{"id":30383,"date":"2026-07-02T12:59:40","date_gmt":"2026-07-02T10:59:40","guid":{"rendered":"https:\/\/cubeconcepts.de\/?p=30383"},"modified":"2026-07-02T13:17:34","modified_gmt":"2026-07-02T11:17:34","slug":"weather-forecast-energy-market-bess","status":"publish","type":"post","link":"https:\/\/cubeconcepts.de\/en\/wettervorhersage-energiemarkt-bess\/","title":{"rendered":"Weather Forecasts & the Energy Market: Why Accurate Forecasts Are Crucial"},"content":{"rendered":"

Today, the German electricity market is tied to the weather like hardly any other economic sector. With renewable energies accounting for nearly 60 percent of total generation, it is no longer primarily demand that determines the electricity price, but rather the question: Is the sun shining, is the wind blowing\u2014and how accurately can that be predicted?<\/p>\n\n\n\n

While the Weather forecast<\/strong> formerly for the Energy market<\/strong> was once just a side note, today it is one of the most important pieces of information for all stakeholders in electricity trading. An independent and highly specialized market has emerged for precise and regionally resolved weather forecasts. They are considered a critical input factor for grid control, the power exchange, and the economic operation of Battery storage<\/a> BESS.<\/p>\n\n\n\n

Three target groups and different requirements for weather data<\/h2>\n\n\n\n

Grid operators: schedules, balancing energy, and redispatch<\/h3>\n\n\n\n

Transmission and distribution system operators need weather forecasts to plan power plant dispatch and grid utilization. If the actual feed-in from wind and PV deviates from the forecast, grid bottlenecks are looming<\/strong> \u2013 the result is redispatch measures, meaning short-term interventions in the operating mode of power plants and generation facilities.<\/p>\n\n\n\n

The dimension of this problem is shown in current figures: provisional costs for grid bottleneck management rose by four percent in 2025 to around 3.1 billion euros<\/strong>, although the total volume of the measures remained almost unchanged at around 30.3 terawatt-hours.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Particularly noteworthy: In 2025, photovoltaic systems had to be curtailed by 94 percent more than in the previous year \u2013 a direct effect of increasingly precise, but also increasingly volatile PV feed-in, which pushes the distribution grid to its limits on sunny days. For grid operators, weather forecasting is therefore not just a nice-to-have for planning, but has a direct impact on costs.<\/p>\n\n\n\n

Further information: Redispatch \u2013 Technology, Processes & Future<\/a><\/em><\/p>\n\n\n\n

Electricity trader: Price forecast for day-ahead and intraday<\/h2>\n\n\n\n

For market participants in power trading, the weather forecast is the basis of every price assessment. Since wind and PV feed-in directly influence the merit order, the prediction accuracy<\/strong> about Profit or loss<\/strong> in day-ahead and intraday trading.<\/p>\n\n\n\n

The resulting volatility is now extreme: EPEX prices reached in 2025<\/strong> a span from \u2013130 to +583 \u20ac\/MWh<\/strong>. In the first half of 2026<\/strong> were they even prices from \u2013 499 to + 747 \u20ac\/MWh<\/strong>. The number of hours with negative electricity prices was around 457 in 2024 and 573 in 2025, with a continued upward trend.<\/p>\n\n\n\n

\"Negative-power-prices-2025-chart\"<\/figure>\n\n\n\n

At the same time, the average intraday spread grew from 6 ct\/kWh (2020) to 11.7 ct\/kWh (2025), with a forecast of 15\u201320 ct\/kWh by 2030. Anyone who knows regional cloud cover or a local lull in the wind hours earlier and more accurately than the market can trade these price spikes specifically\u2014those who cannot, pay for them.<\/p>\n\n\n\n

BESS operators: schedules, arbitrage, and multi-use control<\/h2>\n\n\n\n

For battery energy storage system operators, both issues converge into a core business question: when to charge, when to discharge? Schedule optimization of a BESS in front-of-the-meter (FTM) operation depends directly on the accuracy of the price forecast and thus the weather forecast \u2013 every missed price peak is lost arbitrage<\/strong>, every poorly timed charge is a real economic loss.<\/strong><\/p>\n\n\n\n

This applies all the more the more granular the revenue strategy is: A storage system that engages in revenue stacking \u2013 meaning multiple revenue sources such as Day-Ahead Trading<\/a>, Intraday Trading<\/a> and Control energy<\/a> combined \u2013 requires precise, short-term weather data for every single decision-making level.<\/p>\n\n\n\n

From prediction to roadmap \u2013 briefly explained<\/h2>\n\n\n\n

Weather services and specialized energy meteorology providers create their forecasts on the basis of numerical weather prediction (NWP) models, which are calculated multiple times using ensemble methods with slightly varied initial conditions in order to depict a range of possible developments. For the energy market, the decisive factor is less the model itself than the regional resolution<\/strong>A nationwide average forecast says little about whether a lull in the wind will set in above a specific wind farm in Schleswig-Holstein in two hours. The finer the spatial and temporal resolution, the more tradable the information becomes\u2014and the more expensive it is to procure.<\/p>\n\n\n\n

Aggregators as intensive users of weather data<\/h2>\n\n\n\n

How seriously the industry takes the issue is evident in Flexibility aggregators<\/strong>, who coordinate BESS portfolios in FTM operation. For them, investing in the most precise, high-resolution weather data possible is not an IT cost item, but rather a direct revenue driver<\/strong>. Every additional bit of accuracy in short-term forecasting improves schedule optimization across the entire coordinated portfolio and multiplies with the number of controlled assets.<\/p>\n\n\n\n

aggregators managing large, cross-border storage portfolios, such as the partners of CUBE CONCEPTS Second Foundation<\/strong> or Inspired<\/strong>, thereby ranking among the market participants with the highest economic interest in forecast quality of all. Therefore, they work closely with meteorological research institutes, commercial weather services, and climate tech companies, actively supporting their work. <\/p>\n\n\n\n

Extreme weather as a stress test for the energy market<\/h2>\n\n\n\n

We have already described in detail in separate articles how strongly individual weather conditions can disrupt the market balance:<\/p>\n\n\n\n