Hydropower forecasting
Hydropower output depends less on tomorrow's weather than on the water already in the river or reservoir, and on how the plant is operated. Frontwatt forecasts it from recent production, rainfall and the plant's announced availability, and keeps the uncertainty visible.
Updated
Why hydro is different
- Water arrives with a delay. Rain over the catchment reaches a run-of-river plant hours or days later, so recent output is the strongest signal for tomorrow.
- Operation decides. Reservoir plants are dispatched by their operators. Canal plants follow irrigation schedules set by the water authority. A plant can stop for reasons no weather model can see.
- Every plant is its own case. The type of plant decides the method, not a one-size model.
How Frontwatt forecasts a hydro plant
- Recent output. The latest metered production, hour by hour, is the baseline.
- Rainfall. Precipitation scenarios for the coming days move the baseline up or down compared with what is normal for the season.
- Water routing. A simple reservoir model spreads incoming water over the following days, so a wet day raises output gradually rather than all at once.
- Plans and declared availability. Operating plans you share are applied as limits. In Türkiye, where a plant’s declared available capacity, the EAK published by EPİAŞ, signals a shutdown, as with a canal plant at the end of the irrigation season, the forecast follows it.
- Uncertainty from history. The ranges come from how much this plant’s output has actually changed from one day to the next.
Why we keep it simple: for hydro, a well-built rule based on recent output and announced availability is hard to beat. We switch a hydro plant to a machine-learning model only when that model beats the rule on locked test periods. How models earn their place.
Methods by plant type
| Plant type | Main signal | What changes the forecast |
|---|---|---|
| Run-of-river | Recent output | Rainfall over the coming days |
| Canal | Irrigation schedule | Season start and end, declared availability |
| Reservoir | Operator’s dispatch plan | Plans you share |
What you need to provide
- Plant type, installed capacity and units.
- Hourly metered output. In Türkiye, EPİAŞ publishes it for licensed plants.
- Planned outages and, for reservoir plants, operating plans when you have them.
What you get
- Hourly ranges and the median for the rest of today, tomorrow and the day after.
- The day-ahead schedule with the lowest expected imbalance cost.
- Daily accuracy scorecards, with days when the plant is shut for the season reported separately rather than counted as easy wins.