Folsom

Hydro power plant in California, United States of America. Approximate location 38.7067, -121.1584.

HydroCaliforniaUnited States of America

Folsom is a 199 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 774 GWh, it can supply roughly 221,228 homes. It ranks #1303 of 9,833 United States of America power plants by installed capacity. Commissioned in 1955, it is around 71 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).

199MW installed capacity
774GWh reported / yr
221,228homes powered
1955commissioned (~71 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0000441.

Reported generation trend

2013: 342 GWh20132014: 185 GWh20142015: 204 GWh20152016: 594 GWh20162017: 862 GWh20172018: 583 GWh20182019: 774 GWh2019862 GWh

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

Owner

Operated by U S Bureau of Reclamation. All plants by this company →

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 38.7°N — which shapes how much energy it can produce and how its output varies through the year.

16.5°Cannual mean temp
1,307heating degree-days (base 18°C)
763cooling degree-days (base 18°C)
136 melevation

Monthly mean temperature

J: 8 °CJF: 10 °CFM: 12 °CMA: 15 °CAM: 19 °CMJ: 23 °CJJ: 26 °CJA: 25 °CAS: 23 °CSO: 18 °CON: 12 °CND: 8 °CD26 °C

Heating degree-days here run 47% 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: 31/100 — this site sits in the bottom third of the power plants we cover by heating degree-days.

In colder climates, uninsulated hot equipment (boilers, turbines, valves, steam lines) loses proportionally more heat to ambient air — exactly the loss Inzonex modular insulation is designed to cut.

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.

How it compares & nearby plants

The #93 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 101,657 MW of capacity.

Nearby power plants

Location

Coordinates 38.7067, -121.1584 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

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