GM Inside News Forum banner
1 - 11 of 11 Posts

·
Registered
Joined
·
15,633 Posts
Discussion Starter · #1 · (Edited)
http://blog.wired.com/cars/2008/05/the-ultimate-pr.html

Go Green -- Buy a Used Car. It's Better Than a Hybrid

By Chuck Squatriglia May 19, 2008 | 7:00:00 PM


Ditching your gas guzzler is a great way to reduce your carbon footprint, but if you really want to do something about global warming, get a used car. You'll be putting less carbon dioxide into the atmosphere.
As Matt Power notes in this month's issue of Wired, hybrids get great gas mileage but it takes 113 million BTUs of energy to make a Toyota Prius.
Because there are about 113,000 BTUs of energy in a gallon of gasoline, the Prius has consumed the equivalent of 1,000 gallons of gasoline before it reaches the showroom. Think of it as a carbon debt -- one you won't pay off until the Prius has turned over 46,000 miles or so.
There's an easy way to avoid that debt -- buy a used car. The debt has already been paid. But not just any used car will do.
It has to be something fuel efficient. Like, say, a 1998 Toyota Tercel that gets 27 mpg city / 35 mpg highway miles. The Prius will have to go 100,000 miles to achieve the same carbon savings as the 10-year-old Tercel. Get behind the wheel of a 1994 Geo Metro XFi, which matches the Prius' 46 mpg, and the Prius would never close the carbon gap, Power writes
We've undoubtedly left some off the list. But the point is, you don't need to buy a Prius -- or any other hybrid, for that matter -- to get great fuel economy and minimize your carbon footprint. You might feel better driving a hybrid, but you won't necessarily be greener.
Oooooh noooooo.........
 

·
Registered
Joined
·
5,887 Posts
Interesting - while the main point of the article is correct (buying a used car is more environmentally friendly than forcing another new one to be built, adding yet another car to the planet), you may want to also include the approximate energy required to produce vehicles other than the Prius. Because after all, without context the 113 million BTU number is completely meaningless. By the way, the site I got this from is one of the sources for the article linked above.

Source: http://www.triplepundit.com/pages/askpablo-time-to-get-a-new-car-002538.php

Using the GREET assumptions I will compare several vehicles, a Hummer H2, a Toyota Prius, and the Toyota Highlander (standard and hybrid). I will use the vehicle's published curb weight to determine the energy used in manufacturing, based on the mmBTU/lb factors above and I will use the average MPG (city and highway) to estimate fuel usage over a 160,000 mile lifespan. The energy required to manufacture the vehicles is:
  • Hummer H2: 200.717 mmBTU
  • Toyota Prius: 113.322 mmBTU
  • Toyota Highlander: 107.133 mmBTU
  • Toyota Highlander Hybrid: 155.18 mmBTU
Gasoline contains 113,500 BTU (0.1134 mmBTU) per gallon. By dividing the expected lifespan of a vehicle (160,000) by its average MPG we can determine the gallons of gasoline used over that lifetime. We can also multiply this by the energy content of the fuel to get the total energy used. The gallons used during a 160,000 mile lifespan and the energy contained therein is:
  • Hummer H2: 13,913 gallons ($44,800 at today's prices!), 1579.13 mmBTU
  • Toyota Prius: 2,883 gallons, 327.207 mmBTU
  • Toyota Highlander: 6,400, 726.4 mmBTU
  • Toyota Highlander Hybrid: 5,424, 615.593 mmBTU
So, in comparison, 89% of the energy consumed by a Hummer H2 is in burning fuel, whereas the Toyota Prius uses 74% of total energy on burning fuel. This means that, in relation to weight, the Prius requires more energy to manufacture, but the Hummer uses far more energy to operate. What we also learn is that a Hummer H2 uses more energy in the first 24,000 miles (roughly 2 years) than the Prius will in its entire lifetime.

Here is my advice, David: Continuing to drive an older car with poor fuel economy is less environmentally friendly than getting a new car that gets drastically better fuel economy. You can take my factors above and calculate the exact energy use for your old vehicle and a new vehicle to see the comparison. Keep in mind that these results are for the energy used, not the carbon dioxide emissions, but the two are highly correlated since most of our energy comes from fossil fuels.
Also, the environmental impact in this discussion so far seems to be focused mainly on energy consumption. At some point, an older car will pollute far more smog-forming emissions (unburned hydrocarbons, etc.) than will a newer car. Don't believe me? Stand behind a 2008 Malibu with the engine running and you'll barely smell anything. Do the same with a 1988 Grand Am and tell me how it smells.
 

