Friday, May 26, 2017

Credit Where It's Due. Kudos to Volkswagen.

The Boys from Wolfsburg will always be associated with the diesel emissions scandal. It began when VW was caught cheating. When undergoing tailpipe testing its "clean diesel" engine proved remarkably clean. When in ordinary use, however, the engines produced legendary fuel efficiency and impressive power only at settings that generated prohibited levels of toxic nitrous oxide emissions.

VW went into full bore damage control mode. It offered to buy back the cars from disgruntled owners along with a modest settlement for damages. Owners also have the option of having their cars "fixed" - i.e. the cheating software replaced - and just take the damages.

Here's the irony. A lot of automakers produce diesel cars or trucks and most of them are also cheating, some far worse than Volkswagen. Yet, perhaps because this is now a more or less universal problem, the others haven't been prosecuted or forced to institute buybacks or recalls.

This week it became General Motors' turn for its Chevy Silverado and GMC Sierra pickups.

"This is a shocking discovery, and a really big deal because the [nitrous oxide] limits for these big trucks are four times what the limits were for the much smaller Volkswagen passenger cars and there are more of these trucks on the road," said Steve Berman.

An article in The Guardian last year reported that 97% of diesel vehicles exceeded the NOx emissions ceiling.  The exception? That would be Volkswagen.

Surprisingly, the tiny number of models that did not exceed the standard were mostly Volkswagens, the carmaker whose cheating of diesel emissions tests which emerged last year sparked the scandal. Experts said the new results show that clean diesel cars can be made but that virtually all manufacturers have failed to do so.

The EA analysis found that just one of the 201 Euro 5 diesels tested – a Skoda Octavia – did not exceed the official limit on the road. Over a quarter of the Euro 5s pumped out at least five times the official limit, including models from BMW, Range Rover, Mercedes, Nissan, Renault and Vauxhall.

Of the 62 Euro 6 models tested by EA, seven did not exceed the official limit in real-world driving: four Volkswagens, a BMW, an Audi and a Skoda. However, an Audi A8 and a Fiat 500X were found to emit more than 12 times the official limit, while a BMWX3, a Volvo S60 and a Vauxhall Zafira were among models emitting more than six times the official limit on the road.

Another report from today's Guardian warns our regulators are not making much progress.

Diesel cars that emit up to 18 times the official limit for toxic pollution when taken on to the road are still being sold, 20 months after the emissions scandal erupted and amid an ongoing air pollution crisis.

In real world conditions, the Nissan Qashqai produces 18 times more nitrogen oxides than the official lab-based test allows under EU directives, while Nissan’s Juke pumps out 16 times more NOx pollution than the limit, according to data from vehicle testing company Emissions Analytics seen by the Guardian.

Further data reveals Renault’s M├ęgane and Captur models both produce 16 times more NOx when on the road. Overall, the data shows that 80% of new diesels on the market in the last nine months fail to meet the official limit when on the road. upgrades from manufacturers would quickly and significantly cut the emissions of many existing diesel cars: “What you can do is turn up the effectiveness of the emissions reduction technology – it’s almost like a volume knob – and that is a software change. If they turn up the volume, you have a clean car.” But apart from cars from VW, which was caught blatantly cheating, few vehicles in Europe have been recalled.


Anonymous said...

This week it also became Fiat Chrysler's turn to be sued over diesel emissions cheating software. The US Justice Department alleges that Chrysler put cheating software in nearly 104,000 diesel Ram pickups and Jeep Grand Cherokees from the 2014 to 2016 model years.

Frankly, I'm surprised Jeff "Selfregard" Sessions gave this the green light, but since it doesn't involve minority civil rights, Russia or corruption in the White House, I guess it's good to go. Canadian regulators and prosecutors are, of course, asleep at the switch.


The Mound of Sound said...

Cap, give Sessions a break. You know that Jeff and the rest of the Trump boys are working as hard as they can to dismember the EPA. Some day, they hope, this sort of thing will just be a bad memory.

Toby said...

If humans are around another 200 years they will look back in wonder at our use of diesel. It is a noxious fuel that is a major cause of urban pollution and breathing difficulties.

The Mound of Sound said...

Yet we've seen, Toby, that diesel engine technology can be clean but that comes at the expense of power and fuel economy.

Toby said...

Not as clean as I'd like. Since I am one for whom diesel exhaust causes choking I would happily ban it from all fuel use.

As far back as the Tucker 48 debacle we have known that America's Big 3 automakers try to protect their turf through lobbying. The recalls forced on Toyota and Volkswagen, while legitimate, certainly had the Big three cheering on the sidelines. Yes, all car manufacturers are likely to be cheating on diesel emissions and fuel economy. Will Big 3 diesels be censured as badly as Volkswagen? I doubt it.

Anonymous said...

The "clean diesel" is an oxymoron.
There are NO clean diesels.
While it is possible to clean the diesels' tailpipes, the cost of doing it (plus associated expenses in removing sulphur from diesel fuel, higher cost of diesels etc.), outweigh any benefits vs gasoline.
BTW, the Oxford street in London crowded with diesel buses has TOXIC levels of NOx and PM2.5...

