Hummer Greener Than Prius Urban Myth Exploded

Discussion in 'Toyota' started by Chuck, Apr 17, 2007.

  1. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Haole:

    ___Here is a peer reviewed little display you may be interested in? As weight and engine size increase, the numbers get far worse. The new Tundra’s LCA is an absolute joke by comparison to the Prius’ with the H2 having to be far worse :ccry:

    [​IMG]

    ___Good Luck

    ___Wayne
     
  2. wdb

    wdb semi-hyper

    [Dredging up the past, apparently.]

    I don't really see much "debunking" going on in the article linked in the first post. It's basically calling D2D's results into question by comparing their data to data from Toyota, which has an obvious and vested interest in making the Prius look good.

    I don't doubt that Toyota looks at total environmental impact over the life cycle of a vehicle, especially a vehicle as environmentally flashy as a Prius. However I do have a problem with people who assume that the CNW (D2D) study must be tainted or biased just because of the numbers its methods produce.

    Let me try to take subjectivity out of it for a moment: if Toyota really does care about total environmental impact, and/or if CNW really does use objective data -- for example if factors such as real-world miles driven are taken into account, which for the Prius should be heading higher, or if CNW really does amortize of development impacts over the now-larger number of vehicles sold -- then the D2D numbers for the Prius should change for the better over time. And they are. "Dust to Dust" dollars per mile for the Prius, from the two published reports I found from CNW, show the Prius numbers to be dropping pretty quickly:

    2005 $3.249
    2006 $2.865
    2007 $2.191

    In comparison: since Hummer sales have suffered so much lately, one would expect the D2D numbers for the Hummer to be getting worse. And they are. The numbers below are for the H3, which is the model that started all the hubbub (the H1 and H2 were always worse than the Prius, based on D2D figures):

    2005 $1.949
    2006 $2.069
    2007 $2.327

    I guess what I'm getting at is that CNW's data might bear watching over time, by folks truly interested in gauging the total impact of their automobile purchases. Such an approach seems far more practical than the shout-at-it-and-hope-it-goes-away approach that eco folks seem to want to give the ongoing study. From what I can gather about their methods and credentials, they sure do seem to be grounded in the real world I live in.
     
  3. Chuck

    Chuck just the messenger

    This study is saying the environmental impact of a vehicle shy of 3000 pounds has a larger environmental footprint than a vehicle weighing 8500 pounds....does that raise suspicons? It is what it is - propaganda. Spinella assumes a H2 will last 300,000 miles....something that happens to at most 1.5% of all vehicles and I doubt many of those are GM. He then says a Prius will last just 100,000 miles, yet a million Toyota hybrids and ten years later it's hard to find stories of Prius drivers that with wheels off at 100K...we have a member that drove a Prius I to 350K until a teen totaled it...there is a Brit Columbia taxi driver that has driven a Prius I to 250K, then Toyota took it for research while his Prius II is at 300-400K.

    Also suspicious is Spinella's estimates of the resources exceeding 15% to manufacture it relative to it's total life.

    The one billion of R&D was added to the cost of the Prius in the study....do you think Spinella would be as honest doing that to the Chevy Volt? ;)

    In conjunction with Dust to Dust is a British paper that took a horrendous moonscape picture of Sudbury in 1979 then deviously attempted to assert that the 0.4% of nickel Toyota buys for all it's vehicles are solely for the 20 pounds of nickel on a Prius traction pack and causing massive environmental damage. If this were true, cordless phones, cell phones, many other consumer electronics using NiMH batteries should be banned.

    It just amazes me how desperately people are to grasp at "proof" such as Dust to Dust to prop up flawed beliefs. Is it accurate to grace such as honest discussions?
     
  4. lightfoot

    lightfoot Reformed speeder

    That doesn't seem to be what is happening. CNW results are being questioned due to the assumptions and numbers that the study is starting from, not the numbers that result. This is very common scientific practice: it the results seem surprising, take a careful look at the assumptions and the numbers that they are based on, and the methods used to do the calculation.

