Consumer Reports tests fuel efficiency vs. speed; Honda Insight biggest loser
2010 Honda Insight - Click above for high-res image gallery
The faster you drive, the more fuel you use. Common sense, right? Absolutely, but it's still helpful to see real-life data, as you'll see by checking out the results of a recent test performed by Consumer Reports. Not all cars perform the same at various speed limits, and as you might expect, America's most fuel efficient models are also the vehicles most affected by higher speeds.
A total of seven vehicles were tested by CR: a Acura TSX with a 2.4-liter four-cylinder; a new 2010 Honda Insight; a Lexus RX350; a Mercury Mountaineer with 4.6-liter V8; Toyota Camry and RAV4 with 2.5-liter four-bangers; and a Yaris with a 1.5-liter four.
As you're probably aware, today's hybrids are optimized for high fuel economy at city speeds and therefore lose much of their miserly ways on the highway. As it turns out, this was especially true of the new Insight hybrid, which lost over 15 miles per gallon moving the needle from 55 mph to 75 mph – the largest drop in the contest. Click here for the complete test results.
Gallery: 2010 Honda Insight
[Source: Consumer Reports]
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Reader Comments (Page 1 of 4)
Turbofrog 4:07PM (9/10/2009)
Maybe it's just me, but this headline seems like a pretty funny take-away from that story. Yes, it's true that the Insight lost the most efficiency in absolute terms, but the fact remains, it was still 8% more efficient than any other vehicle in the test.
Besides; the marginal difference in efficiencies between vehicles shrank, but almost all of them lost a similar amount when you look at percentage values. Of course the Insight is going to lose the most mpg, because it has by far the highest mpg to begin with.
Silly reporting, Autoblog.
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StanleyVanBuren 4:11PM (9/10/2009)
great, encourage more Insight drivers to do 55mph on the freeway. just what we need...
akboss302 4:17PM (9/10/2009)
Re:Stan,
I have no problem with cars doing 55 on the freeway, as long as they are intelligent enough to be in the right lane. Go as slow as you like, the benefits are clearly detailed in this article.
IK 4:29PM (9/10/2009)
75 mph ?!
what would Hillary say ?!
audi_arena 4:55PM (9/10/2009)
Thank you akboss!!
banana2011 5:08PM (9/10/2009)
Here's a spreadsheet i made to show how much we can save between high/med/low mpg cars driving @ diff speeds.
http://i25.tinypic.com/11tls2e.jpg
banana2011 5:11PM (9/10/2009)
the conclusion should be "every extra hour lost on the highway" instead of "every hour"
So if you make less than the potential savings - drive slower and stay to the right
James Sonne 5:13PM (9/10/2009)
http://jsonne.blogspot.com/2008/08/why-america-doesnt-want-efficient-cars.html
I did the calculations of price vs. mpg a year ago, and that relationship is nonlinear, similar to the relationship we see in this Consumer Report's article. Anyway, I have driven 55 mph on the interstate in my Acura RSX and achieved 42.5 mpg. If I go 75 mph I get about 32 mpg.
In city traffic, I find it interesting to note that I get better gas mileage if I accelerate quickly by bringing the engine into the sweet spot of its power band and then cruising. Of course, this seems to fit with the idea that energy usage is the integral of power with respect to time. There's a balance in with each engine that gets you up to speed to cruise efficiently while using the least amount of energy to do it. I think BMW decided that a heavy foot and short shifting it in their torquier engines is better in their cars.
daleam 10:09PM (9/10/2009)
Yet when the same logic is applied to vehicle sales, companies like Kia and Subaru are praised for their percentage increases in sales, while even the lowest selling American company, Chrysler Co, still sold more than twice the number of vehicles last month than either of these Asian brands and even "worst performing" General Motors outsold everyone and still maintains the position as number one in the US and Ford Co is doing quite well also.
Jeff McNeil 4:08PM (9/10/2009)
"That’s a drop of about 5 mpg for every 10 miles over 55. Vehicles with lower fuel efficiency had the smallest drop. The V8-powered Mercury Mountaineer has a fuel economy of 23.8 mpg at 55 mph and that drops to 21.2 mpg at 65 and 17.8 at 75 mph."
