As the industry continues to expand, turbines take up increasing numbers of locations and sites in flat, simple environments — with high and steady wind velocities and low turbulence levels — are limited and crowded. The need for wind farms in a range of geographies is expected to grow over the next decade. But measuring the wind in areas of complex terrain is as complex as the land itself.
Complex terrain includes features such as hills, forests, obstacles and varying slopes and roughness. At these sites, wind is deflected over and around features; it does not follow a homogeneous linear path. This can lead to errors in lidar measurements.
Further complicating matters, turbulence and wind shear are higher in these locations, and wind conditions are harder to predict in general. Plus, modeling the wakes behind the turbines is substantially more complicated. Wind resource assessments (WRAs) are more uncertain than under ideal conditions in simpler terrain.
Farm development in these landscapes is difficult, especially with installation and operation of traditional met masts. These masts often require siting permits and frequently can't measure the full height of modern turbines without mathematical extrapolation.
This is all a headache. So, how can developers improve WRA techniques in such locations? There's an answer: lidar and advanced modeling technologies.
Because such terrain poses a unique measurement challenge, project owners and developers must account for non-homogeneous wind flow to have accurate, reliable and bankable data. Enter lidar in combination with modeling technologies.
Modeling technologies, such as flow complexity recognition (FCR) from Leosphere, a Vaisala company, and computational fluid dynamics (CFD), work with lidar sensors to ensure the best, most accurate and useable data — even when deploying measurement campaigns in very complex areas.
So, in simple-to-moderately tricky terrain, WindCube Complex Terrain Ready allows for accurate measurements thanks to the integrated FCR, a real-time, simplified and robust modeling tool. It accounts for the impact of moderate terrain complexity and provides a direct correction to the data. But at sites with even harder landscapes, CFD software is the best and most proven post-processing tool.
Through partnerships with CFD industry leaders and wind energy consultants, complex terrain experts can approve the corrected data, evaluate the resulting measurement uncertainty and ensure the WindCube data’s bankability. With these enhancements, wind farm developers, operators and turbine manufacturers can use WindCube’s data reliability and accuracy in all types of terrain.
While the wind industry’s expansion into hilly, mountainous and other areas presents a challenge in collecting trusted and precise wind measurements, lidar and new modeling tech make it possible.