    Frankly, even an unbiased analysis of something like this is fairly hopeless given the impossibility of accurately determining the true values of some of the large numbers involved. Probably not even Toyota can determine the true cost of developing the Prius because the technology and design for it probably drew on many different internal sources. And many of the costs (such as battery recycling) are imponderable until it actually happens for that model year car: to determine the D2D for a 2006 Prius, you have to wait until the car dies in say 2016 to find out what the actual recycling costs are for that vehicle. Messy.

    As for bias in the studies, there is always bias, for both Toyota and for CNW. I doubt if Toyota would fudge data (very embarrassing if detected!) but they might omit unfavorable aspects or present the data in a more flattering-to-Toyota way. CNW's motives are murkier. They are a studies-for-pay outfit, and we don't know who paid for this study (do we?). CNW's writeup can't be treated as science because (a) we don't know the sources of funding (scientific articles usually list the grants involved), and (b) it was not peer reviewed. Peer review certainly doesn't completely eliminate bias but it does reduce the problem.
     
  5. wdb

    wdb semi-hyper

    There it is in a nutshell. You don't like the results, so you find one point (among the 3,000 to 4,000 CNW claims to have considered in coming up with their figures) that can be considered odd, and leap headlong to your conclusion. That kind of 'analysis' really grates on the lab rat in me.
    Except for the H1, Hummers are Chevy pickup trucks. I have no trouble whatsoever believing that pickup trucks are among that sliver of vehicles driven for 30 years and multiple 100's of Ks. And in reading the CNW report (although I have not yet plowed through all 450 pages) they discuss things such as the impact of commonality of parts on their mileage and development figures; well, the 350 V8 in a Hummer is probably the single most common V8 on earth. So, yes, I can see where they came up with the number.
    All of which is why the numbers should be getting better, and they are.
    If that percentage is specific to the Prius, it will improve as more cars are produced and sold. If it is a generalization CNW used throughout the study, from what I've seen I have no doubt they have rational justification. As they like to point out (over and over), they were a year ahead of the feds in placing real world MPG for the Prius at 48MPG, which goes to the validity of their methods. Again, you may not like the number, but it becomes awfully hard to justify shooting the messenger when it turns out to be correct .
    Yes. I see nothing in their motives for producing the study (which to me seem obvious -- publicity for their company) to indicate that they favor one manufacturer over another. If that were the case, Audi must be their most hated company by far, because Audis really, really got slammed in the study.
    Sounds like yellow journalism at its finest. Whatever; I didn't see it and I'm not here to disucss it.
    That's just it; CNW did not start out to prop up anything. They went looking for studies comparing total lifetime energy impacts of vehicles, found nothing they considered to be truly thorough, and decided to do their own.

    Agreed. I'm attempting to have that discussion here. But the stuff I've seen so far as "refutation" of the CNW study hasn't measured up very well against the study itself in terms of scientific validity and built-in bias.

    I guess this is a good point at which to admit to a bias of my own: I'm biased towards believing that simpler, less complicated vehicles have less energy impact over their entire lifetimes than more complicated vehicles. I'm biased towards thinking that my Honda Fit has a smaller cradle-to-grave footprint than a Honda Civic hybrid. This is exactly why I went in search of numbers to prove (or disprove) my bias. And here I am.
    This is where I find my credulity to be weakest as regards D2D. But the company is in the business of doing just this kind of deep dive study, and so they have experience at locating numbers, access to the tools necessary to collect those they could not find, probably already had collected a bunch of the data for other studies, and could justify spending the effort to collect the rest because they could apply it elsewhere.

    To specifics: the fact that they went as far as to consider such things as how far auto factory workers drive to and from work may be thought of as downright strange, or it may seen as being thorough (perhaps to a fault?), or it may be seen as part of a truly honest attempt to determine the TOTAL environmental cost of a vehicle. That kind of thing is fodder for rational discourse, but I cannot see how it is justification to declare the study to be "junk science" and whatnot.
    Funny you should mention that. CNW uses that same example to point out how the numbers for hybrids are bound to change as their components are assimilated into the recycling stream.
    Statisticians the world over would beg to differ. :) However real world results should certainly be included as they become available, as CNW clearly states (and appears to be doing).
    CNW answers your funding questions directly in statements on their website; the study was self-funded, or as they put it, the employees paid for it by getting smaller raises. Based on what the company does to make money, I take them at their word.

