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For you techie folks that want to calculate power usage and remaining SOC, here is some information you may find helpful.

The electric heater booster/PTC initially requires up to 4 kW peak power, or approx. 3 kW at -15°C or 2 kW at 0°C. As soon as the interior compartment has reached the desired temperature and the temperature only needs to be maintained, the power is approx. 1.5-2 kW.

Additional consumers (12V electrical system) in the electric vehicle are supplied by the HV battery and not via the alternator as in vehicles with combustion engine

(Guideline values: Lights: approx. 130W / Heated rear window: approx. 150W / Seat heater: approx. 100-150W per seat / Blower: up to 500W)​
 

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(Guideline values: Lights: approx. 130W / Heated rear window: approx. 150W / Seat heater: approx. 100-150W per seat / Blower: up to 500W)

Were these measured numbers? For the lights I'd calculated about 150W plus a bit more if you're using your turn signals, backup lights and/or 110W more if you're running high beams.

It would certainly be nice to reduce the blower usage somehow.
 

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Yes, but you don't rate the fuse equal to the nominal current draw. A 25A fuse means the designer did not expect current over 20A.
Which is why I stated:
Likely it's under 250W though.
20A*12V = 240W, which is about the max one would want to load a line fused at 25A. As for the other items on that fuse/line, they're rather small in comparison, and probably not regularly running services.

My point wasn't that I demand the heater take 240W. It was that the 500W estimate was at least double what it likely would use at max. The 25A fuse would limit it to 300W as a theoretical max, with it likely being under 250W based on real world wiring.
 
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