California remains the undisputed champion, with 19.8 gigawatts of solar PV capacity, nearly five times as much as second-ranked North Carolina.
In fact, there was no change in the top five in 2017, but outside these slots there were plenty of movers and shakers.
Florida returned to the top 10 for the first time since 2011, as the Sunshine State added the third most new solar capacity last year. South Carolina saw the eighth biggest jump in capacity and climbed more rungs than any of the 44 markets tracked by the association.
Those moves reflect one of the report's key findings: Growth in solar PV capacity is spreading beyond the major markets to the Southeast and Midwest. Markets outside the top 10 accounted for 21 percent of total installed capacity last year, up from 16 percent in 2016.
Along with Florida and South Carolina, this trend is playing out in states such as Minnesota, Virginia, Alabama and Mississippi — all of which ranked in the top 20 for new solar capacity installations in 2017.
These and other emerging U.S. markets will play a big part in driving future solar PV growth, as the major state markets experience headwinds in the coming years.