Home / North America / United States of America / Summer Falls Power Plant

Summer Falls Power Plant

Hydro power plant in Washington, United States of America. Approximate location 47.5025, -119.2917.

HydroWashingtonUnited States of America

Summer Falls Power Plant is a 92 MW hydro power plant in Washington, United States of America. It is operated by Columbia Basin Hydropower. Based on reported annual generation of 330 GWh, it can supply roughly 94k homes. It ranks #2960 of 10,938 United States of America power plants by installed capacity. Commissioned in 1985, it is around 41 years old — long-established. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, hydro supplies about 5.3% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).

92Source-backed capacity
330GWh reported / yr
94,428homes powered
1985commissioned (~41 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0056695.

Data status

Known data

FacilitySummer Falls Power Plant WRI
CountryUnited States of America · Washington WRI
Coordinates47.5025, -119.2917 WRI
FuelHydro WRI
MW installed capacity92 MW WRI source record; scope not independently normalised
OwnerColumbia Basin Hydropower WRI
Commissioned1985 WRI
GWh reported / yr330 GWh/yr WRI

Calculated from dataset

Capacity rank in country#2960 of 10938 calculated
Fuel-specific rank in country#202 of 1449 calculated
Capacity vs country/fuel peers11.50× · 8 MW median · 1449 peers calculated
Homes-powered equivalent94,428 calculated from reported generation
Climate10.0°C · HDD 3,177 derived from coordinates
Environmental severityC1 · 36/100 derived from coordinates

Not available

TechnologyNot available not in dataset
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.

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 tracker 2026 (location L100000603936); fuel: WRI source-record fuel

In context: how this plant compares

At 92 MW, Summer Falls Power Plant is well above the median hydro plant in United States of America (8 MW). Hydropower converts the energy of falling or flowing water into electricity; output depends on rainfall and reservoir level, and large dams also provide grid balancing and storage.

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

Reported generation trend

2013: 375 GWh20132014: 406 GWh20142015: 398 GWh20152016: 380 GWh20162017: 340 GWh20172018: 361 GWh20182019: 330 GWh2019406 GWh

Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by Columbia Basin Hydropower.

Local climate & thermal context

This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a cold semi-arid steppe climate (Köppen BSk) — Northern Hemisphere, latitude 47.5°N — which shapes how much energy it can produce and how its output varies through the year.

10.0°Cannual mean temp
3,177heating degree-days (base 18°C)
287cooling degree-days (base 18°C)
445 melevation

Monthly mean temperature

J: -2 °CJF: 1 °CFM: 6 °CMA: 10 °CAM: 15 °CMJ: 19 °CJJ: 22 °CJA: 22 °CAS: 17 °CSO: 10 °CON: 3 °CND: -2 °CD22 °C

Heating degree-days here run 29% 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: 67/100 — this site sits in the top 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
24.7°Cseasonal temperature swing
397 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 #202 largest hydro power plant of 1449 in United States of America by capacity.

United States of America has 1449 hydro power plants in this dataset, together about 102,513 MW of capacity.

Nearby power plants

Location

Coordinates 47.5025, -119.2917 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions

What type of power plant is Summer Falls Power Plant?

Summer Falls Power Plant is a 92 MW source-record hydro power plant in Washington, United States of America, commissioned in 1985.

How much electricity does Summer Falls Power Plant generate?

Summer Falls Power Plant generates about 330 GWh of electricity per year.

How many homes can Summer Falls Power Plant power?

Its output is enough to supply roughly 94,428 homes.

Who operates Summer Falls Power Plant?

Summer Falls Power Plant is operated by Columbia Basin Hydropower.

Built from open public data; no personal information. Operate this site? Request a correction or removal.