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Discussion Starter #1
So yet another bolt-on solution to try and fix
the problem with DERVs ( they are filthy)
by injection DEF (stored in a separate reservoir
than fuel) into the exhaust.


Looks like refilling the reservoir is going to be costly.
Ironic seeing as thought it is almost literally a solution of pish.


Easier to just ban them outright?
 

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AdBlue can be bought for between £10 and £15 for 10 litres, possibly cheaper if bought in bulk by hauliers etc. About 2 to 5 litres are needed for every 100 litres of fuel. Therefore adds to the running costs of course. Consists of approx 1/3 synthetic urea and 2/3 demineralised water. Injected into the exhaust system down stream of the engine but upstream of catalytic converters reduces NOx considerably. That's what a lot of the fuss is about now, NOx. So what is so bad about trying to do something about a cause for concern? When engines are run hotter to increase thermal efficiency there's a greater production of NOx, and that includes lean burn petrol engines. Anyone who knows just a bit about thermodynamics will know that the higher the temperature of the hot source, and the colder the cold sink is, the greater the thermal efficiency of a heat engine. That is one reason why there has been much research on the use of ceramics in engines, their stability at very high temperatures, and don't think we're talking about cups and saucers here either!
 

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Been run in trucks for quite a few years......
 

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Discussion Starter #4
It just strikes me as yet another BandAid
slapped on to mitigate what is a fundamental
issue with DERV: It's dirty stuff.

I'm sure injecting urea works effectively under lab
conditions. But what about in 5 or 10 years time?

Are we sure there'll be no unforeseen minor effect
that will blow up in our faces?

Sceptical, to say the least.
 

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Been run in trucks for quite a few years......
Exactly. Can even get it on Amazon and eBay. So how is this measure different to catalytic converters, Multiair, VVC , reduction of benzine, lead free petrol engines? When you say filthy stuff define your term. Is it really any different to other 'oily' fuels used in ships, aircraft and other engines all keeping society going? I would say there's sufficient prejudice these days to cope with, ranging from religion, faith, colour, race, nationality down to choice of vehicle manufacturer and now type of fuel used. Let's not lose sight that this latest government issue will be more to do with getting more tax than real concern. I taught about alternative energy sources for 40 years, the pros and cons, and they all have cons, even the so called "green" sources, so well before most thought there was a problem. Most of those transfer the problem to somewhere else. France is highly dependent on nuclear fuel, the problem has been transferred to the future, and where are many of the nuclear power stations? On the coast or on the borders with other countries. The basic problem is that we have become dependent on huge amounts of energy,over most of the globe, and would be extremely reluctant to change that dependency in any real way.
 

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Discussion Starter #6
Filthy as in urban pollution levels going through the roof since we switch to DERV.
Including having odd/even numberplate days and pollution alert imposed speed limits
where you end up stuck at 70 or 90kph instead of 130.
 

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Discussion Starter #9
Ah correlation doesn't necessarily imply causation?



No, I think it's been fairly well documented that the rise in particulate pollution
levels in France (with >90% hydro & nuclear generated 'leccy) are down to
DERVs.
 

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Sounds as though measures have been put into place, given time it will be interesting to see if there's a reduction in levels or other problems arise. Not often realised that petrol engines also produce particles albeit of a different size. One reason why higher temperatures are needed is that the carbon particles are oxidised, leading to to the NOx levels increasing too. The AdBlue system addresses the NOx issue, the products being nitrogen and water. Ok, lots of add-ons to produce "acceptable" levels of carbon dioxide, PM 10s and NOx but I think that the solution (an over-worked word these days) is not to throw out the baby with the bath water! Let's face it the advocacy of electric vehicles overlooks the associated issues of battery components, the mining and refinement of the elements, the production of electricity in power stations, hydro (vast quantities of concrete used in construction and the production of cement produces carbon dioxide) or by PV cells even. How long before governments state that these are problems and need taxing and counter measures?
There are all sorts of problems with energy production and use, and the action on diesel is an easy way of giving the illusion of doing something about the problems in the short term, but ignoring the long term.
 

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One of the options open to FIAT is MultiAir. It reduces NOx emissions on the petrols significantly (but to no taxation benefit because as far as Brussels is concerned "pollution" means "CO2"). The exact mechanism is unclear to me, apart from some vague "control of the air gives better control of the combustion chamber temperature" idea...

But a MultiAir equipped diesel could remove or reduce the need for SCR fluid (to the point where the urea solution could be a service topup, not a monthly consumable).
 

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DERV can be plenty clean!

DPFs take out the soot/particles, EGR systems lower the engine temperature to reduce NOx, and SCR (for example your Adblue) to mop up the remaining NOx... Combine that with higher mpg (thus lower carbon emissions) you can pick up from DERVs, there's no reason to single them out as the one and only route cause of pollution....

That being said, DPF/EGR/SCR systems all require more maintenance and can cause issues if not looked after... So it's six of one, half dozen of the other really!
 

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One major cause of PM 2.5 to PM 10 is the burning of wood. Now when I was considering buying a property in France, before the pound plummeted against the euro, most of the properties I looked at used wood predominately as a source of space heating. Now, ok, that would have been in the country, and not the cities, but certain cities such as Lyons which does suffer from elevated levels of pollutants may well be, because of the topology, more susceptible. Many cities across Europe have seen reduced levels of pollutants and not necessarily due to banning of diesels. One study I looked at for NOx levels in the USA published in 1997, found that as diesels aged the level did not change significantly, whereas petrol cars once about 10 years old , had far worse levels than when new and exceeded those of diesels. Agreed that was nearly 20 years ago. The answer is however, not as simple as banning or restricting diesel vehicles.
If you want to see just how complicated engines can get consider how Whittle's jet engine evolved into those of today.
 

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Discussion Starter #14
Yes they do still use wood fires out in the sticks for heating/ambience.

I don't think pollution alerts and speed restriction in the summer are down to
"Cheminées" but good point.


;)
 

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Discussion Starter #15

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I tried the calculator and it came up with 0 AdBlue using my numbers, 10 000km and 9 litres/ 100km. (pessimistic). At 10 litres/100km. Jumps to 100 AdBlue. Don't think the calculator has been programmed correctly.


Having had a very quick look at prices of AdBlue to see if any different from my post (#2) ranges from £20 for 10 litres down to 50 pence per litre (bulk). So where does your £1 000 come from for 100 litres. Not £10 per litre!

He wouldn't let it lie.
 

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That's interesting, as both VM's V6 (Ghibli, Grand Cherokee) and FIAT's (everything else) passenger diesels have been able to meet EURO6 without needing additives.

However, Jeep Wrangler is temporarily unavailable to order with a diesel engine, because the current VM 2.8-litre 4-cylinder engine is not EURO6 compliant.
 
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