How will the government cut Nox air pollution?

Will they now put massive tax hikes on diesel cars..
Build a high speed rail link..
Nothing for another 5 years..

Or a crazy idea might be to get vehicles off the road with Massive investment into proper cycling infrastructure..

nothing that isn’t already happening, it’s just that the effects of it are taking a lot longer. It’s a region specific issue, so unless all old diesels are stopped from entering London within a 30mile radius, f’all will happen. New diesels are not the problem, per see, though the introduction of bio-fuels is a massive contributor..

Diesels will become much more expensive to run.

So, VED will go up, and so will tax on fuel. Petrol will be back!

They’ll probs just stop testing for it ,then it stops being a problem. 😆

I think once I fit a new fuel injector it’ll all be fine. OTOH I’m cutting down global warming by blotting out the sun when I start the thing

If they drop off a few thousand litres of veg oil for me and my landrover, I can single handedly obliterate the NOX levels in Malvernistan overnight 🙂

New diesels are not the problem, per see, though the introduction of bio-fuels is a massive contributor..

That’s not true – modern diesels do not perform anything like as well as they are supposed to.

Sui – Member

New diesels are not the problem, per see

‘new’ diesels make finer particles than old ‘sooty’ diesels.

and the thing about particulates is, smaller = worse.

anyway, this:

Nothing for another 5 years.

Do the same as they do in the US where, despite nit giving a shit in many areas of environmental legislation they are strict on NOx.

Petrol cars have lots of EGR which is why they seem slow for large displacement engines. No diesels met the specification between 1997 and I think 2005 or so when VW came out with selective catalytic reduction. This is another cat in the exhaust, and you need to use adblue like lorries.

The good thing though is that you no longer need notoriously problematic EGR, and I think you can advance timing a little so you get greater combustion efficiency. Engine should be less sooty and more economical.

Not a lot, they’ll see it as a tax rise opportunity but not increase it enough to resolve the issue. They won’t want to kill the golden goose.

New cars will need the AdBlue additive that trucks use to reduce NOX.

London will stop allowing diesel cars without AD Blue going in to the city at some point.

Diesel still makes a lot of sense over petrol cars for long runs up and down the motorways so it won’t be going anywhere too soon.

The good thing though is that you no longer need notoriously problematic EGR, and I think you can advance timing a little so you get greater combustion efficiency. Engine should be less sooty and more economical.

Not claiming to know much about car engines but I thought that Diesel engines just compressed the fuel until it got so hot it spontaneously ignited . If that is true surely you can’t advance the timing . I could possibly be talking rubbish here .

The highest reading in Glasgow is from Hope St at Central Station. Almost all the traffic there is buses and taxis as private cars are banned. So maybe bus and taxi emissions are needing to be targeted. Though bringing bus regulation back might also help. Almost every bus route seems to go through the city center. Having a frequent electric shuttle bus service around the center connecting to diesel buses kept outside the city center would probably get Hope St down to safe levels at a stroke. How often are taxi emissions tested?

http://www.understandingglasgow.com/indicators/environment/air_quality/city_comparisons/no2_levels

Water injection also lowers EGTs without the associated poor combustion effects of an EGR. Marine applications are very mature and Marpol 6 is about as strict as it gets.

If that is true surely you can’t advance the timing

The injection timing… Diesel engines compress the air til it’s hot, then inject liquid fuel into the hot air where it starts burning on contact. This is why they smoke, because the droplets of fuel burn from the outside in, only the outside is in contact with the air. If the temperature drops (as the mix exits the exhaust) before combustion is completed, or the oxygen runs out,then the droplet isn’t burned all the way and you get a soot particle. Petrol is vapourised into a gas and the molecules are side by side with oxygen molecules so this isn’t an issue.

Re water injection, yes it lowers combustion temperature but that reduces efficiency. SCR allows high combustion temp because you can produce all the NOx you want, you clean it up in the cat. I think anyway.

