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Old 05-14-2021, 01:06 PM   #30 (permalink)
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Originally Posted by EcoCivic View Post
Thanks for letting me know, I never heard of that. I just know that alternators are generally only about 50% efficient. Do you have a link to any information on that?

Unplugging one of the fans wouldn't work, I live in the south and we see 100+ degree days here. The engine cools fine with 1 fan, but the AC doesn't work well at idle and low speeds with only half of the condenser getting cooled off and the compressor drags the idle down noticeably more than with 2 fans. The extra power the compressor draws from the higher head pressure would almost certainly outweigh any efficiency benefit from the power savings as the compressor uses much more power than the fans.
'Improving Alternator Efficiency Measurably Reduces Fuel Costs', by Mike Bradfield, MSME, Remy Inc. ( DELCO REMY ), 2008
* starting with fuel to the engine at 100%
* the engine is 40% efficient
* the serpentine belt/pulley is 98% efficient
* the alternator is 55% efficient
* the electric radiator fan motor is 92% efficient
* The airfoil shaped cooling fan is 90% efficient
From the gas tank to the air actually moved by the electric fan, total efficiency is 17.3 % ( 82.7% of all the energy is lost )
If the fan is running at all, at 40-mph or above, something's wrong.
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