Assessing residential energy efficiency retrofit adoption potential and societal impacts across the US

<p dir="ltr">Residential and commercial buildings account for 75% of electricity and 40% of national energy consumption, contributing significantly to energy-related emissions. Historical discriminatory policies, particularly federal redlining, created prolonged disinvestment in infrastructure and generational wealth disparities. Today, these communities—75% low-to-moderate-income (LMI) and 64% neighborhoods of color—disproportionately face energy and environmental burdens. This research establishes a framework for equitable electrification, bridging historical injustice with clean energy transition opportunities. This dissertation addresses three primary research questions through the development and application of the Tradeoff Analysis of Residential retrofits for Energy equity (TARE) model. </p><p dir="ltr">First, I assess the lifetime climate impacts of existing residential housing and evaluate the cost-effectiveness of residential energy efficiency retrofits as a greenhouse gas mitigation strategy. Using various cost databases with regional cost adjustments and Inflation Reduction Act (IRA) rebate guidelines, heat pump water heaters emerged as the most cost-effective retrofit for greenhouse gas emissions abatement. </p><p dir="ltr">Second, I investigate how the IRA rebates and grid decarbonization affect equitable adoption of residential electrification technologies. I determine the economic feasibility or "adoption potential" of these retrofits through lifetime operational savings and emissions reductions under various policy scenarios. Results show that IRA rebates substantially improve adoption potential for LMI households relative to pre-IRA conditions, with adoption potential more than doubling for air-source heat pumps, heat pump water heaters, and electric cooking ranges, and more than tripling for heat pump clothes dryers. </p><p dir="ltr">Third, I assess adoption potential, incorporating lifecycle costs and monetized benefits from avoided climate and health-related emissions. Climate impacts were evaluated using three social cost of carbon estimates, while health benefits were quantified using six methodologies combining reduced-complexity models (InMAP, EASIUR, AP2) with various concentration?response functions. Heat pump water heaters emerge as optimal policy entry points, with LMI adoption potential reaching 96-99% for delivered fuel users. For air-source heat pump retrofits in LMI households, adoption potential ranges from below 2% for existing natural gas heating systems to 67% for fuel oil systems. Accounting for societal benefits from reduced greenhouse gas emissions increases economically viable retrofits from 16% (private costs only) to 53-67% (including climate benefits). Electrifying space heating in 85-96% of households would beneficially reduce criteria air pollutants, with health benefits accruing primarily through reduced public air pollution exposure. </p><p dir="ltr">My research demonstrates that decision-makers should prioritize heat pump water heaters as universal electrification entry points and design fuel-specific programs for space heating (with electric resistance and delivered fuels generally being the most effective retrofit opportunities. Future work can improve model flexibility for additional user inputs and expand to include Climate and Economic Justice Screening Tool thresholds for community-level analyses, ultimately expediting technical assistance for historically disadvantaged populations</p>