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."

Comments

Hardly surprising

[Viol8]

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.

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 thats more equipment, more complexity and more expense.

Re:Hardly surprising

[mjwx]

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.

Re:Hardly surprising

[Thelasko]

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.

Re:"Clean diesel" is an oxymoron

[houghi]

In Europe (at least in Belgium) these cars would not be allowed on the road anymore. Does not matter if you are owner 1 or 10. Every two years the car needs to be tested and if it fails, you are not allowed to drive the car anymore. You will not get insurance and if you drive and get caught with a car that is not allowed on the road and no insurance, things go bad pretty fast.

So the maximum amount you could drive it till it falls apart is 2 years, with an average of 1.

What most people do at that point is sell them to somebody who will not bring it on the road in Europe (otherwise, another test) and export it to Africa.

Re:Electrics

[KozmoStevnNaut]

Emissions controls on a big stationary power plant is much easier and much more efficient than emissions controls on cars.

Re:What? No, this is wrong!

[Anonymous Coward]

Where did you go to school?

The USA Constitution says that the rights of the Federal Government are severely restricted, that is, they are listed in the USA Constitution.

The rights of the people (individuals as 1 or a group such as a State) have severely UNrestricted rights.

The Bill of Rights ONLY lists some of the unrestricted rights of the individual or states. The fact that the Bill of Rights does not address a particular right that an individual has does not mean the individual does not have that right. To the contrary, the individual, under the USA Constitution, has the vast majority of rights and these rights need not be listed for the individual to have those rights.

History shows that the USA Federal Government has continually and constantly disregarded and restricted the rights of the individual as often as the Federal Government can. And without regard to what is Constitutional, legal or illegal.

The USA Supreme Court has limited the rights of the local and state Governments in most cases that it has ruled on. The local and state Governments do not have unrestricted rights.

This is what you should have been taught in the Government Schools (I was).
The is what you should have read, the USA Constitution, in the Government Schools (I did).
This is what you should know to pass a citizenship test.

Please try to keep up!