Can diesel engines CLEAN urban air?

Can diesel engines CLEAN urban air?

A new report into the particulate emissions of non-exhaust sources such as tyres has reached a rather shocking conclusion. One of the findings is that a modern diesel engine can actually CLEAN the air it’s driving through. 

This is highly contradictory to some of the negative talk around diesel cars. The Emissions Analytics report opens the diesel discussion, saying “the truth is that they have emitted very few particles, at least in relative terms, since the broad introduction of diesel particulate filters a decade ago”.

“Filters are in fact so good, that in certain circumstances, when the ambient air is already polluted, a diesel car will tend to extract more particles from the air than it emits”.

Cleaning the air with diesel engines: nonsense?'make or break' for diesel in 2020

To test the theory, it worked with Auto Motor und Sport using four recent diesel models. Going to the extreme, they opened canisters of high intensity particles in front of the air intake on the cars as they idled for an hour. Particle concentration at the front soared from the 11,000 cm3 or-so ambient, to over 100,000 cm3. 

In contrast, the particle concentration measured at the rear, near the exhaust, remained flat, even dropping to around 10,000 cm3 towards the end.

Diesel use down for the first time in a decade

Then they moved to more realistic on-road testing for the four vehicles. Exhaust particles were measured from cold, neutral warm idle, under heavy load, and during DPF regeneration.

As best as possible, the typical operating conditions of a car day-to-day were simulated. Long distance, middle distance and short drives, with a mixture of cold and warm engine states, idling, heavy loads, regeneration conditions, etc.

The results were as follows:

  • Idle: 10,246 cm3
  • Warm engine: 15,803 cm3
  • Cold start: 9,114 cm3
  • Heavy load: 16,894 cm3
  • Filter regeneration: 155,555 cm3

Denmark wants 2030 ban on petrol and diesel cars

The standout result that Emissions Analytics cites, which it says it didn’t expect, is that the net addition of the car’s pollution is mostly dependent on the ambient air pollution. This reflects the way the car breathes air in, as well as the way it exhausts waste.

The overall results are staggering, with just two out of the six conditions showing emissions from the car being dirtier than the air the car is driving through. These were long distance and middle distance, in ‘clean air’ with an ambient of 10,000 cm3.

The ‘dirty air’ baseline was around 50,000 cm3. Over long distances, the cars removed around 27,984 cm3 from the dirty air. Over middle distances, they removed around 8,025 cm3 from the dirty air. On short drives, they removed around 40,886 cm3 from the dirty air.

Diesel car fuel filler

Even in clean air, as above at 10,000 cm3, a short drive removed 886 cm3 from the ambient air. Long distance and middle distance did, however, add 2,000 cm3 and 21,000 cm3 respectively.

Emissions Analytics clarifies, that it would be a broad stroke to say that diesel engines clean the air. This is purely a measurement of particulates, and ignores nitrogen oxides and other gaseous emissions. 

It’s also worth considering that many diesels still on the road are pre-DPF models. The results, nonetheless, remain food for thought.

UK diesel use in decline for the first time in a decade

Diesel use down for the first time in a decade

The ‘decline of diesel’ often refers to diesel car sales. Now, the amount the UK has burned in its vehicles is down, for the first time in a decade.

The amount burned was down by just under 500 million litres between January and November 2019. That’s 27.416 billion litres burned last year, compared with 27.909 billion litres burned in the same period in 2018.

After ten years of increasing demand, last year’s figure is lower than 2016’s. For reference, 500 million litres is roughly what the country’s diesel vehicles consume within a week.

'make or break' for diesel in 2020

It’s the first time that the use of diesel has dropped since the financial crisis over a decade ago. Is it because there are fewer diesel-powered cars on the road?

According to the AA, not entirely. The drop-off of oil burners in the new car market has had something to do with it. However, it’s also claimed that a fall in lorry and van traffic last year, as a result of economic uncertainty, will have contributed.

The drop is actually not as dramatic as some might have expected, given the scale of the scandal around diesel and the drop in appeal the fuel has suffered since it broke cover in 2015. However, as the popularity of SUVs, which are mostly diesel-powered, has ballooned, the losses have been cushioned somewhat.

Drivers oppose diesel ban

“The first drop in UK diesel demand in a decade is one to watch,” said Luke Bosdet, from the AA.

“Whether a Brexit economic bounce back reinvigorates commercial traffic levels and therefore diesel use, or whether the reduction signals UK fossil fuel use moving from tipping point to actual decline.”

84 percent of drivers oppose city diesel bans

Drivers oppose diesel ban

More than 80 percent of motorists say they oppose plans to ban diesel cars in city centres.

The poll of 989 drivers by Motorpoint found a large majority are against excluding older diesel cars from urban areas.

