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by davidgould 2415 days ago
What you keep seeming to miss is that you only charge the amount you drive. If you drive 50 miles you can charge on a level 1 (120V 12A = 1.4kW) in 8 hours while you sleep. It does not matter whether the car is a Spark EV (18kWh battery) or a Tesla P100 (100kWh battery) because you only charge to replace the amount you used up, not the total amount the car could hold.
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If you have a Tesla Model 3, and drive 100-miles in a day (ex: go to work, visit your cousins for their birthday, then come home), it will take 14-hours on a regular 120V x 15A charger to recharge those 100-miles.

8-hours of charging on 120V x 15A charger only charges 55 miles. You won't "recover" the 100-miles until 20-days later (-100-miles from a big-driving day, +55 miles of charge on Day1. -50 miles on the 2nd day, +55 miles on Day2, etc. etc).

Realistically speaking, the 120V x 15A charger is simply insufficient for people who actually drive 50-miles a day (and occasionally drives 100-miles).

Factor in the 33% loss of energy in the winter, factor in a mistake or two (ex: forgetting to plug in the vehicle), factor in a few nights without power (ex: hurricane or California Fires), and you're completely sunk.

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If you're buying electric, you need the 7kW charger (or faster), to ensure that your vehicle is fully topped off every night. That way, on your "emergency" days when two or three things happen (hurricane + visiting the cousins), you'll have enough charge to actually make it through the day.

Alternatively, buy a PHEV so that you can always leverage gasoline in those high-milage or power-outage situations.