I read a detailed study on this 20 year life problem. Given the difficulty of recycling the beasts, a 20 year life is too short to make it economical. Gas fired plants on small plots of land cost less and last a lot longer.
And a 20 year tax abatement from the local pols.
When that’s gone, so will be the current windfarm owners
Heck, a twenty year life for windmills is very optimistic!
There are no subsidies for maintenance and scrapping: I will be surprised if 12-15 years is ever exceeded. 10-12 most likely.