wind maps

When considering whether or not wind energy is applicable in your location, an accurate wind map can be an invaluable resource.  One place to start is with some of the national and regional level wind maps available through the site provided by the National Renewable Energy Lab (NREL)  at www.nrel.gov/gis/wind.html. This site offers both a national wind resource assessment of the United States and high-resolution wind data. The national wind resource assessment was created for the U.S. Department of Energy in 1986 by the Pacific Northwest Laboratory and is documented in the Wind Energy Resource Atlas of the United States, October 1986. This national wind resource data provides an estimate of the annual average wind resource for the United States. The wind resource assessment was based on surface wind data, coastal marine area data, and upper-air data, where applicable.

Here is an example from the NREL site of a national wind map showing the Average Annual Wind Power for the US.

National and regional wind maps can give you the big picture but if you really want to understand what is going on locally you need a state and local wind map. The NREL site has wind maps for most individual states.  In addition, many state energy departments or commissions provide state and local wind maps via the Web.  Below is an example of a state level wind map for California provided by the California Energy Commission.

When reviewing wind maps it is helpful to see if you can find maps which show not just average wind speeds but seasonal wind speeds.  The wind speed can vary dramatically by season in many locations.  This is especially important to know if you are living off-the-grid and would be relying on wind or a combination of wind and solar to provide your power.  If the wind doesn't blow much in winter and you are relying on it for energy it is good to know up front.  The good news is that wind and solar energy tend to be inversely related and often the worst season for solar is the best season for wind.  By looking at seasonal maps for both wind and solar you can determine if this is true in your location.

Another factor to take into consideration when looking at wind maps is the altitude.  Some wind maps provide wind speeds at higher elevations which may not reflect ground speeds.  Remember, a good rule of thumb is that the wind at ground level needs to be between 7-9 miles per hour if you are going to have sufficient power.