Back in 1996, we reported on diesel "feeling the wrath of the environmental and health lobbies". So, how far have things progressed?

Modern civilisation revolves around crude oil.

Cars are one of the most visible uses for it, and therein lies the story of two brothers: petrol and diesel. They’re born of the same origin and differentiated by little other than the lengths of their carbon atom chains, yet diesel has a far dirtier (literally) image.

After all, it’s estimated that despite being more fuel efficient and producing less CO2, diesels cough out as much as 10 times more polluting soot particles than equivalent petrol-engined cars.

On 2 October 1996, Autocar’s Tony Lewin wrote about the uncertain future of the controversial fuel.

Health issues

“Diesel is set to become the environmental battle of the next decade,” we began. “Just as more car makers are turning to diesel power in order to meet stringent consumption targets, environmentalists and medical experts have come up with new warnings linking diesel particulate (PM) emissions with increased risk of respiratory diseases and cancer.”

In 1996, US Lung Foundation expert Mike Walshe said: “Diesel is hazardous because the small particles are drawn deep into the lungs and past the natural defence of the body" and that "evidence is emerging that new technology is making particles smaller, reducing their mass, not their number. This may make the health risks worse.”

Indeed, in 1988, diesel engine exhaust fumes had been classified as a ‘probable’ carcinogenic by the UN’s World Health Organization (WHO). In 2012, it confirmed that status, placing diesel in the same category as asbestos, arsenic and mustard gas.

At the time, Dr Christopher Portier, chairman of the group behind the research, said: “The scientific evidence was compelling and our conclusion was unanimous: diesel engine exhaust causes lung cancer in humans. Given the additional health impacts from diesel particulates, exposure to this mixture of chemicals should be reduced worldwide.”

In that year, the Institution of Occupational Safety and Health (IOSH) estimated that there were nearly 4700 cases of lung cancer, resulting in more than 4200 deaths, linked to diesel exhaust exposure in the EU.

Market share

Back in our 1996 article, Walshe said the most serious worry was “the rise in the number of diesel cars in Europe”.

Autocar explained: “Diesels already produce three times as much NOx as petrol models, yet the Euro 3 emissions regulations may result in an overall increase in NOx given off, as the diesel market share climbs.”

We reported that diesels accounted for just 10% of European new car sales in 1982, which had risen to 24% by 1996, and it was correctly estimated that this would rise to at least 30% by 1998.

In 2010, diesel became the most popular fuel choice in the UK for the first time, with a 50.6% market share. This share is dropping, probably due to the Volkswagen dieselgate scandal and greater awareness of the dangers of diesel. Diesels represented a 45.1% share in January 2017, a 4.3% drop on last year as Brits are driven to petrol.

It’s worth noting, though, that the proportion of diesel sales versus petrol at the nation's pumps is around 60% in favour of the former, due to the fuel’s use in HGVs and among drivers with longer average journeys.

NOx-reducing technology

In 1996, industry figures were still very positive about diesel, despite facing strict new emissions rules.

“In order to reduce PMs, we need at the very least a form of after-treatment which goes beyond just catalysis and into a trapping mechanism. Engines modifications alone will not be sufficient,” Walshe said.

Autocar continued: “Favourite at present is the particulate trap, which dramatically lowers the mass and number of particulates, especially the small ones.”

This technology, now employed across Europe in the form of the diesel particulate filter (DPF), was first used on a car, albeit briefly, on the 1984 Mercedes-Benz 300D sold in California, which had a ‘trap oxidiser’. However, it hit mainstream use in May 2000 with the Peugeot 607 2.2 HDi, making it Euro 4-compliant five years early. Today, although it is not legally mandated, every diesel-engined car sold in Europe has a DPF in order to help it to meet Euro 6 emissions regulations.

We continued in 1996: “Engineers are predicting a gradual convergence of diesel and petrol technologies as both move towards four valves, direct injection and exhaust after-treatment to reduce NOx output.”

Most engines today do indeed have four valves per cylinder, while most modern diesels, such as the Volkswagen Group’s TDI units, are direct injection, and DPFs are effective exhaust after-treatment. This is part of the reason why, although still hazardous, diesels are less polluting than they were 20 years ago.

Importance of CO2 emissions

Of course, there was also the issue of CO2 to contend with.

“Efficiency and low CO2 output is winning friends for the diesel in the European Commission, which appears to be switching its concerns from air quality to global warming.”

“Environmental pressure group Greenpeace is wholly opposed to diesel, pointing out that diesel’s CO2 reduction benefits are more than outweighed by the health risks it poses.”

However, Renault was hedging its bets. Then-president Louis Schweitzer said: “No one can weigh the different environmental dangers against one another. But we’re confident we could achieve our goal of 150g/km of CO2 even without diesel.”

And indeed they did: the most eco-friendly version of today’s Mégane, the 1.2 TCe, officially emits as little as 119g/km.

Time to die?

