Solar power in Nebraska is used for only a very small percentage of the state's electricity, although it is rapidly becoming competitive with grid electricity, due to the decrease in cost and the eight-year extension to the 30% tax credit, which can be used to install systems of any size. In 2015, the state ranked 47th among the 50 U.S. states with 1.1 MW of installed capacity.
As of the first quarter of 2023, Washington State has 604 MW of solar power electricity generation. This is an increase from about 300 MW in 2021 and 27 MW in 2013.
Solar power in South Carolina is rapidly becoming competitive with grid electricity, due to the decrease in cost and the eight-year extension to the 30% federal tax credit, which can be used to install any size system. South Carolina offers a 25% tax credit, meaning that 55% of the cost is covered through tax credits.
Solar power in Kentucky has been growing in recent years due to new technological improvements and a variety of regulatory actions and financial incentives, particularly a 30% federal tax credit, available through 2016, for any size project. Kentucky could generate 10% of all of the electricity used in the United States from land cleared from coal mining in the state. Covering just one-fifth with photovoltaics would supply all of the state's electricity.
Solar power in Ohio has been increasing, as the cost of photovoltaics has decreased. Ohio installed 10 MW of solar in 2015. Ohio adopted a net metering rule which allows any customer generating up to 25 kW to use net metering, with the kilowatt hour surplus rolled over each month, and paid by the utility once a year at the generation rate upon request. For hospitals there is no limit on size, but two meters are required, one for generation, the other for utility supplied power.
Solar power in Indiana has been growing in recent years due to new technological improvements and a variety of regulatory actions and financial incentives, particularly a 30% federal tax credit for any size project.
Solar power in Kansas has been growing in recent years due to new technological improvements and a variety of regulatory actions and financial incentives.
Solar power in West Virginia on rooftops can provide 23% of all electricity used in West Virginia from 6,300 MW of solar panels, but West Virginia will be the last state in the United States to reach grid parity - the point where solar panels are cheaper than grid electricity - without incentives, due to the low cost of electricity - about $0.062/kWh. The point where grid parity is reached is a product of the average insolation and the average cost of electricity. At $0.062/kWh and 4.3 sun-hours/day, solar panels would need to come down to ~$1,850/kW installed to achieve grid parity. The first state in the US to achieve grid parity was Hawaii. Solar power's favorable carbon footprint compared to fossil fuels is a major motivation for expanding renewable energy in the state, especially when compared to coal to generate electrical power.
Solar power in Iowa is limited but growing, with 137 megawatts (MW) installed by the end of 2019 and 27 MW installed during that year, ranking the state 40th among U.S. states. Iowa also generated 0.23% of the state's total electricity production in 2019 from solar energy; an amount sufficient to power over 17,000 Iowa homes. The state's early position as a major wind-power provider may have limited early large-scale solar investment.
Solar power in South Dakota has high potential but little practical application. The state ranked 50th among U.S. states in installed solar polar in 2015 with no utility-scale or large commercial systems. Photovoltaic panels on rooftops can provide 38.7% of all electricity used in South Dakota using 3,800 MW of solar panels. The state is ranked 14th in the country in solar power potential, and 4th in wind potential.
Mississippi has substantial potential for solar power, though it remains an underutilized generation method. The rate of installations has increased in recent years, reaching 438 MW of installed capacity in early 2023, ranking 36th among the states. Rooftop photovoltaics could provide 31.2% of all electricity used in Mississippi from 11,700 MW if solar panels were installed on every available roof.
Solar power in Maine on rooftops, utilizing 6,300 megawatts (MW) of solar panels, can provide 60% of the electricity used in Maine according to a 2016 U.S. Department of Energy study. Maine and Vermont are tied for the second highest rooftop solar potential in the country, only behind the state of California. A 2020 estimate suggests that a typical 5.6 kilowatt (kW) residential system will pay for itself in 6-7 years and generate a profit of $45,000 over the rest of its 25-year life from the tax credits and utility savings.
Solar power in Oklahoma can provide 44.1% of all electricity used in Oklahoma from 19,300 MW of rooftop solar panels. This scenario is extremely unlikely though because the cost of electricity in Oklahoma is among the lowest in the nation.
Solar power in Arkansas on rooftops can provide 33.3% of all electricity used in Arkansas from 12,200 MW of solar panels.
Solar power in Alabama on rooftops could theoretically provide 29.8% of all electricity used in Alabama, with 20,400 MW of solar panels potentially installed on rooftops.
Solar power in Illinois has been increasing, as the cost of photovoltaics has decreased. As of the end of 2020, Illinois had 465 megawatts (MW) of installed photovoltaic and concentrated solar power capacity combined employing over 5,200 jobs. Illinois adopted a net metering rule which allows customers generating up to 40 kW to use net metering, with the kilowatt hour surplus rolled over each month, and lost at the end of either April or October, as selected by the customer. In 2011, the limit was raised to 2 MW, but is not net metering, as the term is commonly known, as it uses two meters for systems larger than 40 kW.
Solar power in Minnesota expanded significantly in the early 2010s as a result of the cost decrease of photovoltaics and favorable policies. By 2016, it began to grow quickly.
Solar power in Montana on rooftops could provide 28% of all electricity used in Montana from 3,200 MW of solar panels.
Solar power in New Hampshire provides a small percentage of the state's electricity. State renewable requirements and declining prices have led to some installations. Photovoltaics on rooftops can provide 53.4% of all electricity used in New Hampshire, from 5,300 MW of solar panels, and 72% of the electricity used in Concord, New Hampshire. A 2016 estimate suggests that a typical 5 kW system costing $25,000 before credits and utility savings will pay for itself in 9 years, and generate a profit of $34,196 over the rest of its 25-year life. A loan or lease provides a net savings each year, including the first year. New Hampshire has a rebate program which pays $0.75/W for residential systems up to 5 kW, for up to 50% of the system cost, up to $3,750. However, New Hampshire's solar installation lagged behind nearby states such as Vermont and New York, which in 2013 had 10 times and 25 times more solar, respectively.
Solar power in Virginia on rooftops is estimated to be capable of providing 32.4% of electricity used in Virginia using 28,500 MW of solar panels. Installing solar panels provides a 6.8% return on investment in Virginia, and a 5 kW array would return a profit of $16,041 over its 25 year life.
