Hanul — South Korea

Hanul is a 6,226 MW nuclear power station in Gangwon-do, South Korea. It is operated by Korea Hydro and Nuclear. Based on its capacity (estimated), it can supply roughly 14 million homes (estimated). It ranks #2 of 216 South Korea power plants by installed capacity. Commissioned in 1988, it is around 38 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 WRI1000218.

Data provenance

Source of the capacity and fuel values:

capacity: GEM · 2026 · L100000500125; fuel: WRI GPPD

In context: how this plant compares

At 6,226 MW, Hanul is well above the median nuclear plant in South Korea (3,000 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.

Key facts

Share of South Korea nuclear capacity

21.1% of 29,469 MW across 8 plants in this dataset

Age among peers

3 of 6 dated nuclear plants in South Korea are older

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

Capacity vs largest nuclear plants in South Korea

Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by Korea Hydro and Nuclear. All plants by this company →

Local climate & thermal context

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 37.1°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 1% 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: 50/100 — 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.

Site climate & environmental severity

This site sits in a corrosive environment (estimated ISO 9223 class C4 — High), with humidity / wetness the leading environmental stress.

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 #2 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.

Nearby power plants

• Samcheok Green power station · Coal · 2,044 MW · Gangwon-do
• Seokmun power station · Biomass · 39 MW · Gangwon-do
• Daejin nuclear power plant · Nuclear · 3,000 MW · Gangwon
• Samcheok Blue power station · Coal · 1,050 MW · Gangwon-do
• Taebaek Wind park · Wind · 18 MW · Gangwon-do
• Samcheok Anthracite power station · Coal · 100 MW · Gangwon

Location

Coordinates 37.0931, 129.383 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions