Japan
Overview
Japan operates a partially liberalized electricity market with significant legacy clean energy resources from nuclear and hydropower. The country is actively rebuilding its nuclear fleet following the 2011 Fukushima disaster, making it a high-potential SSS jurisdiction.
| Metric | Value |
|---|---|
| SSS Relevance | ⭐⭐⭐ High |
| Grid Carbon Intensity | ~450-500 gCO2/kWh |
| Renewable Share | ~26.7% (2024) |
| Nuclear Share | ~8% (2024, growing) |
| Market Type | Partially Liberalized |
Market Structure
Japan's electricity market was fully liberalized for retail customers in 2016. The market is overseen by the Organization for Cross-regional Coordination of Transmission Operators (OCCTO) and regulated by the Ministry of Economy, Trade and Industry (METI).
Key market features:
- Regional utilities: 10 major regional electric power companies (General Electricity Utilities)
- Retail liberalization: Full competition since April 2016
- Wholesale market: Japan Electric Power Exchange (JEPX)
- Transmission: Unbundled from generation (legal separation)
Major utilities (SSS-relevant):
- Tokyo Electric Power Company (TEPCO) — largest, serves Kanto region
- Kansai Electric Power Company (KEPCO) — significant nuclear operations
- Chubu Electric Power Company
- Kyushu Electric Power Company — active nuclear restart program
- Tohoku Electric Power Company
Clean Energy Policy
National targets:
- 38% renewable electricity by 2030
- 40-50% renewables (including hydro) by 2040
- Carbon neutrality by 2050
- Government now emphasizes "maximum use of existing [nuclear] plants"
Policy framework:
- Feed-in Tariff (FIT) system since 2012
- Feed-in Premium (FIP) introduced 2022
- Nuclear restart policy — 14 reactors operating as of late 2024
- Non-Fossil Fuel Energy Certificate system
Utility Landscape
Japan's electricity sector includes a mix of former regional monopolies and new market entrants:
Regional Power Companies (General Electricity Utilities):
- Hokkaido Electric Power
- Tohoku Electric Power — operates Onagawa nuclear plant
- Tokyo Electric Power (TEPCO)
- Hokuriku Electric Power
- Chubu Electric Power
- Kansai Electric Power — operates Ōi, Takahama, Mihama nuclear plants
- Chugoku Electric Power — operates Shimane nuclear plant
- Shikoku Electric Power — operates Ikata nuclear plant
- Kyushu Electric Power — operates Genkai, Sendai nuclear plants
- Okinawa Electric Power
SSS-Eligible Resources
Nuclear Power
Japan has significant nuclear capacity that qualifies as SSS-eligible default clean energy:
| Plant | Utility | Capacity | Status |
|---|---|---|---|
| Ōi | Kansai Electric | 2,360 MW | Operating |
| Takahama | Kansai Electric | 3,392 MW | Operating |
| Mihama | Kansai Electric | 826 MW | Operating |
| Genkai | Kyushu Electric | 2,680 MW | Operating |
| Sendai | Kyushu Electric | 1,780 MW | Operating |
| Ikata | Shikoku Electric | 890 MW | Operating |
| Onagawa | Tohoku Electric | 825 MW | Operating |
| Shimane | Chugoku Electric | 820 MW | Resumed Dec 2024 |
Total operable capacity: ~31,679 MWe (World Nuclear Association, 2024) Nuclear generation (2024): 84,887 GWh
Hydropower
Japan has substantial conventional hydropower:
- Installed capacity: ~50 GW (including pumped storage)
- Conventional hydro: ~22 GW
- Major facilities: Primarily run-of-river and reservoir systems operated by regional utilities
SSS Classification
| Resource Type | SSS Eligibility | Notes |
|---|---|---|
| Operating nuclear | ✅ Clearly SSS | Pre-existing, no REC retirement |
| Legacy hydro (pre-FIT) | ✅ Clearly SSS | Default delivered, no certificate claims |
| FIT-certified renewables | ❌ Not SSS | RECs tracked separately |
| Non-Fossil Certificates | ⚠️ Gray area | Depends on tracking status |
EAC/REC Registry Infrastructure
Japan has multiple energy attribute tracking systems:
Primary systems:
- Non-Fossil Fuel Energy Certificates — National system for tracking non-fossil generation attributes
- J-Credits — Carbon credit system recognized by CDP and RE100 for renewable claims
- Green Power Certificates — Voluntary market certificates
International compatibility:
- I-RECs — Limited availability in Japan; primarily for international corporate claims
- APX TIGRs — Global registry option for some Japanese generators
Key considerations for SSS:
- Non-Fossil Certificates with tracking can document clean energy claims
- J-Credits are accepted for Scope 2 reporting by CDP and RE100
- Need to distinguish between certificates retired for RPS vs. available for SSS claims
Emissions Factors & Data Sources
Grid emission factors:
- National grid average: ~450-500 gCO2/kWh
- Varies significantly by regional utility (nuclear restarts lower regional factors)
Data sources:
- METI (Ministry of Economy, Trade and Industry) — Official energy statistics
- OCCTO — Transmission and generation data
- Japan Atomic Industrial Forum (JAIF) — Nuclear plant status
- ISEP (Institute for Sustainable Energy Policies) — Renewable energy tracking
Confidence Assessment
High confidence:
- Nuclear plant list and operating status
- Market structure and utility landscape
- Renewable targets and policy framework
Needs verification:
- Specific emission factors by utility
- Non-Fossil Certificate retirement rules for SSS eligibility
- Hydro capacity breakdown by utility
Missing:
- Utility-specific resource mixes for SSS pro-rata calculations
- Historical REC retirement data
- Supplier attestation pathways for Japanese utilities