Wind power generation in the USA increased by 7.8% in the first eight months of 2026 compared with the same period in 2025, while installed wind capacity grew by almost 10 GW over the 12 months to the end of August. According to data from the U.S. Energy Information Administration (EIA), renewable electricity generation increased by 10.2% overall, with further growth in solar power and hydropower.
The figures, published in the EIA’s latest Electric Power Monthly report and reviewed by the Sun Day Campaign, show that renewable energy generation grew nearly four times faster than total electricity generation, which increased by 2.6%.
Utility-scale solar generation rose by 20.0%, while small-scale solar output increased by 12.0%. Wind generation grew by 7.8%, hydropower by 4.2% and geothermal power by 3.8%. By comparison, electricity generation from natural gas increased by 2.6% and nuclear power by 1.3%, while coal-fired generation fell by 8.7%.
Wind and solar together accounted for 21.1% of US electricity generation during the first eight months of 2026. Wind contributed 10.6% and solar almost 10.5%. Combined, they generated 44.4% more electricity than coal-fired power plants and 24.8% more than nuclear power plants.
Renewable sources, including biomass, accounted for 28.1% of total US electricity generation by the end of August, up from 26.2% a year earlier.
Between September 2025 and August 2026, US installed wind capacity increased by 9,979 MW, including 800 MW of offshore wind. Utility-scale solar capacity grew by 27,142 MW, while small-scale solar added 6,526 MW. Total renewable energy capacity, including hydropower, biomass and geothermal, increased by 43,498 MW.
Battery energy storage capacity grew by a further 17,587 MW over the same period. By comparison, coal capacity fell by 2,703 MW, natural gas capacity increased by 5,316 MW and nuclear capacity remained unchanged. The net increase in combined fossil fuel and nuclear capacity was 2,613 MW.
The EIA projects further growth in renewable energy capacity over the 12 months to the end of August 2027. Utility-scale wind capacity is expected to increase by 8,312 MW, including 3,355 MW of offshore wind. This would bring total utility-scale wind capacity to around 13.5% of the US generating capacity mix, compared with 13.4% at the start of September 2026.
Utility-scale solar capacity is forecast to increase by 44,603 MW, while other utility-scale renewable sources are expected to add 202 MW. Together, utility-scale renewable energy capacity is projected to grow by 53,117 MW, almost 44% more than the 36,972 MW added during the previous 12 months.
The EIA forecasts no net increase in nuclear generating capacity and a decline of 1,997 MW in fossil fuel capacity over the coming year.
The projections for utility-scale generation exclude small-scale solar. The Sun Day Campaign estimates that this segment could add at least 6,000 MW by September 2027, based on recent installation trends. If this growth materialises, total renewable generating capacity could reach approximately 550 GW, exceeding the projected natural gas capacity of 518.3 GW. Solar power alone would account for 20.7% of total US generating capacity.
The EIA also forecasts that battery energy storage capacity will increase by 23,656 MW by September 2027, a rise of 43.7%, bringing the total to approximately 77.8 GW.
Combined, utility-scale renewable energy and battery storage are projected to add around 76.8 GW of capacity by late summer 2027. Including the anticipated growth in small-scale solar, the total could approach or exceed 83 GW.
