How to read the data

Everything on GridPlants comes from one federal survey, Form EIA-860, which every US generating plant of 1 MW or more must file with the U.S. Energy Information Administration. This page explains what each figure means, how the rankings are computed and where the data stops.

The source

The data are the final 2025 annual files of Form EIA-860 (Annual Electric Generator Report), released on September 10, 2026 and downloaded from eia.gov/electricity/data/eia860 on 2026-10-28. We use four of the files: plants, generators (operable, proposed, and retired and canceled), owners and multifuel. Every value describes the situation at the end of 2025. Later changes, such as a unit that retired in 2026, are not reflected until EIA publishes the next final year.

How to read a plant page

The first paragraph is written from the plant’s own record: it names the operator and then the two to four facts that most set the plant apart from others, chosen by a fixed set of rules (below). Next to it, the big number is the plant’s nameplate capacity, the sum of the manufacturer ratings of its operable generators. The bar under it splits that capacity by technology.

The unit-by-unit chart draws one bar per generator, from the year it came online to 2025. Bar height grows with the unit’s nameplate rating. Grey bars are units retired at this plant (EIA keeps retired units on file), ending in the year they left service. A dashed tail marks a retirement date the operator has reported as planned. On plants with many units, units of the same technology and start year share one bar.

Measures and their scope

Nameplate capacity: The generator’s full-load rating in megawatts (MW) as set by the manufacturer. All rankings on this site use nameplate capacity of operable units (statuses operating, standby, and out of service).
Net summer capacity: The maximum output the operator reports the unit can deliver to the grid in summer, after the plant’s own use. It is shown next to nameplate but never mixed with it in a ranking.
Main fuel: The fuel group with the largest share of a plant’s nameplate capacity. Groups follow EIA’s technology field: natural gas (combined cycle, combustion turbine, engine, steam), coal, nuclear, hydroelectric, pumped-storage hydro, wind, solar (photovoltaic and thermal), battery storage (including flywheels), oil and petroleum coke, biomass and waste (wood, landfill gas, municipal solid waste, other biomass), geothermal and other.
First unit online: The operating year of the oldest generator that is still operable. Units that were retired are not counted, so a site that opened earlier and later replaced its first units shows a later year.
Retired units: Generators reported as retired at a plant that still has at least one operable unit. Whole plants that have closed have no page here; their retired capacity is included only in the national retirement columns on the home and fuel pages.
Reported plans: Planned retirement years and proposed new units exactly as operators reported them for 2025. Plans change; they are shown as reported, never as forecasts.
Balancing area: The balancing authority named on the plant record: the organization that matches electricity supply and demand in real time within its area.
Operator and owners: The operator is the reporting utility that runs the plant. Owners come from the ownership file, which lists only generators that are jointly owned or not wholly owned by the operator; a share is weighted by the nameplate capacity of each unit an owner holds.
Closest plants: Straight-line distance between the reported coordinates of two plants, in miles, with the compass direction from the page’s plant.

Rankings

Ranks compare plants within a stated group: all 14,286 plants, the plants of one state, the plants with the same main fuel nationally or in one state, the plants of one balancing area or one operator. Plants with the same value share a rank. Age ranks order plants by the year of their oldest operable unit, earliest first.

Which plants have their own page

A plant gets a page when it has at least 50 MW of nameplate capacity and at least three strong distinguishing facts, or at least two such facts and 1,000 MW or more. Strong facts are: a top-50 national rank; a top-5 rank in its state; a top-10 rank among plants with the same main fuel nationally; the largest plant of its fuel in its state; a top-3 rank in its balancing area; one of the three largest single units in its state (100 MW or more); the earliest or second-earliest first unit among plants of its fuel in its state (1990 or before), or a top-10 national age rank for its fuel; units on three or more fuel groups; 200 MW or more of retired units; 100 MW or more added in 2023–2025; 100 MW or more with a reported retirement year; 100 MW or more of proposed units; three or more listed owners. That gives 253 plant pages. All other plants are listed in the finder and in the state, fuel, area and operator pages.

Data cleaning

We applied these rules and dropped or blanked the records shown. Plants run by an individual person and ownership records naming an individual are left out, because this site lists companies and public bodies only.

summer capacity < 0 or > 1.6 x nameplate set to missing (nameplate kept): 40
plant dropped: operator is an individual person: 4
plant dropped: missing or out-of-range coordinates: 28
ownership record dropped: owner is an individual person: 8
plants with at least one operable generator (all sizes) kept: 14,323
plants under 1 MW nameplate total removed (EIA-860 threshold is 1 MW): 37

Licence and credit

EIA data are a work of the U.S. Government and in the public domain; EIA asks that it be credited as the source. Credit line: Source: U.S. Energy Information Administration, Form EIA-860 (Annual Electric Generator Report), 2025 final data (Sep 2026). GridPlants is an independent site and is not endorsed by EIA. Figures on this site are summaries computed from the EIA files; for official statistics see EIA’s own publications.