power of all electrical system on the car

[lhh2k]

Does any one know that each car need how much power for all electriccal system on its and air conditioner, heater.

 

[MacGyverS2000]

Too generic of a question to answer... it depends on the specific car and what accessories are being used. I wouldn't imagine the heater takes much energy as it's typically pulled from the engine heat (radiator core). Both A/C and heat use the fans, so...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[Fabrico]

That's simple, it's stamped right on the alternator.

 

[lhh2k]

that i want to know is how much power it divert from the engine to the all auxilliary for van,sedan,suv.

 

[TheBlacksmith]

Not much. Since the largest alternators these days are about 100 amps, at about 15 vdc, that is maybe 1500 watts, or about 2 horsepower. (1 hp = 746 watts)

 

[lhh2k]

you just said about alternator, how much power to run a/c. I think that it need more power than alternator.

 

[Fabrico]

There are many car and SUV alternators that top 200 amps these days.

 

[TheBlacksmith]

Okay, make that about 4 hp. With the typical SUV making around 300 hp, its still a drop in the bucket. We did some testing years ago at the boat engine company on multi-rib belts and determined that the freshwater (engine jacket) pump, the raw water (water from outside the boat for engine cooling), power sterring pump and 65 amp alternator together only required about 5-7 hp.

 

[reidh]

TheBlackSmith: The typical SUV may make 300 HP (which is probably a little high as most SUVs are V-6's) at 6000 RPM, but at low speed it would be in the ball park of 1/4 of that value, or 75 HP. I would not consider a 6% (4/75) power reduction a drop in the bucket.

Ihh2k: The power requirements for a vehicle will vary significantly. Does the car have air conditioning, electric water pump, electric power steering pump, heated seats, electric mirrors, power sliding doors/liftgates, what type of electronic ignition does this vehicle have, etc.

Chances are you would never use all of these items at the same time. For a general answer, I would agree with Fabrico and use the alternator power rating as a guideline.

 

[patprimmer]

I would expect the maximum continuous electrical use to be driving on a hot rainy night on the highway, with A/C and demister going full blast, all lights on, ignition/engine management system, fuel pump, and wipers on full speed.

The alternator should be rated to cover this, plus I would guess about a 20% safety factor to cover intermittent use of things like brake lights, electric power steering, electric windows, central locking etc, and to be able to replace charge lost while the engine was not running.

Regards

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[lhh2k]

I would like to know max power that the engine divert for all things in the car, except tranmission. It means that how many percent of power they take from engine to work. I have read some material, it said that they take 20% power from engine. However, i'm not sure.