The United States added 2,193 MW of solar PV capacity last year, with the state of California accounting for 75 percent of that figure, according to a new report by the U.S. Energy Information Administration (EIA).
The countrys solar sector continued the trend of strong growth, boosted in part by falling technology costs and aggressive state renewable portfolio standards (RPS) as well as continued federal investment tax credits.
Arizona followed California as the state with the most newly added PV capacity, making up 10 percent of the nations total last year, according to the report.
The EIAs figures did not include distributed capacity under 1 MW. Distributed solar PV capacity additions also grew in 2013, with industry reports estimating non-utility additions of 1.9 GW, most of which was likewise located in California.
The EIA also looked at the solar thermal industry, adding that after many years of little activity, the sector completed several large-scale solar thermal plants last year in Arizona and California totaling 766 MW of capacity, more than doubling the total solar thermal capacity in the United States.
While a few more projects are expected to be completed between 2014 and 2016, several other announced projects have since been cancelled or suspended due to a number of challenges, including environmental impacts on desert wildlife and water resources, cost-competitiveness and delays in transmission development.
In addition, the EIA said wind capacity additions, which reached 1,032 MW last year, dropped sharply to less than one-tenth of the capacity added in 2012 (12,885 MW). The report said the dramatic plunge had been expected as a result of the rush to complete wind projects in 2012 to qualify for the federal production tax credit. Unlike previous versions of the tax credit, the one-year extension for 2013 allowed developers to claim the tax credit for projects that began construction in 2013 even if the project will be completed in a later year. Consequently, developers were not as pressured to complete wind projects by the end of 2013. The tax credit has not been extended this year. More than 90 percent of the added wind generation capacity in 2013 was located in five states: California, Kansas, Michigan, Texas and New York.
In total, a little more than 13.5 GW of new capacity was added in 2013, less than half the capacity added in 2012. Solar provided nearly 22 percent of new utility-scale generating capacity added last year, a jump from less than 6 percent in 2012. Natural gas-fired power plants accounted for just over 50 percent, while coal provided 11 percent and wind nearly 8 percent. Almost half of all capacity added in 2013 was located in California.