IceRisk – Ice throw risk assessment

IceRisk is a state-of-the-art ice throw risk assessment product used for mapping the risk caused by ice throw in wind farms. The IceRisk tool has been extensively validated with multiple ice throw observation campaigns and we have performed more than 50 wind farm assessments since 2013.

Ice throw modeling

The IceRisk assessment methodology follows the relevant international standards and guidelines (IEA Wind Task 19) for ice throw assessments. The methods and results are presented in a comprehensive report following ISO 31000 – Risk management.

The following tasks are coved in our IceRisk assessments:

• Icing and wind climate at the wind farm using in-house weather models,
• Ice piece throw trajectory calculations for the particular turbine type,
• Statistical landing positions scaled for each turbine in the wind farm,
• Terrain influence for each turbine in the wind farm.

Mapping the risk of ice throw

The IceRisk results are presented as probability maps, similar to the image below.

Example of ice throw probability map. A hiking trail is shown as a dashed red line.

The risk values in the map are general LIRA-values, which is a common way to describe the risk for a person at a given location. Below is an example of common risk criteria (LIRA) for different activities and objects.

Acceptable common risk criteria (source: Kjeller Vindteknikk/IEA Wind Task 19).

Detailed risk evaluation

In addition to mapping and presenting the risk, a detailed evaluation is performed on how people or critical infrastructure are present at the wind farm area. Typical examples are that a road is passing nearby or a public ski track or hiking trail exists near the wind turbines (See dashed red line in Figure 1 as example). In such cases, we can calculate an individual and detailed risk assessment (IRPA-values) connected to the certain activity.

In addition to safety risk assessments, we can also provide detailed cost-benefit analyses to optimize combined wind and solar power plants.

Recommended mitigation measures

Based on the risk assessment results, mitigation measures are suggested to meet local and international risk acceptance criteria. These mitigation measures are based on the combined risk, the activities in certain area and knowledge on how to reduce risk by cost efficient methods.