Germany runs the largest onshore wind fleet in Europe, around 68 GW spread across more than 28,000 turbines, from the North Sea coast down to Bavaria. OpenWindCast publishes an independent forecast of German onshore wind output for tomorrow and scores it, every day, against the forecast the four German transmission system operators publish themselves.
Averages across all zones. Every number on this page is recomputed daily from the public record below.
Great Britain has one of the largest onshore wind fleets in Europe, with most capacity in Scotland. The forecast covers GB onshore wind and is scored against NESO's own forecast, published through Elexon.
Every forecast ships with an 80% interval. This shows how often the actual output landed inside it, and how wide it was.
The German fleet is both very large and very widely spread, with the heaviest concentrations in Schleswig-Holstein, Lower Saxony, Brandenburg and Saxony-Anhalt. Scale of that kind changes the forecasting problem. In a fleet spanning most of a continent-sized country, a weather system that arrives late over one region is often early over another, and those differences partly cancel in the national total. This is why large, dispersed fleets tend to show lower forecast error as a share of capacity than small ones, and it is a property of the fleet rather than of any particular forecaster.
The benchmark is the day-ahead onshore wind forecast published by Germany's four transmission system operators, 50Hertz, Amprion, TenneT and TransnetBW, aggregated for the DE-LU bidding zone and distributed through the ENTSO-E Transparency Platform. It is captured on the day it is published and then held fixed, so the comparison is always against what the market could actually see before the auction closed.
One value per day: onshore wind output at 11:00 local time tomorrow, expressed as a load factor and published before 12:00 local, ahead of the day-ahead auction rather than after it. Once the German TSOs' own forecast for that day is published it is captured and held fixed, and once the metered output is settled both forecasts are scored against it. Every day is added to the record below and nothing is removed or rewritten later, so the full history is there to be checked rather than summarised. How this is measured.
No. SMARD republishes the German transmission system operators' own forecast. That published forecast is the benchmark OpenWindCast is measured against. OpenWindCast produces a separate, independent forecast, and the two are scored side by side every day.
No. This zone covers German onshore wind only.
Compare every zone: how accurate are European TSO wind forecasts?
Mean absolute error as a percentage of installed capacity. Lower is better.
The share of days the forecast lands closer to the metered output than the operator's own forecast.
The range the actual output should land in 80% of the time, recalibrated daily.
NESO's published day-ahead 11:00 forecast, a fixed yardstick that is never used as an input.
A forecast of wind generation for the next delivery day, issued before the day-ahead electricity auction closes at 12:00 CET. Market participants use it to decide how much wind energy to bid into the auction.
One value per zone per day: the onshore wind output at 11:00 local time on the next day, expressed as a load factor and converted to megawatts with the installed capacity the grid operator publishes. Every forecast is published in the morning, before 12:00 local time.
Each day, the absolute error of the OpenWindCast forecast and of the grid operator's own day-ahead forecast are compared on the same 11:00 target. The site reports the mean absolute error as a share of installed capacity (nMAE), the win rate, and, where official prices are available, the imbalance cost of bidding each forecast.
Benchmark forecasts, metered generation and installed capacity come from the grid operators: Energinet, Elia, Fingrid, Red Eléctrica, the four German TSOs, PSE, REN, NESO via Elexon, and EirGrid with SONI, mostly through the ENTSO-E Transparency Platform. Weather inputs come from Open-Meteo.
Yes. The dashboard and the daily verification record are public, and each zone's history can be downloaded as CSV from the forecast section. For anything else, email m.sahaf@live.com.