Further they never can no matter what happens in the tech.
And the reason is Base Load Power plants have to be on 24/7 They have to produce electricity at a steady load the entire time.
How can that be done with wind, which does not blow all the time at a rate that is reliable, and solar, which does not have a power source for a large chunk of the 24 hour day due to cloud cover and the fact the Sun doesn't shine at night?
If you like you cheap, reliable electricity, you can keep your keep your cheap, reliable electricity.