This presentation summarizes the results of a collaborative atmospheric study with contributions from Steven Clark (NRG Systems), Catherine Meissner (WindSim), Pau Casso (Vortex), and Gibson Kersting (E.ON Climate & Renewables North America Inc.). Field data was mined and supplied by NRG Systems, E.ON, and Windsim. Measurement analysis was performed by Windsim and NRG Systems. And numerical modeling and analysis was performed by Windsim and Vortex.
Atmospheric stability is an important metric in the wind industry. Atmospheric stability is a non-standardized input into CFD simulation codes. Today, all CFD codes incorporate their own, frequently differing, method of accounting for atmospheric stability effects. In Wind Resource Assessment (WRA), it is still uncommon to measure atmospheric stability. This work analyzes the state-of-the-art methods for calculating atmospheric stability. Based on the methods reviewed and analyzed, we will recommend best practices for calculating thermal effects using standard wind resource assessment sensors and optimum tower set-up. We will discuss how measured and mesoscale modeled atmospheric stability parameters and mean wind speed profiles should be incorporated into CFD simulations to deliver added value for the wind resource assessment.