Japan Solar Update: No.163 (Aug 25 ~ 29, 2025)
Japan is gradually shaping a clearer picture of its future power supply as it moves toward 2050. At the 10th Meeting on Future Power Supply and Demand Scenarios held in June 2025, multiple model scenarios for electricity supply and demand in 2040 and 2050 were presented—highlighting key assumptions and outlooks for future energy planning.
<Key points>
- The Organization for Cross-regional Coordination of Transmission Operators (OCCTO) compiled a draft report from the Study Group on the Future Electricity Supply and Demand Scenarios, presenting multiple scenarios for the supply-demand balance in 2040 and 2050
- In the 2050 model scenarios, the electricity demand is assumed to range from 950 TWh to 1,250 TWh. Installed capacity assumptions include 45–90 GW of onsite PV system (at demand locations), 75–90 GW of commercial PV systems, 11 GW of onsite storage batteries (at demand locations), and 10–13 GW of grid-scale storage batteries
- Going forward, OCCTO will regularly monitor changes in assumptions and other factors, and plans to review the scenarios every three to five years
Draft report of the Study Group on the Future Electricity Supply and Demand Scenarios
Withe the aim of referring to the scenarios for facilitating the smooth implementation of long-term decarbonized power source auctions and other measures, and for advancing power source development in a planned manner, the scenarios are studied without necessarily presupposing consistency with the Strategic Energy Plan or other policies
Demand and Supply capacity were assumed within a certain range, and multiple scenarios for the supply-demand balance in 2040 and 2050 were presented
<List of components in the model scenarios>
| Model Scenario in 2040 | Model Scenario in 2050 | |||||
| Electricity Demand | 900 B kWh | 1100 B kWh | 950 B kWh | 1050 B kWh | 1150 B kWh | 1250 B kWh |
| Onsite PV (at demand locations) | 35GW | 70GW | 45GW | 60GW | 75Gw | 90GW |
| Commercial PV | 70GW | 85GW | 75GW | 80GW | 85GW | 90GW |
| Onshore Wind | 8GW | 13GW | 8GW | 10GW | 12.5GW | 14.5GW |
| Offshore Wine | 7.5GW | 22GW | 13GW | 18GW | 23GW | 28GW |
| Hydro | 23GW | 25GW | 22.5GW | 24GW | 25.5GW | 27GW |
| Biomass | 6GW | 9GW | 6GW | 7GW | 8GW | 9GW |
| Geothermal | 0.5GW | 1GW | 0.5GW | 1GW | 1GW | 1.5GW |
|
Onsite storage batteries (at demand locations) |
8GW | 8GW | 11GW | 11GW | 11GW | 11GW |
| Grid-scale storage batteries | 8GW | 10GW | 10GW | 11GW | 12GW | 13GW |
| Pumped storage | 20GW | 20GW | 20GW | 20GW | 20GW | 20GW |
| Nuclear power | 27GW | 33GW | Small: 23GW or Large: 37GW | |||
| Thermal Power |
Small: 96.9GW or Large: 135.8GW |
Small: 66.3GW or Large: 133.7GW |
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Following the formulation of these scenarios, the basic approach will be to regularly monitor changes in assumptions and other factors, review the scenarios every three to five years, and, if necessary, carry out earlier reviews
Figure 1 Outline of the draft report by the Study Group on the Future Electricity Supply and Demand Scenarios
Source: Materials of the 10th meeting of the Study Group on the Future Electricity Supply and Demand Scenarios (June 25, 2015), complied by RTS Corporation