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Columbia nuclear power plant

Nuclear power plant in Washington, United States of America. Approximate location 46.4711, -119.3339.

NuclearWashingtonUnited States of AmericaBWR-5 (Mark 2)boiling water reactor

Columbia nuclear power plant is a 1,190 MW nuclear power station in Washington, United States of America. It is operated by Energy Northwest [100%]. Based on its capacity (estimated), it can supply roughly 2.7 million homes (estimated). It ranks #538 of 10,938 United States of America power plants by installed capacity. Commissioned in 1984, it is around 42 years old — long-established. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, nuclear supplies about 17.4% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).

1,190MW installed capacity
12construction time (1972→1984)
2,680,560homes powered (est.)
1984commissioned (~42 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id GEM_nuc_columbia_unite.

Data status

Known data

FacilityColumbia nuclear power plant GEM-nuclear
CountryUnited States of America · Washington GEM-nuclear
Coordinates46.4711, -119.3339 GEM-nuclear
FuelNuclear GEM-nuclear
MW installed capacity1,190 MW GEM · 2026 · L100000500057; operating plant capacity
OwnerEnergy Northwest [100%] GEM-nuclear
Commissioned1984 GEM-nuclear
Technologyboiling water reactor GEM-nuclear

Calculated from dataset

Capacity rank in country#538 / 10938 calculated
Fuel-specific rank in country#156 / 230 calculated
Capacity vs country/fuel peers0.62× · 1,917 MW · n=230 calculated
Homes-powered equivalent2,680,560 calculated
Climate11.7°C · HDD 2,661 derived from coordinates
Environmental severityC1 · 36/100 derived from coordinates

Not available

GWh reported / yrNot available not in dataset
CO₂ emissionsnot applicable not applicable

Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.

Capacity provenance

The public capacity above is a source-verified 2026 capacity claim: 1,190 MW for Columbia nuclear power plant.

GEM · 2026 · operating plant capacity

Data provenance

The capacity and/or fuel fields on this page include a source-backed provenance label from GEM, an official registry, Wikidata, OSM, or a cross-source match.

capacity: GEM · 2026 · L100000500057; fuel: GEM GNPT

In context: how this plant compares

At 1,190 MW, Columbia nuclear power plant is below the median nuclear plant in United States of America (1,917 MW). Technically it is described as boiling water reactor. Nuclear plants split uranium to raise steam with no direct CO₂; they run as steady baseload with very high capacity factors and the longest operating lifetimes of any thermal plant.

Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.

Capacity vs largest nuclear plants in United States of America

Palo Verde nuclear power plant: 6,782 MW7kPalo Verde…Comanche Peak nuclear power plant: 5,909 MW6kComanche P…Shearon Harris nuclear power plant: 5,895 MW6kShearon Ha…North Anna nuclear power plant: 5,615 MW6kNorth Anna…South Texas nuclear power plant: 5,416 MW5kSouth Texa…Alvin W Vogtle nuclear power plant: 4,958 MW5kAlvin W Vo…Hartsville nuclear power plant: 4,876 MW5kHartsville…Bellefonte nuclear power plant: 4,746 MW5kBellefonte…

Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by Energy Northwest [100%].

Local climate & thermal context

This nuclear plant uses heat from nuclear fission to raise steam for a turbine-generator. It sits in a cold semi-arid steppe climate (Köppen BSk) — Northern Hemisphere, latitude 46.5°N — which shapes how much energy it can produce and how its output varies through the year.

11.7°Cannual mean temp
2,661heating degree-days (base 18°C)
386cooling degree-days (base 18°C)
180 melevation

Monthly mean temperature

J: 0 °CJF: 4 °CFM: 8 °CMA: 12 °CAM: 16 °CMJ: 20 °CJJ: 24 °CJA: 23 °CAS: 18 °CSO: 12 °CON: 5 °CND: 0 °CD24 °C

Heating degree-days here run 8% above the median power plant in this dataset — a proxy for how much extra energy heated equipment must replace through its surfaces in winter.

Climate heat-demand index: 53/100 — this site sits in the mid third of the power plants we cover by heating degree-days.

Climate normals: WorldClim 2.1 (1970–2000 monthly normals, 10 arc-min, CC BY 4.0); zone: Köppen-Geiger world climate classification (Kottek et al. 2006, 0.5° grid). Degree-days & heat-demand index computed by PowerAtlas — a modelled heat-demand proxy, not a measured site figure.

Site climate & environmental severity

For a plant’s outdoor hardware — heat-recovery steam generators (HRSG), expansion joints, valves, flanges and their insulation — the local climate sets how fast unprotected steel and coatings degrade. This site sits in a benign, low-corrosion environment (estimated ISO 9223 class C1 — Very low), with dust abrasion the leading environmental stress.

C1ISO 9223 corrosivity (indicative)
36/100environmental-severity index
23.2°Cseasonal temperature swing
326 kmdistance to coast

Higher environmental severity is exactly where protective removable insulation pays back most: a sheltered micro-climate slows corrosion, UV and thermal-cycling damage and extends outdoor hardware service life. This is an indicative site-climate context — not a condition assessment of any specific plant or operator.

Indicative estimate via the ISO 9223:2012 informative method (atmospheric corrosivity from temperature, time-of-wetness and airborne salinity), using WorldClim climate normals, the Köppen-Geiger class and coast distance. Indicative, not a measured corrosion rate.

How it compares & nearby plants

The #156 largest nuclear power plant of 230 in United States of America by capacity.

United States of America has 230 nuclear power plants in this dataset, together about 427,888 MW of capacity.

Nearby power plants

Location

Coordinates 46.4711, -119.3339 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions

What type of power plant is Columbia nuclear power plant?

Columbia nuclear power plant is a 1,190 MW nuclear power plant in Washington, United States of America, commissioned in 1984.

How many homes can Columbia nuclear power plant power?

Its output is enough to supply roughly 2,680,560 homes (estimated).

Who operates Columbia nuclear power plant?

Columbia nuclear power plant is operated by Energy Northwest [100%].

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