    The D2D study became a great tool for bringing attention to their company, especially coming as it did in the midst of a growing dislike for FSP's in conjunction with the coming of age of hybrid vehicle technology. The timing was beautiful and, again with an eye on my credulity meter, 'interesting'. The original study contained two years' worth of numbers; did CNW sit on it for a year because they were waiting for the right time to release the study, or did they wait until they felt they had vetted their numbers, or did they have some other reason?

    Again I feel compelled to say that this does not look to me as anything remotely weighty enough to toss the whole study out as garbage. Or should I say to send the the study into the recyling stream. ;) I find the study, its methods, and its results to be downright fascinating, and I dearly hope they keep publishing figures. I'd love to see how hybrids fare over, say, 10 years, by CNW's D2D method of reckoning. Especially compared to my Fit!
     
  6. Chuck

    Chuck just the messenger

    wdb,

    If you are also bent on insisting the world is flat and the Moon Landings were faked, reasoning is utterly useless. To top it off, you are questioning everyone else's judgement. {sigh}

    You are not going to find a reputable source supporting Dust to Dust, but you will find plently refuting it. Here. Googling it.

    Reasoning is not the issue - it's your denial.

    Saying it's true over and over does not turn myth into reality.
     
    Last edited: Jan 6, 2009
  7. mparrish

    mparrish Rosie the Riveter Redux

  8. mparrish

    mparrish Rosie the Riveter Redux

    And indeed you may be right on the comparison.

    Remember that the denominator is everything. Total D2D energy usage of the Prius was 3x less than the Hummer, even with the controversial heavy weighting of the production portion (see Gleick link above).

    So when a study uses assumptions that are suspect AND are just enough to undo the impact of the numerator, in most people that raises red flags.

    379,000 miles in a Hummer, 109,000 in a Prius. That huge disparity simply doesn't pass the laugh test. You could make a case that the average Hummer might last longer. Maybe 20k. Maybe 70k. Hell, I'll give you double............109k. But 270K? Please.

    But of course they NEED that 270k and the 3.X multiple it provides. Otherwise the Prius "wins". So 270k it is.
     
    Last edited: Jan 7, 2009
  9. lightfoot

    lightfoot Reformed speeder

    Well then there you have it: the study was done to draw attention to CNW. If the results were predictable, the study would not have drawn attention. So they had to reach a surprising conclusion to achieve their goal. That is the bias.

    A scientific study to determine the difference between D2D of hybrids and non-hybrids would have compared the D2D costs of two comparable vehicles. An HCHII and a conventional Civic of the same vintage would have been ideal for this. That is how science is done: you eliminate extraneous variables in order to isolate the effect of a few variables (ideally just one). Not only are the results more meaningful, in this case the study would be much easier to do because it could be a differential study: looking only at the components, production methods, etc that differ between the two otherwise identical vehicles.

    I too would welcome a study of the latter type. Unfortunately, the goal and design of the CNW study do not allow useful and meaningful comparisons to be reached from it.
     
    Last edited: Jan 6, 2009
  10. wdb

    wdb semi-hyper

    CNW's response:

    http://www.cnwmr.com/nss-folder/automotiveenergy/Response to Pacific Institute.pdf

    The mileage numbers for the H1 do seem pretty wild. Does it matter? After all the hubbub under discussion compares the H3 to the Prius. (CNW gave the H3 a 207,000 mile lifespan.) Well, yeah it does, because if that number is wildly wrong (assuming it IS wrong and not just a result of their different -- possibly more in depth? -- methodology) then it calls the rest of their data into question. I have not seen anything from CNW giving justification for the number assigned to the H1, and that is a definite mark against them in my book.

    Possibly, and the existence of that kind of bias would provide one explanation for the timing of the report's publication. But in the beginning of the report itself CNW indicates that D2D is the result of several years of brainstorming, meetings, determinations as to what to include, etcetera, followed by more time spent collecting and collating the data. If the goal was purely just to publicize their company, why not simply throw something together and get it out there?

    They're in there. I'm having a little trouble with formatting the columns; the first column is the study year, second is Civic, third is Civic Hybrid.

