[yuhong]

One of the things they did with the Model 3 was to improve the efficiency of 120V charging, partly for that reason. Trivia: In Canada, the CEC since 2012 requires a NEMA 5-20 outlet for EV charging at a minimum, and with the Model 3 6-7 miles per hour with it is not uncommon.

[walrus01]

It's still not going to be able to pull anything more than about 1700W from a 120V 15A circuit. Maybe slightly more efficient but the bottleneck is the amperage capacity of the circuit. Think of 120V charging as exactly like a hair dryer.

[dougmany]

We use 120 to charge our leaf. It charges at 4 miles per hour. Plug it in after a typical 40 mile day and it is ready in the morning.

[yuhong]

AFAIK for EV charging it is ~1400W for a 15A outlet and ~1900W for a 20A outlet (because the load is continuous), and the difference between the two for the Model 3 is probably around two miles per hour or so.

[sfteus]

Correct, assuming a dedicated circuit in the US, code dictates that it'd be 1440W and 1920W for a 15A and 20A outlet, respectively. Continuous loads can only pull 80% of the max circuit load.

In theory, you could also run a 100% rated breaker to pull more power, but the car would have to be able to support it as well.