- Purpose:
- Hourly day-ahead price quantiles (10/50/90%) for the next day, the day after and days 3-7, per zone.
- Inputs:
- Recent prices, TSO load and wind/solar forecasts, weather forecasts, calendar, reservoir levels for hydro zones, and the known auction prices for day 2.
- Training:
- Histogram gradient-boosting quantile models (scikit-learn) retrained on a rolling window; the median corrected by half of its recent held-out miss per zone, hour and horizon (in a 2023-2026 walk-forward test this lowered the error by 1.4%); intervals calibrated with conformalised quantile regression.
- Evaluation:
- Walk-forward backtest since 2022 and the live frozen ledger, against persistence.
- Limits:
- Price spikes above recent history are underpredicted; regime changes need weeks of new data.