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Transportation Earth

The Dirty Truth About 'Clean Diesel' ( 496 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."

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The Dirty Truth About 'Clean Diesel'

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  • My nose (Score:3, Insightful)

    by Anonymous Coward on Monday January 04, 2016 @11:27AM (#51234647)

    My own nose is able to tell that diesel isn't particularly clean burning.

  • by Viol8 ( 599362 ) on Monday January 04, 2016 @11:30AM (#51234665) Homepage

    ... 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.

    • by fatboy ( 6851 ) on Monday January 04, 2016 @11:47AM (#51234797)

      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: (Score:3, Interesting)

        by hey! ( 33014 )

        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.

    • My '08 GTI had a black tailpipe from the day I bought it. Turbocharged direct injection engines also suffer from momentary overboost conditions on hard acceleration and they produce soot. What's worse is that many, if not all, of these gasoline engines do not have particulate filters on the exhaust.

      I'll bet if we start scrutinizing the exhaust pipes of all these turbocharged, direct injected gasoline engines, you will find their emissions probably aren't compliant either.

    • by Algan ( 20532 ) on Monday January 04, 2016 @11:49AM (#51234815)

      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.

      • by Viol8 ( 599362 ) on Monday January 04, 2016 @12:16PM (#51235025) Homepage

        "Funny, I've never seen ANY kind of visible smoke coming out of my new diesel sedan, even under hard revving"

        Thats because you're at the front driving it.

      • It's about size (Score:5, Insightful)

        by feranick ( 858651 ) on Monday January 04, 2016 @01:55PM (#51235987)
        Your comments highlight the crux of the problem. Back in the day, inefficient (read truck like) diesel were shooting out black smoke. That particulate is large in size (10 or 100 of microns) that you actually "see". Improvements in efficiencies (both in combustion and trapping) made modern "clean engines" reduced the size of particulate to few microns. Those are much more difficult to see. Yet they are far more dangerous. Large particulate is trapped in your upper respiratory tract, the fine stuff gets deep in your lungs, often bioaccumulaating like abspestos does. You know how the stoey goes. Not because you don't see it it means it's not there... Next time stick a paper towel on the exhaust of your cold diesel and leave it there for a few minutes. Look at the color. Now you have somerhing to "see".
    • ...except that doesn't happen with many diesel vehicles, our BMW X5d included.

  • Diesel Hybrids (Score:4, Insightful)

    by Anonymous Coward on Monday January 04, 2016 @11:33AM (#51234679)

    If diesels pollute mostly at low speeds and temperatures, why not make diesel hybrids, which would allow the diesel to run at peak efficiency and/or cleanliness?

    • Re:Diesel Hybrids (Score:5, Insightful)

      by mrchaotica ( 681592 ) * on Monday January 04, 2016 @11:43AM (#51234759)

      Diesel engines are more expensive than gasoline engines (because they have to be built stronger, and have a turbocharger). Hybrids are also more expensive than gasoline engines (because they have an extra battery and electric motor, or at least an oversized alternator, depending on design). Diesel hybrids would be more expensive twice.

      That said, I'd love to have one.

      • by haruchai ( 17472 )

        Better off with a gas-electric hybrid. Electric motor has even more low-end torque than diesel.

        • by sjbe ( 173966 ) on Monday January 04, 2016 @01:17PM (#51235601)

          Better off with a gas-electric hybrid. Electric motor has even more low-end torque than diesel.

          Depends on the application. Diesels-electrics are used in locomotives and I think they would probably work fairly well in similar applications like in large cargo hauling trucks. I think it wouldn't make sense for a small city runabout or a family sedan but for big trucks I'm kind of surprised we haven't seen it worked on already. Diesels are actually best in steady state applications which is why they are great for trucks. Yes they are torquey but their fuel efficiency is their primary draw and that comes from operating at (relatively) constant speeds.

      • by Ichijo ( 607641 )

        Would a diesel hybrid need a turbocharger?

