Improving 15-minute power price forecasting with sawtooth correction

At Kpler, we’re committed to continuously improving the accuracy and reliability of our Power forecasts. On 14 November, we introduced an important enhancement to our 15-minute day-ahead price model in order to address a new ‘sawtooth’ pattern that has emerged. This new sawtooth correction methodology better captures 15 minute price dynamics and improves short-term forecast accuracy across European bidding zones.

Why we introduced the sawtooth correction

In recent months, many power markets have exhibited a recurring intra-hour price pattern commonly referred to as a “sawtooth” shape—rapid, alternating up-and-down price movements that can be difficult for traditional models to capture.

To address this, our team designed a new correction layer that learns this behavior directly from market data and applies it on top of our existing forecast. The goal was simple:
Improve 15-minute precision without altering hourly forecast performance or introducing unnecessary model bias.

How the new correction works

The sawtooth correction is a lightweight, adaptive layer applied to our previous price model:

It learns a correction signal on short rolling windows, ensuring rapid adjustment as market behavior evolves. The corrector is applied on top of previously existing forecast (in blue) in order to create a new forecast (red)

• When sawtooth patterns fade, the correction naturally winds down, preventing overfitting.
  
  
• The correction intensity varies by bidding zone, depending on how strong or modelable the pattern is. In zones like Denmark, only a small adjustment is applied as in the chart below.

• Crucially, hourly forecasts remain unchanged, ensuring consistency with users’ strategic workflows.
  
  

The result is a cleaner, more precise 15-minute forecast that remains faithful to underlying hourly market structure.

Demonstrated performance improvements

We re-evaluated model performance using October 2025 data, recomputing metrics and comparing results before and after the correction.

Here is what we have observed:

✔️ Lower 15-minute mean average error

The new model reduces 15-minute MAE across all bidding zones, strengthening the accuracy of intraday trading and operational decisions.

✔️ No bias introduced

Hourly averages remain fully aligned with the previous model, confirming that the correction improves shape precision without shifting overall price levels. 

✔️ Conservative, reliable behaviour

Isolating the correction (ie, the delta of the new model compared to the previous one), we can compute performance metrics that compare this newly applied correction to the optimal correction that we could have applied. The “optimal” correction is defined as the correction that should be applied to our existing model, after having shifted our existing model up/down to match the hourly average of the day-ahead actual at each hour.

• The corrector avoids over-correction.

What this means for Kpler users

This enhancement strengthens Kpler’s position as the leading provider of transparent, high-resolution power market intelligence. With the sawtooth correction now fully integrated Kpler users now benefit from:

• Higher forecast accuracy in 15-minute granularity.
• More stable, reliable performance day-to-day, especially in markets prone to sawtooth price behaviour.
• No disruptions or changes to the hourly forecasts.
  
  

We’re excited to continue building features that help power market participants navigate complexity with confidence.

Don’t have access? Reach out for a demonstration with one of our experts.