The news comes as Bristol City Council looks to ban all privately-owned diesel vehicles. A 1.26 square mile area of the city centre will be diesel-free between 7am and 3pm from 2021. The move is part of the government’s plan to improve air quality in 24 large urban areas by 2025.

A wider Low-Emissions Zone (LEZ) will be in effect for commercial vehicles, with a charge payable by those who enter. Taxis and vans will be charged £9, while buses and HGVs will be expected to pay £100.

Drivers oppose diesel ban

“We applaud efforts by local authorities to create ‘Clean Air Zones’ in our towns and cities,” said Mark Carpenter, CEO of Motorpoint.

“But the message from motorists is that a blanket ban on privately-owned diesels, especially when two out of five vehicles on the road today are diesels, won’t work and local authorities need to go back to the drawing board in order to come up with a solution that doesn’t just penalise diesel drivers.”

The Bristol ban is more extreme than the existing London Ultra-Low Emissions Zone (ULEZ). The latter came into effect in April of this year and all vehicles are permitted, but petrol and diesel cars that pre-date various emissions standards are liable for a charge.

The ULEZ charge in combination with the existing Congestion Charge costs drivers of such cars £24 a day. The ULEZ applies 24 hours a day, 365 days of the year.

Why 2020 will be ‘make or break’ year for diesel

'make or break' for diesel in 2020

Diesel’s difficult journey over the last few years may be about to come to a head, with some claiming 2020 will be ‘make or break’ for the under-fire fuel.

There are a number of challenges facing diesel cars, including outright bans in certain urban areas.

However, the question of whether modern ‘clean’ diesels are being treated fairly remains. Will the ongoing PR war against it kill them off regardless?

'make or break' for diesel in 2020

“We seem to have arrived at a point in time where, in terms of public perception, any nuance surrounding the diesel debate has disappeared almost completely,” said Peter Golding, managing director at FleetCheck.

“Probably the best example of this is the blanket diesel ban that is going to be applied in Bristol city centre. Older petrol cars that probably have markedly worse emissions than the latest RDE2 diesels will be allowed in.

“It makes little sense and helps to create the impression that whatever technological advances are now made with diesel, its ongoing demonisation might be inevitable.”

Make or break'make or break' for diesel in 2020

RDE2 engine standards are, Golding claims, forcing diesel engines to reach emissions standards on an even footing with petrol engines, but with the CO2 benefits that diesel has always had. With this in mind, there is now the question of whether the ongoing assault on diesel is misguided.

“In a sense, the next 12 months could prove to be something of a make-or-break period for diesel. If its reputation doesn’t make something of a recovery with the new technology coming online, then it may never do so.”

Diesel demise could increase emissionsBristol diesel car ban 2021

Traditionally, diesel engines were promoted over petrol to reduce CO2 emissions, which are related to climate change. The modern issue with diesel is nitrogen oxide (NOx), which relates to air quality. There is worry that the recent exodus to petrol could exacerbate the CO2 issue, especially in combination with the rise in popularity of heavy SUVs.

“One of the reasons that we are in the current position is because legislators long concentrated on CO2 emissions to the detriment of other environmental measures. Obsessing over diesel risks taking a similarly narrow view with similar results,” continued Golding.

“Air quality is obviously a major concern and ensuring that sensible measures are taken that make sense and bring about real change is too important not to be taken seriously. That means taking a wider view on environmental matters.”

Extinction Rebellion uses dirty diesel for climate change protest

Extinction Rebellion fire engine

Turning up to protest about climate change in a dirty diesel is a little like going to thrash metal concert and complaining about the noise.

But as Extinction Rebellion arrived in Whitehall in a 21-year-old fire truck to paint the town red, it became abundantly clear that the protesters hadn’t considered the irony of their choice of transport. After all, an 8.3-litre diesel engine is about as welcome in central London as a fox in a henhouse.

From one drama to another

It would appear that Extinction Rebellion paid £5,000 for the former Derbyshire Fire & Rescue Service Dennis Sabre back in August. Cheaper than a Dacia Sandero, then, but not as good for the planet.

It’s not the first time the fire engine has been in the public eye: the eBay ad lists an appearance on Holby City as one of its selling points. You could say it’s gone from one drama to another.

The old Dennis diesel sat outside Treasury smoking like a 70s snooker player as the Extinction Rebellion protestors struggled to contain their hose. It turned the protest into something that wouldn’t have looked out of place on Top Gear, as the fake blood coated the steps and pavement outside the Grade One listed building.

Forget London’s Burning, this was more like London’s Turning… Red.

Clearly, climate change is a serious business. Only a chump with rubbish hair and a penchant for walls would deny that we need to do something to reverse the damage that’s being done to our planet. We can all play a part.

But buying an 8.3-litre diesel fire engine in Northampton and then driving it into central London isn’t going to save the world.

