Nuclear power plant in Alaska, United States of America. Approximate location 63.97376, -145.7178.
NuclearAlaskaUnited States of Americapressurized water reactor
SM-1A nuclear power plant is a 1.6 MW nuclear power plant in Alaska, United States of America. It is operated by US Department of Defense [100%]. Based on its capacity (estimated), it can supply roughly 3.6k homes (estimated). It ranks #9724 of 10,938 United States of America power plants by installed capacity. Commissioned in 1962, it is around 64 years old — an older, legacy facility. 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).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id GEM_nuc_sm1a_unite.
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
The capacity and fuel fields on this page are source-record values from the upstream open dataset. They are useful for identification and ranking, but they have not been upgraded to a 2026 registry/GEM-location verified value.
capacity: GEM GNPT; fuel: GEM GNPT
At 1.6 MW, SM-1A nuclear power plant is below the median nuclear plant in United States of America (1,917 MW). Technically it is described as pressurized 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.
Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).
Operated by US Department of Defense [100%].
This nuclear plant uses heat from nuclear fission to raise steam for a turbine-generator. It sits in a Mediterranean subarctic climate (Köppen Dsc) — Northern Hemisphere, latitude 64.0°N — which shapes how much energy it can produce and how its output varies through the year.
Monthly mean temperature
Heating degree-days here run 212% 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: 100/100 — 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.
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 thermal cycling the leading environmental stress.
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.
The #229 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.
Coordinates 63.97376, -145.7178 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
SM-1A nuclear power plant is a 1.6 MW nuclear power plant in Alaska, United States of America, commissioned in 1962.
Its output is enough to supply roughly 3,604 homes (estimated).
SM-1A nuclear power plant is operated by US Department of Defense [100%].
