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Question: Is Model 3 Charging Rate at a SC affected by AC use ?

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SageBrush

REJECT Fascism
May 7, 2015
14,851
21,477
New Mexico
I should have checked when I was at Superchargers this week ...

I see up to 114 kW on the car app while charging. I'm curious whether unused Supercharger power can be used for AC. My guess is no but I'm not familiar enough with the power flow to be certain.
 
I should have checked when I was at Superchargers this week ...

I see up to 114 kW on the car app while charging. I'm curious whether unused Supercharger power can be used for AC. My guess is no but I'm not familiar enough with the power flow to be certain.

~99% certain the answer is 'yes' but given the amount of energy the A/C uses any time added to the charging session is probably measured in seconds...
 
Unless the car is drawing the absolute maximum from the supercharger, the AC won't impact it. The car will draw a little extra to cover the power needed for the AC...

But, keep in mind that even if the car IS drawing the maximum from the supercharger, in most climates this means the AC is running full blast anyway to help cool the battery. You can hear our X from a mile away when it's supercharging unless it is winter time
 
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Reactions: SageBrush
The AC draws something like 3-4 kW of energy when running at max in my model s. It could potentially take a little away from charging however two things to consider:
  1. The difference in charging speed is probably barely noticeable since that’s a pretty small proportion of the charging power in most parts of the charging taper except for people charging to really high SOC levels near 100%
  2. Most importantly - and I don’t know the answer to this - we don’t know whether the power to run the climate control for the cabin comes out of the max charging power enforced by the car’s programmed charging taper or not. The SC is rarely putting out something close to its max output to your car. If the climate power comes out of additional kW not reflected on the charging screen it won’t make any difference in charging speed.