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Has the High Court killed diesel cars in the UK?

Government air quality plans described by as "woefully inadequate"

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This week’s high court ruling that the government’s air pollution policies are inadequate and need to be improved could have major ramifications for the UK automotive landscape, especially surrounding the use of diesel fuel in our cars, vans and trucks.

Environmental group ClientEarth won its High Court battle with the Department for Environment, Food and Rural Affairs (DEFRA) over levels of air pollution. It is the second time ClientEarth has defeated the government in court over air quality, with a separate Supreme Court ruling in its favour in April 2015.

In the latest ruling, the High Court said that the 2015 Air Quality Plan failed to comply with the previous Supreme Court judgment and EU directives on air pollution. DEFRA told the BBC that it accepted the court’s judgment.

The ruling means that the government will have to go back to the drawing board on its plans to improve air quality, which are claimed to contribute to as many as 40,000 early deaths each year. Given that the government’s plan was described in the ruling as “woefully inadequate”, it seems obvious that drastic action will need to be taken.

Inevitably, this will mean a renewed assault on the automotive industry and the likely target will be diesel vehicles. Environmental groups have been pushing for diesel cars to be further taxed or even banned from cities for some time, and these calls are only going to get louder as DEFRA considers its options.

Expect a range of carrots and sticks

The Mayor of London has already openly talked about bringing forward the planned introduction of London’s Ultra Low Emissions Zone (ULEZ) to 2019, which will penalise diesel cars older than approximately 2008 and diesel heavy vehicles (buses and trucks) older than even a few years. The plan has been to charge these vehicles a daily fee to enter the London ULEZ, but it is entirely possible that the measures to stop these vehicles could become more severe. This may mean a much heftier fee, or even a total ban. It may also lead to the zone area being widened to cover larger areas of the greater London area.

London low emission zone bans older diesel trucks
The Low Emission Zone (LEZ) has already been in effect for several years. Image (c) Transport for London.

Other large cities are also likely to get their own ULEZs. This had previously been expected to roll out sometime in the next decade, but it is likely that these plans will be accelerated from theory to reality much sooner.

The requirement to toughen up air quality measures may also give the government an excuse to revisit road tax, fuel levies, company car taxation rates and other financial means to dissuade Britons from buying new or used diesel cars (and possibly petrol cars as well). One of the first casualties will almost certainly be the freeze on fuel duty which has been in place for several years; expect duty to increase in the next Budget and keep on going up.

There may well be a move to introduce a new scrappage scheme for older diesel cars which do not meet latest emissions standards. Certainly, any moves to increase taxes on diesel fuel will devalue used diesel car prices, which may naturally hasten older diesel cars towards the scrapheap without a need for the government to buy them up and scrap them.

On the flipside, it is likely that the government will have to significantly improve its efforts to support alternative automotive fuel sources. This is potentially good news for the Plug-In Car Grant, which currently gives buyers of new electric cars up to £4,500 rebate, as well as increased funding for charging infrastructure. The same could potentially apply to hydrogen fuel cell infrastructure, which is currently nearly non-existent and will need to increase dramatically before fuel cell vehicle sales can take a significant step.

Renault ZOE charging at a public charging point in London

Manufacturers of battery electric vehicles, hybrid vehicles and fuel cell vehicles will all be hoping that a combination of incentives for their cars and penalties for diesel cars will help boost their sales.

Why are diesel cars such a target?

Any time we burn a fossil fuel to create energy, we produce environmental emissions. And with about 40 million cars on our roads, we are burning a lot of petrol and diesel fuel every day. Even discounting the global warming issues, there has been an undeniable effect on air quality – especially in urban areas.

Diesel and petrol engines work in similar ways, but burning them produces differences. Petrol produces higher levels of CO2, which is bad for global warming. For this reason, governments in the UK and across Europe started promoting diesel in the 1990s. However, while burning diesel generates less CO2 than petrol, it produces higher levels of NOx emissions, which are directly harmful to anyone who enjoys breathing air. And as more and more diesel cars have flooded our increasingly crowded roads over the last 20 years, local air pollution has become a pressing problem.

