OF WIND TURBINES ON RADAR SYSTEMS AND MITIGATION MEASURES: THE CASE OF NGONG WIND FARM IN KENYA

Abstract

Air traffic control radar system that monitors traffic in Nairobi, Kenya and its environs is susceptible to display clutter and false targets due to Doppler Effect caused by rotating wind turbine blades along the aviation pathways. This study aims to address the influence of wind turbines on aviation radar system along Ngong Hills. The import of the study lies in the potential increase of wind parks along the aviation pathways of Ngong and their influence on radar systems. The methodology adopted in determination of this influence of these wind parks was by executing ArcGIS Viewshed analysis tool. The input data used was a 60 meter digital elevation model of Kenya obtained from World Resources Institute. This data was re-sampled to 6 meters DEM in order to obtain the precision of higher resolution near the wind turbines. Line of sight analysis was carried out using the LoS tool in ArcGIS to determine the visibility of objects over the surface. The results indicate that all turbines are visible to the radar but not detected due to the distance between the radar and turbines. A map indicating wind power density and radar coverage was also generated showing optimal wind farm setup sites. Based on this, operator guidance for radar system setup, optimal site for setting up turbines and observed displayed effects on radar screens were identified and recommended. Also it’s now easy to determine visibility of all wind turbines around Ngong Hills to the JKIA radar.