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You need a garage, and a circuit with 60A capacity. Most houses built today have 200A total capacity, older homes are 100A. At some point the electric grid will need updated.



You need 60amps for high speed charging, but can't you plug into a 15 amp outlet and charge overnight?

You are correct that the grid will need updating - all those houses using 15 amps more add up.


Yes, but it is quite slow. Even 12 hours of charging might not be enough for someone's commute. For example, let's look at Honda's PHEV, the Clarity.

17kWh battery.

47 miles EV range.

Charge time @ 120V = 12 hours. It essentially can charge up to 4 miles of range per hour on a standard circuit in a US home. Cold weather? Your power needs go up, range goes down, and charge rate drops as well. 15 amps @ 120V EV charging is not practical for most EV owners, at this time, but you are correct that it is possible.


Why would you pick a PHEV for comparison? They are going to get a worse MPGe (because of the extra weight) and have a smaller battery (no catching up on charging during the weekend).

But more importantly, they can backup to gas so if you can only do 80% of your trip electric there is no real problem, you still are getting great fuel economy.


Slow and steady "wins the race" though. An average car is parked more than 12 hours a day. (The average is even closer to 23 hours than it is to 12 hours.) You easily cover the average commute even at 4 miles range added per hour (and as sibling post points out, some EVs do even better than that in a Level 1 charge) even just charging a car ~50% of the time that car spends parked.


Average commute for the US is 26 miles a day, but more than half drive considerably less than the average.

For the people for whom an electric car makes sense, the overwhelming majority could make due with a level 1 charger (12 amps 110 volts).

L1 charger provides 4-5 miles of charge per hour, so 8 hours in the garage at night would more than make up for the commute. If you have a larger range (200+ miles) you can make it up on the weekends.

If you have a 100+ mile commute each day, sure get a L2 charger. Or better yet, buy a hybrid.


The average car gets what, 12K miles a year? That's about 8 hours a night on average. You could easily get by without a 60A socket, and even if you do have a fast charging socket you're not going to be pulling 50A all night.


L2 chargers draw 30A, you only need a 40A circuit for that.




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