Evidently, many of the arguments that seem so pertinent today have been raging for many decades. Our 1996 assertion that diesel would be “the environmental battleground of the decade” was wrong only in that it’s an argument that has raged far longer than 2006. And 2016. And, despite all the health dangers surrounding NOx and particulate matter, despite Britain’s decreasing but still rampant pollution issues, and despite the furtherment and growing sales of alternatively fuelled vehicles, we may still be dithering in 2026.

Our Verdict

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Comments
7

23 February 2017
Doubt it, with falling sales of diesels due to people waking up and they're getting expensive, efficient petrol engines, and the success of EV's the sales of Diesel could hit same percentage as in America and Asia. Hopefully they're settle to around 20% or less in 9 years

 

Hydrogen cars just went POP

23 February 2017
For motorway journeys, diesels are fine. Apart from anything else, there are no pollution issues with motorways generally being in open land, with plenty of breeze to prevent build ups of pollutants In town it's a completely different matter, especially as DPF filters get clogged up if the car is only driving at low speed, and thus don't work properly...

23 February 2017
This article highlights the importance of getting the right balance in life, if our legislators demonise one fuel over another fuel it is more likely the result of an over aggressive lobby group rather than the science behind it. Even the scientific conclusions have to be viewed through a much wider lens which shows who is funding the research. The article also points out it's not just the numbers of various types of vehicle which are registered is important, but how much fuel is used by cars as well as HGV's, I would add trains, shipping and aircraft to this though. None of us leave a completely clean footprint in the earth we walk no matter which fuel we fill our tanks with, even those EV's have to have a fossil fuel footprint on account of how our electricity is generated. So I hope we don't fall into another divide and rule trap that our government set up for us in order to extract more tax from the motorist.

 Offence can only be taken not given- so give it back!

23 February 2017
Vehicle taxation is about to change dramatically in 2017...and it still favours CO2. So, declaring the imminent end of diesel - in this country at least - is distinctly premature. There will be some local actions against older diesels but national legislation continues at a snail's pace.

However, you can guarantee that whatever the government decides in the medium term will be in no-one's best interests other than state coffers and be mired in incompetence.


23 February 2017
I'm sorry to say it's worse than that, its corruption at the highest level. George Osborne changed the VED rates in favour of the oil & gas industry no doubt because his father is in it. This governments support for fracking should tell people not to listen to the empty words about this country leading the green revolution but to judge them on their actions. A whole raft of legislation has made it abundantly clear who's interests they are serving, from changes in the prisons & probation services ( think G4 and Teresa Mays husband) to privatisation of the NHS (think all the MP's who have shares in private health insurance), the list is endless and incase anyone here thinks I'm pro Labour it was just the same under Blair when this country aided by the controlled media went to war based on the lies about WMD, no doubt filling the coffers of the military industrial complex and those who they bribe.

 Offence can only be taken not given- so give it back!

23 February 2017
A lot of similarities noted in this story. However, in the U.S. much has been accomplished in cleaning up diesel during this time period. Clean diesel fuel - containing 97 percent less sulfur - is now the standard for both on-highway and off-highway diesel engines nationwide. Using this ultra-low sulfur diesel (ULSD) immediately cuts soot emissions from diesel vehicles and equipment by 10 percent. Reducing the sulfur content of diesel fuel is similar to removing lead from gasoline during the 1970s. Cleaner diesel fuel enables the development of a new generation of advanced engines and emission control devices that can't operate effectively with higher sulfur content in diesel fuel. Advanced diesel engine designs and emission control technologies were developed to meet strict tailpipe emissions standards for new commercial vehicles manufactured in 2007 and the stricter standard established for 2010. Thanks to the clean diesel system found on new and newer diesel commercial vehicles, it takes about 60 of today’s trucks to generate the same level of emissions as just one truck manufactured in 1988. Over the last 10 years, emissions from heavy-duty diesel trucks, buses and other vehicles have been reduced by 99 percent for nitrogen oxides (NOx) - an ozone precursor - and 98 percent for particulate emissions. A 97% reductions in sulfur . . . 99% reduction in NOx . . . 98% reduction in PM. A lot has happened in the past 20 years to clean up diesel in the U.S.

24 February 2017
"In 1996, US Lung Foundation expert Mike Walshe said: “Diesel is hazardous because the small particles are drawn deep into the lungs and past the natural defence of the body" and that "evidence is emerging that new technology is making particles smaller, reducing their mass, not their number. This may make the health risks worse.” "Indeed, in 1988, diesel engine exhaust fumes had been classified as a ‘probable’ carcinogenic by the UN’s World Health Organization (WHO). In 2012, it confirmed that status, placing diesel in the same category as asbestos, arsenic and mustard gas." Really says it all. Diesel is as dangerous as a weapon of mass destruction- mustard gas. We knew that 20 years ago. We went to war with Iraq over claims that Saddam had that gas and would use it! Also DPF, urea systems, EU5, EU6 etc are marketing nonsense. The soot particulates are still being belched out of a £60K Mercedes-Benz just as they were in the 90s. Now though due to efforts to clean the uncleanable they are smaller and more dangerous. The car companies just lied about cleaning up Diesel engines. They cannot be clean. Ever. Hopefully one day driving a diesel will be as unacceptable as drink driving. It is long past the time to ban it.

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