September 18, 2025
The AC system in an EV draws power directly from the traction battery.
When the car is plugged in, electricity from the charger is used both to charge the battery and to power any active systems like climate control.
If the AC is running, some of the incoming energy is diverted to operate the compressor and cabin fans instead of going entirely into the battery.
Slower charging: The battery charges more slowly because a portion of the electricity is being consumed by the AC system.
Minimal impact at low power AC usage: If the AC is running lightly (e.g., fan only or mild cooling), the effect is small.
More significant impact at high AC demand: Running full-blast cooling or heating can noticeably reduce the charging speed.
No risk of damage: Modern EVs are designed to handle simultaneous charging and accessory usage.
Thermal management: Running AC while charging may even help keep the battery and power electronics cool, which can be beneficial in hot conditions.
Summary:
Running the AC while charging is safe, but it can slightly reduce the charging rate because some of the electricity is used to power the climate control system instead of charging the battery.
