What kind of car(s) do you guys drive?

[_xxx_]

Well, of course. But I do somewhat wonder at the emission/gal differences between Diesel and Gasoline.

The modern diesel engines with particle filters have very low emissions, only NOx are still a bit higher than with gasoline engines and of course, gasoline produces no particles.

Here's a table FYI, current norm is EU4:
http://www.kfztech.de/kfztechnik/motor/abgas/abgaswerte.htm

EDIT:
WhiningKhan beat me to it, haven't refreshed...

 

[KimB]

Well, the emissions in those graphs have more to do with the efficiency of the combustion.

I'm more wondering about CO2. I think it'd be interesting to see an analysis of CO2 emission per gallon for Gasoline vs. Diesel (it'd be especially nice if it were quoted as total production from digging it out of the ground to the time it's used as fuel in a vehicle).

 

[_xxx_]

Well, the emissions in those graphs have more to do with the efficiency of the combustion.

I'm more wondering about CO2. I think it'd be interesting to see an analysis of CO2 emission per gallon for Gasoline vs. Diesel (it'd be especially nice if it were quoted as total production from digging it out of the ground to the time it's used as fuel in a vehicle).

These are related to mileage, but if you scroll down, there's a link to the PDF where a bunch of cars' values are collected. Count in the consumption and you can calculate yourself

http://www.kfztech.de/Unterricht/downloads/Emiss_2005_int.pdf

The legal requirements are always related to emissions/km (or mile), not to consumption. Doesn't matter if it's 0.01 mpg or 1000 mpg, as long as they don't emitt more than prescribed.

 

[WhiningKhan]

These are related to mileage, but if you scroll down, there's a link to the PDF where a bunch of cars' values are collected. Count in the consumption and you can calculate yourself

http://www.kfztech.de/Unterricht/downloads/Emiss_2005_int.pdf

The legal requirements are always related to emissions/km (or mile), not to consumption. Doesn't matter if it's 0.01 mpg or 1000 mpg, as long as they don't emitt more than prescribed.

Errr... No need to even calculate, they give CO2 g/km directly.

Chalnoth, it's quite obvious that higher-MPG diesel produces less CO2 than lower-MPG gasoline - the more fuel you consume, the more exhaust it produces. The carbon content in diesel fuel and gasoline is not that different.

EDIT: Ah, he asked for CO2 per gallon (irrelevant as it is, though). Sorry, ignore me.

 

[_xxx_]

Errr... No need to even calculate, they give CO2 g/km directly.

Yes, but he asked about g/gallon consumed, not g/km and that has nothing to do with mileage

EDIT: oops, I'm blind as well, it seems...

 

[KimB]

http://www.kfztech.de/Unterricht/downloads/Emiss_2005_int.pdf

Not reading German it's rather hard for me to make heads or tails of this.

The legal requirements are always related to emissions/km (or mile), not to consumption.

Which makes sense, but isn't directly related to what I'm wondering. After all, in principle, Gasoline and Diesel could have quite different ratios of carbon to hydrogen (I don't know the chemical structures), and the one with more hydrogen per carbon would probably both burn hotter and produce less CO2 per amount of energy released.

 

[ShootMyMonkey]

Only particulate and NOx emissions are worse on diesel. In practice, NOx difference is not significant, and current particle traps all but eliminate the other problem. Also, the quality of diesel fuel can be improved.

Some people argue what biodiesel does for NOx levels. But for the most part, I think overall difference is near zero. I think any real difference that shows up is attributable to mileage differences due to the fuel. The real benefits are with the sulfur levels and particulate emissions.

As far as NOx is concerned, most automakers lean towards urea injection to deal with NOx. Though it involves an extra cat, it does work. The core problem that the EPA has with it is that you've basically added a second fluid that needs regular refills in line with fuel, and they think the public is too complacent and stupid to keep track of more than one fluid level (which by in large is probably true).

 

[poopypoo]

When it goes where I want, I take the metro!

when it doesn't, i have the trusty BUS and BIKE. big citiez pwn!!!

 

[KimB]

when it doesn't, i have the trusty BUS and BIKE. big citiez pwn!!!

Unfortunately, not all big cities in the US have good public transportation.

