Seminoe

Hydro power plant in Wyoming, United States of America. Approximate location 42.1561, -106.9085.

HydroWyomingUnited States of America

Seminoe is a 52 MW hydro power plant in Wyoming, United States of America. It is operated by U S Bureau of Reclamation. Based on reported annual generation of 141 GWh, it can supply roughly 40,342 homes. It ranks #2686 of 9,833 United States of America power plants by installed capacity. Commissioned in 1939, it is around 87 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).

52MW installed capacity
141GWh reported / yr
40,342homes powered
1939commissioned (~87 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0004182.

Reported generation trend

2013: 90 GWh20132014: 120 GWh20142015: 125 GWh20152016: 138 GWh20162017: 128 GWh20172018: 105 GWh20182019: 141 GWh2019141 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 warm-summer humid continental climate (Köppen Dfb) — Northern Hemisphere, latitude 42.2°N — which shapes how much energy it can produce and how its output varies through the year.

5.7°Cannual mean temp
4,507heating degree-days (base 18°C)
28cooling degree-days (base 18°C)
2,087 melevation

Monthly mean temperature

J: -7 °CJF: -4 °CFM: 0 °CMA: 4 °CAM: 9 °CMJ: 15 °CJJ: 19 °CJA: 18 °CAS: 13 °CSO: 7 °CON: 0 °CND: -5 °CD19 °C

Heating degree-days here run 83% 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: 91/100 — this site sits in the top 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 #288 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 42.1561, -106.9085 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

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