How much power does the A/C take?

[petrivanzyl]

So I've read a couple of different views on this.

Some people say it is as much as 15kw. I read somewhere that on the E90 is was closer to 3-5kw. But I'm wondering whether it is down to 0 on the F30.

The F30 keeps on the A/C even when the engine switched off with stop/start. So then it clearly runs on the battery, which was charged from the brake energy recovery. So it would stand to reason that the A/C also draws no power from the engine while driving if the battery can charge it?

What do you guys think?

 

[abmi0000]

Most likely electric and not belt driven

 

[Sabretooth tiger]

On my Nissans it felt like it was half the power.:bangdesk:

 

[SP33DYV]

On my Nissans it felt like it was half the power.:bangdesk:

+1, but the Nissan had a very potent Aircon!

 

[Twinz]

The drivetrain loss is significant with aircon on.

 

[petrivanzyl]

The drivetrain loss is significant with aircon on.

Significant?

 

[SP33DYV]

According to the web it's around 3-5 HP.


Sent on the run from my iPhone using Tapatalk

 

[Zack]

I've heard guys say it can be up to 10hp. So on a 100hp car it'll make a huge difference. But in your case with the 320d you more than likely can't feel it with all the torque. :rollsmile:

 

[petrivanzyl]

But would it still use up the horses if its electrical?

 

[Perry]

Hi all
Also, a car can take you to places that do have A/C, and I’m not too proud to admit that when our power was out, we drove to a mall almost solely for the purpose of enjoying the cool air.

 

[moranor@axis]

But would it still use up the horses if its electrical?

this would depend on if the alternator has to work to charge the battery...

 

[moranor@axis]

a supercharger eats a maximum of 20% engine power it moves and compresses way more air than you AC could ever dream of...

lets take the old C 230 Kompressor with an eaton M62 SC it has 142 kW at high boost the SC consumes max 15kw...

the guys claiming the AC uses 15kw are on crack i would be surprised if it even uses 3-5hp

 

[petrivanzyl]

Still 3 horses to pull the A/C is not bad...

 

[Philip Foglar]

On a petrol motor you will feel the effects of an aircon compressor more than you would with a torquey diesel, especially at lower revs. But cannot really say that I can feel a massive difference in my car, just the throttle response is slightly different as usual.

a supercharger eats a maximum of 20% engine power it moves and compresses way more air than you AC could ever dream of...

lets take the old C 230 Kompressor with an eaton M62 SC it has 142 kW at high boost the SC consumes max 15kw...

the guys claiming the AC uses 15kw are on crack i would be surprised if it even uses 3-5hp

The Mercedes SLR's supercharger apparently needs the power of a GTI engine just to power it!!! No wonder that thing sounds so insane! raise:

 

[P1000]

It can be up to 10kW for a big car. The newer cars can vary the pressure ratio, and so also the amount of power the aircon takes (especially usefull when you put your foot flat - the aircon is basically freewheeling then). There is basically no way you would have an electric aircon that works well - you just need to much power. Most likely, the compressor is belt driven off the engine, and thus also not operating when the engine is off, but the evaporator would still be cool enough(/designed with enough thermal mass) to cool the air until it is time to start the engine again.

 

[XMAX]

It can be up to 10kW for a big car. The newer cars can vary the pressure ratio, and so also the amount of power the aircon takes (especially usefull when you put your foot flat - the aircon is basically freewheeling then). There is basically no way you would have an electric aircon that works well - you just need to much power. Most likely, the compressor is belt driven off the engine, and thus also not operating when the engine is off, but the evaporator would still be cool enough(/designed with enough thermal mass) to cool the air until it is time to start the engine again.

Makes Sense