<![CDATA[Grist - Comment Feed for Inflated fuel efficiency ratings for Canada’s cars]]> Grist Comment Feed en Comment #1 by spaceshaper http://www.grist.org/article/are-canadian-car-buyers-getting-sold-a-bill-of-goods/ Wed, 12 Nov 2008 22:19:10 -0800 http://www.grist.org/article/are-canadian-car-buyers-getting-sold-a-bill-of-goods/1 But what's the reality?

Eric, it would be helpful if you included your real-world experience with your Civic as a reference point. The EPA numbers for the Toyota Yaris which I drive (29/36) are considerably different from my consistent driving experience with the car (34/38) over an 18-month period. It's almost tediously predictable - I do most of my driving in town, and every 340 miles the gas gauge starts to blink and I put in 10 gallons before the pump clicks off.

The Canadian figures are much closer to my experience than the EPA's, though still an underestimate (32/39 if my math is correct). I drive conservatively around town but probably faster than I should on the highway which may account for the difference. I know it's all relative when we're making choices between vehicles based on these estimates, but it's hard to come to the conclusion, in my personal example at least, that Canadian Yaris drivers are being ripped off or mislead. More like the US EPA has some 'splainin to do.

BTW, I totally agree that L/100km or Gal/100m is a far less misleading metric.

The true meaning of life is to plant trees, under whose shade you do not expect to sit.

]]> But what's the reality?

Eric, it would be helpful if you included your real-world experience with your Civic as a reference point. The EPA numbers for the Toyota Yaris which I drive (29/36) are considerably different from my consistent driving experience with the car (34/38) over an 18-month period. It's almost tediously predictable - I do most of my driving in town, and every 340 miles the gas gauge starts to blink and I put in 10 gallons before the pump clicks off.

The Canadian figures are much closer to my experience than the EPA's, though still an underestimate (32/39 if my math is correct). I drive conservatively around town but probably faster than I should on the highway which may account for the difference. I know it's all relative when we're making choices between vehicles based on these estimates, but it's hard to come to the conclusion, in my personal example at least, that Canadian Yaris drivers are being ripped off or mislead. More like the US EPA has some 'splainin to do.

BTW, I totally agree that L/100km or Gal/100m is a far less misleading metric.

The true meaning of life is to plant trees, under whose shade you do not expect to sit.

]]> Comment #2 by Sam Wells http://www.grist.org/article/are-canadian-car-buyers-getting-sold-a-bill-of-goods/ Thu, 13 Nov 2008 01:08:19 -0800 http://www.grist.org/article/are-canadian-car-buyers-getting-sold-a-bill-of-goods/2 Driving Cycles

SpaceShaper brings up a valid point that the crux of the matter is the driving cycle used in the testing - whether the cycle replicates the "average" car driving in the population and whether you as a driver follow that cycle.

The old EPA mileage test was based on what we used to call the "Grandma Test." The acceleration forces were very gradual and smooth, with a section at slower speeds (city driving) and higher speeds (highway driving).  

The newer test incorporates "real world" information from instrumented vehicles that shows the drivers are much more aggressive than Grandma. Therefore, accelerative forces were increased - which had the effect of lowering fuel economy and raising emissions.

So it is all in that silly driving cycle used in the laboratory dynamometer tests. I used to drive vehicles for some of those kinds of tests - for grins - and it was quite hard to stay within the speed ranges without an "excursion" that would invalidate the test. That indicates even more human error - right there in the lab!

There is no such thing as perfection in this game, and one test is no "better" than another. A minor case of road rage can blow your numbers all to heck.  -sammie

Onward through the fog

]]> Driving Cycles

SpaceShaper brings up a valid point that the crux of the matter is the driving cycle used in the testing - whether the cycle replicates the "average" car driving in the population and whether you as a driver follow that cycle.

The old EPA mileage test was based on what we used to call the "Grandma Test." The acceleration forces were very gradual and smooth, with a section at slower speeds (city driving) and higher speeds (highway driving).  

The newer test incorporates "real world" information from instrumented vehicles that shows the drivers are much more aggressive than Grandma. Therefore, accelerative forces were increased - which had the effect of lowering fuel economy and raising emissions.

So it is all in that silly driving cycle used in the laboratory dynamometer tests. I used to drive vehicles for some of those kinds of tests - for grins - and it was quite hard to stay within the speed ranges without an "excursion" that would invalidate the test. That indicates even more human error - right there in the lab!

There is no such thing as perfection in this game, and one test is no "better" than another. A minor case of road rage can blow your numbers all to heck.  -sammie

Onward through the fog

]]> Comment #3 by mihan http://www.grist.org/article/are-canadian-car-buyers-getting-sold-a-bill-of-goods/ Thu, 13 Nov 2008 02:14:31 -0800 http://www.grist.org/article/are-canadian-car-buyers-getting-sold-a-bill-of-goods/3 climate differences

You would generally expect Canada's efficiency to be somewhat lower since it is generally colder, and fuel efficiency decreases with temperature.

]]> climate differences

You would generally expect Canada's efficiency to be somewhat lower since it is generally colder, and fuel efficiency decreases with temperature.

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