·
Registered
Joined
·
15,633 Posts
Discussion Starter · #3 · (Edited)
Interesting - while the main point of the article is correct (buying a used car is more environmentally friendly than forcing another new one to be built, adding yet another car to the planet), you may want to also include the approximate energy required to produce vehicles other than the Prius. Because after all, without context the 113 million BTU number is completely meaningless. By the way, the site I got this from is one of the sources for the article linked above.

Source: http://www.triplepundit.com/pages/askpablo-time-to-get-a-new-car-002538.php


Also, the environmental impact in this discussion so far seems to be focused mainly on energy consumption. At some point, an older car will pollute far more smog-forming emissions (unburned hydrocarbons, etc.) than will a newer car. Don't believe me? Stand behind a 2008 Malibu with the engine running and you'll barely smell anything. Do the same with a 1988 Grand Am and tell me how it smells.
Hmmmm , where are the transportation energy costs to bring the Prius here ???

Thats more important than most realize as we now know that measured green house and pollution effects from heavy seaborne transport were previously understated by a factor of 5-7.

Again, since the used vehicle is already here its factor is zero - regardless of origination.

Also, the energy costs here for the Prius ( I think - not sure - check later ), - do not include the carbon/energy foot print for its rather unique pre assembly 'transport' requirements.

Where are the energy costs for either one - for recycling ???

Actually the 'energy costs' of other new vehicles are completely irrelevant - its used cars versus the Prius.

And as to pollution costs or footprints the article is limited to a carbon footprint comparison .

Having said that, yes I agree total environmental impact is an important part of the overall equation - one which only buttresses the argument made here against the Prius as the only green solution and calls into question if the Prius is 'really ' 'green' at all.

If you try and account for the total environmental impact of a Prius from cradle to grave no matter how you do it, its not even mid pack - amongst new and, obviously, is an even bigger loser against used.

As to standing behind a vehicle to sample the pipe and draw a conclusion.............. well, there are better ways to do that.

Other tailpipe emissions have to be measured very specifically to draw comparison values.

Since we're comparing used cars ...... and all kinds of drive cycles for both new and used.................. well good luck.

Also worth noting, its common now when comparing different emissions numbers to skew the argument to the point of absurdity by ignoring the total, operational count and over focus on next to useless rate remaining theoretical comparisons.

As the UK is finding out, you also need for obvious reasons real world FE numbers.

Its somewhat of an exercise in futility anyway.

Based on the molecule/compound 'type' count, most are not measured anyway.

Finally Argonne Lab's GREET model has been very controversial - no surprise, it appears somewhat biased against some and biased for others - like battery hybrid PT systems.

A revised version was recently released.
 
Joined
·
5,934 Posts
My head hurts ....
 

·
Registered
Joined
·
5,887 Posts
Hmmmm , where are the transportation energy costs to bring the Prius here ???

Thats more important than most realize as we now know that measured green house and pollution effects from heavy seaborne transport were previously understated by a factor of 5-7.

Again, since the used vehicle is already here its factor is zero - regardless of origination.

Also, the energy costs here for the Prius ( I think - not sure - check later ), - do not include the carbon/energy foot print for its rather unique pre assembly 'transport' requirements.

Where are the energy costs for either one - for recycling ???

Actually the 'energy costs' of other new vehicles are completely irrelevant - its used cars versus the Prius.

And as to pollution costs or footprints the article is limited to a carbon footprint comparison .

Having said that, yes I agree total environmental impact is an important part of the overall equation - one which only buttresses the argument made here against the Prius as the only green solution and calls into question if the Prius is 'really ' 'green' at all.

If you try and account for the total environmental impact of a Prius from cradle to grave no matter how you do it, its not even mid pack - amongst new and, obviously, is an even bigger loser against used.

As to standing behind a vehicle to sample the pipe and draw a conclusion.............. well, there are better ways to do that.

Other tailpipe emissions have to be measured very specifically to draw comparison values.

