Built for a changing market
As feed-in tariffs wind down and market-linked pricing expands, accurate JEPX spot price forecasts have become essential. We provide high-precision predictions where even ¥0.01 differences matter.
JEPX Prediction API
JEPX Spot Price Forecast API
AI-powered JEPX spot price forecasts across all 9 areas at 30-minute granularity. Includes a browser-based visualization GUI and CSV download, supporting trading decisions and battery dispatch optimization.
Visualization GUICSV downloadAll 9 areas30-min granularity¥0.01 slot prediction
What the API provides
Operations and analysis in one place
Beyond API integration, the visualization GUI lets you quickly check price trends in a browser — useful for both real-time decisions and planning simulations.
New features
Visualization GUI
View JEPX spot price forecasts as interactive charts directly in your browser. Ideal for pre-integration validation and daily price monitoring.
CSV download
Download forecast data in CSV format for analysis in Excel or internal tools. Start using the data immediately without any API integration.
AI-powered high-accuracy forecasts
All 9 areas covered
Individual price forecasts for all 9 JEPX areas, from Hokkaido to Kyushu.
30-minute granularity
Next-day forecasts at 30-minute intervals, providing the resolution needed for time-of-use trading and battery dispatch.
AI analysis of weather and supply-demand data
Our AI integrates weather forecasts, power supply-demand records, and historical market data to deliver high-accuracy price predictions.
¥0.01 slot prediction
A dedicated model predicts when JEPX spot prices will hit the floor price (¥0.01). For FIP generators, where premium payments do not apply during ¥0.01 slots, early detection enables supply shifting via battery storage to protect revenue.
| Target market | JEPX spot market |
|---|---|
| Output timing | Day-ahead at AM 7:00, AM 8:30, AM 11:30 |
| Output data | Spot market prices for delivery day and next day (96 slots total). The 11:30 output covers only the next day's 48 slots. |
| Coverage | Nationwide (excluding Okinawa) |
Typical use cases
Battery optimization (IRR improvement)
Optimize charge-discharge timing based on price forecasts to improve the IRR of battery investments.
Procurement cost optimization
Make forecast-driven decisions on procurement timing under market-linked pricing plans to reduce costs.
Trading strategy comparison
Back-test multiple trading strategies against forecast data to select the optimal approach.
FIP supply shifting
Use ¥0.01 slot predictions to charge batteries during low-price periods and discharge during high-price periods, maximizing revenue from renewable generation assets.
Integration picture
Instant browser access
Check forecast results immediately via the visualization GUI and download CSV files for internal analysis.
API-based system integration
Feed forecast values into operator dashboards or battery control logic via API, enabling automated decision-making.
Discuss your JEPX forecast use case
Start by exploring forecasts in your browser. We are happy to discuss API integration options as well.
Onboarding flow
01
Use-case review
Clarify how the forecast will be used and how it connects to existing systems.
02
API design
Define forecast items, refresh frequency, and delivery method.
03
Integration test
Validate connectivity and integrate the feed into business logic.
04
Production
Monitor usage and keep improving forecast operations over time.
Discuss your JEPX forecast use case
We can shape the delivery format around trading, simulation, or dispatch use cases.
Talk to us about the JEPX API