given the debate that "diesels are dirty", I decided to take a look at the actual numbers for a Lupo 3L/80MPG car:



NOx= TLEV-qualified (0.23 g/km)
HC = ULEV-qualified (0.03 g/km)
CO = SULEV/PZEV-qualified (0.36 g/km)



This is why so many manufacturers say, "After ultra-low sulfur diesel is sold, all we need to do is add better filters to eliminate the NOx." The diesels pass every other measurement except that one, but they can't fix the NOx problem while high sulfur diesel is still in the pumps.

In the other categories, diesel is already a winner:
HC = ULEV-qualified
CO = SULEV/PZEV-qualified

troy

What I do know about diesels is the fuel will finally be cleaned up in 2006. It's likely that the dirty sulfur that was used for lubrication will be replaced by a bio-diesel. It's an improvement...

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

California already has the low sulfur diesel of Europe, and VW cars cannot meet CARB minimum requirements using it.

Talk is of using a urea trap for some of the emissions. I can't help it -- made me wonder if when using biodiesel, the emissions instead of smelling like french fries, will smell like the potty at McDonalds.

R2-E2, 2G Prius.
Highway/City/Husband/Wife MPG: 56.5, as of 12/2005, 26K miles

Jac Nasser, Ford President: "We are planning to launch a hybrid version of
this car [P2000] within this year [1998]. We will also make FCEV available in
2004."

Reminds me of this article.

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

Take a 1980 car. Fill it with low-sulfur California gasoline. Does it suddenly become clean? NOPE. Because the 1980 car doesn't have a catalytic converter, so it's still dirty.

Same with diesels. Low-sulfur is not enough. You need low-sulfur *and* a NOx catalyst. Today's diesels don't have the NOx catalyst.



Once they do, then they can be sold in California as ULEV or SULEV cars.

troy

My beef with diesels are smog and age.
Year after year it's the same old claim of clean diesel cars.
I'm not saying there isn't improvements as they have made great strides.

But 95% of the time when I see an older diesel it either smokes or doesn't smoke but is blowing that unique toxic gas that stings your nose and burns your eyes and throat shut.

Yes these cars were clean by the standard of thier day but now their older- I've noticed usually after 7 years the deterioration begins.
Yes there are older diesels that are fine but these are the exception not the rule.
Yes older gasoline cars can also smoke but the toxic gas described above is absent.
Yes diesel drivers love their car and that's fine- but I avoid like the plague not to be behind one. If I'm stuck in that situation I double my traffic buffer to let the gas blow off to the side.

It will be 14-20 years before I ever consider buying one. In my case it will take that long for the usual yearly claims to prove as reality.

If you look at EPA fueleconomy.gov for 2002 vs. 2005 Beetle TDIs, you'll notice the "smog index" has improved from a 1 (bad) to 6 (average). Difference? New injectors for cleaner-burning. So YES diesels are improving... the claims are not empty.

After NOx filters are added in 2007, that number will probably jump to a 9 (above-average).



I suspect you've driven behind diesel cars, and not even realized it. That often happens to me, until I suddenly notice the "TDI" plaque. You can't tell the difference... there's no smoke or smell.

Also, gasoline cars can be pretty smelly. I was behind a gasser the other day that was blowing a bluish-purple smoke that smelled like a *skunk*. Ewwww!



And as for aging, gasoline cars age *faster*. Lifespan of a gasoline car is 250-300,000 miles typical. Lifespan of a diesel is 500-600,000 miles. Diesels are simpler (example: no ignition system), so there's less to go wrong. Diesels are built with stronger, thicker metals.

Gasoline cars age faster.

troy

I mentioned that diesel cars are getting cleaner out of the box but what after about 7 years?

I'd rather be behind a gasoline engine with a little smoke rather than a diesel anyday. The experience is vastly different.

Troy,

I looked at the EPA database again. The cleanest diesel is the VW bug, which scores a TWO. All the others are ONE.

I am aware that post-combustion devices have low sulfur requirements. And we can talk about what *may* be available in the future. But the fact today is that CA has had low sulfur diesel for years, and the diesel manufacturers best effort is a smog nightmare banned from the road. That is saying something, in the land where the governator has a stable of hummers.

R2-E2, 2G Prius.
Highway/City/Husband/Wife MPG: 56.5, as of 12/2005, 26K miles

Jac Nasser, Ford President: "We are planning to launch a hybrid version of
this car [P2000] within this year [1998]. We will also make FCEV available in
2004."

Diesels are also very high in particulates. Biodiesel reduces the particulate level, but compared to good gasoline cars it is still very high. There are a lot of small particulates that make it all the way to the lung's alveoli (tiny air sacs that do the real work of exchanging gases between blood and air). So the health effectrs of diesels sold in the US is bad. With low sulfur diesel, this can be improved considerably. Does anybody know what level particulates can be reduced to with catalytic converters, etc., with low sulfur diesel? This spring in Germany the air quality was lousy, but it may have been because of old, really dirty diesel buses.
--Walter