First off, I'm all for renewable energy and I'm pretty optimistic about our ability to get it to work if we really try.
That said... Baseload is a real thing. Especially in industry you have e.g. huge smelters running 24/7 and those eat up loads of power. Certain aspects of traffic need power around the clock and you cannot just shut them down.
I'm in no way saying you can't balance power around but for this you need a grid and that on a global scale just is right now hardly feasible. Europe has trouble with it and even Germany to a degree, and the US is a good chunk larger.

Sidenote :Germany annually publishes a pretty extensive report by their energy ministry which is a drag to read but has enough nice graphs to be able to glance over.