Co-benefits of energy efficiency in residential buildings.

Local and state governments find it challenging to adopt aggressive residential building codes that require energy-efficiency upgrades beyond those with a reasonable payback. Thus, economic considerations inhibit the progress towards a more energy-efficient housing stock and often account for direct utility savings. A widely discussed solution is to look beyond energy costs and consider other impacts of energy-saving strategies that affect their financial attractiveness. In this paper, we examine the case of a public housing project in Phoenix, AZ, using several tools to calculate different economic, environmental, and health metrics associated with the three levels of energy efficiency. Our results show that while the payback calculated from direct energy costs may not be attractive, we should consider other savings. We demonstrate that avoided health and climate costs could total around 40% of the direct utility savings. In addition, we quantify how energy-saving strategies can cool the neighborhood, make buildings more resilient to heat, improve indoor air quality, and reduce the transmission of airborne disease. These benefits could be translated to avoid costs in the future. • We demonstrate looking beyond utility cost in assessing building energy efficiency. • Avoided health/climate costs are in the order of magnitude of direct utility savings. • We show that building efficiency can increase the hours comfortable for window use. • Thus reducing the risk of indoor airborne disease transmission per Wells-Riley method. • Efficiency reduces indoor & outdoor (shown via an urban canyon model) heat exposure. [ABSTRACT FROM AUTHOR]