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>>”No it isn’t. The vast, vast majority of electric car charging happens at night when there is a couple hundred gigawatts of unused grid capacity” <<
Not so at all!
The vast majority is done during the work day, between when employees arrive and depart.
Power companies, counties, states, all provide card-lok charging stations for electric cars. Few people are willing to pay the $4000 installation cost for a home charger.
Wow, that is completely false! There was an article a few months ago about how most Chevy Volt owners just use a standard 120 V household outlet to charge overnight. That is because you can fully charge the car in 10 hours using such an outlet, even less if you didn't use the entire 40 mile range the day before. (78% of Americans drive less than 40 miles a day to and from work, and 51% drive less than 20 miles[1], so this is likely.)
Furthermore, your $4,000 price for 240 V home chargers is total baloney. Prices are between $500 and $1,000.
The fact is, almost all charging is done at night, in people's garages, when there is no strain on the grid.