The U.S residential June Solar Index, which covers residential and small commercial solar markets, included the following highlights:

• The US. Solar Index declined 10 percent in June and 14 percent in the year to date period compared to 2016
• The decline in California is slowing and growth in new markets (FL, SC, PA, UT, TX, etc.) has partially offset declines in mature markets (CA, NM, MA, etc.)

Analysis of the market performance through June indicates that 2017 may end up lower than industry analysts forecasts of -2.4 percent. Although the market is expected to decline in 2017, analysts predict a rebound in 2018 by 20 percent as mature markets "re-tool" and growth states attract early adopters.

The decline in select mature markets is likely due to the exhaustion of rebates in certain states as well a pull-back in acquisition spend by national installers. At the same time, solar companies are expanding into growth markets including Florida, South Carolina, and Nevada (after net metering decision reversal).

• In June, Sunrun announced that the company had expanded into seven more states (New Mexico, Rhode Island, Texas, Vermont, Wisconsin, Pennsylvania, Washington, D.C., Nevada and Florida), which nearly doubled the company's total addressable market to 28 million.
• In July, Vivint announced that the company was launching in Pittsburgh, Pennsylvania, after having expanded into New Hampshire, Florida, Rhode Island, Colorado, Nevada, Vermont, and Virginia in 2017.

Mature markets may receive a boost from battery storage, as California recently announced an expansion of residential solar incentives. Increased EV adoption could also convert PV adopters in mature markets.

California Index

• The California Solar Index, which represents approximately 40 percent of the market declined 30 percent in June and 34 percent in the year to date period compared to 2016.
• Year to date growth by city in California (links to data): San Diego (-39 percent), San Jose (-30 percent), Sacramento (0.3 percent), Riverside (-16 percent), and Los Angeles (-30 percent).

 
Solar Index Data Reference

The Solar Index analyzes solar permit data on a monthly basis for geographies in which the data is readily available. The Solar Index currently covers most major solar markets spanning 17 states and over 40 cities. The states included in the Solar Index represent more than 85 percent of the total market.