The risk of birds colliding with wind turbine blades is sometimes used as an argument against the use of wind power. Seabirds deliberately avoid wind turbine rotor blades offshore, that is the main finding of a new study that mapped the flightpaths of thousands of birds around wind turbines in the North Sea. Most importantly, during two years of monitoring using cameras and radar, not a single bird was recorded colliding with a rotor blade. The movements of herring gulls, gannets, kittiwakes, great black-backed gulls at the Aberdeen Offshore Wind Farm were studied in detail from April to October when bird activity is at its height. The results show that birds’ patterns of movement adapt to rotor blades from approximately 120m and become increasingly precisely adapted the closer the birds come to the rotors. There were also some variations between the seabirds studied. The herring gulls and kittiwakes showed horizontal avoidance further away from rotor blades, 90–110m and 140–160m respectively, while the gannets and great black-backed gulls only exhibited avoidance behaviour at 40m and 50m from the tips of rotor blades.During the study, not a single collision between a bird and a rotor blade was recorded, even though birds are at risk of coming into contact with turbine blades.The unique, previously unused, technical solution for the study has been to combine radar data with cameras to identify the species of seabird and create a three-dimensional image of birds’ flight patterns and how they avoid rotor blades. Collision risk modelling to date has, according to Cox, used static model inputs and basic assumptions. The new study has been able to focus in more detail on individual birds’ flight behaviour. The project was also conducted over a significant period of time to make it as accurate as possible. As with most studies, there are several new directions that these findings open. Cox believes that the model using a combination of radar and cameras could set a new standard for collision risk calculations and says that there is still a large amount of data to analyse.
The risk of birds colliding with wind turbine blades is sometimes used as an argument against the use of wind power. Seabirds deliberately avoid wind turbine rotor blades offshore, that is the main finding of a new study that mapped the flightpaths of thousands of birds around wind turbines in the North Sea. Most importantly, during two years of monitoring using cameras and radar, not a single bird was recorded colliding with a rotor blade. The movements of herring gulls, gannets, kittiwakes, great black-backed gulls at the Aberdeen Offshore Wind Farm were studied in detail from April to October when bird activity is at its height. The results show that birds’ patterns of movement adapt to rotor blades from approximately 120m and become increasingly precisely adapted the closer the birds come to the rotors. There were also some variations between the seabirds studied. The herring gulls and kittiwakes showed horizontal avoidance further away from rotor blades, 90–110m and 140–160m respectively, while the gannets and great black-backed gulls only exhibited avoidance behaviour at 40m and 50m from the tips of rotor blades.During the study, not a single collision between a bird and a rotor blade was recorded, even though birds are at risk of coming into contact with turbine blades.The unique, previously unused, technical solution for the study has been to combine radar data with cameras to identify the species of seabird and create a three-dimensional image of birds’ flight patterns and how they avoid rotor blades. Collision risk modelling to date has, according to Cox, used static model inputs and basic assumptions. The new study has been able to focus in more detail on individual birds’ flight behaviour. The project was also conducted over a significant period of time to make it as accurate as possible. As with most studies, there are several new directions that these findings open. Cox believes that the model using a combination of radar and cameras could set a new standard for collision risk calculations and says that there is still a large amount of data to analyse.
