For every 100 MW of wind generation, 85 MW of backup fossil power is required. In Texas, the figure is > 90 percent backup.
Someone I know who delivers parts to some of the wind farms in TX told me he sees a lot of broken turbines when he goes out to deliver. I am guessing they are more prone to breakage with less return, than say the electric plants at Calavera Lake or Braunig Lake near San Antonio. Anybody know?