Since we're comparing used cars ...... and all kinds of drive cycles for both new and used.................. well good luck.

Also worth noting, its common now when comparing different emissions numbers to skew the argument to the point of absurdity by ignoring the total, operational count and over focus on next to useless rate remaining theoretical comparisons.

As the UK is finding out, you also need for obvious reasons real world FE numbers.

Its somewhat of an exercise in futility anyway.

Based on the molecule/compound 'type' count, most are not measured anyway.

Finally Argonne Lab's GREET model has been very controversial - no surprise, it appears somewhat biased against some and biased for others - like battery hybrid PT systems.

A revised version was recently released.
The very first thing I said was that the overall conclusion in the original article was correct - buying a used car is not only more fiscally responsible but also keeps one more new car off the roads. If there are 200 million cars in the US (whatever the number is), at least there's not 200,000,001 if one person decides to buy used instead.

With regard to the transportation, etc. costs - you're correct. I have no idea what the energy consumption is for a trans-oceanic container ship, but they are HUGE and carry a lot of cargo/vehicles. Similar to the way a city bus uses a lot more fuel than an Aveo, but in terms of fuel burned per pound of cargo (or per passenger) the bus is more efficient. Or, a Suburban carrying 8 passengers getting 15 mpg is more efficient than a Camry carrying four at 25 mpg.

But the point is, the 113 million BTUs figure for the Prius is worthless without context. Since you cited that number, I provided context for that number. You didn't question the validity of the 113 million BTU number in your first post, but now that it's stacked up against other vehicles, you can see it's not really all that bad. Everything is relative (but again, a used car requires 0 million BTUs to produce, since it's already been produced). If you are prepared to throw out the GREET study, then you should also be prepared to throw out the 113 million BTU figure for the Prius, then throw out any and all calculations in this thread pertaining to the Prius' energy cost and/or environmental impact. Becuase without that one hard number (which itself is just an estimate based on the car's weight and its typical component materials), there is no factual basis for demonstrating the Prius' energy consumption during manufacturing and demanufacturing.

WRT the tailpipe emissions, are you disputing that every new 2008 model year midsize sedan is cleaner than a comparable 20 year old model, either looking at the 1988 model today or when it was new?

Finally, the cradle-to-grave argument about the Prius has been beaten to death. The CNW Marketing Research study was rocked with completely flawed assumptions. The article linked in your first post led to an excellent rebuttal of that study based on more reasonable assumptions. For someone so concerned about the underlying assumptions in any given study, I'd expect you to pay more attention to those.;)
 

·
Registered
Joined
·
15,633 Posts
Discussion Starter · #6 · (Edited)
The very first thing I said was that the overall conclusion in the original article was correct
. YEP.

Sometimes its just better to quit while you're ahead - and on topic..

With regard to the transportation, etc. costs - you're correct. I have no idea what the energy consumption is for a trans-oceanic container ship, but they are HUGE and carry a lot of cargo/vehicles. Similar to the way a city bus uses a lot more fuel than an Aveo, but in terms of fuel burned per pound of cargo (or per passenger) the bus is more efficient. Or, a Suburban carrying 8 passengers getting 15 mpg is more efficient than a Camry carrying four at 25 mpg.
Well, isn't that confusing - the relevant comparison would be a used car with no "trans - oceanic" carbon footprint versus a Prius with one that really matters.

Shipping efficiencies however alluded to are completely irrelevant in this comparison when the used vehicle has no SHIPPING involved.

But the point is, the 113 million BTUs figure for the Prius is worthless without context.
OK, RELEVANT context it is.

- used anything from anywhere = 00.000 - thats the useful, relevant context here.