    • One of the big advantages diesels have over gasoline engines is that they don't have a throttle plate restricting airflow at sub-optimal speeds. When used in a generator, both the gasoline and diesel engines would be run at their peak efficiency and so this throttle restriction would disappear. Now you are left with only the compression advantage of diesel. That advantage gets reduced by the higher complexity, cost, and weight of the diesel engine.

      In short, it's probably not worth the 5% or so increase in e

  • by Anonymous Coward on Monday January 04, 2016 @11:36AM (#51234701)

    This makes a great story:

    40 times the permitted levels of pollutants

    But nobody ever mentions the actual level - which is pretty damn important because 40 times 1 part per thousand is a lot more significant than 40 times 1 part per trillion.

    Yes VW cheated - but lets not forget that the "Clean Diesel" TDIs are MUCH cleaner than the previous generation diesel cars (TDIs included) that were on the market. Anyone who has owned both can tell you, the clean diesel TDIs don't smell, never emit black smoke and the tail pipe stays clean and doesn't fill with soot the way the old cars did.

    VW broke the law and should be punished, but this isn't the BP oil spill.

    • The fact of the matter is that the government regulators are keeping the overall level of emissions higher than the market is trying to provide. []

      Some inside baseball: Mazda has been trying to get its Sky-D diesel engine EPA-compliant (while also customer-viable) for the past two years, without success so far. You are denied this 50-plus MPG (and extremely clean) diesel because of the particulate jihadists in Washington.

      They're the enemy of the environment, not its friend. But you have to be willing to follo

      • by hey! ( 33014 )

        The fact of the matter is that the government regulators are keeping the overall level of emissions higher than the market is trying to provide. []

        I suppose that's one possible spin to put on matters, but it's not Mazda's spin. They claim that the introduction of the new engines has been delayed because of new, more stringent testing procedures put into place by the EPA in the wake of the Volkswagen scandal.

        So, either (a) you are right and the government is deliberately trying to increase the pollution to higher levels by preventing consumers from buying clean engines; or (b) you are wrong and the government is actually trying to reduce pollution by

    • If you really want to know how bad things actually are, see this 32c3 talk [] from people who work in the industry.
    • by j-turkey ( 187775 ) on Monday January 04, 2016 @12:47PM (#51235291) Homepage

      But nobody ever mentions the actual level - which is pretty damn important because 40 times 1 part per thousand is a lot more significant than 40 times 1 part per trillion.

      The actual levels are posted here [].

      Here's the long and short of it:

      Jetta (LNT system):
      EPA Limit: 0.043 g/km
      EPA Dyno Test (cheat number): 0.022 g/km
      WVU Test (actual number): 0.61-1.5 g/km

      Passat (SCR/Urea-based system):
      EPA Limit: 0.043 g/km
      EPA Dyno Test (cheat number): 0.016 g/km
      WVU Test (actual number): 0.34-0.67 g/km

      These emissions levels are in g/km, which is pollutants over distance (which can probably be converted to time, if you dig around the actual study [] to find average speeds attained, but I'm supposed to be working right you can try to dig that up on your own :). However, I do not believe that these numbers can be converted into actual pollutant volume (e.g. PPM/PPB/PPT). Perhaps you can scavenge that from the WVU study's raw data. I'd be interested in what you find.

      I am also interested in finding is a trend in the NOx regulation in the US. I've dug around a bit, but have not yet found it. E.g. - did the actual NOx levels meet previous standards? Are the current standards that VW had to cheat to get around unrealistic? Beyond this, the wiki article does cite some projections regarding the number of deaths that have been/will be caused by the cheat, but I'd like to have a better perspective than that.

