Electricity generation from small-scale solar energy systems in the United States, each with a capacity of less than 1 megawatt, increased from 18,812 gigawatt-hours to 92,979 gigawatt-hours over the past decade, according to estimates from the U.S. Energy Information Administration (EIA).
This figure includes small-scale or rooftop solar systems. California, Arizona, Texas, and Florida ranked as the leading states by generation, benefiting either from abundant solar resources or from rapid growth in installed capacity. New York, which is located in an area with less solar exposure, ranked fifth thanks to capacity growth, improving technologies, and government incentives.
California Leads
In 2025, California accounted for 37% of total small-scale solar generation in the United States, equivalent to 34,411 gigawatt-hours. Its generation increased by 8% between 2024 and 2025, alongside an increase in installed capacity from 18 to 20 gigawatts.
Part of the earlier surge was linked to the NEM 2.0 net energy metering program, which remained available until April 2023 and provided higher compensation for electricity exported to the grid than the subsequent NEM 3.0 net billing tariff. All capacity built under the previous program was also grandfathered in, encouraging an acceleration of installations before its expiration.
Uneven Growth Among States
Arizona ranked second, with generation reaching 5,795 gigawatt-hours, or more than 6% of the U.S. total. Its generation increased by 6% in 2025, while it recorded its largest increase, of 22%, between 2022 and 2023. The state offers an income tax credit equal to 25%, along with other incentives for installing solar panels.
In Texas, generation increased from 391 gigawatt-hours in 2016 to 5,408 gigawatt-hours in 2025. In Florida, it grew from 205 to 5,198 gigawatt-hours over the same period. Both states use property-tax exemptions and other incentive programs, some of which are linked to electric utilities.
What Is Changing in Practice?
The data show that the expansion of distributed solar does not depend exclusively on the intensity of solar radiation. Local policies, such as compensation for electricity returned to the grid and tax exemptions, can drive capacity growth even in states that are less climatically suitable. However, the annual growth rate has begun to decline since its 2022 peak, when generation increased 25% year over year amid record capacity growth.
The figures remain estimates, because utilities do not necessarily know how much energy rooftop systems generate on distribution networks. EIA therefore relies on utility data on the number of customers and total capacity, along with models such as the System Advisor Model and PVWatts from the National Renewable Energy Laboratory. It also uses assumptions about panel angles and orientations in California to represent other states, which constitutes a methodological limitation that should be taken into account when comparing the results.