Since you cited that number, I provided context for that number.
NOPE.
You provided nothing useful here but confusion - this would be possibly useful if we were comparing a new vehicle to the Prius. Really tho, in light of the context here, it looks like a Prius-is green-salvage-operation wrapped in a shift-the-topic-post.
You didn't question the validity of the 113 million BTU number in your first post, but now that it's stacked up against other vehicles, you can see it's not really all that bad.
NOPE.
what I can see and alluded to is that it is so flawed by way of incompletion as to be worse than useless - or really ONLY useful for misleading the public about the Prius - when comparing new vehicles. So there is no further confusion, I'll draw you the rest of the picture. Since the used vehicles listed have a markedly lower carbon number anyway, the 13 million while incomplete and low can still be used ( crudely ) when comparing a new Prius to a used vehicle - just as this author did.
Everything is relative (but again, a used car requires 0 million BTUs to produce, since it's already been produced). If you are prepared to throw out the GREET study, then you should also be prepared to throw out the 113 million BTU figure for the Prius, then throw out any and all calculations in this thread pertaining to the Prius' energy cost and/or environmental impact. Becuase without that one hard number (which itself is just an estimate based on the car's weight and its typical component materials), there is no factual basis for demonstrating the Prius' energy consumption during manufacturing and demanufacturing.
Look, if all you can do is uselessly confuse topics and responses by adding and mixing them together while ignoring whats really being written then we can stop here.

Where we agree - I think.

That would be that as far as a carbon footprint based automotive purchase decision goes, there are many other used vehicle choices to consider as green as if not more so than a new Prius - which is what the author basically wrote.

WRT the tailpipe emissions, are you disputing that every new 2008 model year midsize sedan is cleaner than a comparable 20 year old model, either looking at the 1988 model today or when it was new?
No.
Responding to your post as written - the most important aspect of that complicated question is by how much - in the real world - and what then is the value of that in the bigger equation as well as what are the environmental and other costs of that cleaner pipe.

Finally, the cradle-to-grave argument about the Prius has been beaten to death.
Your opinion only. Mine is that an updated, honest and open appraisal needs to be done and discussed.
The CNW Marketing Research study was rocked with completely flawed assumptions. The article linked in your first post led to an excellent rebuttal of that study based on more reasonable assumptions. For someone so concerned about the underlying assumptions in any given study, I'd expect you to pay more attention to those.;)
Thats an inaccurate summation of the CNW study in the extreme.

Its the misuse of it - by partisans on both sides of many issues that is the problem.

None of the rebuttals I've read are worth a damn either , but rather seem to be strictly agenda driven only.

CONSPICUOUS IN ITS ABSENCE IS A OPEN, DETAILED 'ENVIRONMENTAL' 'ACCOUNTING' FROM TOYOTA - AS REBUTTAL.

Given how Toyota will talk up its accomplishments both real and imagined this is more than a bit surprising.
 

·
Registered
Joined
·
5,887 Posts
Blah blah, Toyota sucks, blah blah. I know something's going on with you when you break out the larger font to make your point.

This thread is on the fast track to the snake pit.

Like GM, Toyota is in the business of selling new cars. Their corporations make no money when used cars are sold (unless they get some sort of markup from CPO sales). As I am now saying in the third post in a row, that basic contention that buying a used fuel efficient car has a smaller environmental impact is correct.

The point of what I'm saying is that if you do want to buy a new car (personally, I don't plan on buying a 12 year old Geo Metro, or old Toyota Tercel (ick) even if they have far smaller carbon footprints than the cars I like), and are prepared to take the depreciation hit, there are cars far worse than the Prius from an environmental impact standpoint. A Yaris is probably much better, but a Hummer H2 is probably much worse. There really is no reason to single out the Prius other than the fact that many people - thanks in large part to Toyota's success in marketing the car - think the car is extremely low-impact on the environment when in fact, other than great fuel economy/CO2 emissions/smog-forming emissions (which it does do well), it's probably about average in terms of environmental impact. I'm sure you will argue all day that it's far worse than average, but I really don't care.

Your point, and I understand it, is that Toyota wraps themselves in a holier-than-thou persona when it comes to selling "environmentally responsible" products, when in fact they probably aren't any better than what anyone else offers. You're right...especially after spending the past few days driving a Sequoia to review and getting ~ 13 mpg.
 

·
Registered
Joined
·
4,022 Posts
Also, the environmental impact in this discussion so far seems to be focused mainly on energy consumption. At some point, an older car will pollute far more smog-forming emissions (unburned hydrocarbons, etc.) than will a newer car. Don't believe me? Stand behind a 2008 Malibu with the engine running and you'll barely smell anything. Do the same with a 1988 Grand Am and tell me how it smells.
Smog is good, at least from a “global warming will kill us all” prospective.
 
1 - 11 of 11 Posts
Top