how long do wind turbines last?

Answer 1

As long as they are properly maintained they seem to last forever.

Simple example are the old windmills (a windmill is a simple form of wind turbine...) one finds in Europe. Some date back hundreds of years.

The modern electric generating wind turbine farms near where I live have all held up well for the last twenty or thirty years. I remember when they were built... the ones that have received maintenance are fine - the sets that don't receive it (investors bailed out I guess) have begun to rust and even fall in some cases.

-dh