Negative Price Probability · DE/LU

Why negative price probability forecasts are important

Negative prices change the economics of almost every short-term decision. Battery operators want to charge into negative hours and avoid discharging into them. Direct marketers of wind and solar use negative-price risk to decide curtailment, market timing, and how aggressively to bid. Industrial consumers and flexible loads treat negative hours as procurement opportunities. Asset optimizers allocate between day-ahead and later markets based on where the downside of oversupply is most likely.

A full probabilistic price distribution can imply this risk, but translating quantile forecasts into an actionable negative-hour signal adds friction and model risk. A dedicated probability product makes the decision explicit: for every quarter hour, you get a calibrated chance of a negative clearing price, without reconstructing it from another forecast.

Telescope Energy provides dedicated negative-price probability forecasts for every quarter hour in DE/LU for these use cases.

How our forecast works

Telescope Energy operates a collaborative forecasting platform. Our proprietary ensemble engine combines models developed by our research team with forecasts from independent expert forecasters. Contributing signals are continuously evaluated against realized auction outcomes, and the ensemble weights them by recent performance.

For this product, the ensemble output is mapped to a probability estimate for a negative day-ahead clearing price per quarter hour. Forecasts can be updated until gate closure and cover delivery through D+7. Delivery is through the Telescope API for integration into trading, storage optimization, and risk workflows. Complementary DE/LU day-ahead price forecasts are available on the same platform for users who need the full price path alongside the negative-price risk signal.

How to evaluate forecast quality

Forecast quality should be assessed against a defined benchmark over a representative evaluation window. The public preview lets prospective customers inspect released forecast values, while a pilot provides the appropriate setting to compare Telescope with a current provider or internal model.

For this product, an evaluation should include high-solar middays, strong wind periods, holiday demand troughs, and changing class frequencies. Relevant measures include Brier score, calibration by probability bucket, discrimination, and performance around operational decision thresholds. Results should be reported together with the benchmark, delivery horizon, data vintage, and evaluation period so that the comparison remains reproducible.

What are negative day-ahead prices in DE/LU?

Negative day-ahead prices occur when the auction clears below zero for a delivery period: generators effectively pay to produce, and consumers are paid to take power. In the DE/LU bidding zone this is no longer rare. High renewable feed-in, limited flexibility, and must-run generation regularly push the German market into negative territory, especially around midday solar peaks and strong wind overnight.

Negative prices are formed in the same daily auction as ordinary day-ahead prices, operated by nominated electricity market operators such as EPEX SPOT within the Single Day-Ahead Coupling (SDAC). Official price data for DE/LU is published by the Bundesnetzagentur on SMARD and on the ENTSO-E Transparency Platform.

A negative-price probability forecast answers a different question than a point or quantile price forecast: for each quarter hour, how likely is it that the auction clears below zero? That binary risk view is often what storage, demand flexibility, and renewable marketers need for operational decisions.

What drives negative price risk in Germany?

Negative prices are a residual-load story. When wind and solar feed-in approach or exceed demand, the auction has to clear low enough to induce curtailment, exports, storage charging, or demand response. Midday solar peaks, overnight wind surges, mild weekends, and holidays are classic setups. The steeper the renewable buildout, the more often these conditions appear.

Flexibility and interconnection decide how deep and how often prices go negative. Limited export capacity, inflexible must-run generation, and constrained storage amplify the risk; strong cross-border outflow and responsive demand dampen it. Fuel and carbon prices matter less at the zero threshold than the sheer volume of surplus renewable energy and the willingness of the bid stack to absorb it.

Forecasting negative-price probability therefore requires a joint view of load, renewables, and system flexibility, not just an extrapolation of recent prices. That multi-driver problem is what an ensemble of diverse, continuously benchmarked models is designed to handle.

Frequently asked questions

What does this forecast include?

The product provides a calibrated probability between zero and one for every quarter hour from D+1 through D+7.

How often is the forecast updated?

Probability forecasts can be updated until the day-ahead gate closure as the view of load, renewables, and system flexibility changes.

How is the forecast delivered?

Forecasts are delivered through the Telescope API for integration into trading, nomination, analytics, and asset-optimization workflows. Request a pilot to evaluate the product with your own benchmark and use case.