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Old 02-10-2009, 03:20 AM   #15 (permalink)
ConnClark
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Join Date: Jun 2008
Location: Richland,WA
Posts: 985

Das Schlepper Frog - '85 Mercedes Benz 300SD
90 day: 23.23 mpg (US)

Gentoo320 - '04 Mercedes C320 4Matic
90 day: 22.44 mpg (US)
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Quote:
Originally Posted by MetroMPG View Post
It's not necessarily a problem - power plants (even coal fired ones) generate power more efficiently than gasoline engines, so the net energy use is lower. Also, many people have access to renewable (clean) electricity generation so net pollution is lower too.
Lead acid batteries are about 75 to 85% efficient. ( http://www.sandia.gov/pv/docs/PDF/batpapsteve.pdf )

A 14.4V charger is about 86% efficient. (
stepdown transformer 95% efficient * efficiency due to diode losses = .95 * (1 - (1.4/14.4)) = 86% )

average efficiency of powerplants = 33% Power Plant Efficiency Hasn’t Improved Since 1957 : CleanTechnica


transmission and distribution efficiency = 93.9% http://tinyurl.com/dghtoh


so 100% * .33 * .939 * .86 * .85 = About 23% efficient. Just about the same efficiency as a typical car engine
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