UC Davis

Ratepayer-funded programs spend millions of dollars on home energy retrofits each year in the United States. Measuring the impacts of such retrofits is critically important to determining whether the benefits justify the costs, and if the program should be expanded, shuttered, or adjusted. Current efforts to measure the impacts of energy retrofits - when carried out at all - are typically limited in their scope. Most focus on energy benefits alone, and in particular, the monetary value of energy savings. While some take a broader perspective, inclusive of non-energy impacts (NEIs), many of those efforts focus exclusively on positive impacts and neglect the potential for negative ones. This research describes the limitations of common methods used to evaluate occupant NEIs of energy retrofit projects and introduces a framework for better understanding and evaluating occupants’ NEIs. We reviewed evaluation studies that measured occupant NEIs associated with energy retrofit projects. Based on this review, we developed a comprehensive typology of NEIs. We triangulated our NEI typology with an inventory of building retrofit measures from the National Residential Efficiency Measures Database to articulate the possible NEIs of specific retrofit measures, providing a framework to guide NEI assessments. The framework is a valuable resource because it can guide the assessment of NEIs generally as well as measure-specific NEIs, while capturing both positive and negative impacts. We also consider how our framework can be the foundation of a new assessment tool that addresses the limitations of common NEI evaluation methods.