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 Rhode Island has become economical 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. A typical residential installation could pay for itself in utility bill savings in 14 years, and generate a profit for the remainder of its 25 year life. Larger systems, from 10 kW to 5 MW, receive a feed-in tariff of up to 33.45¢/kWh.
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 Alaska has been primarily used in remote locations, such as the Nenana Teen Center near Fairbanks, where long summer days provide most of the electricity generated. In 2015, Alaska ranked 45th in installed solar among U.S. states. Rooftop solar panels could provide 23% of all electricity used in Alaska. Net metering is available for PV systems up to 25 kW but is limited to 1.5% of average demand. IREC best practices, based on experience, recommends no limits to net metering, individual or aggregate, and perpetual roll over of kWh credits.
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.
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 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 Missouri has been a growing industry since the early 2010s. Solar power is capable of generating 42.7% of the electricity used in Missouri from rooftop solar panels totaling 28,300 MW.
Solar power in Idaho comprised 550 MW in 2019. A 2016 report by the National Renewable Energy Laboratory estimated that rooftops alone have the potential to host 4,700 MW of solar panels, and thus provide 26.4% of all electricity used in Idaho. A large increase in the state's solar generating capacity began starting year 2015 when 461 MW of solar power was contracted to be built in Idaho.
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 Vermont provides almost 11% of the state's in-state electricity production as of 2018. A 2009 study indicated that distributed solar on rooftops can provide 18% of all electricity used in Vermont. A 2012 estimate suggests that a typical 5 kW system costing $25,000 before credits and utility savings will pay for itself in 10 years, and generate a profit of $34,956 over the rest of its 25-year life.
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.
Solar power in Wisconsin In 2026, Wisconsin rooftops can accommodate approximately 37 GWs of solar capacity and produce 44,183 GWh of electricity, nearly 70% of the statewide generation in 2019. Net metering is available for systems up to at least 20 kW, and excess generation is credited at retail rate to customers next bill. Some utilities allow net metering up to 100 kW. For Xcel customers, kilowatt credits are rolled over monthly and are reconciled annually at avoided cost. Best practices recommend no limits, either individually or aggregate, and perpetual roll over of kilowatt credits.
Solar power in Tennessee is capable of producing much of the state's electricity; however, the industry remains in early stages in the state. With 129 MW of solar power in 2015, Tennessee ranked 20th among states for installed solar capacity.
