Reducing fume hood energy use in US undergraduate classes by leveraging interpersonal efficacy and extrinsic rewards

Abstract

PurposeGiven the potential of individual behavior change to address environmental issues, organizations such as universities have explored ways to significantly reduce energy use in workplaces and on campuses. With approximately 500,000 to 1,500,000 fume hoods operating in the U.S., and their corresponding aggregate electricity use of 26 TWh/year, one opportunity is to change fume hood use behaviors. We explored whether students improved their closing of fume hoods with interpersonal efficacy message, an extrinsic reward, or a combination of the two, potentially leading to energy, carbon, and financial savings. DesignWe randomly assigned chemistry classes to one of four experimental conditions: interpersonal efficacy, extrinsic reward, a combination of interpersonal efficacy and extrinsic reward, or control. Observational data and survey responses were collected before and after the intervention. Data were analyzed to assess the effect of conditions on fume hood use behavior accounting for pre-intervention responses. This study was approved by the Vanderbilt University Institutional Review Boardand all participants consented to participate in the study. FindingsResults showed that all interventions were effective at increasing observed closing of fume hoods compared to a control. Additionally, all interventions were largely effective at increasing self-reported closing of fume hoods and future intentions. The interpersonal efficacy intervention resulted in a faster rate of behavior change compared to all others. The extrinsic reward intervention increased reminders to fellow students about closing their fume hoods. Over the study period the interventions reduced energy use by 35%, carbon emissions by 36%, and operating costs by 35%. There was no evidence of positive or negative spillover on participants environmental behaviors outside the classroom. OriginalityThis study employed two types of novel low-cost interventions that can be easily scaled to larger populations. Additionally, our assessment examined behavioral spillover and direct environmental and financial impacts of the interventions.