AI-generated synthesis

Environment & energy — Japan · Synthesis

A major emitter whose emissions are falling, but whose electricity mix remains dependent on coal and gas since the post-Fukushima shutdown of nuclear power — a gradual nuclear restart is underway.

Citoyen2 min read

Citoyen synthesis for the Environment and climate category in Japan. Grounded in sector data (Ministry of the Environment, METI, IEA, OWID). All values are the latest available realized observation — never a forecast. Assessments are distinguished from sourced facts. Data last updated: June 2026.

1. Current situation — where Japan stands on climate

A major emitter on a downward trend. Japan's greenhouse gas emissions are around 1,000 MtCO2e, placing it among the five largest emitters in the world. They have declined in recent years thanks to energy efficiency, the nuclear restart, and population decline.

The Fukushima legacy. The Fukushima (2011) nuclear accident led to the shutdown of the entire nuclear fleet, shifting electricity generation toward imported coal and gas — resulting in a temporary rise in emissions and strong dependence on fossil fuels.

A gradual nuclear restart. Japan has embarked on a gradual restart of its nuclear reactors, now presented as a priority for energy security and climate. Nuclear and renewables are at the heart of the decarbonization strategy.

Persistent coal dependence. Japan remains one of the most coal-dependent developed countries in its electricity mix, which sets it apart from countries like France (nuclear) or the United Kingdom (coal phase-out) and draws international criticism.

Strong energy dependence. Poor in resources, Japan imports almost all of its fossil energy, a major economic and strategic vulnerability that shapes its energy policy.

Environment, energy & climatePrimary KPI

Japan — GHG emissions

1,063 MtCO2e
2024
Source: World Bank· 2026
Citoyen indicator — real data · JP · 2026-06-14
Citoyen indicator — real data · JP · 2026-06-14
The Fukushima accident (2011) pushed Japan toward fossil fuels; the gradual nuclear restart is now a climate priority.

2. Outlook — where the transition is heading

Decarbonizing electricity. Meeting climate targets (carbon neutrality aimed for 2050) requires reducing coal dependence, via the nuclear restart, the development of renewables, and new technologies (hydrogen, ammonia).

The nuclear bet. Restarting and extending the nuclear fleet, along with possible new reactors, is central to the strategy — a sensitive issue in public opinion after Fukushima.

Energy security. Reducing dependence on fossil fuel imports is a strategic objective, at the crossroads of climate, security, and the economy (see Economy category).

Technologies and industry. Japan is betting on low-carbon technologies (hydrogen, batteries, efficiency) to decarbonize its industry and export solutions.

Open questions. Three issues will shape the decade: (1) reducing coal dependence; (2) succeeding in the nuclear restart after Fukushima; (3) strengthening energy security.

The fifth-largest emitter in the world, Japan has reduced its emissions but remains one of the most coal-dependent developed countries.

3. International comparison — Japan among the major emitters

Placed in context, Japan is a major emitter on a downward trend but coal-dependent, whose trajectory has been durably shaped by Fukushima.

Three takeaways. (1) Volume: 5th largest emitter in the world. At ≈ 1,000 Mt, Japan emits more than Germany (≈ 670 Mt) but far less than China (≈ 12,000+) or the United States (≈ 5,500-6,000).

(2) A more carbon-intensive electricity supply. Dependence on coal and gas, inherited from the nuclear shutdown, makes Japanese electricity more carbon-intensive than that of France — a gap the nuclear restart aims to close.

(3) An energy vulnerability. The near-absence of domestic fossil resources makes Japan one of the large countries most dependent on energy imports.

Environment, energy & climatePrimary KPI

China — GHG emissions

15,536 MtCO2e
2024
Source: World Bank· 2026
Environment, energy & climatePrimary KPI

United States — GHG emissions

4,781 MtCO2e
2024
Source: U.S. Department of Energy· 2026
Environment, energy & climatePrimary KPI

Germany — GHG emissions

674 MtCO2e
2024
Source: World Bank· 2026
Environment, energy & climatePrimary KPI

South Korea — GHG emissions

668 MtCO2e
2024
Source: World Bank· 2026
Environment, energy & climatePrimary KPI

France — GHG emissions

378 MtCO2e
2024
Source: World Bank· 2026
Environment, energy & climatePrimary KPI

Japan — GHG emissions

1,063 MtCO2e
2024
Source: World Bank· 2026
International comparison — ghg_emissions · JP · 2026-06-14

International comparison — emissions

CountryGHG emissions (MtCO2e)Coal (electricity)Low-carbon electricity
China≈ 12,000+dominantrising
United States≈ 5,500-6,000decliningaverage
Germany≈ 670phasing outrenewables
South Korea≈ 600significantnuclear + fossil
France≈ 373near zerovery high (nuclear)
Japan≈ 1,000persistentnuclear (restart)

Sources: Ministry of the Environment, IEA, OWID — territorial emissions, latest realized values. China and the United States are included for scale. "≈" indicates a rounded figure.

Data used (data journalism basis)

DataValueSource
GHG emissions≈ 1,000 MtCO2eMinistry of the Environment (Citoyen chart)
Global rank≈ 5th emitterIEA / OWID
Nucleargradual restart (post-Fukushima)METI
Coal (electricity)persistent dependenceMETI / IEA (Citoyen chart)
Energy dependencevery high (fossil imports)METI
Carbon neutrality target2050Ministry of the Environment

Sources (national analyses and references)

Ministry of the Environment (emissions inventory) · METI (Ministry of Economy, Trade and Industry — energy, nuclear) · IEA · Our World in Data.

Methodology note — the synthesis distinguishes sourced facts from assessments, remains neutral, dates each data point, and does not extrapolate beyond the sources. Territorial emissions used. China and the United States are included for scale. All values are the latest available realized observation (no forecast). Note generated by AI, human review required. Same safeguards as the rest of the observatory.