Residential Rooftop Solar Equity in Washington State

Abstract

Residential rooftop solar has not been deployed equitably in Washington State. This is consistent with various national studies that found socioeconomic barriers to solar access related to income, race, etc. This work focuses specifically on analyzing solar disparities in Washington state. A study by Tony G. Reames found significant differences in the socioeconomic factors influencing solar adoption in four US cities. For this reason, analyzing Washington state specifically can provide the Washington Department of Commerce with better insight into existing solar disparities. I model the relationship between solar per capita and socioeconomic factors in each census tract using a zero-inflated Poisson regression model. The model shows that socioeconomic disparities in Washington differ across the state as well as from national findings. Having a college education has the strongest positive correlation with the amount of solar per capita out of all socioeconomic factors considered. My model also confirms inequities in household income and race, similar to national findings.