Recent vehicle emissions standards have required complicated and expensive systems to minimise NOx emissions from diesel vehicles, but it’s not a complete solution. Plus, as we now know from Volkswagen’s ongoing ‘dieselgate’ scandal, the tests measuring emissions are cheatable, as well as being gamed by every manufacturer to produce cars which do well in lab testing but less so out in the real world. In essence, the fancy pollution control systems have had minimal impact in actually controlling pollution levels. Tougher lab testing protocols are a definite possibility, potentially even more so than the proposed European real-world tests.

The public backlash towards Volkswagen in particular, and diesel cars in general, has abated somewhat in recent months, but the long-term prediction for diesel car sales is one of continued decline. Any government attempts to manipulate taxation against diesel cars will almost certainly hasten this decline.

By comparison, electric vehicles (whether powered by a battery or a hydrogen fuel cell) do not produce emissions ‘at the tailpipe’. So swapping a million old diesel cars for a million new electric cars in a particular zone would be expected to produce a noticeable benefit to air quality in that location. Electricity for these vehicles is generated by power stations in a completely different location, so even if the station is burning coal or gas out in the countryside somewhere, it is not contributing to pollution in cities. It’s certainly not a perfect solution as it’s partially spreading pollution around the country rather than concentrating it in our cities, but it is a step towards improving air quality.

What about other vehicles?

Both light and heavy commercial vehicles are also likely to feel more of a squeeze as the government looks for targets to reduce pollution. Heavy CVs have been adopting their own Euro-VI emissions standards in recent years, which provide a dramatic reduction of local air pollution – backed up by more stringent emissions tests than those used for passenger cars. However, there are still a huge number of older trucks and buses which do not comply with the latest standards, and these vehicles are likely to suffer.

Light CVs (vans, pick-ups, etc.) have also adopted Euro-6 emissions standards this year, so are some way behind cars and trucks. According to the latest London ULEZ proposals, the vast majority of vans will not be allowed into London without paying a £12.50 daily charge in just over two years’ time.

The taxi industry is finally getting an emissions shake-up as well. It has always seemed ludicrous that the single most common vehicle throughout London is also the dirtiest, as taxis have long been exempt from the emissions requirements for passenger cars. Now, however, modernisation is finally coming to the taxi industry. From 1 January 2018, all taxis licensed for the first time must be zero-emission capable, while new diesel taxis will not be allowed in London. Of course, this means that many of the current filthy old taxis can still happily clog up our arteries until they hit their 15-year limit, but it is possible that this loophole will also be tightened up to get these pollution monsters off the streets sooner.

Immediate action requires substantial changes to status quo

The big issue with this week’s ruling is that it means the government has to start making real improvements to air quality immediately – not in 2020 or 2025. And that means working with the existing vehicle base around the country. We can’t rely on super-efficient solar-powered electric cars to save us as they won’t be here for many years. That essentially means the government is limited to working with what is available now. And that, in turn, is likely to lead to more punitive measures for diesel cars (especially vehicles older than about ten years) as well as all cars, buses, vans, trucks and motorbikes in general.

Meanwhile, of course, the government is more than happy to have an ever-increasing number of massively polluting jet airliners flying low over London and other cities all day, every day. Unfortunately, motorists have always been a softer target than the aviation industry…

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Stuart Masson
Stuart Massonhttps://www.thecarexpert.co.uk/
Stuart is the Editorial Director of our suite of sites: The Car Expert, The Van Expert and The Truck Expert. Originally from Australia, Stuart has had a passion for cars and the automotive industry for over thirty years. He spent a decade in automotive retail, and now works tirelessly to help car buyers by providing independent and impartial advice.