1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Your Mileage May Vary - Bad News for Hybrids

Discussion in 'Prius, Hybrid, EV and Alt-Fuel News' started by Widdletink, Mar 8, 2006.

  1. Widdletink

    Widdletink Member

    Joined:
    Feb 21, 2005
    218
    4
    0
    Location:
    Claremont, California
    Vehicle:
    2022 Prius Prime
    Model:
    LE
    <_< Hi Folks,

    I was crusing on AOL and ran across this article. For the benefit of those who are unable to access it, I have copied and pasted it below:

    Your Mileage May Vary
    Government to 'Adjust' Its Fuel Economy Estimates in '08
    By ERIC PETERS


    "Your mileage may vary" is the government's way of tacitly admitting the fuel economy figures it publishes on new car window stickers may not reflect the actual miles per gallon your vehicle will deliver once it’s in your hands.


    The figures are, at best, a rough guide -- not a definitive statement -- based on averages obtained during controlled testing. And as many of us have discovered, the government's estimates are often a tad on the optimistic side.


    The reason for the disparity between what the government thinks we might get and what we actually get is pretty straightforward: The way we drive our vehicles is often very different from the way government testers do. We cruise at 70-75 mph on the Interstate instead of 55 mph -- knocking down our potential "highway" fuel economy by as much as 5-10 percent. Or our typical "city" driving consists mostly of fairly abrupt (and very inefficient) 0-20 mph stop-and-go driving instead of steady-state 30-40 mph -- likewise reducing real-world "city" mileage by a significant margin.


    The current testing procedures used to estimate fuel economy date back several decades -- and haven't been updated to reflect changing driving habits and traffic patterns.


    For example, highway speed limits have gone up by 10-15 mph (or more) in many states, following the 1995 repeal of the 55 mph National Maximum Speed Limit (NMSL). These higher speeds have a (negative) effect on real-world highway fuel economy -- but the current tests assume we still live in a "drive 55" world. Similarly, congestion has worsened markedly in and around most major urban/suburban areas -- increasing the time we spend accelerating and decelerating (which wastes energy and thus fuel).


    Finally, the tests currently used are skewed because they assume "optimum" conditions -- even temperatures, intermittent use of power-drawing accessories such as air conditioning -- and so on. But cars burn more gas during "cold starts" on harsh winter mornings than they do at room temperature -- and constant cycling of the AC on a 100 degree July afternoon will likewise cut into the "best possible" mileage you might otherwise get.


    But new tests slated to go into effect beginning with model year 2008 vehicles should give consumers a substantially more accurate window into how much gas their new car or truck will use in real-world driving -- because the revised numbers will be based on more realistic driving patterns, including higher speed/higher load driving and more frequent use of power-using accessories such as air conditioning.


    The expected result of the changes in testing methods will be an "on-paper" drop in fuel economy of as much as 10-15 percent relative to currently published figures -- but this won’t reflect any actual drop in efficiency (all else being equal).


    There'll just be more truth in advertising.


    For example, under current tests, an '05 Chevy Silverado is rated at 17.8 mpg in city driving. Under the proposed revised testing system, the same vehicle's published city mileage would fall to 13.9 mpg -- which is probably a lot more in line with what the typical owner is getting. The Toyota Camry's projected city mileage would likewise drop from the current 28.5 mpg to a more realistic 24.2 mpg.


    One class of vehicles expected to take a major hit is hybrids -- whose "best case" fuel efficiency often founders on the shoals of real-world driving. The city rating of the Honda Civic hybrid, for instance, would drop some 12 mpg -- from the current 48.8 mpg to a much-less-spectacular 36 mpg. This will be a revelation (and reality check) for many people -- who drive their hybrids outside the envelope of the hybrid's optimal operating range.


    This isn't to say it's impossible to realize the best-case mileage your vehicle is theoretically capable of. If you drive very moderately (no rapid acceleration; no high-speed driving) under ideal conditions (no sub-zero cold starts, etc.) you might equal (or even beat) the government's currently published guidelines.


    But since few of us drive that way in the real world, it's probably a good thing the government is changing the way it does its testing. Better to know what we're likely to get rather than what we might get -- right?

    by Eric Peters AOL Automotive News

    Once I finished reading this all I could think was "well, here we go again". If you attended the recent OC Prius Club meeting you heard Dave Hermance discuss the proposed changes to the window sticker information currently available. He strongly urged us to read and review the suggested changes in format and weigh in on them during the current discussion period.

    One thing that the above reporter has missed (as usual) is that even with the downward adjustment of the numbers, our hybrids still far outstrip most other vehicles on the road. Also, even with the adjustment, the Prius would still meet the benchmark for the current regulation that allows us the carpool benefit here in California, that of 45MPG, since even with the adjustment in the numbers we would still come out at 48MPG City. I don't remember the exact math he illustrated, but I do remember the number.

