US rooftop solar output grew fivefold in a decade, with California accounting for 37% of national total
By Eve
Small scale solar installations under 1 megawatt in the United States generated 92,979 gigawatt hours in 2025, up from 18,812 gigawatt hours ten years earlier, according to the US Energy Information Administration's Annual Electric Power Industry Report cited by pv magazine USA. California led with 34,411 gigawatt hours, representing 37% of the national total, and saw its small scale solar capacity rise from 18 gigawatts to 20 gigawatts between 2024 and 2025. Nationwide growth peaked in 2022 at 25% year on year, partly driven by installations ahead of California's April 2023 shift from Net Energy Metering 2.0 to the Net Billing Tariff (NEM 3.0), which reduced export credits for new systems.
Why it matters
The surge in distributed solar capacity signals growing on site generation that can support EV charging infrastructure at homes and commercial sites, reducing grid demand and improving the business case for co located charging and solar projects. California's dominance and policy shifts under NEM 3.0 offer a template for other states considering tariff reforms that affect the economics of solar plus EV charging deployments.
Source
- Original title
- “US rooftop solar grew 5x in a decade, and California still generates 37% of it”
- Published
- 25 October 2026
- Updated
- 26 October 2026
In this story
- Topic
- Grid & Energy
- Places
- United States · California
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