  • by I4ko ( 695382 ) on Monday January 04, 2016 @11:38AM (#51234721)
    So what, Diesel is much more effective than gas cars. You can go 3 times the distance on same volume of fuel. A good engine has less CO2 compared to the trucks most of America drives. America has a skewed system of protecting local auto industry, they basically don't measure CO2 at all, they care about a short living, harmless (because of the short life) NO. Think about it - a large GMC van/suv on a truck frame, with 4 or 6 liter engine, it is much more polluting than a small 1.5/2l not so "clean" diesel. You have to think long term - about greenhouse gases. NO is not a greenhouse gas, CO2 is.
    • by Luthair ( 847766 )
      You could also make the reverse argument that Europe 'protected' their car industry by focusing on displacement. The reality is that both regions tailored their regulation over time to fix what they felt were problems. In North America we had a smog problem, part of our regulations were tailored to fix that and were pretty successful, hence we haven't had to introduce alternate-day driving bans as they have had to at times in Paris.
  • by QuietLagoon ( 813062 ) on Monday January 04, 2016 @11:38AM (#51234725)
    ... nonexistent.
    • NOTHING we do is "clean" if you think about it. Riding your bike and walking are all environmentally messy at some level.
      • Actually it's messier. Take into account the calories used for that hike and what fossil fuels had to be burned to get whatever you ate to be able to invest those calories and you'll start to weep.

        Someone has to foot that carbon bill.

        • by Alioth ( 221270 )

          It's a hell of a lot less than driving a car the same distance.

          Including all the costs (including the CO2 cost of making the bicycle, its consumables such as innertubes and tyres) plus the energy burn of the bike rider (including the CO2 cost in making the food), the result is about 21g CO2 per km travelled.

          Making the same calculation for a typical passenger car will show the total to be for a car to be about 160g CO2 per km travelled.

          The only motorised transport that comes close to the cyclist is the Frenc

      • Riding your bike and walking are all environmentally messy at some level.

        Won't somebody think of the ants!? All they got is a center for ants who can't read good and wanna learn to do other stuff good too.

  • The article centers on problems with Volkswagen's system, but how well does Daimler's BlueTEC system perform?

  • by Anonymous Coward on Monday January 04, 2016 @11:43AM (#51234763)

    Wow...hyperbole much?

    • Wow...hyperbole much?

      Oh Never! Why do you ask?

      This is a standard environmentalist tactic, using over stated affects to imply something, then making an emotional argument out of it.

    • I think the word devastating is quite apt. Air pollution from road transportation causes early death of some 53000/yr in US [1]. Diesel pollution probably supplies some disproportionate contribution.

      1. []

  • by nimbius ( 983462 ) on Monday January 04, 2016 @11:49AM (#51234817) Homepage
    Before taking a job in systems administration, I used to hold a CDL and drive regional/long haul for a trucking company. Everything we had was, of course, diesel because we run mostly on highways and at fourty tons our speed isnt a huge priority. in fact, we sometimes drive under the speed limit to make up mileage/save fuel based on projected consumption. the diesel car, for all its promises, is a break-even proposition at best.

    speed: outside of a few concept sports cars, diesel isnt about speed but torque. in trucking we compensate by turbocharging our engines, to make the lives of normal drivers easier. without turbos it would take ten minutes or more to get up to speed. the tradeoff is bad mileage.
    coldstart: cold start problems will always exist. for those of you in minneapolis or duluth, I see you shopping for the same antigel treatments and fuel additives for your audi that I use on my freighliner, and the truth is theyre awful for emissions and even worse for mileage. emissions systems are often programmed to detect and correct for them. they dont always work in the coldest weather, and consumer autos dont have fuel tank heaters or radiator louvres.
    "cleanliness": no. hell no. On my Freightliner CL Columbia truck, I had no less than 6 gauges for the emissions system. everything from exhaust backpressure to air-in temp, exhaust temp, and temperature monitors on the scrubber DPF CV. sometimes id sit idling for 15 minutes just to make sure my emissions layout was "green" before taking off, because if its not ill blow smoke for miles down the highway. urea tanks and injectors need to be filled and cleaned respectively at regular intervals, and in long haul trucking this is a no brainer. we have a very user friendly interface for monitoring and planning refill. but car drivers? do you really want to worry about the car dropping down into "limp home" mode when you forget to top off the tank? it could strand you on the highway at 24 miles per hour.

    finally, theres the godless process of smogging. what might fly in one state, wont in another, and as more states adopt emissions standards that require smog checks, more of these older diesel cars will fail outright. for most trucks, if you can smell the diesel smell, you wont pass.
    • by swb ( 14022 )

      Aren't most passenger diesels turbocharged these days? They still seem to get crazy good MPG figures, and the marketing and car reviews seem to praise their torque for real-world acceleration (what's the old saw -- you buy HP, but drive torque?)

