New Publication Co-Authored by Sharon Harlan in Building and Environment

Sharon Harlan and fellow researchers recently published their article, “Social and behavioral determinants of indoor temperatures in air-conditioned homes,” in Building and Environment. Their research focused on 46 air-conditioned residences in Phoenix, Arizona, and found that indoor air temperature was not determined based on income, and therefore, those with less economic stability sacrifice more for comfort.

Read the abstract below:

In many cities, environmental justice communities (i.e., lower socioeconomic status and communities of color) experience a higher burden of heat stress because their neighborhoods have lower vegetation density and a larger footprint of impervious surfaces than wealthier, whiter neighborhoods. Virtually all studies related to heat, health, and social equity have measured only outdoor temperatures. Yet a significant portion of exposure for many people may not be associated with outdoor conditions, as people in the developed world spend, on average, 87% of their time indoors (69% in a residence). Research shows that indoor thermal environment plays a key role in individual heat exposure and heat-related discomfort, injury, and death. Our study examined summertime residential indoor temperatures of 46 homes that reported using central air conditioning (AC) in the hot, semi-arid city of Phoenix, and examined relationships between temperatures and household survey responses. In Phoenix, where temperatures are dangerously high for much of the year, the use of AC is essential for well-being and safety. We found that residents’ preferred temperatures (self-reported ideal and comfort temperatures) were the strongest predictors of how they set their thermostats while awake and asleep. Indoor temperature profiles were not strongly related to household income or perceived limitations on AC use, such as cost of electricity, repairs, and environmental or medical concerns. The Residential Energy Consumption Survey (RECS) issued by the U.S. Energy Information Administration found that 20% of U.S. households reduce or go without food and medicine in order to pay energy bills. Households in our sample that reported difficulty with affording essentials still used AC to cool their homes in the summer. We believe they may have made similar tradeoffs. Health and energy policymakers should consider that lower-income households are likely burdened by heat, even if they are able to keep their indoor temperatures livable.

This work was supported by the National Science Foundation Hazards SEES (Science, Engineering and Education for Sustainability) grant number 1520803.

Wright, M.K., D.M. Hondula, P.M. Chakalian, L.C. Kurtz, L. Watkins, C.J. Gronlund, L. Larsen, E. Mallen, S.L. Harlan (2020) “Social and behavioral determinants of indoor temperatures in air-conditioned homes,” Building and Environment (180): 107187.

Photo credit: Drew Hays