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Originally Posted by sendler
Do you have a link which outlines the measurement procedure? I'm still having a hard time accepting the results where the Spark is beating the Leaf.
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While the Spark and Leaf have similar drag coefficients of about 0.32, the Spark has less frontal area. Not only that, but it weighs a whopping 1,000 pounds less than the Leaf.
I'm not surprised the Spark is more efficient with its electrons than the Leaf.
The Leaf is a fairly un-aerodynamic porker of a vehicle. In my opinion, the design fails both form and function because it is a very unattractive vehicle.
I do think Tesla will eventually pull ahead of the competition by selling affordable, well-engineered, attractive vehicles.
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For battery electric vehicles, the U.S. Environmental Protection Agencys formula to calculate the battery-to wheel MPGe is based on energy standards established by the U.S. Department of Energy in 2000:[1][7][8]
MPGe = \frac { E_G} {E_M*E_E} = \frac{ 33,705 } {E_M}
where
MPGe is expressed as miles per gallon gasoline equivalent (as shown in the Monroney label)
E_G = energy content per gallon of gasoline = 115,000 BTUs/gallon, as set by U.S. DoE and reported by the Alternative Fuel Data Center.[8]
E_M = wall-to-wheel electrical energy consumed per mile (Wh/mi) as measured through EPA's five standard drive cycle tests for electric cars and SAE test procedures[7][30]
E_E = energy per KWatt-hour of electricity (BTU/Wh) = 3.412[8]
The formula employed by the EPA for calculating their rated MPGe does not account for any fuel or energy consumed upstream such as the generation and transmission of electrical power, or well-to-wheel life cycle, as EPA's comparison with internal combustion vehicles is made on a tank-to-wheel versus battery-to wheel basis.
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Miles per gallon gasoline equivalent - Wikipedia, the free encyclopedia