The Dirty Truth About 'Clean Diesel' (nytimes.com)

HughPickens.com writes: Volkswagen persuaded consumers it had created a new generation of so-called clean diesel cars — until investigators discovered that phony testing concealed that its vehicles emitted up to 40 times the permitted levels of pollutants during regular use. Now Taras Grescoe writes in the NY Times public outrage over the fraud obscures the much larger issue: "clean diesel" is causing a precipitous decline in air quality for millions of city-dwellers. Monitoring sites in European cities like London, Stuttgart, Munich, Paris, Milan and Rome have reported high levels of the nitrogen oxides and particulate matter, or soot, that help to create menacing smogs. Although automakers worked hard to convince consumers that a new generation of "clean diesel" cars were far less polluting, diesel has a fatal flaw. It tends to burn dirty, particularly at low speeds and temperatures. In cities, where so much driving is stop and start, incomplete diesel combustion produces pollution that is devastating for human health.

Fortunately, Volkswagen sold only half a million of its "clean diesel" cars to the American public before the emissions scandal broke. Today, fewer than 1 percent of the passenger vehicles sold in the U.S. run on diesel fuel. Europe is now scrambling to undo the damage. In London, Mayor Boris Johnson last year called for a national program to pay some drivers to scrap their diesel vehicles. In Paris, Mayor Anne Hidalgo has gained broad support for a proposed ban on diesel cars. "Last month, the signatories of the climate deal in Paris agreed that the world has to begin a long-term shift from fossil fuels to more sustainable forms of energy," concludes Grescoe. "Recognizing "clean diesel" for the oxymoron it is would be a good place to start."

Comments

The brief puff of black soot...

[Viol8]

... that comes out of the back of even new diesel vehicles on hard acceleration tells you all you need to know about how clean diesel really is. Yes, it emits less CO2 per mile than petrol/gasoline for the equivalent power output but thats where its enviromental credentials end.

Re:The brief puff of black soot...

[fatboy]

Isn't that the crux of the problem? We have spent the past 40 years tweaking car technology to convert noxious tailpipe gases to clean, non-toxic CO2. Now that isn't good enough. Time to choose our poison.

Re:The brief puff of black soot...

[Algan]

Funny, I've never seen ANY kind of visible smoke coming out of my new diesel sedan, even under hard revving. Not a VW though. Modern diesels come with filters that capture soot particles and urea exhaust treatment systems to neutralize NOx emissions. Barring cheating, a well built modern diesel vehicle is as clean as its gasoline counterpart.

Re:The brief puff of black soot...

[hey!]

Well, in addition to choices of poison you have to weight your alternative options for paying the piper. You can pay the piper now by tuning your diesel engine to produce either (a) soot or (b) NOx and then add the appropriate emissions equipment, or you can pay it later in terms of adapting to climate changes.

Re:the diesel car has always confounded me.

[SydShamino]

A full urea tank on our BMX X5d lasts at least 3-4 years (we've had to have it refilled once), so it's no where near "30 days". The idiot light is pretty good, too; the car warns you for 1000 miles (counting down) that it won't start when the tank is empty. Now that might not work for a long-haul trucker, but is acceptable for a family SUV.