Does charging with a 240 V fast charger plug at home (30 mph) use more electricity (cost more) than charging with regular 110 V (5 mph) charger? Thx

[Fellini]

Does charging with a 240 V fast charger plug at home (30 mph) use more electricity (cost more) than charging with regular 110 V (5 mph) charger? Thx

 

[bedoig]

No, it actually uses less on 240 due to the fixed overhead incurred while the car is awake and charging. A slower charge means you're running with that overhead for longer and wasting more power.

 

[MY1stEV]

240v charges more efficiently.

When I look at 120v (NEMA 5-15) charging sessions in Teslafi, they show efficiency ratings between 75% and 85%. Charging sessions at 240v (NEMA 14-50) are 95% and higher.

 

[ucmndd]

As others have implied, the car has a fixed overhead when awake of about 300 watts to power the charging circuitry, onboard computers, etc.

300 watts is a much bigger share of the ~1400 watts you get over a 120v NEMA 5-15 than the ~7600 watts you can pull from a 240v outlet using an appropriate mobile connector adapter, so 240v charging is much more efficient.

 

[Fellini]

Thank you all for replying. That's exactly what i wanted to hear. A scientific response that would put my mind at ease.