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"diesel cars will initially be allowed to pollute more than double the current legal level" They're in trouble then because they currently pollute on average six times it..
 

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Discussion Starter · #5 ·
Lol doesn't it give you a warm fuzzy feeling inside knowing you are doing your bit. He then realises I'm breathing in all that dirtier air!!!!! Can I sue the car companies for failing to meet the requirements and their fore damaging my health at a higher level than permitted?
 

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Nothing apparently a new standard is coming in next year so these cars will be immune and they can start cheating the new system
 

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Does this affect the comparisons that keep getting quoted about coal fired EVs?
I don't know... Has anyone checked the emissions at power stations? They are probably making it up :)
 

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The problem is that for type approval a repeatable test is required - currently that being the NEDC in the EU - which is always going to differ from how the cars are driven in real life. It's therefore not surprising that real world emissions will be different and highly dependant on actual drive cycle and driving style. However all the vehicle OEMs take advantage of allowed tolerances and loopholes in the test - perfectly legally - which makes the gap even wider . Where VW differ is they deployed software to detect when on the highly repeatable type approval tests and run a different engine calibration from normal running.

In the US the test regime is much better IMHO with different test cycles to test different aspects of the vehicles performance, also there is more of an independent nature in the testing, plus random testing by the EPA which makes it more likely that any wrongdoing will be detected. In the US, the dyno load data is also a matter of public record making it much easier for independents to check results. In the EU the tests - type approval and conformity of production - are performed by the OEM which makes for much more opportunity for dishonesty. There is also no EU body that can independently verify the tests and sanction the OEM if cheating is found unlike the US.

The new tests being talked about are a new drive cycle - the WLTP - which closes some (but not all) of the loopholes coupled with a driving test which has to cover a set number of conditions called RDE. The problem again is there are still opportunities to manipulate the result and in the case of RDE the OEM defines the cycle - it has to meet the required conditions but the opportunity for optimisation is still high. In theory the new cycle plus RDE (on a voluntary basis) comes into force in 2017, but the OEMs have been lobbying hard to get in delayed and/or watered down. The RDE limits only become mandatory in 2020 if memory serves me correctly.

To be fair to the OEMs, the results quoted by the press have no meaning unless they are representative and repeatable. For example, NOx emissions from diesels are very dependant on driving style - highly transient events tend to massively increase the NOx so a real world cycle consisting of a lot of rapid acceleration events will almost certainly exceed the type approval limits, but the vehicle could still be perfectly compliant on the repeatable test which is the legal requirement.
 
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I get that the tests need to be "repeatable" for different makes and models, but how about if the test was more "real world", and not some little lap around the block, or a rolling road for the equivalent of 10 miles.

How about from the Mira vehicle testing place in Nuneaton to the Houses of Parliament, and back again, in a single day. (about 100 miles each way)

plugin Hybrids are allowed to start with a full charge (as if overnight), and they can use a rapid and/or a few hours on a destination charger before the return leg.

The manufacture can supply the driver, who will probably have a specially trained feather light right foot.

And because of the variations to do with traffic and weather, the car has to do it 7 times, once on each day of the week, but they can spread it over a 30 day period, so that a day can be repeated if there is pile up or some other unfavorable event happen on a test day. But then ignore the results for the highest and lowest days, and then average the other 5 days to give the result.

And what would be tested is ... mpg and the various emissions that actually came out.
Perhaps it might need to be repeated with some horrible big "strap on" equipment dangling on the back of the vehicle with a pipe up the exhaust to do emissions, and again without for the MPG?


I guess the official figures for my Outlander would drop from over 140mpg to around 50 or 60mpg, but I have no idea about co2 or nox.
We would see more sensible figures for the big stuff with silly little batteries, like the Mercedes S500hybrid, BMW x5h and the Volvo xc90 t8.
I can see car manufactures might become more interested in giving the option for bigger batteries in their hybrids.
 

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Lol doesn't it give you a warm fuzzy feeling inside knowing you are doing your bit. He then realises I'm breathing in all that dirtier air!!!!! Can I sue the car companies for failing to meet the requirements and their fore damaging my health at a higher level than permitted?
Good luck on that one :D.
 

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Emissions testing shouldn't be a 1-off event.
All cars should measure emissions all the time - as if it's just part of the trip computer.
So to get an emissions number for a particular model, you just drive a few of them and average the results.
When you do a test drive or car review you check your result against the advertised result.

You define tolerance, e.g. 20%
And if at any point during the car's life, emissions exceed that tolerance,
The trip computer records this fact and the car fails its next MOT.

Brands consistently failing to meet this criteria will go out of business.
If they can't build a car that can comply with this regulation
They'd better just build a car that emits nothing.
 

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I get that the tests need to be "repeatable" for different makes and models, but how about if the test was more "real world", and not some little lap around the block, or a rolling road for the equivalent of 10 miles.
Alternative , and repeatable , idea:- The vehicle is delivered to an approved test facility operated by the Licencing authority, somewhere like the Road Reseach Lab, empty of fuel, and/or with low charge in motive battery.
The Indpendent staff of the Test Facility then fuel it according to manufacturers drivers manual with measured amount of fuel, not less than 10 litres. It is then put through series of simple tests on rolling road, 1. cold start and immediate acceleration to 40 mph for 20 seconds, followed by 20 seconds static followed by immediate acceleration to 50 mph, the 1 minute static. repeat 5 times. , then 2. unplug rolling road test equipment, take onto motorway standard test track and drive at 90 kph until vehicle runs out of both battery and fuel. Produce results.
Just a rough idea, needs agreement on what is cold start,what air temps and humidity are used and what barometric pressures are in test zone.and what fuels the test centre should provide. But I suggest something along these lines would be fair both the Manufacturers and more importantly the buyer, and pedestrian.
 
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