Fig. 1.

Effects of informational messages on study households (n = 490,994 hourly kWh observations, 118 apartments by random assignment into treatment and control groups). Mean treatment effects are reported versus control households before and after treatment following a 6-mo baseline monitoring period. The cost savings information group shows no significant conservation behavior after the 100-d treatment period. The health group shows significant conservation behavior of 8.2% energy savings (significant at **P < 0.05) after the 100-d experimental period. Health-related information treatments are particularly effective on families with children, achieving 19% energy savings relative to control (significant at **P < 0.05). All panel regression estimates include statistical controls for household characteristics (apartment size, apartment layout, and building floor), occupancy (number of persons living in the household), hourly weather controls (e.g., heating and cooling degree hours), time fixed effects, and environmentalist ideology (head of household reports being an active member of an environmental organization). Materials and methods are available in SI Appendix.