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Study: Some car models consuming around 50% more fuel than official results

transportenvironment.org

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Re: Study: Some car models consuming around 50% more fuel than official results

#121

Post by JoeAltmaier »

outworlder wrote: post #113

So, does that mean that all those armchair discussions about the merits of ICE and electric cars with "official" mileage numbers thrown about are completely invalid? A 50% increase in fuel completely changes the cost proposition.

I'm not so sure. Especially for high-end cars, lifetime fuel costs are dwarfed by the car cost. Even in low-end high-mileage cars, both numbers are smaller but the car cost is still probably double the lifetime fuel cost. So maybe across the board we can expect fuel not to be a driving variable in the cost proposition?

Re: Study: Some car models consuming around 50% more fuel than official results

#122

Post by JoeAltmaier »

_ambigu0us_ wrote: post #105
tonylemesmer wrote: post #33

Earlier quoted context omitted.

The travel from a single pedal press is small, but its probably a solvable problem. It just needs a different design.

It's an interesting one certainly, it sort of comes down to mechanics at the end of the day. In the event of a catastrophic, complete electrical/engine failure, the driver needs to be able to apply enough braking force to stop the car in a sensible distance using their leg muscles. This places an limit on the travel distance of the pads for a full press of the pedal. Indeed, most cars use a servo that uses vacuum 'pr…

I think they have direct mechanical linkages because the law says they must. Otherwise many manufacturers would gladly forego all safety issues for profit. A clear public win via govt regulation.

Re: Study: Some car models consuming around 50% more fuel than official results

#123

Post by petercooper »

I never pay attention to fuel consumption figures as they have never represented reality in my case. My current Mercedes has an official rating of 40mpg, but I never get that out of it unless I literally sit at 55mph on a flat motorway and never change speed (impossible in the UK). Some journeys I go as low as 19mpg when it's driven as it's meant to be. All the Vauxhalls I had before were the same.

Re: Study: Some car models consuming around 50% more fuel than official results

#124

Post by joosters »

One problem with the report is that real-world driving styles might be linked to the type of car. So, small cars might perhaps be more likely used for short commutes, whereas larger cars could tend to have longer motorway journeys. One driving style is likely to be closer to the standard tests than the other. So, even if one car seems to perform worse, it could just be because of the average driving of that car.

Re: Study: Some car models consuming around 50% more fuel than official results

#125

Post by pjc50 »

_pmf_ wrote: post #116
pjc50 wrote: post #9

Earlier quoted context omitted.

Europe has 'bet on diesel' for many years while hybrids have only recently become available.

All European manufacturers except Renault and BMW are hellbent on not offering attractive E mobility solutions, despite really expensive and extensive internal research programs. We in Germany have a large numbers of Smart cars in car sharing companies that are sponsored by Daimler, but it's not yet economically viable to actually buy an E-Smart (if you've driven one, it's not bad at all).

It's strange. Europe should be a better market for electric and hybrid cars, given the higher petrol costs, but I guess the high purchase costs are putting people off.

I'd buy one if I did enough miles. It's not worth it for a few thousand a year. Even having a petrol car sitting on my drive is an expense of marginal justifiability.

Re: Study: Some car models consuming around 50% more fuel than official results

#126

Post by on_ »

Bud wrote: post #29

If you read the full report, the automaker with by far the largest gap between its claimed improvements in fuel economy and its actual on-the-road performance is General Motors. Much worse than VW and Mercedes (who also did very poorly), by this measure. A reckoning is coming. source: see page 13, here http://www.transportenvironment.org/sites/te/files/publicati...

Wow. I thought about shorting GM, after the VW thing broke. I figured they would have the highest incentive to cheat and everyone is about to get caught.

Re: Study: Some car models consuming around 50% more fuel than official results

#127

Post by debacle »

Bud wrote: post #29

If you read the full report, the automaker with by far the largest gap between its claimed improvements in fuel economy and its actual on-the-road performance is General Motors. Much worse than VW and Mercedes (who also did very poorly), by this measure. A reckoning is coming. source: see page 13, here http://www.transportenvironment.org/sites/te/files/publicati...

US regulatory bodies have no teeth and we've already propped up GM once. The only reckoning that's coming is going to be another round of market jiggling, or maybe an unrecoverable failure.

Re: Study: Some car models consuming around 50% more fuel than official results

#128

Post by Cthulhu_ »

happyscrappy wrote: post #19
padelt wrote: post #11

Earlier quoted context omitted.

> Europe was really led astray when they were told that diesels were better for the environment Were we led astray? Or are we discussing the last few percentages beyond an actual advantage over gasoline engines?

The reason air pollution is so much worse in European cities than American ones is largely due to diesel passenger vehicles.

Also because US cities are much more sprawled, and are often organized in neat, efficient grids instead of having formed organically over the course of ~2300 years. Compare maps of Paris with any US city.

Re: Study: Some car models consuming around 50% more fuel than official results

#129

Post by Roboprog »

[deleted] wrote: post #34
mpweiher wrote: post #22

Earlier quoted context omitted.

I actually drove my Golf TDI at around the level of 5l/100km in Berlin for many years. Carefully. My girlfriend's Polo is significantly below that. Of course, these cars aren't ton and a half, but more around a ton.

[deleted]

And how.

My old '89 Chevy S-10 weighed just over 1700 pounds (770 kg) empty. At 55 MPH (90 kph) on the freeway (back when that was still the limit), it got about 30 MPG (13 km/l / 7.7l/100km). OK, not great mileage, but what do you want for 80s US car tech :-)

For safety reasons, or whatever, they don't make mini trucks in the US any more. I did a double take on a new Dodge "Dakota" in the store parking lot the other day. It looked just like a full size pickup as far as I could see.

Re: Study: Some car models consuming around 50% more fuel than official results

#130

Post by jsprogrammer »

Someone1234 wrote: post #91
crazypyro wrote: post #39

Earlier quoted context omitted.

"3. Deducting 4% from measured results Bizarrely the NEDC procedure allows carmakers to actually declare (use) a value 4% lower than the one measured. The provision is designed to minimize the testing burden but is being abused by carmakers to declare lower test results systematically." I wonder if there is a person that didn't expect this to happen.

Does it matter however when it is systematic? This is going to sound backwards, but consider this: People buy cars based in part on MpG, however MpG is within itself an abstract thing (i.e. you don't actually get X miles per gallon, never did, never will too many other factors to include). So if everyone removes 4% from an abstract number, the entire market has shifted down, but the relative difference between two mo…

The order/position may stay the same in your scheme, but the values do not retain their proportions relative to each other.

Presumably not everyone cheated the same, as well.

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