With a strong wind behind it and a clear road ahead, the Dennis Sabre could probably muster 8, maybe 9 miles per gallon. Fine if you’re putting out fires or starring alongside Tina Hobley, but not so great when you’re protesting against “the vast sums [the government] pours into fossil fuel exploration”.

Maybe they should have used a Green Goddess…

Nissan slammed by DVSA for failing to fix Qashqai diesel

Nissan criticised over dirty diesel response

Nissan has come under fire from the Driver and Vehicle Standards Agency (DVSA) for its reluctance to tackle excessive exhaust emissions from Qashqai dCi diesel models.

Nitrogen oxide (NOX) emissions were found to be well above what prior testing had established in new WLTP tests – and beyond acceptable standards.

The WLTP fuel economy test was introduced last year and includes RDE (Real Driving Emissions) measurements. It replaces the old NEDC test, which was less realistic in ‘real world’ driving.

Nissan criticised over dirty diesel response

The DVSA’s findings have so far failed to prompt any action from Nissan. It says the Qashqai meets all current standards, and that its priority is future product – rather than re-calibration of existing diesel vehicles.

“All Nissan vehicles fully comply with today’s emissions legislation,” the company’s response reads. “We support the new RDE tests that have now been adopted and have introduced a range of drivetrains to meet them.

“We will continue to develop affordable and innovative solutions to reduce our impact on the environment, such as our Nissan Leaf and e-NV200 electric vehicles.”

Nissan criticised over dirty diesel response

Nissan’s sister company, Renault, has taken a more pro-active approach – something the DVSA highlights in its latest Vehicle Market Surveillance Unit report. Renault, which uses the same engine, has ‘issued a voluntary offer to customers visiting a Renault dealer to implement a NOx upgrade’.

The kicker is that if Renault offers it, then a diesel fix exists that could pertain to affected Nissan models.

The Nissan Qashqai is built at the marque’s Sunderland plant in the UK. It has been one of the UK’s best-selling cars for more than a decade.


European Court ruling could all but kill diesel in the EU next year

Diesel NOx EU

The sales of millions of diesel-powered cars could be disrupted next year, as their sale could be rendered illegal after February 2020.

It’s all thanks to a ruling by the European Court of Justice to bring forward mandatory compliance with hard 80 mg/km nitrogen oxide emissions limits under new ‘real world’ test conditions.

It was agreed in 2016 that manufacturers would have until 2023 to get automotive emissions down to such a standard, however, the European Court of Justice ruled that the measure had been incorrectly adopted and that a grace period of one year from now was appropriate.

The long and the short of it is that as many as 7.5 million cars due to be built, will be illegal to sell as of February next year.

Secretary-General of the European Automobile Manufacturers Association Erik Jonnaert warned that the impact on the industry “could indeed be enormous”, in an interview with the Financial Times.

Failing a successful appeal by the European Commission for the new deadline to not be upheld, a comprehensive re-engineering of many different diesel engines and models would have to take place. Given the time allotted, that seems unlikely, and that’s if re-engineering is enough to get them below the threshold.


Diesel NOx EU

Environmental groups continue to criticise the European motor industry for flouting legislation and cheating tests years ago and that they should have thought about the problems they’d face if caught.

That’s all well and good, but those responsible have been held accountable. To then threaten to gut the industry with a legislative knife and say ‘you should have thought about that’ is at best reductive and at worst, blissfully ignorant of the potential economic perils. The ripple effects in respective businesses are difficult to predict but are potentially severe.

On the other hand, as per a story we published earlier, should these limits inspire as much fear in manufacturers as they do? ADAC testing has proven that a selection of the very latest Euro6-d emissions standard cars are falling well below the 80mg/km NOx limits in the real world.

That is in spite, for the moment at least, of only needing to do so in lab conditions. These cars are ready-made for the worst case scenario, come February 2020.

All that said, such a change can’t not have some sort of detrimental effect. Whether it will be as severe as the Commission and these manufacturers say it will, remains to be seen. As ever these days, the industry remains stuck between a rock and a hard place.

Searches for used diesels at a record low

Diesel searches down autotrader

Searches for diesel cars are at an all-time low of 45 percent on Auto Trader, new data reveals. Meanwhile, searches for petrol-powered models are on the up, soaring to 48 percent.

Diesel – searches down, sales steady, values up

In spite of the low search numbers, prior sales figures remain strong. Used diesel sales actually increased by 0.3 percent over the course of 2018.

As for values, the rate of growth for used diesel values actually accelerated, up from 2.6 percent in January 2018 to 4.5 percent in January 2019. That leaves the average value of diesel cars at £14,514.

That doesn’t necessarily reflect any heightened appeal or value of diesel itself, perhaps rather the heightened value of a market flooded with younger and younger second-hand cars. 

Petrol and alternative fuel vehicles

Prices for petrol vehicles, in contrast to the diesel jump, actually eased. January 2018 saw petrol car prices grow 10.7 percent, while the same period this year saw just a 3.7 percent growth, to an average of £11,374.

