Solar power in Massachusetts has been increasing rapidly, due to Section 1603 grants for installations that began before December 31, 2011, and the sale of SRECs for $0.30/kWh, which allows payback for the system within 5 or 6 years, and generates income for the life of the system. For systems installed after December 31, 2011, and before December 31, 2016, the 30% tax grant becomes a 30% tax credit. There has been an appeal to the Congress to extend the 1603 program, the grant program, for an additional year.
New York has a renewable portfolio standard of 30% from renewable sources by 2015. In 2015 24% was renewable, 6% short of the goal. Wind is the predominant generating technology. In 2018, the New York State Energy Research and Development Authority awarded long-term contracts to 22 utility-scale solar farms, totaling a combined capacity of 646 MW.
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 Wyoming has the potential to generate 72 million MWh/yr. Wyoming used 12 million MWh in 1999. Net metering is available to all consumers generating up to 25 kW. The state has an installed capacity of 146 MW as of 2022.
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 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 Maryland is supported by the state's legislation regarding the Renewable Portfolio Standard and Solar Renewable Energy Credit (SREC) program. The target for renewable energy as of 2017 is 20% by 2020, including 2% from solar power.
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 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 Delaware is small industry. Delaware had 150 MW of total installed capacity in 2020. The largest solar farms in the state included the 10 MW Dover Sun Park and the 12 MW Milford Solar Farm.
