Solar power in the United States


includes solar farms as well as local distributed generation, mostly on rooftops and increasingly from community solar arrays. In 2024, utility-scale solar power generated 219.8 terawatt-hours in the United States. Total solar generation that year, including estimated small-scale photovoltaic generation, was 303.8 TWh.
As of the end of 2024, the United States had 239 gigawatts of installed photovoltaic and concentrated solar power capacity combined. This capacity is exceeded only by China and the European Union. In 2024, 66% of all new electricity generation capacity in the U.S. came from solar.
The United States conducted much early research in photovoltaics and concentrated solar power. It is among the top countries in the world in electricity generated by the sun and several of the world's largest utility-scale installations are located in the desert Southwest. The oldest solar power plant in the world is the 354-megawatt Solar Energy Generating Systems thermal power plant in California. The Ivanpah Solar Electric Generating System is a solar thermal power project in the Mojave Desert, southwest of Las Vegas, with a gross capacity of 392 MW. The 280 MW Solana Generating Station is a solar power plant near Gila Bend, Arizona, about southwest of Phoenix, completed in 2013. When commissioned it was the largest parabolic trough plant in the world and the first U.S. solar plant with molten salt thermal energy storage. By 2015, solar employment had overtaken oil and gas as well as coal employment in the United States. As of 2023, more than 280,000 Americans were employed in the solar industry.
Many states have set individual renewable energy goals with solar power being included in various proportions. Hawaii plans 100% renewable-sourced electricity by 2045. Governor Jerry Brown signed legislation requiring California's utilities to obtain 100 percent of their electricity from zero-carbon sources by the end of 2045.

Solar potential

A 2012 report from the National Renewable Energy Laboratory described technically available renewable energy resources for each state and estimated that urban utility-scale photovoltaics could supply 2,232 TWh/year, rural utility-scale PV 280,613 TWh/year, rooftop PV 818 TWh/year, and CSP 116,146 TWh/year, for a total of almost 400,000 TWh/year, 100 times the consumption of 3,856 TWh in 2011.
For comparison, onshore wind potential is estimated at 32,784 TWh/year, and offshore wind at 16,976 TWh/year, while the total available from all renewable resources is estimated at 481,963 TWh/year.
Renewable energy is the least expensive source of power generation, even considering the upfront cost of installation. Therefore, the economics of the renewable energy transition are highly favorable unlike in prior decades. Solar is second only to onshore wind turbines in levelized cost of electricity competitiveness. Replacing historical sources of fossil energy with solar and wind results in lower operating costs for utility providers and lower energy costs for consumers. This does not include the significant additional health and mortality burden to society from fossil fuel use that makes it even more expensive than it appears.

History

The Carter administration provided major subsidies for research into photovoltaic technology and sought to increase commercialization in the industry.
In the early 1980s, the US accounted for more than 85% of the solar market.
During the Reagan administration, oil prices decreased and the US removed most of its policies that supported its solar industry. Government subsidies were higher in Germany and Japan, which prompted the industrial supply chain to begin moving from the US to those countries.
Solar energy deployment increased at a record pace in the United States and throughout the world in 2008, according to industry reports. The Solar Energy Industries Association's "2008 U.S. Solar Industry Year in Review" found that U.S. solar energy capacity increased by 17% in 2007, reaching the total equivalent of 8,775 megawatts. The SEIA report tallies all types of solar energy, and in 2007 the United States installed 342 MW of solar photovoltaic electric power, 139 thermal megawatts of solar water heating, 762 MWth of pool heating, and 21 MWth of solar space heating and cooling.
Another report in 2008 by research and publishing firm Clean Edge and the nonprofit Co-op America found that solar power's contribution could grow to 10% of the nation's power needs by 2025, with nearly 2% of the nation's electricity coming from concentrating solar power systems, while solar photovoltaic systems would provide more than 8% of the nation's electricity.
Those figures correlate to nearly 50,000 megawatts of solar photovoltaic systems and more than 6,600 megawatts of concentrating solar power.
The report noted that the cost per kilowatt-hour of solar photovoltaic systems had been dropping, while electricity generated from fossil fuels was becoming more expensive.
As a result, the report projects that solar power was expected to reach cost parity with conventional power sources in many U.S. markets by 2015.
To reach the 10% goal, solar photovoltaic companies would need to make solar power a "plug-and-play technology", or simplify the deployment of solar systems.
The report also underlines the importance of future "smart grid" technologies.
Solar Energy Industries Association and GTM Research found that the amount of new solar electric capacity increased in 2012 by 76 percent from 2011, raising the United States’ market share of the world's installations above 10 percent, up from roughly 5 to 7 percent in the past seven years.
According to the U.S. Energy Information Administration, as of September 2014 utility-scale solar had sent 12,303 gigawatt-hours of electricity to the U.S. grid. This was an increase of over 100% versus the same period in 2013.
The number of homes with solar systems installed had been increasing rapidly, from 30,000 in 2006 to 1.3 million in 2016. A 2014 study by the U.S. Department of Energy predicted the figure could reach 3.8 million homes by 2020.

