank ordering information led to actual behavioral changes in energy conservation. These findings underscore the transformative potential of well-designed interventions in fostering sustainable energy practices, offering actionable insights for climate policy and behavioral science.</p>