MONDAY’S STUDY: Who Buys Rooftop Solar?

Income Trends among U.S. Residential Rooftop Solar Adopters

Galen Barbose, Sydney Forrester, Naïm Darghouth, and Ben Hoen, February 2020 (Lawrence Berkeley National Laboratory)

Overview

A new Berkeley Lab annual report dedicated to describing income and other demographic trends of residential solar adopters

• Pairs Berkeley Lab’s Tracking the Sun dataset and other sources of PV addresses with householdlevel income data

• Focuses on residential rooftop solar photovoltaic (PV) systems, with an emphasis on 2018 installations

• This edition focuses primarily on income, though later editions may include trends related to other demographic attributes

• Analysis is descriptive in nature: intended to track basic trends and to serve as a foundational resource for further analyses and support for market participants

• Report is published in slide deck form with accompanying online data visualizations that allow users to further explore the data (see solardemographics.lbl.gov)

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Key Findings

Income distribution of 2018 residential solar adopters:

•15% have household incomes

• 50% of 2018 solar adopters are below the corresponding OO-HH median income

• Low-to-moderate income households: 6% of 2018 solar adopters have incomes…

Solar-Adopter Household Income Distributions

• Solar adopters span all income ranges

• Distribution peaks between $50-100k, but has a long upper tail

• Among 2018 solar adopters:  15% have household (HH) incomes

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Income Distribution of Solar Adopters vs. U.S. Population

• Comparing to Census data requires that we consolidate the income bins, as shown here

• Solar-adopter incomes skew high relative to all U.S. households  Income disparities are most pronounced at the low and high ends  Whereas HHs with incomes in the $50-100k range are proportionately represented

• Skew is less pronounced if comparing to just owner-occupied households (OO-HHs)  Solar adoption occurs primarily among singlefamily owner-occupied homes (due to ownercontrol of rooftop, owner/tenant split incentive)  Illustrates how home-ownership can be a key driver for income disparities between solar adopters and the broader population…

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Solar-Adopter Income Trends over Time

• Solar adoption has been slowly migrating toward lower incomes (at least since 2010*)  Sample share of HHs with incomes…

Solar-Adopter Income Distributions Across States

• Solar-adopter income distributions vary across states, but in general, roughly:  30-40%* of 2018 solar adopters have HH incomes in the $50-100k range  10-20% have incomes ≥$200k  10-25% have incomes…

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Solar-Adopter Credit Scores over Time

• Credit scores are often a key determinant to a HH’s ability to obtain solar financing

• The share of adopters with lower credit scores has grown over time, based on block-level medians (see figure notes)

• That said, solar adopters generally have high credit scores  Almost 90% of 2018 solar adopters have either Prime or Super-Prime credit scores  This distribution can vary across states (see appendix slide 43); Louisiana has a particularly large share of low credit-score solar adopters

• Compared to the broader population, solar adopters credit scores skew high  Among 2018 solar adopters, 35% had credit scores below their respective state median…

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Conclusions

• Solar adopters span all income ranges, and include LMI households in all states

• Solar-adopter incomes skew high relative to the broader population, though less so when compared to just owner-occupied households, and less so when compared on a more localized basis

• Solar adopters also skew high in terms of other financial measures—namely, home value and credit score

• Income and other disparities between solar adopters and the broader population have been diminishing gradually over time, reflecting both a broadening and a deepening of U.S. solar markets

• The degree of disparity varies significantly across states and local markets, and some markets exhibit income parity between solar adopters and the broader population

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