IIRC, it would take 180,000 windmills to generate 20% of the energy America currently uses. It would take an area the size of West Virginia to accommodate that many windmills. Worth it? I think not.
AND ON TOP OF THAT...
When the wind is only blowing at 10% or 20% of the velocity needed to make rated capacity - OR on those many calm, still winter days when there is NO wind BUT lots of demand for electricity for heat...
YOU STILL NEED THE SAME NUMBER OF GAS OR COAL FUELED POWERPLANTS THAT YOU EVER NEEDED, all the time.
And they are NOT amenable to starting and stopping depending on the wind. They have to run at least at a low idle rate all the time.
THUS wind power as a viable part of the grid, is a canard.
;^)