Pet peeve: "clean diesel" greenwashing

[gone-ot]

...to put some perspective on it: Just how "green" can a power-plant be that requires "piss" (urea) to be dumped into its exhaust system?

...almost makes the 'old' diesel smell "sweet" by comparison, don't it?

[Ryland]

The term Zero Tail Pipe Emissions is an accurate statement because our EV's do not have tail pipes.
The same way "clean" is a relative term, after I wash my dishes they are "clean" but if I washed them a 2nd time they would be "cleaner" right? every time I wash them they will get cleaner and cleaner.

[gone-ot]

a virgin virgin, or a virgin·er virgin?

[Piwoslaw]

Originally Posted by MetroMPG

We know is not true. In 20 years the current crop of engines will probably be considered gross polluters.

You don't have to wait 20 years for them to be dirtier - every engine becomes less clean as it ages. European emissions standards take this into account and now have different limits for when the brand-new car leaves the factory and when it is being exploited on the road.
I totally agree with MetroMPG that no diesel (or any other fuel) powered vehicle is technically clean until its tailpipes emissions are exactly the same as intake air, molecule for molecule. When buying a "clean" car we only trying to pick the lesser evil.

Originally Posted by UFO

The new crop of diesels with DPFs have cleaner emissions, that's a fact. Unfortunately, they are still filthy in terms of the amount of petroleum they are designed to burn. The cursed VW TDI is warranted to use ONLY 5% biodiesel -- I will never buy one unless I can convert it to burn 100% biodiesel like any good diesel should.

New diesels with DPFs increase fuel consumption and aren't too reliable, as Euromodder can testify. They also require cesium and/or urea based fluids to work properly.
PSA (Citroën/Peugeot) says its HDi turbodiesels can take up to 30% biodiesel, but it has to be premixed - you can't just pour 7 gallons of regular diesel, followed by 3 gallons of 100% bio, into your tank. Plus normal fuels here in the EU (not sure about the US) already have 5% biocomponents in them, more to satisfy the farming lobby than for cleaner emissions.

[user removed]

Untruth in advertising is almost as old as the oldest professsion known to mankind.

Think snake oil and permanent waves.

regards
mech

[hamsterpower]

I thought "Clean Diesel" refered to before you burn it. Looking a diesel today it is almost clear, where years ago i thought it was more like used motor oil.

[Diesel_Dave]

Originally Posted by Old Tele man

...to put some perspective on it: Just how "green" can a power-plant be that requires "piss" (urea) to be dumped into its exhaust system?

...almost makes the 'old' diesel smell "sweet" by comparison, don't it?

The urea used in SCR systems turns into N2, CO2, & H20 before it goes out the tailpipe. Occasionally some ammonia slips out, but that's typically limited to less than 5 ppm or so. The primary reason it's not allowed above that is just so nearby people don't smell the ammonia.

[Diesel_Dave]

Originally Posted by Piwoslaw

New diesels with DPFs increase fuel consumption and aren't too reliable, as Euromodder can testify. They also require cesium and/or urea based fluids to work properly.
PSA (Citroën/Peugeot) says its HDi turbodiesels can take up to 30% biodiesel, but it has to be premixed - you can't just pour 7 gallons of regular diesel, followed by 3 gallons of 100% bio, into your tank. Plus normal fuels here in the EU (not sure about the US) already have 5% biocomponents in them, more to satisfy the farming lobby than for cleaner emissions.

I'll agree with the increased fuel consumption and decreased reliability of DPF systems, however, urea is used for SCR--not DPF. Some vehicles (including mine) were manufactured with a DPF, but not a SCR. The DPF is for particulates while the SCR is for NOx. My truck was made with a lean NOx trap (adsorber) rather than an SCR system.

[JasonG]

Acording to Euro standards, they are less polluting than gassers.
Looks like Cali is reinvestigating diesel exhaust.
Gasoline worse than diesel when it comes to some types of air pollution
Some plusses and minuses of both.

Still, nothing is "clean" just cleaner.

[mechman600]

A few years ago I heard talk of DPFs for gasoline engines as well. While gas engines may not have visible particulates like unfiltered diesels, the tiny particulates they do produce are equally as nasty, if not worse.