Still, people are more curious about petrol than ever before. As above, searches are at a record high of 48 percent.

plug-in and self-charging hybrids

Alternative fuel vehicles (hybrids, electric cars) had an incredible increase in sales according to industry results, with an increase of 26.9 percent in 2018.

However, prices were, similar to petrol, staggered. January 2018’s AFV price growth was 8.4 percent, while January 2019’s was 4.6 percent, with an average price of £21,399.

Overall, the values of second-hand cars are up 4.1 percent on this time last year, to £13,025. Based on PCP run-off continuing to permeate the market, that ought only to increase.

In reality, searchers are less specific about what they want to fuel their cars than ever before.

“Fuel represents just one in five searches on our marketplace, so whilst the sustained decline in diesel is significant, it’s not representative of all consumers,” said Karolina Edwards-Smajda, Auto Trader’s commercial product director.

“Rather, with the percentage of fuel searches declining from 25 percent to 20 percent in just 18 months, it highlights that car buyers are becoming increasingly agnostic. Our research consistently shows that they’re not limiting their search to a type, but instead considering all as part of their next car journey; new, used, petrol, diesel, or electric. Retailers should be marketing to them accordingly.”

U-turn by EU lawmakers could mean a total ban on diesel cars

diesel European Commission

The European Commission and the General Court of the European Union have been locked in battle over diesel car emissions. And the Commission has lost the case, meaning certain European cities can elect to ban all diesel-powered cars. Yes, even modern diesels.

In summary, the Commission gave the nod to amend the latest Euro 6 diesel emissions limits – permitting higher nitrogen oxide limits – in response to new ‘real-world’ fuel economy tests. Put simply, they gave permission for diesels to be dirtier. The argument was that new tests would likely expose alarming figures anyway.

Where this becomes (apparently) illegal is that there was no alignment on the decision, be it with the General Court of the European Union, other senior regulatory bodies, or the public. As such, acting on behalf of city authorities such as Paris, Brussels and Madrid, the Court has held the Commission accountable for the unsanctioned amendment. 

A bit of background on the Euro 6 emissions regulations is needed, we think. They dictate that any car registered after September 2015 must not emit more than 80 mg/km of nitrogen oxides (NOx).

diesel European Commission

In defence of the car manufacturers, that target was set with reference to the testing procedures at the time. In the comparison between old (NEDC) and new (WLTP) testing methods, for instance, we know the latter is more representative of real-world driving. 

Unfortunately, more realistic testing means lower efficiency ratings and much higher emissions. That’s where the amendment comes in, sanctioned by the European Commission without further consultation, which stated cars could pass these new tests as long as emitted less than 168 milligrams per kilometre of NOx. 

The court has given the European Commission a year to set things straight, which will, in turn, give carmakers a year to revise their offerings.

diesel European Commission

Our take is as follows. Diesel is fundamentally difficult to clean. This could well be the biggest nail in the coffin of oil-burners yet. Nevertheless, legislators do conveniently ignore the categorical U-turn they’ve taken in this demonisation of diesel. And not two decades after it was lauded as the saviour of eco- and money-conscious motorists alike. Industry and technology simply cannot make overnight U-turns in response to unfavourable PR, as politicians can.

Coming back to the difficulty of engineering ‘clean’ diesels, our fear is that it’s simply not possible. Even with the thickest ad-blue concoction and the brawniest catalytic converters carmakers can muster. We hope we’re wrong.

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Fuel prices

A fuel price war could be coming, as oil costs slump

Fuel prices

Fuel prices have hit highs not seen since 2014, but the AA says relief is on the way. Relief, it says, that could amount to 3p a litre – or £1.50 a tank.

Of course, there’s always a possibility that any savings consumers can look forward to may be dented by the rumoured un-freezing of fuel duty in the Autumn budget. It’s been held at 58p a litre since 2011.

Nevertheless, the AA predicts a forthcoming decrease in prices due to the strengthening of the pound, allied with a cut in the wholesale cost of oil. Such drops have triggered penny-by-penny falls in competing forecourts’ prices in the past, resulting in price wars at the pumps.

How to find the cheapest petrol and diesel near you

“In the past, such a significant drop in wholesale prices would have triggered a pump-price battle among the supermarkets” said the AA’s fuel price spokesman, Luke Bordet.

“For the moment, drivers should keep an eye out for competitive oil company sites, taking the opportunity to undercut expensive supermarket sites”.

A drop in fuel prices would follow a full 11 consecutive weeks of price rises to date. In that time, the national average for a litre of petrol has reached £1.31 a litre. Diesel is even more expensive, at £1.35 a litre on average. Contrast to July 2018, when the average cost for petrol and diesel was £1.28 and £1.31 respectively.

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