Solar photovoltaic power

Solar PV installed capacity

In the United States, 14,626 MW of PV was installed in 2016, a 95% increase over 2015.
During 2016, 22 states added at least 100 MW of capacity.
Just 4,751 MW of PV installations were completed in 2013. The U.S. had approximately 440 MW of off-grid photovoltaics as of the end of 2010. Through the end of 2005, a majority of photovoltaics in the United States was off-grid.
In 2023 the total capacity deployed was 35.3 GW, which is 52% greater than the new capacity of just under 24 GW in 2022.

Solar PV generation

The amount of electricity a unit is capable of producing over an extended period of time is determined by multiplying the capacity by the capacity factor.
The capacity factor for solar photovoltaic units is largely a function of climate and latitude and so varies significantly from state to state.
The National Renewable Energy Laboratory has calculated that the highest statewide average solar voltaic capacity factors are in Arizona, New Mexico, and Nevada, and the lowest is Alaska. The lowest statewide average capacity factor in the contiguous 48 states is in West Virginia.

Solar power by type

The table above gives an indication of the spread of solar power between the different types at the end of 2021. Capacity figures may seem smaller than those quoted by other sources and it is likely that the capacities are measured in MW AC rather than MW DC, the former of which gives a lower reading due to conversion losses during the process by which power is transformed by inverters from direct current to alternating current.

Large-scale PV facilities

Large-scale photovoltaic power plants in the United States often consist of two or more units which correspond to construction stages and/or technology-improvement phases of a particular development project. Typically these units are co-located in the vicinity of the same high-capacity transmission substation, and may also feed that substation with other large PV plants which are adjacently sited but separately developed.
An objector at non-profit “Basin and Range Watch” to the Riverside East Solar Energy Zone in the California desert said in 2023 that "solar plants create myriad environmental problems, including habitat destruction and 'lethal death traps' for birds, which dive at the panels, mistaking them for water... one project bulldozed 600 acres of designated critical habitat for the endangered desert tortoise, while populations of Mojave fringe-toed lizards and bighorn sheep have also been afflicted." The same article included many other examples of how the same solar project had hurt the desert flora and fauna, according to environmentalists.
NameStateLocationCapacity
OwnerYearNotes
Copper Mountain Solar FacilityNevada802 Sempra Generation SolarFive phases
Gemini Solar ProjectNevada9662024690 MWAC, with 380 MW of batteries
Edwards Sanborn Solar and Energy Storage ProjectCalifornia86420233,320 MWh battery storage
Lumina I and II Solar ProjectTexas8282024640 MWac
Mount Signal SolarCalifornia7942020Phase 1 of 206 MWAC in May 2014. Phase 3 of 254 MWAC in July 2018. Phase 2 of 154 MWAC completed in January 2020. Total 614 MWAC
Solar star I & IICalifornia
7472015579 MWAC, was world's largest when completed.
Prospero Solar I and IITexas7102021550 MWAC
Westlands Solar ParkCalifornia672 2023Solar park, up to 2000 MWAC when completed
Frye Solar Power PlantTexas6372024500 MWac
Roseland SolarTexas6402023500 MWac
Atkina Solar Power PlantTexas6312024500 MWac
Spotsylvania Solar Energy ProjectVirginia6172021
Taygete SolarTexas6022023459 MWac, built in two phases - Taygete I of 255 MWac and Taygete II of 204 MWac
Desert Sunlight Solar FarmCalifornia550 2015Phase I of 300 MWAC completed 2013. Phase II to final capacity completed January 2015.
TopazCalifornia585.92014550 MWac
Mesquite Solar projectArizona513 2016Up to 700 MWAC when complete. Fifth phase completed in January 2024
Oberon Solar ProjectCalifornia5002023250 MW battery storage
Roadrunner Solar ProjectTexas4972019
Daggett SolarCalifornia4822023280 MW of energy storage
McCoy/Blythe Mesa Solar Power ProjectCalifornia485NextEra Energy
Mammoth SolarIndiana4802024First of three phases to total 1,600 MW.
Permian Energy CenterTexas460 2019
Red-Tailed HawkTexas4582024
Texas Solar NovaTexas4522024