SUN DAY CAMPAIGN
Over the Past Year, Renewable Generation Expanded >10% While Capacity Grew by 43.5-GW; Another 59-GW Expected in the Coming Year as Fossil Fuels Decline`

HIGHLIGHTS

• THROUGH AUGUST, EIA DATA SHOW ELECTRICITY PRODUCTION BY RENEWABLES GREW >10% AS THEY GENERATED OVER 28% OF THE U.S. TOTAL
• RENEWABLES AND BATTERIES ADDED 61-GW IN PAST YEAR;
• THEY WILL GROW BY 83-GW IN THE COMING YEAR AS RENEWABLES TOP 40% OF GENERATING CAPACITY

New data recently released by the U.S. Energy Information Administration (EIA), and reviewed by the SUN DAY Campaign, reveal growth of over 10% in electrical generation by renewable energy sources in the first two-thirds of 2026. Moreover, renewables and battery storage are projected to add about 82.8 gigawatts (GW) of new generating capacity in the U.S. by August 31, 2027 while total fossil fuel and nuclear power capacity will fall by almost 2-GW.

Over the coming year, renewables' share of total generating capacity will grow from 37.7% to 40.4% and surpass that of natural gas as well as swamp nuclear capacity five-fold.

Electrical generation by renewables sources grew by more than 10% during the past year and was over 28% of the U.S. total in the first two-thirds of 2026.

According to the EIA's latest "Electric Power Monthly" report (with data through August 31, 2026), renewably-generated electricity during the first two-thirds of 2026 was 10.2% greater than in the same period of 2025. The growth was led by utility-scale [i.e., >1-MW] solar (up 20.0%), small-scale [i.e., <1-MW] solar (up 12.0%), wind (up 7.8%), hydropower (up 4.2%), and geothermal (up 3.8%). [1]

By comparison, the electrical output of the nation's natural gas and nuclear power plants experienced slower growth - just 2.6% and 1.3% respectively. Electricity produced by U.S. coal facilities fell by 8.7%.

Taken together, generation by all sources combined increased 2.6%. Thus, the rate of renewables' growth was nearly four times the national average.

During the first eight months of 2026, the combination of just wind and solar, including small-scale solar, provided almost 21.1% of domestic electrical production with wind accounting for 10.6% and solar nearly 10.5%.

During the first two-thirds of this year, wind and solar combined produced 44.4% more electricity than the nation's coal plants and 24.8% more than its nuclear reactors. [2]

Through the end of August, the mix of all renewables, including biomass, accounted for 28.1% of total U.S. electrical generation - up from 26.2% a year earlier.

Over the past year, renewable energy capacity increased by over 43,000-MW. [3]

Between September 1, 2025 and August 31, 2026, the installed capacity of utility-scale solar increased by 27,141.7-MW while that of small-scale solar and wind grew by 6,526.1-MW and 9,979.1-MW (including 800-MW of offshore wind) respectively. The combined capacity of all renewable energy sources - including hydropower, biomass, and geothermal - expanded by 43,497.9-MW.

In addition, utility-scale battery energy storage capacity increased by 17,586.9-MW.

By comparison, coal capacity fell by 2,703.4-MW and nuclear remained unchanged. However, natural gas capacity rose by 5,316.0-MW. Combined, net new nuclear and fossil fuel capacity totaled just 2,612.6-MW

Thus, renewable energy's capacity expansion was nearly 17 times greater than the net growth of fossil fuels and nuclear power combined.

Utility-scale renewable energy to add over 53-GW of new capacity in the coming year; small-scale solar likely to grow by >6-GW.

The rapid growth experienced by renewables during the past year is projected to accelerate in the coming year.

As of September 1, 2026, renewable energy's share of total U.S. utility-scale generating capacity was 34.5%. EIA projects this to grow to 37.3% by August 31, 2027. Utility-scale solar will add 44,603.1-MW thereby expanding its share from 13.4% to 16.5% while wind will grow by 8,312.3-MW (including 3,355.0-MW of offshore wind), increasing from 13.4% to 13.5%. The mix of other renewables (i.e., hydropower, biomass, and geothermal) will add 201.9-MW.  

The combined net capacity growth of all utility-scale renewable energy sources for the 12-month period (53,117.3-MW) is almost 44% more than that added during the previous 12 months (36,971.8-MW). It would bring renewables' share of total U.S. utility-scale generating capacity up to 37.3%.

