After How Many KM Will Car Battery Recharge in Winter with Heated Rear Window & Air Supply?

I would like to know how long the battery is recharged in winter, i.e. how many kilometers do I have to drive to get it charged sufficiently, considering that at the beginning of driving I use the rear window heating and use the air supply in the car and the radio throughout the ride?

If it is not a traffic jam but smooth driving at relatively high revs, then with the current reception as you write, after a dozen or so km, it will only be charged, you would have to drive a few, maybe even several hours for the battery to be fully charged.

It will be safest if you check it yourself. It all depends on how quickly you start the engine. Assuming it is -20 ° C and the engine will be able to start, for example, in the third time, as you know, you will discharge it to a greater extent than, for example, in spring, where the temperature outside the window is positive. To be sure, after turning off the engine, measure the voltage on its clamps. For a 12V battery, the voltage should be between 13-14V. If the voltage is too low, the battery is undercharged. Too high a voltage damages the battery internally, which significantly shortens its lifetime. It is best to take the measurement after about an hour from turning off the engine, it will allow you to avoid erroneous measurements related to a temporary excess voltage in the battery ...
best regards

I have been doing some dodgy experiments towards measuring the battery charging current. It will be difficult to clearly define the value in km. First of all, you did not write what battery and what car it is.

Personally, I think (I can be wrong, of course) that the car installation (read alternator) treats our battery neglectfully, because the regulator maintains a constant voltage in the electrical system. Imagine a situation when you spin for a long time to smoke. The battery will be deeply discharged, i.e. its voltage will drop (e.g. to 12V). When the engine starts, the voltage in the installation will be, for example, 13.8V. This means that the charging current can amount to several dozen amps (measured in VW Golf). Of course, such a current will flow to the battery for a short time, then it will decrease (after two hours of driving, the charging current for me was less than an ampere - so you can take the eye five times that the battery was charged - my mistake was not measuring the density of the electrolyte).
You need to approach the topic like this: first, we unload (start) the battery. The "size" of the discharge is the starter current times the turning time. Then the battery is charged from the alternator - this is also electricity times time.
As both currents are hard to tell, it will be hard to tell the time (which is your kilometers) to charge.
A lot will depend on whether your car is smoking on a tick or you have to spin a minute.
Certainly, a 5-minute drive (5 km) is not enough to fully charge it. The best solution will be your own experience. Light up in the morning, drive 50 km, and after an hour measure the electrolyte density. The battery is fully charged when the electrolyte density is 1.270 - 1.280 kg / L. Sorry for the long talk, but I wanted to explain it somehow.

It is a philosophical rather than a technical question, in this case the state of charge of the battery is influenced by many factors (battery capacity, age, condition of the generator or alternator). In winter, it is best to support the battery by charging it with a rectifier, but with low currents. The fuel prices are such that it is definitely not profitable for an alternator or a generator to do it.