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

2016 Prius 20% improvement in MPG?

Discussion in 'Gen 4 Prius Main Forum' started by iplug, Sep 10, 2015.

  1. civicdriver06

    civicdriver06 Active Member

    Joined:
    May 27, 2009
    797
    324
    0
    Location:
    Germany
    Vehicle:
    Other Non-Hybrid
    US EPA ratings are far more realistic than European and especially Japans fuel efficiency rating !
     
  2. mozdzen

    mozdzen Active Member

    Joined:
    Jan 17, 2011
    719
    295
    0
    Location:
    Phoenix
    Vehicle:
    2015 Tesla Model S
    At what point, mpg speaking, will further gains be uninteresting? at 15,000 miles per year (100,000 miles takes 6.66 yrs (350 wks) to achieve)
    100,000 miles at 50 mpg = 2,000 gallons or ~ 200 fill-ups or once per 1.75 weeks
    100,000 miles at 57 mpg = 1,750 gallons or ~175 fill-ups or once per 2.00 weeks % mpg increase over 50 mpg = 14%
    100,000 miles at 67 mpg = 1,500 gallons or ~150 fill-ups or once per 2.33 weeks % mpg increase over 57 mpg = 18%
    100,000 miles at 80 mpg = 1,250 gallons or ~125 fill-ups or once per 2.80 weeks % mpg increase over 67 mpg = 19%
    100,000 miles at 100 mpg = 1,000 gallons or ~100 fill-ups or once per 3.50 weeks % mpg increase over 50 mpg = 25%

    Of course, 100 mpg would be awesome, but to think we could have 4 more generations above Gen III with each next generation achieving hefty increases in mpg will require something other than gasoline. Filling up once per month is really nice. After gen IV, I don't see further gains without significant use of the electric motor, powered by either a battery or fuel cell.

    food for thought.
     
  3. cyclopathic

    cyclopathic Senior Member

    Joined:
    Apr 15, 2011
    3,292
    547
    0
    Location:
    2014 Prius c
    Vehicle:
    2010 Prius
    Model:
    II
    I it is hard to disagree with hard numbers, though some will try.

    Per "C" counter I am burning ~50gal/mo (46-49 to be precise). 20% bump in MPG would save 8.5gal/mo. Even with prices going back up to $5/gal this would cost $42.5/mo. Not enough to cover new car payment. If indeed Gen4 is rated at 55MPG and Eco at 60MPG with current prices we are looking at <$10/mo diff btw Gen3 vs 4 and Gen4 vs Eco.
     
  4. iplug

    iplug Senior Member

    Joined:
    Mar 21, 2012
    2,447
    1,695
    0
    Location:
    Rocklin, CA
    Vehicle:
    Other Electric Vehicle
    Model:
    ----USA----
    No, among several other things, one loses credibility with ad hominem attacks that have to be moderated, then going back and re-editing one's posts significantly after another has replied. We'll also ignore bad spelling and grammar that many (including self) are guilty of.

    At current U.S. gasoline prices it is hard to make an argument for upgrading to a gen 4 Prius from gen 3 on personal cost benefit alone. Doubt this would happen any time soon, but with higher oil prices and/or taxation on the order of 2-10x net increase, that would make it more of a personal cost benefit consideration. Agree filling up less/extended gasoline range is a plus.

    Other things to consider are continued reduction in transportation carbon footprint, no direct cost/subsidies from tax-payers, reduced pollution, seating/cargo capacity, etc.
     
  5. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    44,822
    16,059
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    The gearing is shorter (shorter final gear ratio) on the v to allow reasonable acceleration. That will contribute to the lower mpg as well.

    That has changed a few years ago. Toyota Canada and Honda Canada both list multiple L/100km numbers for each model if there's something different (e.g. larger wheels or different engine). So the Corolla CE, LE, S and LE Eco have different numbers (and the LE Eco has two ratings depending on whether you have the 15" or 16" wheels), the Civic and Fit have different numbers too depending on model.
     
  6. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,981
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    Does the current Prius get listed with the 17" wheels separate from the 15" wheels? We -know- the mileage is different between the two. I haven't seen two listings for them.
     
  7. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    21,700
    11,302
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    Not in the US.
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
  9. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,981
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    So is Toyota in trouble? Is the VW fiasco going to cause whomever to look more closely at the "self testing" done to date? Toyota listed the -best- mileage of the models offered as the mileage of -all- the models. Less dishonest than VW, but still not really telling the truth?
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    The current mpg ratings are not that far off the mark, a LOT closer to reality. What's it: roughly a 5/4 bump in the liters per 100 km, compared to the old method:


    Capture.JPG

    Ours has the 17" rims, and Michelin Pilot HX MXM4, and these are the last few tanks. We're trying, but not nuts about it:

    Capture.JPG
     
  11. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    21,700
    11,302
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    No, because everybody uses the best figures for the CAFE/window sticker here.
     
  12. cyclopathic

    cyclopathic Senior Member

    Joined:
    Apr 15, 2011
    3,292
    547
    0
    Location:
    2014 Prius c
    Vehicle:
    2010 Prius
    Model:
    II
    No they use their best highway rating in ads.
     
