You can't always 'build them somewhere else' -- wind farm locations aren't arbitrary. Solar is a little less constrained in this way, but still has some location requirements (you wouldn't put a solar plant on a hillside that is shaded half the day.)
There's also losses from transmission of the generated energy. The further you generate from where you use, the more loss you have to account for.
There's also losses from transmission of the generated energy. The further you generate from where you use, the more loss you have to account for.