Anonymous said...

Well, for a start, nobody is worried about nitrous oxide emissions. Nitrous oxide is laughing gas, and nitrous refers to the two nitrogen atoms in the molecule, N2O2. Learned that in Grade 10 chemistry in 1960.

The actual problem is nitrogen oxide emissions, commonly written NOx, where a single nitrogen atom is in a molecule with one, two or more oxygen atoms.

Only the technically doltish refer to nitrous oxides as pollution, a common error from those unable to absorb what they read and then just assume. Check out NOx on Wikipedia for the basics so people who do know don't laugh at you if you should happen to write technically illiterate gibberish. And no, saying "You know what I mean" doesn't cut it as an excuse for being uninformed. It's just wrong, or shall the crowd rise up and pretend to be like Trump who cannot be bothered with details? Damn those intellectuals! Progressives should at least try to get it right if we still believe in science, no?

NOx reacts with sunlight to produce ozone and smog. That's what's ruining European cities like London, Paris and Milan. Once again I suggest the basics are on Wikipedia.

Nitrogen oxides are formed in combustion with plain old air, which is 79% nitrogen to begin with. The higher the temperature of combustion, the higher the levels of NOx generated, BUT also the higher the combustion thermal efficiency. Diesels inherently run hot combustion, they are compression ignited - and they produce a lot of NOx. To mitigate that NOx production, diesels are made inherently less efficient than they would otherwise be, by reducing combustion temperature. This is done by recirculating cooled exhaust gas into each cycle. Chuck away efficiency.

Then there are NOx catalytic converters that chemically reduce some of the remaining NOx. This VW claimed in 2009, was all you needed, their new magic NOx catalytic converter. And what other diesel manufacturers marvelled at - they couldn't meet standards VW claimed to meet with just an NOx converter.

BM continued

Anonymous said...

BM continuing NOx

Even VW follows the rest these days - the NOx converter is followed by Selective Catalytic Reduction SCR, where ammonia in the form of urea (purchased separately and kept in a separate tank - Mercedes calls it AdBlue) is added to the exhaust. You can add enough urea to get rid of NOx almost entirely. Yes! You just need to add about as much quantity of urea as diesel in the first place. So this is where the diesel manufacturers cheat the tests. They identify that it is indeed a test by noting the duty cycle and add urea in great quantities. Hola! No Nox! Pass. But on the road they add nowhere near enough urea, and you get the situation where VW diesels were over-emitting regulated NOx by a factor of 40, particularly on acceleration or when producing high power such as climbing steep hills. (The University of Leeds found full-sized buses emitted less NOx!) Or when the temperature was over 30C or less than 10C, they gave up using urea entirely. Massive pollution. I cannot visit England any more - my eyes cannot take it and swell up.

Because direct injection produces tiny particulates in the exhaust, nasty tiny soot invisible to the eye that clogs the linings of our lungs, the final pollution control device on a diesel is the DPF, diesel particulate filter. I'll spare you the details of how these Rube Goldberg devices work because they often go wrong, but their use requires extra injections of diesel to work, kind of like pulling the choke in the old days. The exhaust is then rich with raw hydrocarbons which are burnt in the furnace-like DPF, getting rid of particulates of raw carbon in the process that have been previously stored on a wire grid. This cycle operates every few hundred kilometres when the soot buildup produces too much exhaust backpressure.

Diesels are kaput as a engine system for the future when you have to go through these extraordinary measures to make them work without excess pollution, I don't care what Herr Doktor Professor Dipl Eng D Zetschke, Chairman of Mercedes says. He's just trying to save his ass along with the rest of the NOx liars.

I am an engineer, not an industry expert, but I have enough background and have studied it enough to have some clue what I'm yammering on about. I've followed the VW scandal very closely indeed. Most people cannot even identify the difference between nitrous oxide and nitrogen oxide, let alone have a clue where the real problem is. Generalists fail in their commentary if they don't have a solid basis of understanding. Hence this missive.


The Mound of Sound said...

Hi, BM. Thank you for your explanations and insights. Most of us lack your knowledge and grasp. Much appreciated.

Anonymous said...

Correcting the typo for those who will not look at the chemistry pages:
"Nitrous oxide is laughing gas, and nitrous refers to the two nitrogen atoms in the molecule, N2O2"
Actually it is N2O.

AniO said...

As a Vw diesel owner, I must say I give no credit to the company at all. They didn't own up to wrong doing, they were merely the first to get caught. They are not fixing the fraud cars , except for the 2015 models, which they have now begun to sell, even though they are known to be non/compliant. We bought a VW because we were led to believe we were being environmentally responsible. We are furious that we weren't. We have replaced it with a Chevy Bolt, a fully electric vehicle but this has cost us a bundle that VW's pathetic (and bureaucratic) compensation plan has done too little to address. VW has also turned the whole debacle into a marketing opp, calling us repeatedly to urge us to "upgrade" to a gas vehicle. As if.

The Mound of Sound said...

I'm in a similar situation, AniO, and for the same reasons. Where I give VW credit is in how they're handling the situation contrasted with other manufacturers, European, Asian and North American.