Wouldn't this chart be entirely more useful if it reported % of fuel economy lost at each 10mph increment? This way we can compare how much efficiency is lost in the Mountaineer verses the Camry. By my calculations both vehicles lose between 25-27% in mileage at 55-mph verses 75-mph.
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homunculus 4:08PM (9/10/2009)
the insight is still much more fuel efficient than all of the other cars at any speed.
the "biggest loser" is still the winner.
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Mike 4:14PM (9/10/2009)
LOOK AT THE % people NOT THE MPG!
Its the same thing people have to do when looking at a Civic Hybrid Vs a Standard Civic.
If you can average 35 mpg in a civic and 43 in a hybrid thats a savings of 23%
If you increase a TRUCK 8mpg. From 15 to 23. Thats a 65% savings.
Same thing holds true for a REVERSE.
A 23.8 mpg car that goes down to 21.2 is an 11 % decrease.
Insight - 51.9 down to 44.8 is 13.5% decrease. Althought the 7mpg looks much greater.. its still very clos in the %.
Acura TSX - 39.9 mpg down to 35.5mpg is also 11.1% decrease.
Rav 4 - 34.6 mpg down to 29.3 is actually the biggest looser at 15.3%!!
come on.. how are these editors really paid for this stuff???
I'm FAR from an engineer etc.. but come on people.. look at the %! It's going to cost the Rav4 guy MUCH more.
It already 33% more for fuel.. now its going to be more like 38% more in fuel costs with increasing speeds.
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Rich 4:49PM (9/10/2009)
Okay:
car %age loss absolute loss
TSX -23.06% 9.2
Insight -29.67% 15.4
RX350 -25.57% 7.9
Mountaineer -25.21% 6
Camry -26.05% 10.5
RAV4 -25.14% 8.7
Yaris -20.00% 8.6
It's pretty clear still: the Insight's absolute *AND* percentage losses when driven hard are greatest, simply because it has most to lose.
I mean, that was pretty clear from the article. However, the *spirit* of the article is to slam the Insight. Which the figures simply don't support.
CH 6:35PM (9/10/2009)
No, Mike. Neither the absolute nor percentage change in mpg is the ticket. What you should look at is the change in fuel consumption; i.e., gallons/100 miles:
Additonal gallons/100 miles at 75 mph versus 55 mph
Yaris 0.59
TSX 0.75
Insight 0.81
RX350 1.11
Mountainer 1.42
Typesbad 4:13PM (9/10/2009)
Biggest loser? Technically yes, but then it did have the most to lose, having by far the best mileage at 55 and still had the best mileage of the grouping at 75. Its performance versus the Yaris is particularly impressive.
The winner in this little contest to me is the insights upscale cousin. TSX. A very satisfying luxury-sport sedan getting over 30 mpg even at a steady 75? Not bad.
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USCGTO 4:14PM (9/10/2009)
lol.. not that it matters, but,
My 6.0L GTO gets me better mpg as I approach 80 or so as compared to 50...lol I
It touches 26 almost.
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tfsjake 4:34PM (9/12/2009)
Pretty sure that's wrong, unless your in the next to top gear at 50 and in the top gear at 80.
zamafir 4:15PM (9/10/2009)
Now TDIs? The whole reason they dominate in europe is they pretty perky and get great economy. Maybe that's why it was left out?
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Rich 4:53PM (9/10/2009)
At 55, I get about 44 mpg.
At 75, I get about 39 mpg.
This is in a 1999 MkIII Jetta, not maintained as best as I should. I should borrow my mate's gadget so I can monitor it in real time while trying to keep my good eye on the road.
zamafir 5:54PM (9/10/2009)
sounds about right, i've done several trips to Cal from UCSD in an MkIV TDI and have seen the same. I'm sure the MkV would do just as well, which is why it's a flagrant and silly omission from this test, as a diesel would, obviously, beat all. We've known nothing trumps diesel for highway economy for how many decades now?