Small-scale solar generation in the U.S. has quadrupled in a decade, EIA says

Small-scale solar generation in the United States rose from 18,812 gigawatt-hours to 92,979 gigawatt-hours over the last decade, the Energy Information Administration reported on Oct. 16. The agency’s own title for the analysis says the output has quadrupled, and the raw figures show the real multiple is somewhat larger than that.

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Small-scale here means systems under one megawatt, the rooftop arrays on homes, schools, warehouses and small businesses that feed the grid from the distribution side. They are counted separately from the utility-scale fields that dominate solar headlines, and the gap between the two measures is a large part of why the rooftop story is easy to miss.

How EIA measures systems under one megawatt

Utility-scale plants report their output directly, while rooftop systems mostly sit behind customer meters, so EIA builds its small-scale estimate from utility reporting on its annual Electric Power Industry Report. That is the survey behind the 2025 state totals in the agency’s October analysis, and it is the reason the numbers arrive with a lag of many months.

The decade comparison runs from 18,812 GWh to 92,979 GWh, an increase of 74,167 GWh. Divide the later figure by the earlier one and the multiple lands just under five. EIA’s wording, quadrupled, is the conservative description of that jump. For context on how the equipment base grew, the agency has separately documented U.S. solar capacity growth and the record capacity additions that pushed the total up in 2022.

Generation grew 25% in 2022 compared with 2021, in the middle of that record build. The growth rate has declined since then, a detail EIA flags because it changes how the decade should be read. The first half of the period was a surge; the second half is a maturing market adding output at a slower pace from a much bigger base. A market that grows 25% in a single year cannot sustain that rate for long once the total reaches tens of thousands of gigawatt-hours, so some deceleration was always likely.

California, Arizona, Texas and Florida lead the totals

EIA names four states with the highest small-scale solar generation: California, Arizona, Texas and Florida. California is far ahead. It produced 34,411 GWh in 2025, or 37% of the national small-scale total, and its generation grew 8% from 2024 to 2025 as capacity rose from 18 gigawatts to 20 gigawatts. Arizona followed with 5,795 GWh, a little over 6% of the U.S. total, after a 6% gain in 2025 and a 22% jump from 2022 to 2023, its largest single-year increase.

Texas and Florida tell a different story, one of rapid catch-up. Texas went from 391 GWh in 2016 to 5,408 GWh in 2025, and Florida climbed from 205 GWh to 5,198 GWh over the same stretch. Both states have abundant sunshine, and the decade-long climb in each reflects a base that started very small, which is why the percentage gains look so steep next to California’s. In 2016 the two states together produced less than a fifth of what Arizona alone generated in 2025. New York ranked fifth nationally, according to the agency.

The state differences also show how policy shapes the shape of the curve. California’s NEM 2.0 net metering program, which credited exports from rooftop systems, remained open to new customers through April 2023, and the California Public Utilities Commission’s NEM 2.0 evaluation documents how that program performed. Arizona, for its part, offers a 25% state income-tax credit for solar installations, which the agency notes as part of the Arizona picture.

What the slowing growth rate suggests

Lindsay Aramayo and Marc Harnish were the principal contributors to the EIA analysis, which presents the decline in growth as a fact about the data rather than a prediction. The report does not attribute the slowdown to a single cause, and it would be a stretch to read it as a retreat. Output in 2025 was still far higher than in any earlier year of the decade, and California alone added about two gigawatts of capacity in the final year measured.

Newer state rules matter to the next stretch. California has moved homeowners onto a successor structure, described on the commission’s customer generation page, and other states from New Jersey to Illinois and Massachusetts run their own incentive programs that EIA cites as part of the landscape. Those programs differ widely in how much they pay for exported power.

For readers trying to place their own roof in this picture, EIA’s overview of where solar is found explains how sunshine, latitude and panel orientation affect output. The main conclusion from the Oct. 16 analysis is simple: rooftop and small commercial solar now supplies nearly 93,000 GWh a year, concentrated in a handful of sunny or well-incentivized states, and growing more slowly than it did earlier in the decade.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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