Multi-lidar wind resource mapping in complex terrain

Abstract

Scanning Doppler lidars have great potential for reducing uncertainty of wind resource estimation in complex terrain. Due to their scanning capabilities, they can measure at multiple locations over large areas. We demonstrate this ability using dual-Doppler lidar measurements of flow over two parallel ridges. The data have been collected using two pairs of long-range WindScanner systems operated in a dual-Doppler mode during the Perdigão 2017 measurement campaign. The lidars mapped the flow along the southwest and northeast ridges 80 m above ground level. By nalyzing the collected data, we found that for different flow nditions on average wind speeds are 10% higher over the outhwest ridge compared to the northeast ridge. At the southwest ridge, the data shows, depending on the atmospheric conditions, a change of 20% in wind speed along the ridge. For the measurement period, we have simulated the flow over the site using WRF-LES to compare how well the model can capture wind resources along the ridges. We used two model configurations. In the first configuration, surface drag is based purely on aerodynamic roughness whereas in the second configuration forest canopy drag is also considered.