Wind Resource Grids

Wind Resource Grid (WRG) datasets are useful if you plan to site met towers, design layouts, or obtain estimates of wind energy. Available in 50- and 200 m resolution, WRG datasets are compatible with all leading wind farm design and optimization packages, including Openwind, and can be purchased through the Windnavigator or RRAP platforms.

Sitewind® is UL Solutions's wind flow modeling system designed for micrositing. To achieve the best possible results in the design and optimization of the wind farm, the WRG obtained with Sitewind® must be combined with on site measurements, using for example the adjustment tools included in Openwind.

Sitewind® is a combination of two atmospheric models: a mesoscale numerical weather prediction (NWP) model and a microscale wind flow model (Brower 1999, Beaucage et al. 2014). NWP models are the best tools available to simulate the evolving atmospheric conditions, especially the synoptic scale (scales of motion ~100-1000 km) and mesoscale (scales of motion ~1-100 km). The mesoscale model simulates weather conditions for a typical year with a horizontal grid spacing of 1 km. The microscale model then refines the wind fields from the mesoscale model to capture the local influences of topography and surface roughness at a resolution of 50 m. Since 2016, the mesoscale component of Sitewind® has been the Weather Research and Forecasting (WRF) model, a state-of-the-art numerical weather prediction model developed by NCAR, NCEP and others. The microscale component of Sitewind® is WindMap, an in-house mass-conserving wind flow model.

The WRG200 give users the ability to do a complete design and energy assessment at the very initial stage of development of the wind farm, when there are not yet on site measurements. As the WRGs are scaled to Windnavigator's 200 m wind speed maps, which are adjusted with public observations or measurements provided by our customers, their average bias is minimal.

The WRG 200m files are a cheaper and faster alternative to the standard 50 m resolution Sitewind®, but are not intended for detailed plant design or definitive energy production estimates. Rather than performing a full dynamical downscaling as with the Sitewind® modeling system, the 200-m WRGs are generated by UL's in-house microscale model WindMap (Brower 1999) initialized with a virtual met mast. The virtual met mast consist of a time series generated with a mesoscale model With the help of high-resolution terrain elevation and land cover maps, the microscale model adjusts the mesoscale wind flow to capture the local influences of topography and surface roughness. The (raw) WRG is then scaled to the 200 m resolution mean wind speed map found on Windnavigator.