Turbulent Wind Profiles in an Operational Power Tower Plant

Heliostats make up a significant portion of power tower plant costs but are currently designed using data from wind tunnel tests that cannot fully capture the real atmospheric flow encountered by operational concentrating solar power plants. Flow conditions are a crucial heliostat design input, as they determine the loads the heliostats will experience during their lifetime. This study presents the findings of a field measurement campaign conducted at the Crescent Dunes Solar Energy Project in Tonopah, Nevada, where a scanning Doppler lidar is used alongside meteorological masts to characterize the wind flow over the heliostat field. The results show a significant increase in wind shear over the field relative to surrounding desert, which is expected to affect the overturning moment on the heliostats. The modified flow persists downstream of the last heliostat row, then begins to dissipate gradually. Complex interactions between the heliostat field and atmospheric phenomena such as diurnal stability cycles yield unique observations (e.g., low-level jets, wakes, and large-scale turbulent structures) that cannot be reproduced in wind tunnels. These findings highlight the importance of field measurements for accurately characterizing the flow experienced by operational heliostats and assessing the resulting loads.