    2005 $2.420 $3.238
    2006 $2.361 $3.398
    2007 $2.867 $2.943

    Also, CNW recommends that people use their data to compare vehicles in the same segments. Not exactly the same as comparing hybrid vs. conventional, but certainly a good way to reduce any bias that might be due to assumptions made about categories, such as the heavy development costs applied to the Prius.

    I found one interesting passage in the report, which may speak more to their reason for producing it than anything else I've read so far.
    While interesting from the standpoint of motivation for producing the report, I don't happen to agree with it. I prefer to view tax breaks for hybrid purchases as a means of promoting a technology that has significant long term potential to improve the lives of everyone in the country. (It's also a regressive tax, favoring the wealthier consumer over the less well-off, but that's a different discussion.)
     
  11. donee

    donee Well-Known Member

    Hi All,

    WDB first reply to Delta Flyer proves he does not have the technical background sufficient to conduct a reasonable discusion on this topic. Please do not feed the trolls. Unless you like talking science with a ostrich for your own giggles. Your not going to change his mind, and it don't matter if the earth is round, or the sky is blue , or people landed on the moon. WDB just is not interested in facts....
     
  12. wdb

    wdb semi-hyper

    Sigh. Alrighty then. As DONEE appears to be the voice of reason here, I will respond in kind. DONEE has hit the nail on the head, and obviously has read true meaning hidden behind every word of my responses. I own 4 Hummers and you will pry their keys from my cold, dead fingers!!!!1!!!

    Thanks to those of you who sent me links and who responded thoughtfully. To DONEE and friends, I'd send you a get well card for that sprained knee but I'd rather not incur the environmental costs.

    And with that I take my leave.
     
  13. lamebums

    lamebums Member

    The only glaring problem I see is the number of miles each car is driven. 370k for a Hummer, or any GM vehicle, is ridiculous. I don't know of *anyone* with a GM vehicle that has even half that. The highest I've ever seen in any GM vehicle is 149k, and it was riddled with problems by then.

    Hell, I could put 109k miles on a Prius in three years. I'm sure the Prius would last longer than that.


    I know how the nickel is mined in Canada, shipped to China where the batteries are manufactured, then to Japan where it's put in a car, and then shipped here. And the upfront cost (pollution) may well be more than a Hummer. But the Prius is getting better than 10 MPG over its life.
     
  14. mparrish

    mparrish Rosie the Riveter Redux

    Funny, I actually read this again before you posted it yesterday.

    The most controversial part of the report is the miles driven, of course. Here is CNW:

    Got that?

    It's not that the Prius lasts 109k. It's that by the time I hit 109k, Toyota will:

    (1) announce a new PHEV
    (2) announce they will no longer service my 2007 GenII
    (3) allow me to return my GenII for crushing or abandoning (since nobody will want to buy "obsolete technology") in exchange for a PHEV purchase.

    That makes sense.
     
  15. Earthling

    Earthling Trying to be kind to Mother Earth

    CNW's response is more laughable than their original "study."

    Prius will become obsolete sooner because it is so high-tech? That's absurd.

    It is the FSP hulks that are obsolete, not the Prius. Obsolescence has nothing to do with the amazing engineering in a Prius. As long as there are spare parts available, and replacement batteries, the argument that a Prius will become obsolete sooner because it is high tech in not a legitimate argument concerning the Prius. Rather, it is just one more indictment of CNW and their BS.

    Anyone who gives CNW any shred of credence needs to examine his own thought processes and biases. I guess what I'm saying is only a damned fool would give CNW more than a passing thought, let alone support any of their nonsense.


    Harry
     
  16. Taliesin

    Taliesin Well-Known Member

    Hmm... New figures they should use due to the "obsolete" reasoning?

    Hummer: 2.0 miles
    Prius: 109K miles

    I wonder what that does to the final numbers?

    The technology in the Prius is what makes the technology in the other vehicles unusable (to a certain extent).

    But then again, the auto transmission supposedly made the manual obsolete and look at how many are still out there.

    Either way, it's a very weak argument.
     
  17. Chuck

    Chuck just the messenger

    My commentary on those that agitate - not reason in discussions


    {replying to the Dust to Dust study}

    [​IMG]

    YOU LIE!!!
     
    Last edited: Sep 10, 2009

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