 

[WhiningKhan]

Not reading German it's rather hard for me to make heads or tails of this.

Come ON, you're just playing ignorant now. You must know what CO2/km and l/100km are in English? And while I'm not german, even I can tell you that 'innerstädt' means driving in city and 'ausserstädt' means driving outside the city. I wonder if you can guess what 'insgesamt' means...? Googling and online translators do work, too.

Which makes sense, but isn't directly related to what I'm wondering. After all, in principle, Gasoline and Diesel could have quite different ratios of carbon to hydrogen (I don't know the chemical structures), and the one with more hydrogen per carbon would probably both burn hotter and produce less CO2 per amount of energy released.

While both are mixtures of varied hydrocarbons and no unambiguous definition exists, the elementary ingredients describing gasoline and diesel are both alkanes (iso-octane and cetane, respectively). As such, the carbon content is similar, as I wrote in earlier post.

 

[KimB]

Come ON, you're just playing ignorant now. You must know what CO2/km and l/100km are in English? And while I'm not german, even I can tell you that 'innerstädt' means driving in city and 'ausserstädt' means driving outside the city. I wonder if you can guess what 'insgesamt' means...?

And I would not have guessed those two words at all. Anyway, all I'm saying is, don't throw a huge PDF file and expect me to pore through it to find those bits and pieces which I can understand.

 

[WhiningKhan]

And I would not have guessed those two words at all. Anyway, all I'm saying is, don't throw a huge PDF file and expect me to pore through it to find those bits and pieces which I can understand.

I didn't, but those of us who are from non-English speaking country have been doing what you just refused to do for all of our lives...

 

[KimB]

I didn't, but those of us who are from non-English speaking country have been doing what you just refused to do for all of our lives...

Well, I don't mind doing it for languages that I've learned a little bit of (French, Japanese), but dude, that's a 728-page PDF. Even if it were all in English I doubt I could find the motivation to find relevant information.

 

[WhiningKhan]

Well, I don't mind doing it for languages that I've learned a little bit of (French, Japanese), but dude, that's a 728-page PDF. Even if it were all in English I doubt I could find the motivation to find relevant information.

Of which, 700 pages are made up of only 7 tables, and word "CO2-emissions" pops out in the subject of table 1 within a couple of seconds as you start scrolling. I hate it when people don't seem to have the will to try nowadays (especially in engineering students I see it as a sign of looming disaster) But okay, no more whining from me.

EDIT: Oh, and I currently drive a diesel, if someone didn't guess already, although I don't really do it for environmental or fuel-economical reasons. I just drive it.

 

[CitrousRapture]

here it is. I re-learn everyday why most cars are not turbocharged. she gets a lot of looks though =)

http://www.cardomain.com/ride/647892

 

[_xxx_]

Chal, you must be a real couch potato!

Just choose one gasoline and one diesel car you 're familiar with from that table and look at the values, that's like 5 minutes of work. You're the one interested in the values, you don't expect that we calculate it for you, huh?

 

[KimB]

Just choose one gasoline and one diesel car you 're familiar with from that table and look at the values, that's like 5 minutes of work. You're the one interested in the values, you don't expect that we calculate it for you, huh?

It was a bit more than that, but come on, this is a webforum, not a job...

Regardless, I checked it out, and from what I can tell, it looks like by volume, Diesel produces about 10-15% more CO2 than Gasoline. Of course, the improvement in mileage overshadows this.

 

[WhiningKhan]

Regardless, I checked it out, and from what I can tell, it looks like by volume, Diesel produces about 10-15% more CO2 than Gasoline. Of course, the improvement in mileage overshadows this.

By volume, yes, but not by mass... As diesel consists of longer hydrocarbons, it is more dense, which makes the comparison meaningless.

 

[_xxx_]

By volume, yes, but not by mass... As diesel consists of longer hydrocarbons, it is more dense, which makes the comparison meaningless.

Don't you be so nitpicky!

 

[Sage]

here it is. I re-learn everyday why most cars are not turbocharged. she gets a lot of looks though =)

http://www.cardomain.com/ride/647892

nice... yeah, i bet she does get alot of looks in that bikini!!!