$0.21 was from memory, so I pulled up my bill and it was actually low:

Southern California Edison on the time-of-use plan, charging during "Super off peak." Note that nowhere on the bill do they show one number for how much you pay per kWh. These numbers will change next month as we go from "Winter" to "Summer"

Delivery charges: $0.17664

CCA Cost responsibility surcharge: $0.02007

Nonbypassable charges: $0.00644 + $0.00591

Fixed recovery charge: $0.00619

Generation charge: $0.05958

Unless I typoed something again (oops 800k) that works out to $0.27 for the cheapest I can pay in winter. I compared last fall and this was by far the cheapest plan offered to me for overnight charging.

Varies widely by state and other factors. I'm at around $0.18 for 1kWh when you look at the overall bill including generation, supply, and all other fees.

(My car averages 3.3 miles / kWh, so ~$0.055 / mile assuming 100% charge efficiency... I'm using a 120V outlet so it's probably 75-80% charge efficiency, pushing the cost to ~$0.068 / mile.)

I was at $0.12 3 years ago, but rates have jumped (and there's two more years of planned rate increases coming up)

And yet half what they charge in some areas of California