U.S. Average Annual Wind Speed at 80 Meters
The U.S. map shows the predicted mean annual wind speeds at an 80-m height, presented at a spatial resolution of 2.5 kilometers that is interpolated to a finer scale. Areas with annual average wind speeds around 6.5 meters per second and greater at an 80-m height are generally considered to have a wind resource suitable for wind development. Utility-scale, land-based wind turbines are typically installed between 80 and 100 m high although tower heights for new installations are increasing—up to 140 m—to gain access to better wind resources higher aloft.
In early 2010, the National Renewable Energy Laboratory (NREL) completed a preliminary review and validation of AWS Truepower's 80-m height map estimates for 19 selected states (six Western states, six Midwestern states, and seven Eastern states) based on tower measurements at heights of about 50 m and above from more than 300 locations. The results of the validation showed that for most regions of the United States the wind resource estimates were well within 10%, which confirms that these wind resource maps are a valuable tool for wind energy prospecting.
Before you plan to install your own wind turbine, you must know if the wind resource in your location is adequate. From wind resource maps, you can determine if your area of interest should be further explored. The average wind speeds indicated on this map are model-derived estimates that may not represent the true wind resource at any given location. Small terrain features, vegetation, buildings, and atmospheric effects may cause the wind speed to depart from the map estimates. Expert advice or detailed wind resource assessments should be sought when estimating energy production potential.