The operative phrase is "spinning reserve." In order for your grid to remain stable, you need a "mirror" of sorts. You need 80-90% of your "renewable" capacity in conventional power plants, and that 80-90% must be in a condition known as "spinning reserve," from which it can kick in and go online instantaneously when the renewable source craps out.
The newer coal-fired generating stations are very nearly zero emissions but in the process of making them so clean they also were made unsuitable/unable to operate in spinning reserve. And nuclear plants only have two speeds: off and WFO. So there's no point having one in spinning reserve because it costs the same whether it's online or not.
The insanity is that they've always known it wasn't possible to build a stable grid purely off "renewables," that that plan was always going to necessitate a "ghost" power system capable of producing >3/4ths of the "primary"/renewable system's maximal output, and that that spinning reserve/ghost/back-up system would cost exactly as much to build and only slightly less to operate than as if it were online full-time.
And you're wasting all this money on a mirror of back-up power plants entirely so you can beat your chest and brag that your primary power sources run on "renewables."
Except for the ghost/back-up system, which is all that makes the "renewable" generating stations a functioning component in a stable power grid.
For renewing your green energy approximations.
“... from which it can kick in and go online instantaneously when the renewable source craps out.”
Another solution is to instantaneously turn off the power to millions of household as is done in California.
See, you just got to think out of the box.