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Originally Posted by NeilBlanchard
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How does counting all the BTU's in each form of energy carried onboard the vehicle, give an advantage to any one of them?...
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please try to understand what I am trying to relate here, if you don't understand what I am saying in this paragraph, please ask specific questions about it. It IS the answer to your question. My diesel far exceeds the efficiency of an electric car when the source of the energy systems as a whole is considered, which mpge doesn't do. If we had any sort of algae biodiesel distribution network, electricity would be rank in comparison.
Quote:
Originally Posted by dcb
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3. and not least by any measure, Electricity has undergone it's major heat losses at the plant. It has well to walls efficiency of ~%30, where gasoline (possibly better for other liquid fuels like biodiesel) is considered ~%83 efficient. But electricity has not undergone the major carnot cycle transformations, so the deck is stacked for electricity in MPGe. If I take my "%41" efficient tdi, times %83, I get %34 efficiency out of my engine, whereas a %90 efficient electric motor (if it was plugged directly into the wall) would only be %27 efficient. This appears to be a fundamental flaw in the GREET model, there is not a good way to compare electricity (which has already undergone it's major heat loss conversion) to liquid (or gaseous or solid) fuels without looking at the full lifecyle.
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