Passive radar technology for environmentally friendly wind turbines

Increasing the efficiency and ecological compatibility of wind turbines is a key issue in the field of renewable energies. One particularly important aspect is the so-called needs-based night-time labelling, which is intended, among other things, to counteract light pollution and prevent potential collisions between flying objects and wind turbines. It is intended to minimise the flashing of wind turbines at night.

The passive radar system ‘PARASOL’, developed by PARASOL GmbH & Co. KG in collaboration with the Fraunhofer Institute for High Frequency Physics and Radar Technology, has recently taken a decisive step forward. In a research project funded by the German Federal Environmental Foundation (DBU), new algorithms and technological advancements were implemented that significantly improve the accuracy and range of the system and thus further increase the safety and efficiency of wind turbines. This made it possible to create a prototype that for the first time combines environmental protection issues with needs-based night-time identification of wind turbines using passive radar. As a funding consultant, EurA Kiel secured the crucial funding for the development of the innovation.

Previous challenge: false alarms during detection at close range

As part of the project, detection clusters at close range of the passive radar system were analysed and weaknesses in the detection of small flying objects, such as birds, were identified. The causes of the detection clusters were precisely determined. Various criteria and techniques such as normalised acceleration, sign classification and transformations in the frequency domain using Fast Fourier Transform (FFT) were used to classify flying objects and suppress erroneous signal clusters. 

Improved detection range and signal processing

Another focus of the project was to improve the detection range of the PARASOL system. The system uses advanced AI-supported signal processing techniques to increase the sensitivity of the receiver and optimise the performance of the antenna technology. By utilising non-coherent and coherent integration, a significant improvement in the sensitivity of the system has been achieved. This technological advancement has enabled PARASOL to successfully detect small flying objects such as birds. In tests carried out near wind turbines on the Moselle near Koblenz, the passive radar system was able to detect formations of ducks, Canada geese, swans and even cormorants. This represents an important advance in terms of nature conservation, as specific flight activities of birds in the vicinity can now be monitored and the operation of wind turbines can be controlled.

Looking to the future: the right AI approach to signal processing

The PARASOL project has made important progress towards a robust and functional solution for the night-time labelling of wind turbines. A downstream project by PARASOL GmbH & Co. KG plans to test and further optimise the prototypes and algorithms developed in a wind farm under real conditions. A key topic in the future will be the further development of AI-supported signal processing. Choosing the right AI approach will therefore form the basis for further development in order to extract the necessary data and make precise decisions. The use of AI could not only improve the efficiency of detection, but also reduce the costs of implementing and maintaining the system, which also makes the project attractive from an economic point of view..

The long-term goal is to create an effective and ecologically sustainable solution that fulfils both the requirements of nature conservation and the regulatory requirements for demand labelling. A successful practical test of the system could not only help to improve the safety of birds in the vicinity of wind turbines, but also make an important contribution to the acceptance of wind turbines. If the passive radar system ‘PARASOL’ is successfully implemented in practice, it could serve as a model for the wind power industry worldwide and at the same time set new standards for nature conservation and environmental technology.

The passive radar system protects small flying objects such as birds from collisions with wind turbines.

Conclusion

The further development of the passive radar system ‘PARASOL’ impressively demonstrates how modern technologies can contribute to solving complex challenges in the field of renewable energies. With innovative algorithms, improved signal processing and the targeted use of artificial intelligence, it has been possible to optimise the detection of small flying objects such as birds and extend the range of the system. The results of the project offer promising approaches for an environmentally friendly, economically viable and technically mature solution for the needs-based night-time identification of wind turbines - a significant step towards a greener future.

Please feel free to contact us: Our expert Dr Viktor Schneider is available at any time to talk to you about passive radar technology and renewable energies.

Text: Britta Rückriem

Header image, category images left, centre and right: PARASOL