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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

#191

Post by TylerE »

userbinator wrote: post #166
bonzini wrote: post #118

Earlier quoted context omitted.

No matter how careful I am, it's hard for me to get lower than 130% of the fuel consumption reported by the manufacturer. Perhaps I can do 120% of the reported consumption at 90 km/h, but I can hardly get lower than 140% on the highway (130 km/h) and in city traffic.

Are you in an area with much hilly terrain? That'll definitely increase fuel consumption significantly.

Actually, it depends. Modern cars do better in rolling hills than on perfectly flat land, since they can cut fuel entirely on the downhill, and the climbs don't require that much extra fuel over just maintaining speed.

Now, mountains are another story, of course.

Some good stuff in this SE question: http://physics.stackexchange.com/questions/6220/can-a-car-ge...

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

#192

Post by emp_zealoth »

mfringel wrote: post #157
001sky wrote: post #141

Earlier quoted context omitted.

They didn't call those bands "rage against the machine" and "public enemy" for nuthin now did they? I mean, in all seriousness, why be so serious? Simple points need to be understood, not simply dismissed out of hand. In theory everything the government or your employer tells you is true. In reality, they have alot to gain from asymetric information distribution, both in terms of negotiating financial outcomes but al…

Have you checked your keyboard's electrical path for surveillance equipment this morning? Did you test your water for drugs this morning? Did you check them yesterday? We all live at certain layers of abstraction.

All you have to do is look at how much gas you put in the damn thing and divide by how much youve driven since you last topped up. Not a deep investigative effort

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

#193

Post by enraged_camel »

ticktocktick wrote: post #103
vkjv wrote: post #86

Earlier quoted context omitted.

I thought the same. In my anecdotal experience, drivers tend to get much lower than the manufacturer mileage because they optimize for things other than fuel economy (e.g., speed). My dad taught me lots of tips on conserving fuel and thankfully I've exceeded the sticker numbers on every car I've owned.

Just stay off the brakes as much as possible. No big secret really.

Unless your car has regenerative breaks, in which case you should randomly and unpredictably break to generate free energy.

edit: downvoters are once again proving that HN doesn't get jokes.

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

#194

Post by protonfish »

lucaspiller wrote: post #172
kwelstr wrote: post #138

Earlier quoted context omitted.

And when in the highway don't go too fast, speed increases drag etc. etc.

I did some tests on a long drive last week, for the Smart Forfour I had this was the fuel consumption. It was all along flat, straight parts of the highway. Reports were based upon the cars own fuel efficiency monitor. - 135 km/h 7.8l/100km (30 mpg) - 125 km/h 6.5l/100km (36 mpg) - 115 km/h 5.4l/100km (43 mpg) I never realised speed made such a difference! (Mpg is US gallons)

That's

- 84.0 mph

- 77.5 mph

- 71.5 mph

For us in the states.

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

#195

Post by superuser2 »

mattlutze wrote: post #58
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...

The source of the data is actually www.spritmonitor.de, which is a self-reporting mileage tracking site (like www.fuelly.com). With ~501k vehicles tracked and 8.885B kilometers tracked, the site represents ~17k kilometers per car of user-reported mileage information. Is this the best, or a reliable source, of information to start the reckoning/witch hunt to come? I'm not sure.

For starters, the average person probably drives a great deal more aggressively than the fuel-economy ideal. At least, the automotive industry is convinced enough of this to install behavior-modification techniques like "eco scores" into dashboards.

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

#196

Post by emp_zealoth »

trymas wrote: post #46
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.

Yup. Diesel cars can pull of 5l/100km quite easily (even VW Passat from 1998 can do that). My diesel Skoda Fabia consumes 4.6l/100km at 90kmh in highway. If conditions are not terrible, I hover around 5l/100km on average in mixed conditions (city and highway). Though few major traffic jams can ruin statistics pretty badly. Also in winter average is about 5.6l/100km. Maybe /user/emp_zealoth had petrol cars in mind? I'…

Yes, i was talking about gasoline ones, diesels can and do get lower fuel consumption

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

#197

Post by VLM »

bisRepetita wrote: post #92
mattlutze wrote: post #58

Earlier quoted context omitted.

The source of the data is actually www.spritmonitor.de, which is a self-reporting mileage tracking site (like www.fuelly.com). With ~501k vehicles tracked and 8.885B kilometers tracked, the site represents ~17k kilometers per car of user-reported mileage information. Is this the best, or a reliable source, of information to start the reckoning/witch hunt to come? I'm not sure.

The interesting part is that the difference increased from 2001 to today.

Increased use of ethanol gasoline?

The official .gov propaganda is a 3% penalty, but self reports vary from 5% to 15%. E10 is a thirsty fuel and people buy a lot of groundwater at gasoline prices, which likely accounts for some variation.

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

#198

Post by enriquec »

fluxquanta wrote: post #114
awjr wrote: post #107

Ok let's be real here, if we put the "pollution" taxes onto fuel and not on the design of the car, this problem, in effect, goes away. There is still the issue that high efficiency, usually means running the engine at high temperatures which generates far more NOx gases. We should be taxing the amount of fuel used.

Additional fuel taxes are typically not a welcome change among the pubic. I agree that logically this is what should be done, but everyone fills up their gas tank every few hours/days/weeks and sees that price. People only buy new cars every once in a while, and they expect a large purchase price. I think psychologically taxing the vehicle and not the fuel is more of a people pleaser.

And yet, todays weighted average tax for the US is $.4888 per gallon (54.50 for Diesel). Today's national average price of $2.28 puts that at ~21.4%. That probably puts gas up there with one of the most taxed things I buy.

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

#199

Post by MattBearman »

cannedbass wrote: post #112

So how many of these cars have turbos? I know the BMWs at least are mostly turbo 4-cylinders. The whole reason manufacturers are moving to small displacement turbocharged engines over large displacement naturally aspirated engines is because the EPA MPG tests never run the engine in a range where the turbo is doing much. Put the car in the real world and the driver's lead foot makes the turbo kick in, killing fuel ec…

My thoughts exactly. And I don't think it's just lead footed drivers, the lag on some of these small turbo charged engines is so great that most drivers will feel they have to stamp their foot to the floor just to make the car move.

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

#200

Post by yoz-y »

Bud wrote: post #82
cLeEOGPw wrote: post #65

Earlier quoted context omitted.

> except electric Why? You have just been shown corporate cheat on tests. Why you would ever assume this has something to do with fuel type? I expect Tesla cheat as much as MB or BMW in their "range" test. And if you believe otherwise you are just someone who doesn't learn from his experience.

You "expect"? Could you perhaps cite any data, any at all? It's not like we don't have a LOT of Tesla owners out there who are obsessively testing this, every day. Do you think they're just all part of the conspiracy?

It is kind of weird that this is surfacing just now. There are magnitudes more VW owners than Tesla. Why have not the consumer studies revealed this a long time ago?
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