Most of the utility-scale solar photovoltaic (PV) electric generating capacity has been installed in the southwestern part of the country in states such as California and Arizona, which together accounted for 64% of the national total as of September 2015. The South Atlantic region currently has about 11% of the nation’s 9,968 megawatts (MW) of utility-scale PV capacity, largely in North Carolina. Until now, Georgia has installed relatively little solar PV capacity, but the state plans to add more than 600 MW of utility-scale solar by the end of 2016.
Unlike the distributed generation often installed on rooftops, the utility-scale systems discussed here each have a generating capacity of one MW or greater. In 2014, North Carolina was second only to California in terms of utility-scale PV additions. Based on reported and planned installations for 2015, North Carolina will likely remain in second place. The top five states in terms of expected utility-scale PV additions in 2015—California, North Carolina, Nevada, Georgia, and Utah—account for more than 80% of the nearly 3,000 MW of utility-scale solar PV expected to be added in the United States during 2015.
Although they are at similar latitudes, the states in the Southern Atlantic region have lower-quality solar resources than areas in Southern California, Arizona, Nevada, and New Mexico, which have some of the best solar resources in the world. In addition to latitude, solar resource quality depends on levels of direct sunlight and diffuse sunlight, both being affected by cloud cover, humidity, and trace gases.