The Impact of the Wind Power Plant on the Air Radars Functioning

Abstract

Nowadays a large interest in the public and private sector is dedicated in generating electricity using renewable resources. Thus, over 60,000 MW is produced worldwide by using the wind energy. These systems are generally composed of power plants formed from 2–3 to several tens, hundreds of wind turbines with rotating blades that reach heights over 160m. The number, the height, and the rotation of these wind turbines represent technical challenges for the radar system efficiency and accuracy. They should be assessed carefully, in each case, to ensure that it maintains an acceptable level of the air space surveillance capability. The research paper presents the influence of the wind power farms on the air radars especially in cases of surveillance area, both for the primary radars and the secondary radars. There are differences between the interference between the wind turbines and radars functioning, depending on the types of radars. In the last decades in Romania is a permanent effort to increase the number the wind farms built, or in the process of being built, but also referring at the number of wind turbines in these parks and their physical dimensions. This paper focuses on the effects of the wind farms on the radars efficiency, and their potential impact on the ability of airspace surveillance. This results in a concise and transparent reference guide for developers of wind farms when assessing the impact of wind turbines on aerial surveillance systems. Specialists are relatively unanimous in their opinion that, in order to make an assessment of the impact of the wind farms on the radars must be defined at least three areas corresponding to different levels of the technical expertise. They must be combined with the influence of the wind farms on the ability of the radar to fulfill the mission, why they were installed, assuming that it is necessary to create an exclusive protection area. First, are discussed briefly the principles of the radar’s operation, depending on their type: primary and secondary surveillance radars. Further, are estimated the induced reflections by the wind power plant on the radar system. If the number of false targets generated by the reflections from wind turbines is too big, so it exceeds the processing capacity of the radar, the operational capacity will suffer. There are presented some theoretical aspects, followed by some cases where the proper functioning of the primary and secondary radars is affected. The model is tested in field, at two different distances, with airplanes and helicopter flying at different altitudes, with radar placed near the wind power plant Fantanele – Cogelac, the biggest in Romania. Finally, is estimated the area necessary to assure proper functioning of radars. Some conclusions and references are presented.