Nuclear power plant in Ulsan, South Korea. Approximate location 35.7111, 129.4743.
NuclearUlsanSouth KoreaCANDU 6pressurized heavy water reactor
Wolsong is a 2,799 MW nuclear power station in Ulsan, South Korea. It is operated by Korea Hydro and Nuclear. Based on its capacity (estimated), it can supply roughly 6.3 million homes (estimated). It ranks #14 of 216 South Korea power plants by installed capacity. Commissioned in 1983, it is around 43 years old — long-established. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, nuclear supplies about 29.6% of South Korea's electricity; the national grid averages 417 gCO₂/kWh (40.0% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id WRI1000215.
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
The public capacity above is the current source-record value. A 2026 tracker candidate lists 1,812 MW for Wolsong nuclear power plant, but it is not used as the public primary value until scope is verified (unit vs operating vs installed/project total).
Capacity claim grade: A3_MAJOR_REVIEW_SCOPE_STATUS - recommended action: manual_scope_status_check - confidence: low_until_scope_verified. This follows a claim-based data model: value + scope + source + confidence, rather than silently overwriting records.
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: WRI Global Power Plant Database source-record (legacy); fuel: WRI source-record fuel
At 2,799 MW, Wolsong is around the median nuclear plant in South Korea (3,000 MW). Technically it is described as pressurized heavy 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 Korea Hydro and Nuclear. All plants by this company →
This nuclear plant uses heat from nuclear fission to raise steam for a turbine-generator. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 35.7°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 3% 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: 49/100 — this site sits in the mid 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 an aggressive, high-corrosion environment (estimated ISO 9223 class C5 — Very high), with marine salt corrosion 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 #6 largest nuclear power plant of 8 in South Korea by capacity.
South Korea has 8 nuclear power plants in this dataset, together about 29,469 MW of capacity.
Coordinates 35.7111, 129.4743 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Wolsong is a 2,799 MW source-record nuclear power plant in Ulsan, South Korea, commissioned in 1983.
Its output is enough to supply roughly 6,304,947 homes (estimated).
Wolsong is operated by Korea Hydro and Nuclear.
