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Old 02-11-2014, 10:30 PM
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Quote:
Originally Posted by racingbmwm3 View Post
would need to know the efficiency of the alternator, but let's say you have front and rear heated seats, each pulling 15amps at the high setting? ~200W/seat (@14V). ~800W total. If the alternator was 100% efficient, that is about 1.1HP. even assuming a horrible efficiency of the alternator of maybe 50%, that's 2HP.
Interesting calculation. I'd use 80% for the alternator, less 10% on the belt drive.

But if it means 1.5 hp, that is about 5% of the 30 or so hp required to maintain steady state cruising speeds. That's measurable.
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