Topic: Electric water pump

[Jeep_Lust]

  But in the case of an alternator, there would be no increase.

Well, I figured out last night why no manufacturer has ever made an exhaust driven alternator: alternators don't use enough hp, even at max output, to make it worth the trouble.

1 hp is ~ 750 watts (746, to be exact)

Watts = amps times volts

Alternators charge at 14 volts.

Let's say that we've got a 100 amp alt.

100 amps x 14 volts = 1400 watts.

Alternators aren't 100 % efficient, so let's say that it takes 1500 watts input to get a 1400 watt output.

1500 watts / 750 (watts per hp) = 2

So your 100 amp alt at max output only uses 2 hp. Not worth all of the hassle associated with a turbo.

Oh well. I said that I was a kid when I drew it up...

[flyingbrick]

(1Hp = 746Watts ) is'nt that only good for motors? Not for calculating the load of an alternator/ generator.

[Jeep_Lust]

Power is power. Hp converts to Watts which convert to BTU's which convert to Joules, etc.. If there's a speciaal formula for determining power req'd to drive a generator, I'm not aware of it. (Which doesn't mean that it doesn't exist!)

Power out has to equal power in times the efficiency factor (losses to heat & friction).

I may be being too generous by saying that 1500 watts in will put out 1400 watts, but it made the division easy...