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Nearly All New Diesel Cars Exceed Official Pollution Limits (theguardian.com)
An anonymous reader writes: The Guardian, citing a comprehensive set of data, reports that 97% of all modern diesel cars emit more toxic nitrogen oxide (NOx) pollution on the road than the official limit. A quarter of this voluminous number emits at least six times more than the limit. From the report, "Surprisingly, the tiny number of models that did not exceed the standard were mostly Volkswagens, the carmaker whose cheating of diesel emissions tests 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 new data, from testing industry leader Emissions Analytics (EA), follows the publication this week by the Department for Transport of emissions results for 37 vehicles, all of which emitted more NOx on the road than the official limit. But the new data covers more than 250 vehicles in more stringently standardised road conditions. EA found that just one of 201 Euro 5 diesels, the EU standard from 2009, did not exceed the limit, while only seven of 62 Euro 6 diesels, the stricter standard since 2014, did so. Diesel cars must meet an official EU limit for NOx but are only tested in a laboratory under fixed conditions. All vehicles sold pass this regulation but, when taken out on to real roads, almost all emit far more pollution. There is no suggestion that any of the cars tested broke the law on emissions limits or used any cheat devices. Mayoral candidates in London, the city with the worst air quality in Britain, have seized on the DfT data to call for tighter controls on polluting traffic -- including a ban on diesel cars."Caroline Pidgeon, the Lib Dem mayoral candidate, said: "The figures are exactly the reason why we need to speed up the introduction of the ultra-low emission zone so that it starts in 2018. Ultimately we will need to ban diesel vehicles from much of London and we need a mayor prepared to take these tough decisions and work with people to make these changes happen."
I am shocked, SHOCKED, that clean diesel is just another totally meaningless advertising slogan!
What it actually means is slightly less dirty diesel.
Even if new diesel cars did pass this test they'd still start blowing black soot and other crap after a number of years have passed and the car has reached owner number 3 who isn't bothering to do anything other than basic maintainance to keep it on the road until it falls apart.
The cars only have to pass a laboratory test. If that test bears no resemblance to the real world (which the EU one doesn't) then thats the fault of the people who devised it.
That would be the auto industry itself.
The problem they have in Europe is due to historic dicounts/tax concessions on diesel, they became popular with tight-fisted motorists. Even though most of these concessions have been removed, the mindset of "diesel == cheap" remains.
There is a backlash in Europe against diesels because they've been directly linked to worsening air quality in major cities.
The main problem with emissions is if you want good fuel economy and hence lower CO2 per km then you need a high burn temp. The trouble with that is a high burn temp gives high NOx. Take your pick.
The only serious solution to NOx is a urea system such as adblue as used in trucks but that's more equipment, more complexity and more expense.
You cant make diesel cleaner. It's impossible. Everyone I know who worked with diesel engines from the fitter and mechanic level to the design and engineering level predicted this kind of revelation happening years ago. Being engineers, you can imagine the level of smug they generated after Dieselgate.
To make diesel as clean as petrol, you have to refine it into petrol in the first place.
Small diesel passenger cars are really an abbreviation, which is why they aren't common in the US or Australia where we never subsidised diesel fuels for passenger cars. Diesel engines are heavier and more complex than petrols, they require turbochargers regardless (if you want to know what a truly gutless car feels like, drive a naturally aspirated diesel). The returns are less than non-turbo petrol engines of the same size, if you turbo a petrol engine, you could easily knock 25% of the capacity off and still have a faster car with the same fuel efficiency and is kinder to the baby foxes.
The only time a diesel engine is better than a petrol is when you need pulling power. This is why almost all big rigs and tractors are turbo diesels. Even decent 4x4's like a Hilux or Triton tend to use diesels, not for fuel efficiency but to pull 3 tons of bricks about using a 2.4L 4 banger.
Calling someone a "hater" only means you can not rationally rebut their argument.
Obviously, the standards are too HIGH as they currently stand, and if most of these cars, like most of our students can no longer past the tests, then we have no choice, but to lower the standards by enough so that everyone can pass and have positive self-esteem and profitable sales!!!
Easy-peasy.
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
Emissions controls on a big stationary power plant is much easier and much more efficient than emissions controls on cars.
Eat the rich.
You cant make diesel cleaner. It's impossible. Everyone I know who worked with diesel engines from the fitter and mechanic level to the design and engineering level predicted this kind of revelation happening years ago. Being engineers, you can imagine the level of smug they generated after Dieselgate.
As a diesel emissions engineer I resent that statement. The trouble with diesel is exactly as the GP mentioned. Hotter burn is more fuel efficient, but makes more NOx. SCR is the option that can provide good fuel economy and lower emissions. However, SCR is expensive and has it's own consumable.
Diesel engines are heavier and more complex than petrols, they require turbochargers regardless (if you want to know what a truly gutless car feels like, drive a naturally aspirated diesel). The returns are less than non-turbo petrol engines of the same size, if you turbo a petrol engine, you could easily knock 25% of the capacity off and still have a faster car with the same fuel efficiency and is kinder to the baby foxes.
Diesels are not very volumetrically efficient. True.
The only time a diesel engine is better than a petrol is when you need pulling power. This is why almost all big rigs and tractors are turbo diesels. Even decent 4x4's like a Hilux or Triton tend to use diesels, not for fuel efficiency but to pull 3 tons of bricks about using a 2.4L 4 banger.
Not true. Diesels are fuel efficient because they run at higher compression ratios and don't use intake throttling to control power output. Gasoline engines can be built that rival diesels in torque. However, most consumers of such products demand the fuel efficiency of diesel.
There's a lot of FUD being spread around about diesel. Yes, it has issues. But those of us in the industry had been wondering how VW was making that system work without SCR. Now we know.
If the system is to improve, emissions regulatory agencies need to audit more engines themselves rather than trust the self reported results. They also need to implement Not to Exceed limits on all engines.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".