    Also, another thing he pointed out (and this is really most important for our California owners) is that the carpool benefit is a "pilot" program and that we should be lobbying NOW for this to be extended beyond the scheduled 2008 cutoff date. I think it is quite right to assume that the possibility of this benefit's impact on traffic patterns having been fully studied and accurate conclusions drawn within the current time frame are probably slim and none. If we don't start pushing for the extension (at the very least) and permanent adoption of this plan now we may very well find ourselves shut out in a year.

    Take care all and have a super day,

    Tisza
     
  2. JackDodge

    JackDodge Gold Member

    Joined:
    Sep 22, 2005
    2,366
    4
    0
    Location:
    Bloomfield Hills, MI
    Vehicle:
    Other Hybrid
    It's always bothered me that a lot of drivers drive too fast and otherwise as inefficiently as possible so rather than figuring out what they're doing wrong and working to correct their driving habits to bring their mpg in line with the official numbers, they just say that the official numbers are wrong. Perhaps the official numbers could also include a second set of mpg projections. Call that set of numbers the if-you-drive-like-a-jerk fuel economy information.
     
  3. 2Hybrids

    2Hybrids New Member

    Joined:
    Sep 17, 2005
    565
    0
    0
    Location:
    Eustis, Florida
    Well, it is supposed to be the average....even if "average" means "jerk".. :D
     
  4. goodsam

    goodsam New Member

    Joined:
    Feb 6, 2006
    38
    0
    0
    Why can't they just say...this is the mileage you would get if you drive in a manner to achieve good mileage? I always get the numbers posted on the window sticker. People who don't get it should ask themselves "why" and be willing to change the way they drive if they want to get those numbers.
     
  5. dipper

    dipper Senior Member

    Joined:
    May 4, 2005
    1,242
    252
    0

    But... But... But...

    This is the land of the Free... Free to be stupid.

    Just look at the court decision and the lady in the McDonald's coffee lawsuit!!!!

    Even if they caused the problem, it is someone else's fault. :rolleyes:
     
  6. Dr Rocket

    Dr Rocket New Member

    Joined:
    Mar 6, 2006
    55
    1
    0
    I still get 44 mpg at 85 mph!
     
  7. Salsawonder

    Salsawonder New Member

    Joined:
    Nov 28, 2005
    1,897
    47
    0
    Location:
    La Mesa California
    Vehicle:
    2010 Prius
    Model:
    IV
    We know these things because our cars place the evidence of bad driving habits right in front of our eyes. We need to improve our driving skills so that our cars will perform to the best of their ability then we can brag about our mpg's, irritate our non-hybrid friends and just feel all that much better about having a cool car.

    Those that continue to waste fuel, speed, etc. don't want to see the evidence of what they do. They take pride in speeding ahead of us only to arrive at the same destination 60 seconds earlier. They like to bemoan the price of gas but continue their wasteful ways, buying cheaper cereal, turning down the heat to 65 in the house.

    :p
     
  8. KTPhil

    KTPhil Active Member

    Joined:
    Jan 14, 2005
    1,379
    20
    0
  9. darelldd

    darelldd Prius is our Gas Guzzler

    Joined:
    Jan 17, 2006
    6,057
    388
    0
    Location:
    Northern CA
    Vehicle:
    2006 Prius
    As usual, it is assumed that hybrids take a bigger "hit" with the new system (and between reality and the current sticker), when in fact there is no difference if you count it the proper way - percentage! Numbers mean very little, it is the percentage that counts, and it appears that the percentage difference is the same across the board, so why would hybrids be singled out as "losing more?"
     
  10. 2Hybrids

    2Hybrids New Member

    Joined:
    Sep 17, 2005
    565
    0
    0
    Location:
    Eustis, Florida
    One of the biggest features of the Prius is the ability to get higher fuel mileage than any other vehicle (except the Insight) - that's why hybrids are such an attention getting target for this subject.
     
  11. dipper

    dipper Senior Member

    Joined:
    May 4, 2005
    1,242
    252
    0
    But even the corvette got crampy mileage in the hands of Car and Driver. Car and Driver got 12mpg out of it. I think the EPA averages were something like 19/27. But no one complains because it is the corvette. And it does not sell paper when someone says corvette does not get EPA averages.. :rolleyes:
     
  12. dipper

    dipper Senior Member

    Joined:
    May 4, 2005
    1,242
    252
    0
    Wow. I still say bull. Stats can be turned into anything you want it to say. 700 cases in 10 years of reported coffee burns. How many cups of coffee did McDonalds served in ten years? :rolleyes: If McDonalds served 1 Million cup a day... that is 3.65 Billion cups of coffee. 700/3.65B = 0.0000192%. That is even less than the percentage of Prius died on the road.

    As for the lady, it is her fault to put the coffee between her leg.