Replace diesel with gas, as in methane gas. Circa 90% reduction in NOx and SOx and particulates too. Gas buses, gas trucks delivering into towns – all available and all quieter than diesel too.

Company Car Tax Benefit in Kind (BIK) rates

Looking at how diesel BIK is going to start matching petrol BIK in the next couple of years, I’d suggest they already are jumping on the NOX bandwagon. Glad I’ve only got my oil burner for two years. Back to petrol after that as the lesser fuel efficiency will be balanced out by the cheaper purchase cost and BIK will be the same.

Hybrid petrol…

Car industry representatives are at this moment no doubt lobbying govt hard to stuff billions of pounds worth of subsidies for electric cars down their throats

Replace diesel with gas, as in methane gas. Circa 90% reduction in NOx and SOx and particulates too. Gas buses, gas trucks delivering into towns – all available and all quieter than diesel too.

Where will we get that from then? You do realise domestic supplies are all but exhausted in real terms right?

Molgrips – I see, sounds interesting, will have to do some reading. Your point about incomplete combustion is also why fuel systems are getting to higher pressures all the time as it aids in atomisation.

If Im honest though diesel really is a poor fuel, the time will come when it just gets pulled completely like they did with leaded petrol.

Yep higher pressure = smaller droplets = better burn.

Diesel has advantages – it’s energy dense, and because it’s not so volatile you can use much higher compression which increases efficiency, from heat engine theory, the stuff I couldn’t force myself to listen to in uni.

I believe there is work being done on compression-ignition petrol and gas engines. If you fill a cylinder with combustible gas/air mixture and compress it it’ll explode but unpredicably, and you can’t control where it starts to burn so you get all sort of shockwaves and badness that damages the engine. But apparently they are working on it

http://en.wikipedia.org/wiki/Homogeneous_charge_compression_ignition

And an alternative:

http://blog.caranddriver.com/hyundai-developing-gasoline-burning-compression-ignition-engine/

The highest reading in Glasgow is from Hope St at Central Station. Almost all the traffic there is buses and taxis as private cars are banned

You can drive a car past the air quality monitor I think? You have to take the next left though, can’t go further up Hope St. You’re still right most of the traffic is buses & taxis.

Exxon think that light duty diesel usage will reduce, but heavy duty truck diesel usage will increase by 2040

http://cdn.exxonmobil.com/~/media/global/Reports/Outlook%20For%20Energy/2015/2015-Outlook-for-Energy_print-resolution

If only there was some sort of cheap, clean, emission free urban transport vehicle that was so simple to operate that even an 8 year old child could use it to zip back and forth across a city.

squirrelking – Member
Replace diesel with gas, as in methane gas. Circa 90% reduction in NOx and SOx and particulates too. Gas buses, gas trucks delivering into towns – all available and all quieter than diesel too.
Where will we get that from then? You do realise domestic supplies are all but exhausted in real terms right?

Gas and LNG is a global market and if shale gas takes off… Plus there’s renewable gas in the form of biogas from sewage treatment, food waste plants, etc. etc. The amount of gas required for transport purposes to clean up the air quality in cities is small beer compared to the quantities used for heating homes/businesses and generating electricity from gas fired power stations.

I reckon if you fit a leaf blower just after the catalytic converter it will add a lot more air to the mix thereby reducing the proportion of NOX and passing the test.

Simple

Yes its a global market but how do you think we import it? Thats what Im getting at.

You say its small beer but Id be inclined to disagree. There are ways however, to mitigate its impact on total consumption such as converting all fixed supplies to hydrogen (it is already possible to supplement existing supplies without burner modification) but the next problem would be generating sufficient quantities and ensuring the infrastructure is fit for purpose.

irc So maybe bus and taxi emissions are needing to be targeted

Here’s the thing about NOx emissions: They are generated at high pressure and temperature (because it needs those conditions for the nitrogen in the intake air to bond with the Oxygen).