Meanwhile, EIA projects no new generating capacity by nuclear power and a net decline of 1,997.0-MW in fossil fuel capacity. [4]

With the inclusion of new small-scale solar, renewables' capacity is on track to surpass natural gas by summer 2027.

The figures cited above do not include small-scale solar. [5] The estimated capacity of small-scale solar systems grew by 6,526.1-MW during the last year, bringing its total to 63,192.6-MW. EIA does not provide a forecast for the next 12 months for small-scale solar capacity growth but the SUN DAY Campaign assumes it will roughly equal the 6,400-MW that have been added on average during each of the past five years. Therefore, it is conservatively assumed that an additional 6,000-MW or more will come on-line in the coming year. [6]

If small-scale solar does increase by approximately 6,000-MW by September 1, 2027, it will bring renewable energy's installed capacity up to about 550,000-MW. By comparison, natural gas' projected generating capacity would total 518,312.8-MW.

Solar power's share alone would be more than one-fifth (20.7%) of total U.S. generating capacity.  

Battery energy storage is projected to increase by almost 44% by next September:

EIA foresees battery energy storage adding another 23,656.2-MW by September 1, 2027 - an increase of 43.7%, bringing the total up to 77,753.2-MW.

Thus, the combination of utility-scale renewable energy sources and battery energy storage will provide 76,773.5-MW of new clean energy capacity by late summer 2027. With the inclusion of small-scale solar, that figure could rise close to, or surpass, 83,000-MW.

"Each new issue of EIA's Electric Power Monthly' reinforces the theme that the growth of solar, wind, and battery storage has become unstoppable," noted the SUN DAY Campaign's executive director Ken Bossong. "Meanwhile, the share of the nation's electrical generation and generating capacity provided by fossil fuels and nuclear continues to shrink."

Sources:

EIA released its latest "Electric Power Monthly" report, with data through August 31, 2026, on October 23, 2026. The full report can be found at: https://www.eia.gov/electricity/monthly

For the data cited in this release, see:

Table ES1.A ("Total Electric Power Industry Summary Statistics, 2026 and 2025");

Table ES1.B ("Total Electric Power Industry Summary Statistics, Year-to-Date 2026 and 2025");

Table 1.1.A ("Net Generation from Renewable Sources"); and

Table 6.1 ("Electric Generating Summer Capacity Changes (MW), July 2026 to August 2026").

Notes:   

[1] In January-August 2026, wind produced 333,367 gigawatt-hours (GWh) - 10.6% of total U.S. electrical generation - while utility-scale and small-scale solar combined produced 329,119-GWh (10.5%), hydropower produced 180,940-GWh (5.7%), biomass produced 29,917-GWh (1.0%), and geothermal produced 10,766-GWh (0.34%).

[2] In January-August 2026, the mix of wind and solar, including small-scale solar, produced 662,486-GWh while nuclear power generated 531,031-GWh and coal provided 458,609-GWh.

[3] EIA presents its capacity data as "summer capacity" defined as the maximum output that generating equipment can supply to system load at the time of summer peak demand. See Table 6.1 in the "Electric Power Monthly" report.

[4] Note that capacity factors for fossil fuels and nuclear power are generally higher than for solar and wind. For calendar year 2025, EIA reported capacity factors of 48.7%, 58.4%, and 91.0% for coal, natural gas, and nuclear power respectively. By comparison, the capacity factors for wind and utility-scale PV were 34.2% and 24.4% respectively. See Tables 6.07.A and 6.07.B. Capacity factors for small-scale solar systems (10%-25%.) are usually lower than for utility-scale solar.

[5] In its "Electric Power Monthly" report, EIA refers to small-scale or distributed solar as "Estimated Small Scale Solar Photovoltaic." Unless otherwise indicated, all calculations presented in this release include electrical generation by small-scale solar which EIA estimates to have totaled 73,765-GWh in January-August 2026. Utility-scale solar totaled 255,354-GWh for the same period.

[6] Between September 1, 2025 and August 31, 2026, estimated small-scale solar accounted for 6,526.1-MW in new capacity additions. The SUN DAY Campaign is therefore assuming that at least 6,000-MW in new small-scale solar capacity will be added during the coming 12 months.

The SUN DAY Campaign is a non-profit research and educational organization founded in 1992 to support a rapid transition to 100% reliance on sustainable energy technologies as a cost-effective alternative to nuclear power and fossil fuels and as a solution to climate change.