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​Wind Power Icing Atlas – WIceAtlas

Wind power has a central role in climate change mitigation and large amounts of new wind power are needed to meet COP21 global climate goals. In order to explore feasible areas for building new wind farms, wind maps are widely used in the wind industry for preliminary resource assessment. However, other information on climatological challenges, such as meteorological icing or icing maps, are typically missing from public data sources. This is why the Wind Power Icing Atlas (WIceAtlas) was created: to provide information on in-cloud icing severities worldwide.

In icing conditions, expected long-term production losses due to wind turbine blade icing remains today as one of the largest sources of risk and uncertainty in project financial estimates for example in Scandinavia, Canada and other high altitude locations in cold climate sites. Iced rotor production losses can lead to much larger interannual production fluctuations than typical annual wind speed variations. These common cold climate challenges need to be investigated in the site assessment phase (before any large site installations) in order to better plan for risk mitigation procedures and the appropriate technological solutions to assure a solid business case in cold climates.

What is WIceAtlas?

The core of WIceAtlas consists of over 4000 meteorological stations globally with +20 years of measurement and observation data for evaluating the upcoming 20 years of wind power (and other tall structure) icing severities. By analysing extensive historical icing weather conditions, it is possible e.g. to estimate the resulting long-term iced turbine production losses thus giving valuable Annual Energy Production (AEP) estimates for financial calculations. In WIceAtlas, icing severity is defined as icing frequency (% of time) resulting from in-cloud icing.

The public WIceAtlas map uses cloud base height and temperature < 0°C as a proxy for in-cloud icing conditions from the >4000 meteorological stations and interpolates between stations icing conditions to 150 meters above ground level to create icing frequencies for large geographical areas.


The objectives of the publically available WIceAtlas are to

  • Provide information and increase awareness of icing severities for wind power purposes regarding expected production losses, ice throw risks assessments and turbine lifetime
  • Help design pre-construction resource assessment instrumentation and pre-selection of appropriate turbine model and type
  • Provide information for other tall structures about icing severities

Customer offering

In addition to the above publically available material, VTT also offers to four different phases in the overall project development phase more detailed analysis for IEA Ice Classes 1,2,3,4 and 5 such as:


  1. Region feasibility
  2. Site feasibility/ selection project
  3. Site assessment
  4. Operational assessment

Here is an example of interannual and –monthly variation of site specific icing frequencies:

Interannual_and_monthly_variation.pngExample of wind farm icing map. Public version on left hand side and detailed version on right hand side.



For the more detailed analysis, please contact VTT.


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