Grid-connected solar photovoltaic (PV) installations in the United States grew on average 71 percent annually from 2000-2008, totaling 1,102 megawatts (MW) by the end of 2008. However, the highly concentrated U.S. PV market is dominated by only a handful of states with strong incentives: the top six states in terms of installed MW host 90 percent of total capacity. Nonresidential PV installations (i.e. on commercial and public buildings) are even more concentrated, with over 90 percent in just five states.

This map was created by the National Renewable Energy Laboratory (NREL) for the Department of Energy. Installation data also from NREL: Doris et al., 2009.