New Berkeley Lab report on solar-adopter income and demographic trends

March 2, 2022

Lawrence Berkeley National Laboratory has released the latest edition of its annual report, Residential Solar-Adopter Income and Demographic Trends. The report, based on address-level data for 2.3 million residential solar adopters across the country, describes trends in solar-adopter household income levels, race and ethnicity, language preference, rural vs. urban, education levels, occupation types, age, home value, and credit scores. The report also describes income differences across system ownership models, installers, system sizes, both stand-alone and paired solar-plus-storage systems, and systems on multi- vs. single-family buildings. This latest update includes data on systems installed through 2020.

The report is accompanied by an online data visualization tool that enables users to further explore the data from the report. The authors will also host a webinar highlighting key findings from this study on March 17th at 12:00 pm Pacific / 3:00 pm Eastern. Register for the webinar here.

Key findings from the study include the following:

Solar adopters span all income ranges, but generally skew high. Solar adopters are not a monolithic group and include both affluent and more moderate-income households (see Figure 1, left). In 2020, 41% of adopters had incomes below 120% of their respective Area Median Income (AMI), a threshold sometimes used to define Low and Moderate Income (LMI) households. Nevertheless, as a whole, solar-adopter incomes tend to be higher than those of the general population. Nationally, solar adopters’ median household income was $115,000 in 2020, compared to the U.S. median of $63,000. That disparity is partly related to home ownership, and also to the fact that roughly half of residential solar adopters were in California, a relatively high-income state. But even when controlling for those factors, solar adopter incomes still tend to skew high. For example, solar-adopter incomes were 58% higher than the median income of all households in the same county, or 23% higher if comparing only to owner-occupied households (OO-HHs) (Figure 1, right).

Figure 1. Solar-adopter income distribution in 2020 (left) and comparison to general population (right). The figure on the right is constructed by comparing each solar-adopter’s income to the median income for their respective state, county, tract, and block-group, and then taking the median of the resulting percentage value across all adopters. For block-groups, median incomes are available for all households only.

The disparity between solar-adopter incomes and the general population has been slowly narrowing over time. Between 2010 and 2020, U.S. median solar-adopter incomes fell on an absolute basis from $138k to $115k (see Figure 2, left). The drop reflects a “deepening” of solar markets, as adoption increases among less affluent households in each market, as indicated by the decline in solar adopters’ relative incomes, from 180% to 158% of their respective county-median incomes. In addition, solar markets are “broadening” into progressively less affluent states, as evident in the figure on the right, which shows an increasing share of the market moving into low- and middle-income states, since 2016. 

Figure 2. Temporal trend in solar-adopter median incomes (left) and distribution of solar adopters across states (right). For the figure on the left, solar adopter incomes are based on the year 2021, regardless of when PV installation occurred, without any inflation adjustment. For the figure on the right, states are grouped based on whether they fall into the lower, middle, or upper third of all states, in terms of median income of all households.

Solar adopters differ from the broader U.S. population in terms of a variety of other demographic and socioeconomic measures. Compared to the general population, solar adopters also tend to prefer English as their primary language, be middle-aged, identify as non-Hispanic White, have business or financial jobs, be more educated, have higher credit scores, and be more likely to live in rural areas (see Figure 3). Some of those comparisons—particularly those related to race, ethnicity, and language preference—show very different trends at the national versus state level. Those differences are largely the result of California’s dominant share of the U.S. residential solar market and the state’s particular demographic make-up.

Figure 3. Broader socio-economic differences between solar adopters and the general population. Note that the specific metrics differ across categories, and therefore are not directly comparable to one another.

For questions on the report, feel free to contact Galen Barbose at Lawrence Berkeley National Laboratory (510-495-2593, [email protected]).

We appreciate the funding support of the U.S. Department of Energy Solar Energy Technologies Office in making this work possible.