The Headline Number, and What It Actually Means
Total US solar installations came in at 7.8 GWdc in Q1 2026, down 27% year over year and down 42% quarter over quarter. That is the number that gets quoted. The number underneath it tells a more specific story: residential installs actually rose 6% year over year in the same quarter, to 1,179 MWdc, even as the overall market contracted hard.
Both numbers are true at once because they measure different things. The residential bump is a pull-forward effect: homeowners who wanted a system before the Section 25D federal tax credit expired rushed to close before January 1, 2026, so a chunk of 2026's early volume is really demand that got borrowed from later in the year. That is also why residential installs fell 15% quarter over quarter versus Q4 2025, the deadline rush working its way out of the pipeline.
Why the Full-Year Forecast Is Worse Than Q1 Looks
SEIA forecasts residential solar installations down 18% to 21% for the full year of 2026. The driver is the same one behind the Q1 pull-forward: the Section 25D residential tax credit ended on a hard cliff, with no phase-down, for any system installed on or after January 1, 2026, under the One Big Beautiful Bill Act signed July 4, 2025. Cash and loan buyers get zero federal credit on a system installed this year. The only path back to a 30 percent-equivalent credit is Section 48E, which is claimed by the system owner, which is why lease and power purchase agreement deals are absorbing so much of the market (see the NEM 3.0 and dealer-fee data below for how that plays out).
The Segments Still Moving the Other Direction
| Metric | Q1 2026 / 2025 Figure | Direction |
|---|---|---|
| Total US installs (Q1 2026) | 7.8 GWdc | Down 27% YoY, down 42% QoQ |
| Residential installs (Q1 2026) | 1,179 MWdc | Up 6% YoY, down 15% QoQ |
| Full-year residential forecast (2026) | Down 18% to 21% | Contraction |
| Commercial and industrial (2025 actual) | Up 6% (+2,345 MWdc) | 2026 forecast down 13% |
| Solar and storage attach rate (Q1 2026) | 45% | Up from 38% a year earlier |
| Residential battery storage (2025 total) | 3.1 GWh | Up 51% YoY |
Two segments are the exception to the contraction story. Battery storage grew 51% year over year in 2025, and the national solar-plus-storage attach rate hit 45% in Q1 2026, up from 38% a year earlier. Commercial and industrial solar also grew in 2025, though SEIA forecasts a 13% decline for 2026, driven largely by California's regulatory changes. If there is a genuine growth story left in this market, it is in storage, not in standalone residential rooftop solar.
Sources
The external data in this article draws on the sources below. Figures described in the text as estimates or industry triangulations are directional and are not attributed to a single dataset.
- SEIA, Q2 2026 Solar Market Insight Report
- SEIA, Q1 2026 installation data (via TaiyangNews)
- SEIA, clean energy provisions of the OBBBA
- SurgePV, 2026 US residential solar market trends