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.
Misleading article. Someone reading this may think that a PHEV will have higher fuel consumption than claimed. When it reality it should be clarified that fuel efficiency is based on roughly 75% electric drive share.
I see the point where they should adjust that down based on real.world usage.
But… if you are expected to drive 75% electric based on battery range and your usage, you will hit the manufacturers claims, give or take
How is it misleading?
Manufacturers make claims about fuel consumption. Based on studying real-world data, fuel consumption is significantly worse than claimed. The study authors say that internal combustion engines are active much more frequently than claimed. They propose that manufacturers and regulators use real-world data because it’s more accurate. Is that such a bad idea?
Its misleading because they’re pushing this like it’s Dieselgate when in reality it’s just that the “MPGe” rating (and metric equivalent) is just a dumb fucking estimation. Porsche states that you get 29 miles electric range at most and then everything else is 22-29 MPG. That’s how PHEVs should be quantified.
Imagine a Porsche owner driving 20 miles to work, charging, and then driving 20 miles back home. How much fuel was used?
Now imagine another Porsche owner driving the same 40 miles but in one trip. How much fuel was used?
How about a third Porsche owner driving 20 miles but flooring it after every stop light in cold weather, not charging, and then driving 20 miles back home. How much fuel there?
These would all give wildly different results which is why any combined estimation will be wrong regardless of the method. Same goes for ICE vehicles but to a lesser extent since they’re always burning fuel. Combined city/highway is going to be different if that ratio is 90/10 versus 10/90. Its going to be different based on weather, driving style, number of passengers, etc. The whole point of this is to simply compare vehicle efficiencies in an apples to apples way not perfectly predict what you’ll actually experience driving the car.
There’s no scandal here just sensationalism.
Why are people so bizarrely defensive about this?
This isn’t sensationalism. It’s a scientific study of actual real-world fuel use based on data from thousands of vehicles (at least ten thousand, I assume, based on earlier studies). If, as the study author says, internal combustion engines are being used more frequently than estimated, should it not be addressed? Should we not be aiming for higher efficiency in these vehicles? If tests aren’t accurately predicting usage, should we not develop more accurate tests?
Its not defensiveness it’s just recognizing the issue for what it really is. You can change the estimation calculation all you want, but it will always be wrong because the variables being used don’t blend together well. You can make gas engines that get 100MPG or even 1000MPG but it won’t make for an accurate estimation when averaged out with ∞MPG or 0GPM.
That’s a problem with the estimation not with the manufacturers. The manufacturers tell you exactly what the electric range is and also what the ICE fuel economy is. It’s trivial to apply these values to your driving habits to get an estimation for your use case.
As an example, I’ve been eyeballing the Prius PHEV with its 44 mile range (and 47MPG hwy). My commute is about 45 miles each way and I have access to chargers at work, so my daily fuel consumption would either be 0.04 gallons (charge at home and work) or 1 gallon (charge at home only) giving a 2400% variation in fuel economy for the exact same trip based solely off my actions alone, having absolutely nothing to do with the car itself.
Here you’re conflating two separate issues and highlighting exactly why people are calling this misleading. You can change the calculation all you want but that isn’t changing the efficiency of these vehicles and this study doesn’t demonstrate that these vehicles are inefficient. All it shows is “your MPGe or l/100km is greatly effected by how often you stay on electric power” and that factor is solely dependent on the driver and ranges from near zero to infinity regardless of the vehicle chosen.
It doesn’t get more accurate. We should just scrap the combined “MPGe” (and EU equivalent) and stick with “electric range” and “MPG”. Both of those can be fairly accurately predicted as separate values. How they combine is entirely up to the individual.