While most hybrids are said to use one to two litres of fuel per 100km, a study claims they need six litres on average
Plug-in hybrid electric cars (PHEVs) use much more fuel on the road than officially stated by their manufacturers, a large-scale analysis of about a million vehicles of this type has shown.
The Fraunhofer Institute carried out what is thought to be the most comprehensive study of its kind to date, using the data transmitted wirelessly by PHEVs from a variety of manufacturers while they were on the road.
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According to the study, the vehicles require on average six litres per 100km, or about 300%, more fuel to run than previously cited.
The scientists of the Fraunhofer Institute found that the main reason for the higher-than-stated fuel usage was due precisely to the fact that the PHEVs use two different modes, the electric engine and the combustion engine, switching between both. Until now it has been claimed by manufacturers that the vehicles used only a little or almost no fuel when in the electric mode. The studies showed that this was not in fact the case.
No, this is poorly framed information. They don’t “require” on average 300% more fuel to run. The drivers choose to charge their cars 300% less often than manufactures suggest. This is skewed by rental and fleet cars whose users never charge the car, and by owners who treat their car as a normal hybrid instead of charging it. I was once given a plug-in hybrid van as a rental car but never told it was a PHEV. I didn’t figure it out until the next morning when I was walking up to it and saw the charging cover. My hotel didn’t have a charger, so I couldn’t really do anything about it; but if I were a normal person and not someone who has owned multiple EVs then I wouldn’t have even thought to charge it.
Also, the Porsche one makes total sense. The car is going to burn through battery charge and then hit the gas engine faster when, as expected, Porsche drivers drive them like a Porsche.
It really is insane. They only rate the range for 29 miles and then get 22-29MPG and make something like 540HP. I wonder (but didn’t bother looking up) if their design allows the electric motor to boost the power of the gas engine rather than boost fuel economy in which case you’re talking about smiles per gallon not miles per gallon.