[Dylan16807]

It's not that much power compared to the terawatt or so of peak capacity, and the "instant" nature of a single car doesn't affect the overall grid in the slightest.

For some rough math, people drive 10 billion miles per day in the US, and at 3-4 miles per kWh that's an average of 105-140 gigawatts. Average production is half a terawatt, so replacing half the cars on the road might only need 10% more average power production, and almost all of that charging can be done off-peak without an impact on transmission.

In the optimistic case, electric cars can even reduce peak loads on big distribution lines.