This tracking report, published in slide-deck form, describes income trends among single-family residential solar adopters, and is intended to serve as a foundational reference document for policy-makers, industry stakeholders, and researchers. The analysis relies on a dataset unique in its size, geographic scope, and level of detail, pairing PV-system addresses for the vast majority of U.S. residential systems with household-level income estimates and other demographic data. This report focuses on systems installed through 2018, and includes data for roughly 1.4 million residential rooftop solar adopters across the country.
Key findings from this report include the following:
- Solar adopters span all income ranges, including low-to-moderate (LMI) households. Among 2018 residential solar adopters in the dataset, 15% have household incomes <$50k, 33% are between $50-100k, 24% are between $100-150k, and the remaining 28% are ≥$150k. Using one common definition of LMI, 15% of 2018 adopters are below 80% of their respective Area Median Income (AMI), while 30% are below 120% of AMI.
- Solar-adopter incomes skew high relative to the broader population, though less so when compared to just owner-occupied households (OO-HHs), and also less so when compared to other households in the same local area (e.g., county or census tract). For example, 18% of 2018 solar adopters have incomes below the national median for all households, while 30% are below the national median for OO-HHs, and 38% are below the median income for OO-HHs in the same census tract.
- The degree of disparity varies significantly across states and local markets. Among individual states, typically anywhere from 25-50% of 2018 solar adopters have incomes below the state median for all OO-HHs, and a similar range applies across most counties as well. A total of 3 states and 42 counties in the dataset exhibit “income parity”, where at least half of all 2018 solar adopters have incomes below the corresponding median for all OO-HHs.
- Solar adoption has been gradually migrating toward lower income ranges over time, reflecting both a broadening and a deepening of U.S. solar markets. For example, households with incomes <$100k grew from 39% of solar adopters in 2010 to 48% in 2018, while those with incomes ≥$200k dropped from 26% to 16%. Similar trends are evident within most individual states and counties as well.
- Solar adopters also skew high in terms of home value and credit score, relative to the broader population. Among all 2018 solar adopters, 27% have home values below their respective county median, while 35% have credit scores below the median. As with the income trends, however, these numbers have been rising over time as adoption rates increase among households with below-median home values and credit scores.
In conjunction with the report, Berkeley Lab has published an accompanying set of online data visualizations that allow users to further explore the underlying data. Berkeley Lab is also offering related analytical support to states, local agencies, and other organizations on issues related to solar adoption among low-to-moderate income households; requests for analytical support may be submitted through this online form.