I've read a few articles saying that there is so much Solar adoption in the U.S. that there is a surplus at some times (summer days I believe). It use to be that there was too much use from home AC systems so power was expensive during the day. It seems to be switching to night now as so much is generated during the day (with just 3% adoption of rooftop Solar).

Here's an example of one article on the matter, which I just skimmed a little.

http://www.latimes.com/projects/la-fi-electricity-solar/

I'm guessing that CPU's use a whole lot less electricity than things like AC systems, so they probably don't affect total electricity used by that much. I was able to surmise that a 3 ton central air conditioner uses around 3500 watts per hour while an Intel I7 (whole system) uses around 150 watts per hour.

My theory, then, is that this won't affect total power use in the U.S. all that much.