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I was wondering when, if ever, the new low sulfur diesel comes out it will be at all comparable with gas? Is there a web site that discusses this anywhere? A hybrid diesel could be pretty good, but I don't have a good understanding how good this new diesel will be as far as being more environmentally friendly.

Anyone know much about this or have a web site link?

Thanks,
Curt
 

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You don't have to wonder. Just look for EPA rating labels, like SULEV & PZEV.

The cleaner diesel does make those levels of clean realistic, but whether or not an automaker will actually deliver vehicles that achieve them is an entirely different matter.

Regardless, an engine-only automatic diesel still cannot compete with a "full" hybrid in mixed driving conditions when it comes to efficiency. The real-world data clearly confirms that.
 

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There's also the problem of particulate emission to be taken into account. Particulates are one of the problems in diesel engines (remember the black smoke coming from tailpipes?). Modern diesel engines are much better but there's one snag: Emissions are measured in mass (i.e. µg of particles/m3 of air). New engines emit a higher number of particles, but with a much smaller diameter. As mass decreases with the 3rd power of diameter, you can reduce the mass even when the number increases. The big question now is: what causes health problems? Is it the particle mass, the surface or the number???? This is still much debated in the scientific community.
I guess what should really drive this discussion is not just the fuel efficiency, but the emissions. And not just the gaseous emissions (NOx, CO, etc.) but also particulates. I guess the Prius is doing better here than most diesels.
 

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john1701a said:
mgaelli said:
And not just the gaseous emissions (NOx, CO, etc.) but also particulates.
PM (particulate matter) is part of the SULEV & PZEV emission ratings.
But as I mentioed earlier, PM is mass based, so it can still be an issue.
 
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