Plant counts by primary fuel, WRI Global Power Plant Database (CC BY 4.0).
Source: Ember / Our World in Data (CC BY 4.0).
Across the 125 Japan power plants carrying an asset-level CO₂ figure in this open dataset, total emissions are about 246 Mt CO₂/yr. The single largest emitter, Kobe power station (coal), accounts for about 6% of that 125-plant reported subset (not of the whole country). The top three owners — J-POWER, Tohoku Electric Power Co, Kobelco Power Kobe Inc. — control roughly 32% of that 125-plant reported subset. Most of these plants sit in a temperate Köppen climate zone.
CO₂ — measured (US EPA / EU ETS) or modelled (Climate TRACE), per plant · backbone WRI Global Power Plant Database (CC BY 4.0) · climate: Köppen-Geiger (WorldClim). CC BY 4.0.
| # | Plant | Fuel | MW |
|---|---|---|---|
| 1 | Kashiwazaki Kariwa | Nuclear | 7,965 |
| 2 | Fukushima Daiichi nuclear power plant | Nuclear | 7,456 |
| 3 | Futtsu | Gas | 5,334 |
| 4 | Higashi Niigata | Gas | 4,810 |
| 5 | Kawagoe | Gas | 4,802 |
| 6 | Ohi | Nuclear | 4,710 |
| 7 | Fukushima Daina | Nuclear | 4,400 |
| 8 | Hirono | Oil | 4,400 |
| 9 | Kashima | Oil | 4,400 |
| 10 | Hekinan power station | Coal | 4,100 |
| 11 | Chita | Oil | 3,966 |
| 12 | Sodegaura | Gas | 3,600 |
| 13 | Hamaoka | Nuclear | 3,504 |
| 14 | Genkai | Nuclear | 3,478 |
| 15 | Takahama | Nuclear | 3,392 |
| 16 | Anegasaki | Oil | 3,150 |
| 17 | Shin Nagoya | Gas | 3,058 |
| 18 | Yokohama | Oil | 3,016 |
| 19 | Himeji Daini | Gas | 2,919 |
| 20 | Chiba | Gas | 2,880 |
Inzonex PowerAtlas (2026). Asset-level power-plant CO2 emissions — Japan. Derived from WRI GPPD, Climate TRACE, US EPA GHGRP and EU ETS (CC BY 4.0). https://inzonex.co.uk/poweratlas/japan/
There are 692 power plants in Japan in this open dataset, with about 278,871 MW of total capacity.
Kashiwazaki Kariwa is the largest at about 7,965 MW (nuclear).
The most common plant type in this dataset is solar (324 plants), across 11 fuel types in total.
Japan's grid carbon intensity is about 477 gCO₂/kWh, with 32.7% low-carbon generation (<a href="https://ember-energy.org/" rel="nofollow">Ember</a> / <a href="https://ourworldindata.org/energy" rel="nofollow">Our World in Data</a> (CC BY 4.0)).
Power plants in Japan