Keswick — United States of America

Hydro power plant in California, United States of America. Approximate location 40.6119, -122.4464.

HydroCaliforniaUnited States of America

Keswick is a 117 MW hydro power station in California, United States of America. It is operated by U S Bureau of Reclamation. Based on reported annual generation of 356 GWh, it can supply roughly 102k homes. It ranks #2559 of 10,884 United States of America power plants by installed capacity. Commissioned in 1949, it is around 77 years old — an older, legacy facility. 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).

117MW installed capacity
356GWh reported / yr
101,714homes powered
1949commissioned (~77 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0000443.

Data status

Known data

FacilityKeswick WRI
CountryUnited States of America · California WRI
Coordinates40.6119, -122.4464 WRI
FuelHydro WRI
MW installed capacity117 MW GEM · 2026 · L100000603843; operating plant capacity
Verification noteQuality label backfilled from existing source-backed capacity provenance on 2026-07-05; capacity value was not changed. source-verified
OwnerU S Bureau of Reclamation WRI
Commissioned1949 WRI
GWh reported / yr356 GWh·a⁻¹ WRI

Calculated from dataset

Capacity rank in country#2559 / 10884 calculated
Fuel-specific rank in country#160 / 1449 calculated
Capacity vs country/fuel peers14.62× · 8 MW · n=1449 calculated
Homes-powered equivalent101,714 calculated from reported generation
Climate16.6°C · HDD 1,406 derived from coordinates
Environmental severityC3 · 37/100 derived from coordinates

Not available

TechnologyNot 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

Source of the capacity and fuel values:

capacity: GEM · 2026 · L100000603843; fuel: WRI GPPD

In context: how this plant compares

At 117 MW, Keswick 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.

Key facts

Load factor
35%, from 356 GWh of reported generation; the median for 1342 hydro plants in United States of America that report generation is 42%
Generation trend
384 GWh in 2013 and 356 GWh in 2019 (−7%)
Highest and lowest year
2017: 437 GWh; 2015: 278 GWh
Share of United States of America hydro capacity
0.1% of 102,513 MW across 1,449 plants in this dataset
Age among peers
546 of 1,444 dated hydro plants in United States of America are older

Calculated from the capacity and generation records in this dataset (WRI Global Power Plant Database (CC BY 4.0)).

Reported generation trend

2013: 384 GWh20132014: 284 GWh20142015: 278 GWh20152016: 333 GWh20162017: 437 GWh20172018: 325 GWh20182019: 356 GWh2019437 GWh

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

Local climate & thermal context

This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a hot-summer Mediterranean climate (Köppen Csa) — Northern Hemisphere, latitude 40.6°N — which shapes how much energy it can produce and how its output varies through the year.

16.6°Cannual mean temp
1,406heating degree-days (base 18°C)
916cooling degree-days (base 18°C)
230 melevation

Monthly mean temperature

J: 8 °CJF: 10 °CFM: 11 °CMA: 14 °CAM: 19 °CMJ: 23 °CJJ: 27 °CJA: 27 °CAS: 24 °CSO: 18 °CON: 11 °CND: 8 °CD27 °C

Heating degree-days here run 43% below 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: 32/100 — this site sits in the bottom 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

This site sits in a moderately corrosive environment (estimated ISO 9223 class C3 — Medium), with humidity / wetness the leading environmental stress.

C3ISO 9223 corrosivity (indicative)
37/100environmental-severity index
19.5°Cseasonal temperature swing
138 kmdistance to coast

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 #160 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 40.6119, -122.4464 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions

What type of power plant is Keswick?

Keswick is a 117 MW hydro power plant in California, United States of America, commissioned in 1949.

How much electricity does Keswick generate?

Keswick generates about 356 GWh of electricity per year.

Who operates Keswick?

Keswick is operated by U S Bureau of Reclamation.

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