EIA’s 12-Month Number Is 76.7 GW. The 83 GW Headline Adds 6 GW EIA Never Forecast
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Marin Holt
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- EIA 12-month utility-scale renewable and battery additions: 76,662.3 MW
- Utility-scale solar within that total: 43,558.0 MW
- Battery storage within that total: 23,428.9 MW
- Small-scale solar added by SUN DAY Campaign, not EIA: about 6,000 MW
- Projected net fossil fuel capacity change: -1,452.7 MW
The Energy Information Administration projects 76,662.3 MW of new utility-scale renewable and battery capacity in the United States over the 12 months to July 31, 2027, figures it published in its Electric Power Monthly on September 24, 2026 with data through July 31. The number moving through trade coverage this week is about 83 GW. That larger figure is not EIA’s. It adds roughly 6,000 MW of small-scale solar that EIA does not forecast at all, an estimate the SUN DAY Campaign supplied from the average of the past five years.
What EIA actually projects
Utility-scale solar accounts for most of it, at 43,558.0 MW. Wind adds 9,481.8 MW, and 3,355.0 MW of that is offshore. Hydropower, biomass and geothermal together contribute 193.6 MW, which is a rounding error against the solar line. Battery energy storage adds another 23,428.9 MW by August 1, 2027, and those four lines sum to the 76,662.3 MW total.
On the other side of the ledger, EIA projects no new nuclear capacity at all over the same 12 months, and a net decline of 1,452.7 MW in fossil fuel capacity.
Where the extra 6,000 MW comes from
EIA does not publish a 12-month forecast for small-scale solar at all. Its projection covers utility-scale capacity, and rooftop and other behind-the-meter systems sit outside it. The SUN DAY Campaign filled the gap with an assumption: small-scale solar will equal or exceed the roughly 6,000 MW added on average in each of the past five years. Add that to 76,662.3 MW and the total reaches about 82,700 MW, which rounds to the 83 GW now attributed to a federal agency.
The assumption is reasonable and the group states it plainly. The attribution is what drifts. Roughly 6,000 MW of that 82,700 MW headline is an advocacy group’s five-year average rather than a federal projection, and the two halves rest on very different evidence.
The 18-month record behind the forecast
Between February 1, 2025 and July 31, 2026, installed utility-scale solar capacity grew 32.7 percent, or 41,051.6 MW. Small-scale solar grew 17.0 percent, or 9,112.4 MW. Wind grew 8.0 percent, or 12,195.4 MW, and only 800 MW of that was offshore. All renewable sources together added 62,092.0 MW for a gain of 14.6 percent, while utility-scale battery capacity simply doubled over the same stretch, adding 26,629.5 MW.
Conventional capacity moved far less. Coal capacity fell 2.4 percent, or 4,131.8 MW. Nuclear added 800.6 MW, a gain of 0.8 percent, and natural gas rose 1.5 percent, or 7,561.5 MW. All fossil fuels plus nuclear together netted 2,641.0 MW, a gain of 0.3 percent across 18 months.
Why It Matters
Developers, interconnection planners and equipment buyers size their own forecasts against the federal number. EIA stands behind the 76,662.3 MW figure and publishes it. Nobody at EIA published the 6,000 MW small-scale adder, and the SUN DAY Campaign says so directly. Anyone quoting 83 GW in a board paper or a supply agreement is quoting both numbers at once, and only one of them traces back to the agency named in the citation.
The storage line deserves separate attention. At 23,428.9 MW of the 76,662.3 MW total, batteries rank second behind utility-scale solar and well ahead of wind. A capacity outlook that reads as a renewables story is also a storage procurement story.
Critical Perspective
The distinction this story draws is about provenance, not certainty, and it would be easy to over-read. EIA’s 76,662.3 MW is itself a projection of planned capacity rather than a record of delivered capacity. Calling it the auditable half means its components trace back to filings, not that the megawatts will arrive on schedule. A reader who takes 76,662.3 MW as firm and the 6,000 MW as soft has substituted one error for another.
The small-scale assumption also deserves a fairer hearing than a bare label gives it. Over the 18 months this data covers, small-scale solar added 9,112.4 MW, which runs close to the 6,000 MW a year the SUN DAY Campaign projects forward. The weakness is not that the figure is implausible. It is that a five-year average is backward-looking by construction, and the past five years are not obviously a guide to the next twelve months.
Sources
- U.S. Energy Information Administration, Electric Power Monthly, data through July 31, 2026, released September 24, 2026
- Electrek, EIA: 83 GW of renewables and storage coming in 12 months as fossil fuel capacity to fall, September 28, 2026
- SUN DAY Campaign news release, via Energy Central, September 2026
- GreentechLead, U.S. Renewable Energy Hits 29% of Power Generation as Solar, Wind and Batteries Add 88.7 GW, September 2026
