Japan Power Demonstration Reactor nuclear power plant is a 13 MW nuclear power plant in Ibaraki Prefecture, Japan. It is operated by Japan Atomic Energy Agency [100%]. Based on its capacity (estimated), it can supply roughly 29k homes (estimated). It ranks #527 of 692 Japan power plants by installed capacity. Commissioned in 1965, it is around 61 years old — an older, legacy facility. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, nuclear supplies about 9.1% of Japan's electricity; the national grid averages 477 gCO₂/kWh (32.7% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id GEM_nuc_japandemonstrationre_japan.
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 13 MW, Japan Power Demonstration Reactor nuclear power plant is below the median nuclear plant in Japan (2,070 MW). Technically it is described as boiling 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 Japan Atomic Energy Agency [100%].
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 36.5°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 2% 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 a corrosive environment (estimated ISO 9223 class C4 — High), with humidity / wetness 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 #24 largest nuclear power plant of 24 in Japan by capacity.
Japan has 24 nuclear power plants in this dataset, together about 61,851 MW of capacity.
Coordinates 36.4568, 140.6059 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Japan Power Demonstration Reactor nuclear power plant is a 13 MW nuclear power plant in Ibaraki Prefecture, Japan, commissioned in 1965.
Its output is enough to supply roughly 29,283 homes (estimated).
Japan Power Demonstration Reactor nuclear power plant is operated by Japan Atomic Energy Agency [100%].