  13. ydooby

    ydooby Junior Member

    Joined:
    Apr 13, 2011
    29
    32
    0
    Location:
    CA, USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Guys.. Nikkei News already reported the full details of the Eco model:
    Google Translate

    Basically the Eco model is nothing but a stripped, barebone, cheap entry-level Prius, with a 50kg lower weight (1310kg vs 1360kg) than the regular Prius by having a smaller fuel tank (38L vs 43L), a smaller washer tank (2.0L vs 4.8L), less speakers (4 vs 6), no rear stabilizer and no tonneau cover. It's rated at 40km/L in the JC08 cycle while the regular Prius gets 37km/L. The 3th-gen Prius currently does 32.6km/L in JC08, which means the fuel economy of the Prius Eco is a (40 - 32.6) / 32.6 =~ 22.7% improvement over the current Prius in the JC08 cycle.

    A better summary of each model grade can be found here:
    Google Translate

    A 20% improvement in the EPA rating, from 50mpg to 60mpg, therefore, may not be that far-fetched, IMHO.
     
    #73 ydooby, Sep 22, 2015
    Last edited: Sep 22, 2015
    iplug and Sergiospl like this.
  14. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,018
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    No way removing 50kg alone takes you from 37km/L to 40km/L. If it did, every person that got in the car would reduce your mileage by 10%!
     
  15. ydooby

    ydooby Junior Member

    Joined:
    Apr 13, 2011
    29
    32
    0
    Location:
    CA, USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Well the Eco model will also be missing the LED fog lights, smart entry, synthetic leather steering wheel and rear seat center armrest found on the regular model. But you're right that 50kg alone should not give a 3km/L boost. I suspect that the Eco model will get even smaller and thinner wheels, for example.
     
  16. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,686
    48,936
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    weight won't change things much, but i like the idea of a stripped down version for those on a budget, and to fend off competition.
     
  17. cyclopathic

    cyclopathic Senior Member

    Joined:
    Apr 15, 2011
    3,292
    547
    0
    Location:
    2014 Prius c
    Vehicle:
    2010 Prius
    Model:
    II
    Don't hold your breath. Prius C/Aqua is rated 37km/L on JC08 but barely even to Gen3 on EPA.

    JC08 does not account for engine warm up and rates fuel economy for speeds under 60km/h or 38mph. If you keep speed under 40mph, 68-72MPG is a norm in C, but in regular extra-urban cycle it barely matches Gen3. Most of the improvements at lower speed is due to lower weight. Also JC08 does not stress battery, so lower capacity battery (what is mainly culprit of C) and lower brake recovery does not come into effect.

    I would expect that on EPA test cycle difference btw Gen4 and Eco will be less than 1MPG.

    EDIT: does this mean that Eco is equivalent of Prius One when Gen3 was released??
     
    Trollbait likes this.
  18. Maxwell61

    Maxwell61 Active Member

    Joined:
    Apr 10, 2012
    384
    238
    0
    Location:
    Italy
    Vehicle:
    Other Hybrid
    Model:
    N/A
    I hate to say "i've said that". One thing is increasing FE using technology, other thing is stripping barebone. ECOnomic.

    Changing the stock 17" Dunlop Fast response with the TOYO Nanoenergy 2 A-class on my Auris, i've got about 12% improvement in FE, and similar figures has been achieved on a german car magazine testing, and validated by some few owners of Prius 2 and 3 and Auris ( all with different Toyo Nano2 sizes) on our forum.
    So, really look for tires and the mystery disappear...

    As for the 15"-17" different FE (un)declared by Toyota: unlike in US, in EU we have differentiated official figures: about 6% better FE for the quite conventional Auris-Prius 15" tyres. Choose a low rolling resistance tyre, and 10% improvement for a 15" RR relative to a conventional 17", is not even a good number, a 15" A-class should give much more.

    So, can i say i'm really unimpressed by claims of 10% FE improvement?
     
  19. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    44,822
    16,059
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    No it does not. It's possible because the Prius is listed as a single model with multiple packages as opposed to different trim levels (which is probably why Toyota Canada listed the Corolla LE Eco and Corolla LE Eco Technology as different trim levels to let them list the different mpg numbers as opposed to listing just the 15" numbers and called the "Technology" a package like it does on the S and LE models).

    So the question is, "Is Toyota hitting a wall for improvements in mpg with current technology?" I suspect the Gen 5 will need a weight reduction to hit 60mpg combined without an Eco model. Use of CFRP or even more aluminium (monocoque?) to get the weight down to 1,300kg. In the other thread, the Prius S and Prius A models are listed at 1,360kg and S E-Four and A E-Four models at 1,430kg and 1,440kg. That rear motor and wiring is worth at most 70kg (the extra 10kg in the A is probably extra equipment).

    For reference, that E-Four model weighs about the same as a Prius Five (US) or Prius w/ Technology Package (Canada) and the "S" is a midgrade model.
     
  20. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,686
    48,936
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    you can say it, but in actuality, 10% is very impressive, considering where toyota mpg's are compared to the rest of the world.