Ice build-up on wind turbine blades and resulting production losses is a phenomenon that happens every winter in the Nordics: sometimes more and sometimes less. Icing losses have been reported on the news in Finland frequently in November and December 2022. For this reason, we decided to see if we see severe icing events from our own operational met mast measurements and in-house icing weather model.

Finnish transmission system operator Fingrid produces real-time wind energy production and forecasts online. As can be seen in figure below, there has been large differences between measured and forecasted production which has been reported as icing on the news. During November 2022, we have measured icing events on four operational 174 m high met masts around Finland so we can confirm that several icing events have occurred during November.

By comparing our met mast measurement and in-house icing model results with Fingrid measured and forecasted wind energy production in Finland, we confirm four large-scale icing events over Finland impacting almost all Finnish wind farms simultaneously.

Here is a video of our in-house icing forecasts for all of November showing several large-scale icing events over large areas of Finland and other parts of Nordics.

By adding a simple icing loss forecast model (IceLossForecast1.0) from one wind farm position in Finland to the Fingrid forecasts, we are able to reduce the forecast error by 15 % for November. This is a highly simplistic method is used for illustration only. Our estimate is that wintertime forecast errors during icing conditions can be lowered even more by our IceLossForecast model if it is implemented project specifically on all Finnish wind farms to capture local weather events even better. In our latest conference presentation at WinterWind 2022, we have also demonstrated the benefits of icing loss forecasts for wind farms by further increasing icing loss forecasting accuracy by calibrating the model with measured turbine production data.

Blade heating technology can help in lowering the icing losses and such ice protection systems (IPS) are offered by some wind turbine manufacturers and 3rd party providers.

As a summary, there is a big potential to improve the accuracy of wind energy forecasts in Finland and in all of Nordics by implementing a state-of-the-art icing loss model.

For more information, please contact or