As of December 2020, the states with the most small-scale solar photovoltaic (PV) capacity were California (10.6 gigawatts (GW)), New Jersey (1.9 GW), and Massachusetts (1.8 GW). Of the 4.5 GW of small-scale solar capacity added in the United States in 2020, California accounted for 31%, the largest share by far. Although Texas and Florida have less total small-scale solar capacity than states such as California or New Jersey, capacity has grown rapidly in these states in recent years. In 2020, Texas added 422 megawatts (MW) of small-scale solar, and Florida added 282 MW. State incentives, strong solar resources, and policy changes are largely driving these gains.

New Jersey, New York, and Massachusetts are among the leading states for small-scale solar capacity despite having less favorable solar resources. In these states, long-standing state policies such as renewable and clean energy standards and other incentives, some of which include specific provisions for solar, have encouraged small-scale solar capacity growth.

In 2020, small-scale solar capacity in Texas grew by 63%, increasing from 670 MW in 2019 to 1,093 MW. Texas does not require utility companies to purchase excess energy from residential solar panels. As such, net metering, which allows customers who generate their own electricity to sell excess electricity back to the grid, is not available to many homeowners in Texas. Although net metering is not widely available, some retail electricity companies in Texas offer a renewable buyback program in the form of bill credits. In addition, Texas offers a property tax exemption for the added home value from rooftop solar installations, encouraging small-scale solar growth in the state.

Removing restrictions on leased solar systems has encouraged small-scale solar growth in Florida. Until April 2018, the Florida Public Service Commission restricted electricity sales from leased solar systems. Without the restriction, electricity customers can lease solar systems with little or no upfront costs, making solar PV more widely financially feasible and resulting in immense growth in residential solar PV installations across the state. In 2020, small-scale solar capacity in Florida grew 57%, increasing from 492 MW in 2019 to 773 MW.

Although not in the top states for total small-scale solar capacity, Illinois added 309 MW of small-scale solar capacity in 2020, the third-highest number of additions that year. These additions doubled small-scale solar capacity in the state from 206 MW in 2019 to 515 MW in 2020.

The U.S. Energy Information Administration (EIA) began publishing generation and capacity estimates from small-scale solar installations by state and sector in the Electric Power Monthly in 2015. EIA’s small-scale solar category includes any installation that is connected to the grid and is less than 1 MW in size. EIA also collects utility-scale solar installations (1 MW or larger) in its Annual Electric Generator Report. Solar PV installations that are smaller than 1 MW but connected at a power plant with 1 MW of capacity or larger are also captured in the Annual Electric Generator Report.