Do You Have Enough Wind to Run A Windmill?


The "Wind Resource Atlas of the United States" will give you a rough idea if your area has wind potential.


Here is how to use it.



Find the Wind Map for Your State:

This section provides maps of each state -- look down the list of links to find the wind map for your state:


Here is a sample for Montana:


From the map for your state, find out what Wind Class your area is in.  The Wind Classes are numbered from 1 to 7 -- the table below from the Wind Atlas gives the definition for each wind class.  The paragraph below tells you what the wind potential is for each Wind Class.


"The wind resource maps estimate the resource in terms of wind power classes (Table 1-1), ranging from class 1 (the lowest) to class 7 (the highest). Each class represents a range of mean wind power density (in units of W/m2) or equivalent mean wind speed at the specified height(s) above ground. Areas designated class 3 or greater are suitable for most wind turbine applications, whereas class 2 areas are marginal. Class 1 areas are generally not suitable, although a few locations (e.g., exposed hilltops not shown on the maps) with adequate wind resource for wind turbine applications may exist in some class I areas."

Even if you are in a class 3 or above area, you will still need to do an assessment of your site to see if it will work, but at least you know there is some potential.


Table 1-1 Classes of wind power density at 10 m and 50 m(a)



(a) Vertical extrapolation of wind speed based on the 1/7 power law.

(b) Mean wind speed is based on Rayleigh speed distribution of equivalent mean wind power density. Wind speed is for standard sea-level conditions. To maintain the same power density, speed increases 3%/1000 m (5%/5000 ft) elevation.