I have long been very interested in the question of how much it (does not) matter(s) when one plugs one's electric vehicle in, especially if, like I do, I have the choice of plugging into a home rooftop solar system.
Many years ago, I wrote extensively on this web site/blog about the many intricacies and complexities of what I call "solar offset" charging of an electric vehicle vs. directly filling up with electricity that has been/is being produced directly by a (home rooftop) solar system connected to the same electrical box into which an EV charger and/or the wall-socket into which you're plugging your EV into.
We recently had two solar systems installed here at Highline Crossing Cohousing in Littleton, Colo.
Sometimes a picture is worth a thousand words.I shot this picture from the 8th floor of Children's Hospital in Aurora, Colo. just now. My blue solar-charged, all-electric Chevy Bolt (roughly in the center of the photo) is dwarfed by the SUVs and pick-up trucks that are parked right next to it.
In the more than 10 years I have been doing SolarChargedDriving.Com and advocating for solar-charged driving, the electric grid has gotten considerably cleaner in the United States -- and in many places around the world.