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Old 05-11-2022, 09:41 PM   #5 (permalink)
Isaac Zachary
High Altitude Hybrid
 
Join Date: Dec 2020
Location: Gunnison, CO
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Avalon - '13 Toyota Avalon HV
90 day: 40.45 mpg (US)

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Quote:
Originally Posted by oil pan 4 View Post
240v is more efficient too.
12 amps of 240v is nearly 3x as fast as 12 amps of 120v, because it's more efficient.
I don't see that being possible. According to some sources charging at 240V is only about 5 and a half percent more efficient. Of course, it will vary with each setup, from the wiring in your home and EVSE to the charger on the car. But getting "nearly 3x" the charging for only double the power does not make sense in the lightest.

Plus you have to factor in the charge tapering off as it gets closer to "full." I bet that at a 12 amp limit, charging at 240V actually takes longer than half of what it would at 120V even with the small increase in efficiency.

As far as the original question goes the OP was assuming that charging at twice the voltage and twice the amperage was only twice the power, where in reality it's four times the power, hence why it takes close to a third the amount of time. It's about a third and not a quarter of the time because of the charging slowing down as the battery becomes full.

Efficiency does factor in, but it is small in comparison to the four times the power of the level 2 charger.
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