Column Vol.4 -Research on bird strike of wind power-


Hello, this is Takamatsu from Rera Tech. I'm in charge of a wide range of technical support, public relations, general affairs, and human resources.

The other day, we held an offline meeting workshop where all employees gather at Rera Tech. This was the first time I visited office. I was nervous in the real place, but I was able to feel the importance of meeting directly and communicating. From now on, we plan to carry out regularly.

By the way, the topic introduced this time is about "Research on bird strike (collision between windfarms and birds)".

Before the construction of windfarms, environmental assessments can reduce the impact on nature. The main measures are to avoid the construction of important birds in the habitat, and to devise windfarm positions and arrays. There are other measures related to windfarms, such as coloring and alert sounds. This time I checked the latter.

Among them, there were two very interesting research.

(1) Invision to paint wind power blades

Windmill Image1 The first study is to paint only one piece of blade of wind turbines of windfarm.1)

A study was conducted at Norwegian wind power plants to paint only one blade of four generators in 2013-2016.
As a result, it has been verified that the annual mortality rate of birds has decreased by about 70%compared to ordinary turbines.
In this study, the number of tests itself is small, and there are many unknown parts.2), Further research is expected in the future.










(2) Ingenuity to avoid the dangers of birds colliding with windmills by sound


The second is a study of using the sounds that birds dislike in 2020 at a wind power plant in northern Hokkaido.3)

The "way of painting the blade" introduced in the first research is effective in the daytime, but at night, the risk of birds collides with windmills due to the darker view. For this reason, this research was conducted mainly as a measure for night hours.

As a result of this verification experiment, about 80 % of the evasion behavior was confirmed. I hope these systems will be widely used and bird strikes will be reduced even a little.


The Ministry of the Environment said that from 2022 to 2023, as an environmental conservation measure based on the characteristics of offshore wind power, the purpose of continuous understanding of the environmental impact associated with operation is "corresponding management project in offshore wind power generation".4)We are implementing.

In this project, it seems that environmental conservation methods will be optimized by demonstrating methods that can reduce environmental impacts. We hope that the bird strike method will be demonstrated and optimized.


Bird strike is an issue in a natural environment that cannot be separated even if it is cut in wind power. We hope that various research will continue to progress, and better measures will be implemented to reduce the impact on the natural environment.


Image 3


Bar Image


As a wind -up consultant, Relatech will conduct an optimal air -based survey using "observation" and "estimation" for wind power. Please feel free to contact us if you have any consultation on the style.

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Reference material

  1. Roel May, Torgeir Nygård, Ulla Falkdalen, Jens Åström, Øyvind Hamre, Bård G. Stokke, “Paint it black: Efficacy of increased wind turbine rotor blade visibility to reduce avian fatalities”, Ecology and Evolution, Volume10, Issue16
    https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.6592
  2. Wind Turbines Kill Birds. This Incredible Simple Trick Has Saved Them.
    https://www.popularmechanics.com/science/a33809700/wind-turbine-blades-bird-deaths-down/
  3. Examination of bird strike measures in wind power generation facilities
    https://www.ideacon.co.jp/technology/inet/news_file/file/vol59_new01s.pdf
  4. Optimization and demonstration of environmental conservation methods to promote the introduction of offshore wind power generation
    https://www.env.go.jp/content/900470632.pdf