And here’s the thing about passenger cars in cities: They aren’t running under high load conditions. Modern passenger car diesels can produce 100s of BHP, but in town, you are using about 5. At such low loads, your passenger car diesel ISN’T generating any NOx! (unlike that massive heavy bus/Truck that keeps stopping and starting and has something like 25x as much tailpipe emissions……….)

Funnily enough, when the London Bus drivers went on strike, even though more people drove private cars in london, that day had the lowest NOx emissions………..

Squirrel – how do we bring in diesel now? It’s no different, but gas burns cleaner. Much cleaner. And where are you getting your hydrogen from?

I am talking about trucks and buses in towns and cities here, not wholesale replacement.

Are diesel cars worse than petrol ones over the lifetime of the car?

And here’s the thing about passenger cars in cities: They aren’t running under high load conditions. Modern passenger car diesels can produce 100s of BHP, but in town, you are using about 5. At such low loads, your passenger car diesel ISN’T generating any NOx

Why? The fuel/air mixture still has to ignite under adiabatic compression, so it’s still going to get hot. << Genuinely interested.

Hybrid buses should have a dinky diesel engine permanently driving a battery pack and capacitor bank, not these noisy bloody stupid things that turf out black smoke and other crap.

At such low loads, your passenger car diesel ISN’T generating any NOx!

Really? The pressure in the cylinder is still pretty high, even though the turbo might not be working. Is it that the EGR is that effective at low load? Can’t be bothered to trawl though the research papers this turns up tho 🙂

Are diesel cars worse than petrol ones over the lifetime of the car?

Interesting point. According to some people (and TINAS off this forum) we use more diesel than is naturally present in crude oil, so we have to crack the heavier fractions which takes a lot of energy. This could end up using more energy than saved with the more efficient engine.

Hybrid buses should have a dinky diesel engine permanently driving a battery pack and capacitor bank

AKA parallel hybrid. And I think they do tbh.

They probably haven’t got a clue but they’ll come up with some cockish policy based on a load of codswallop. Within 100 days of taking power of course.

CNG its the future, ask the Nigerians

True, we do import diesel but we also have the capacity to produce it domestically, something we are rapidly losing in gas.

Hydrogen can be extracted very easy given enough power, you can generate that however you please but if I was honest then nuclear would be my go-to. Once renewables reach a point where they produce an appreciable surplus then electrolysis would be a good sink but until then we need something reliable that isn’t simply moving the sustainability problem elsewhere.

I didn’t realise you were talkinge exclusively about heavy users though if that’s the direction then any gas is suitable really, it’s just a matter of making it transporatable (which hydrogen really isn’t in the quantities needed to be practical).

Personally I’d sooner see the whole system replaced, it would be a massive undertaking but it would be easy enough to just containerise everything, dirtribute via railheads and run it into town using electric trucks. You could even run trains of automated containers at certain times of day or using special routes avoiding traffic as they do in container terminals.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/388195/Emissions_of_air_pollutants_statistical_release_2014.pdf (Page 12)
Replace and close combustion power plants. Accelerate Nuclear builds, wind and solar, promote home generation and a few other things.

Great in thoery but with CCGT being the quickest return on any investment the chances are minimal.

I do completely agree with you though.

For reference
http://www.drax.com/media/31605/Environmental_Performance_Review__2012.pdf
Drax power station contributes 10% of the generation totals for NOx and about 3% of the national figure. Some of these things do give a quick win…

All the PM2.5-10 still makes me chuckle as when I used to spend my days doing emissions monitoring the honest science was that although we could monitor and measure Pm10&2.5 as part of total particulate the PM tended to behave in such ways that it would combine and split up so 2 tests measuring the same source at the same time could come up with very different PM size results. The answer is important but not sure how much the science has caught up with the tech.

Considering how good cars like the VW Up are already I can’t believe we won’t be largely electric within 20 years with much of the electricity produced without burning stuff.

Combine that with increased cycling/walking, improved public transport that doesn’t dump a ton of soot every time it pulls away and we should be about there.