    As far as hot coffee being too hot.... Any coffee shops can produce such hot coffee to due this damage. Maybe I should go to my company breakroom and pour some coffee on myself to make a few bucks. :unsure:

    It is a cause and effect. If we don't do the stupid thing to begin with, we should not be complaining about it at the end of the day. Either putting hot coffee on your lap, or driving a prius (any car) above 55mph as tested... and then go complain to others that it was not supposed to happen. ONLY IN AMERICA.
     
  13. EricGo

    EricGo New Member

    Joined:
    Apr 30, 2005
    1,805
    0
    0
    Location:
    Albuquerque, NM (SouthWest US)
    I had to take the car out for early (cold again :( ) driving today, and the tank mpg dropped below 67 by the time I returned home.

    DAMN the EPA.
     
  14. Allannde

    Allannde Just a Senior

    Joined:
    Jan 7, 2006
    874
    138
    0
    Location:
    Washington State
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    Look at the bright side. Now we will be able to brag at how we BEAT the EPA!
     
  15. jbarnhart

    jbarnhart New Member

    Joined:
    Jan 3, 2004
    629
    1
    0
    Location:
    Santa Clara, CA
    The only thing that really concerns me about the new EPA rules... I read somewhere that part of the new approach is to deduct some percentage of milage based on EPA's projections of how that car would fare in the "real world." In other words -- a vehicle-specific "fudge factor."

    If this is true, it opens up the EPA test to gross manipulation. It means we won't be able to accurately compare vehicles because some have higher others have lower fudge factors. I'm going out on a limb here, but I predict American car makers will suddenly appear to have much more competitive milage figures...
     
  16. DeadPhish

    DeadPhish Senior Member

    Joined:
    Sep 10, 2005
    2,010
    353
    0
    Location:
    Outer Banks of NC.. Retired to play golf and poker
    Vehicle:
    2005 Prius
    Model:
    N/A
    OK here is an alternate view :D to what seems like a back slap at hybrids. Most here will meet, or exceed by a large margin, the new EPA standards.

    Nothing will change in our individual results except that the 'EPA combined ratings' might be 44 mpg instead of 55 mpg. Nearly every Prius owner exceeds this rating even in winter.
     
  17. DaveinOlyWA

    DaveinOlyWA 3rd Time was Solariffic!!

    Joined:
    Apr 13, 2004
    15,140
    611
    0
    Location:
    South Puget Sound, WA
    Vehicle:
    2013 Nissan LEAF
    Model:
    Persona
    darrelld you are right, its all percentages. and hybrids will seemingly get hit harder because the mileage WILL drop more, but whether its 25 to 23 mpg or 50 to 46 mpg, its all the same, hybrids kicked butt before the change and will kick butt afterwards.
     
  18. jbarnhart

    jbarnhart New Member

    Joined:
    Jan 3, 2004
    629
    1
    0
    Location:
    Santa Clara, CA
    OK, I just read the preamble to the proposed rule change. It's as bad as I thought.

    The governemt makes its case by pointing to Consumer Reports and AAA and showing they they showed lower milage for hybrids. (Gov't can only afford bad statisticians I guess.)

    Next, they point out that they can change the actual tests themselves, since the U.S. laws are written around the CAFE standards, which are the basis of their numbers, too. So instead, they intend to cook the numbers by including results from the air quality tests.

    What are these tests?

    One simulates aggressive driving at 80 mph, with acceleration of greater than 8 mph/sec -- a figure our car can achieve only when floored. Another simulates 95 deg. high-humidity weather with the A/C on full blast.

    The plan is to revise the actual data (i.e. fudge) the fuel economy of each car based on its performance on these tests.

    In short -- the new window sticker is DESIGNED to "prove" that hybrids don't save gas.

    And we pay taxes for this!
     
  19. EricGo

    EricGo New Member

    Joined:
    Apr 30, 2005
    1,805
    0
    0
    Location:
    Albuquerque, NM (SouthWest US)
    I came to the same conclusions, jbarnhart.

    Testing that requires heavy engine loading -- even though such situations are rare for most driving by normal people. It isn't that Prius per se does bad in those situation, but that regular cars don't expose their horrible pumping losses which are present in 90% of daily driving.

    So the devil will be in the detail: how much will heavy engine load data be weighted ? If it is over 10%, an agenda is being dished out.

    The EPA has been gutted from the inside by bush appointees. Expect more garbage from that department.
     
  20. tripp

    tripp Which it's a 'ybrid, ain't it?

    Joined:
    Oct 23, 2005
    4,717
    79
    0
    Location:
    Denver, CO
    Vehicle:
    2005 Prius
    In the end if these tests are bogus they'll be exposed. Yes, it does sound like they're designing the test to help the otto cycle engine out. Of course the MPG for these cars will suffer too, especially the smaller engines that are going to have to work hard to hit the 8 mph/s. I wonder what the protocal will be for BSOC during these tests.

    Anyways, hybrids aren't going to go anywhere and as more people talk to those who own hybrids and hear that they're getting ~50 MPG (or perhpas better in future models) this will all fade into history as another example of human stupidity.