      I thought that antigel additives got added at the refinery for winter states like Minnesota so adding additives wasn't really necessary. My dad owned a truck parts business and they used to hawk an additive, but I don't know we ever sold much if any of it. I also

      • by nimbius ( 983462 )
        most, if not all passenger diesels have been turbocharged for about 30 years. Datsun was one of the only companies not to do it. imho they get good mileage because of their weight/displacement ratio and aerodynamics, or just flat-out lying. the problem Id venture is that a new turbo will always feel smart and strong, but give it 160k miles and without a resurface or rebuilt, the burnt-down fins will cause performance to suffer.

        Antigel is crucial. not for 30-40 degree cold starts, but for the bone-cra
      • by SydShamino ( 547793 ) on Monday January 04, 2016 @12:20PM (#51235059)

        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.

        • by seoras ( 147590 )

          Ditto. Just filled my 2 year old Citreon GP with 10L of AdBlue just as it's clock turned 30,000Km.

    • Interesting and informative, but no mod points.
    • outside of a few concept sports cars, diesel isnt about speed but torque.

      It's about low-end power, not torque.

      Unfortunately, in the US the diesel engines that exist there are there out of necessity because no one could shove a gasoline engine in. The economics and consumption are just too obvious. Beyond that, very little investment, if any, has been made in diesel in the US. A European car diesel takes a surprisingly short amount of time to warm up. Certainly in the 90s, you only used a diesel car if you were on the road permanently as a rep or something. Lack of enthusiasm

    • by GuB-42 ( 2483988 )

      In Europe, gasoline is taxed more than diesel fuel. The goal was to tax cars more than trucks, the diesel car is basically a tax exploit.
      Diesel is also more efficient, which is, again, a significant advantage when taxes make fuel expensive.

    • Advantages of diesel:
      1. Fuel economy. Thanks to high fuel prices in Europe, fuel is a major component in the TCO of a car. Switching to a car that uses half the fuel is a no-brainer (depending on 3.).
      2. Drivability. Thanks to 1. everybody drives compact cars with small engines. Small unturbocharged petrol engines have little torque, so in mountainous areas they're crap to drive and everyone switches to a compact turbodiesel. Same for people who need to tow anything.
      3. In Europe, governments use taxation of

  • by segedunum ( 883035 ) on Monday January 04, 2016 @11:55AM (#51234867)
    As usual, you have politicians and vested interests talking out of their arse and lurching from one crisis to another. The vast majority of pollution in any city is produced by a few hundred thousand large trucks, lorries, buses and vans which are usually given emissions exemptions. Good luck stopping them from running diesel. Banning diesel cars will do nothing for this (especially modern diesel cars which really are much more efficient even allowing for VW's stupidity) and might well make the situation worse. A lurch back to petrol/gasoline for Europe means producing more of a fuel that takes more energy to produce and transport as well as having to burn more of it by volume. Nobody seems to ask just how much in the way of emissions are produced on a journey outputting a certain amount of power.

    We're likely to hear more anti-diesel rhetoric in the future. With the ever falling oil price and no floor to it in sight petrol/gasoline is simply going to be uneconomical to produce at some point. The only thing to do is to then try and ban the cheaper alternative through laws and regulations. There's a bit of distortion going on at the moment.
    • As usual, you have politicians and vested interests talking out of their arse

      Actually, this is just the opposite. The car industry in Europe is heavily leveraged towards diesel. European politicians don't want to put their domestic car makers out of work. They are addressing this problem DESPITE their vested interests, because it's gotten THAT BAD. You have all those historic landmarks covered in soot and requiring tremendous maintenance from the damage from the air, alone.

