Posters

Abstract

The urgent need to carry out the energy transformation resulted in many countries in the planned dynamic development of wind energy. There is a lot of opposition due to the negative impact of turbines on avifauna. Is it possible to balance rapid increase of wind energy capacity with biodivercity protection? The solution can be provided by technological innovation in the form of detection-reaction systems. However, there is little published data on operation of such systems, which is causing a lot of doubt on their actual efficiency. We have analyzed the data from three detection-reaction systems installed on a wind farm in Central Spain. The specific feature of the system is that the cameras are in stereoscopic set up, enabling 3d location of bird, distance, altitude estimation and size classification. We used data recorded by the systems and data from on-site ornithological monitoring. The data for the analysis were detection data, videos and photos recorded by systems from July to June 2022. All recorded birds have been tagged to species, group of species by qualified ornithologists. The total number of bird detections collected by the systems was over 16,8 thousand. Majority of detections (ca. 10,3 thousand) were small birds (below 1,1 m of wing span). Within the rest of detections ca. 6 thousand detections concern raptors and over 5,1 thousand detections concern large raptors with wing span over 1,1m: vultures, eagles or kites, which are the of biggest concern as most subject to collisions with turbines. Over 3 thousand of detections concerned large birds recorded in the “risk sphere”, which is defined as an area within 300m from the turbine. In those cases the system responded with a turbine stop signal. Ca. 1,3 thousand of those detections were cases recorded during wind speed below 4m/s (no or minimal production). Just over 1,7 thousand detections were cases when the system gave the stop signal to the turbines during operation in order to minimize the risk of collision. That means ca. 1,5 of actual stop per turbine per day (amounting to on average of. ca. 5 minutes of turbine shutdown per day). Some 80% of stops occurred with wind speed between 4 and 8m/s, only 20% with wind above 8m/s. Additionally, each detection causing turbine stop was reviewed in search of potential false positives. The total number of false positives turbines stops was 261 (all 3 systems, which means less than 2% of all detections and ca. 0,25 of false positive turbine stop per system per day. Collected data allows to recommend using the system for protecting big raptors against collisions. Thanks to the ability to estimate distance and classify the size of bird the actual losses of energy production are minimal and below 1% of AEP. The analysis of recordings and photos didn't reveal any cases of bird collisions. Data from post construction monitoring (carcass search) confirm the lack of bird mortality under the turbines with the systems installed, hence the authorities agreed for further operation of turbines with those detection-reaction systems.