      Banning diesel cars will do noth

  • So how is reducing them going to help meet the Paris climate deal?

    It should also be noted that standard gasoline cars also emit much more than tests indicate, and as any driver knows seldom match the stated mpg claims.

  • by Xelios ( 822510 ) on Monday January 04, 2016 @12:29PM (#51235145)
    There was a fantastic talk [] at this year's Chaos Computer Club in Hamburg delving into the reasons behind "Dieselgate", including insights into the car industry itself and findings from disassembled ECU code. Part of it shows exactly how and why the NOx scrubbing technology was purposely disabled during normal driving. It does work, it just wasn't allowed to do its job, presumably to lower maintenance costs for the customer. And as the talk shows this decision must have involved hundreds of people including upper management, not just a couple of engineers.

    The testing methodology for emissions is a shambles and has been cheated by every car manufacturer for decades now to varying degrees. If we're serious about fixing the emissions problems then this is the first place that needs attention. I believe you can make diesels cleaner, but it costs money. Fix the tests to force these emission standards to be applied in normal driving and then let the consumer decide if the added cost is worth owning a diesel. In fact we need to fix the tests regardless, if only to get a proper look at the real state of emissions across the board.

    But seriously, the talk is well worth watching.
    • by Lennie ( 16154 )

      I haven't watched the talk yet. I've been to busy watching other 32C3 talks. :-)

      But I do know that just after Dieselgate came out, some of the news in the Netherlands was that the testing lab in our country (which does this for otherEuropean countries too) had already figured this out at least a year earlier.

      Their report showed that out of 16 models tested 14 failed a slightly more realistic test. So they were already busy helping to change the rules at the European level to get proper realistic testing.


    • by Alioth ( 221270 )

      I thought while one of Volkswagen's Cxx people was busy throwing its software engineers under the bus that this indicated:

      * either VW had absolutely terrible, terrible software auditing, and the executive was effectively unwittingly condemning his own company for such shoddy practises.
      * or he was lying.

      There is absolutely no way that a "rogue engineer" as the guy put it could do this kind of thing and get away with it, even if VW's software auditing is indeed terrible. It would have taken at least the collu

  • Yes, diesel engines cost more than regular ones, but that difference has declined sharply in the past decade and what's left of the price difference of maybe 10% is easily offset by the cost of operation. Getting 50 miles per gallon of diesel is far from impossible and with a price of about 80% of regular fuel it gets even cheaper.

    As long as this is the case people will reach for diesel as long as there is no compelling reason not to. It's simply as that.

  • I love my TDI and you can suck my dick to determine the level of pollution that it kicks out. I never had it tested but I am pretty sure the new generation of TDI engines is much cleaner than any previous diesel engines before them.

  • I think that this proposal, signed by Elon Musk amongst many others, has an interesting approach: []

    tl;dr Instead of burdening VW with the huge cost of fixing the problems and fines, mandate that they invest the same money in Electric Vehicles and plant (ie economic development and jobs) in the affected states (in this case CA).
  • Years of listening to europhiles prattle on and on about the wonders of diesel cars, and stoopid 'muricans with their cowboy gasoline hotrods.

    So much for that noise. Let us know when you get your fleet fixed and burning gas.

  • If they can make Clean Coal, why can't they make Clean Diesel?

  • You can have my 2008 ML320 CDI turbodiesel when you pry it from my cold, dead fingers.

  • Come on, why haven't we seen one diesel hybrid car? Then there's zero issues about start, stop, and low-speed. Even with the price-gouging of the gas companies, that would really give you a high milage/gallon.

    And don't tell me that would be "new" technology. Go down to the railroad tracks, and watch all the ->diesel-electric- locomotives, which have worked this way since the thirties....


  • The way to go for minimizing the emissions is to build diesel-electric hybrids, where the engine only turns a generator that charges batteries. The reason is that the engine can be optimized for one RPM and load, and the catalysts can run closer to a steady state. Where the emissions spike are during transitions of power output, especially when accelerating after a period of very low output that lets the cats cool down.

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