Death knell for diesels

Will the latest emission regulations suffocate the diesel industry?

Published:  06 August, 2014

By Neil Pattemore

The issue is focused on diesel engine vehicles, or to be more particular, particulate and NOx emissions.

It is quite simple -the modern diesel engine has become noticeably more desirable. This has been driven by not only significantly increased refinement, performance and economy but was often backed by governmental incentives. The emission levels were increasingly reduced to meet ever-tightening emission legislation and the public perception was that diesel engine vehicles were not just a viable alternative to petrol engines but were perceived as having cleaned up their act.

However, the true issue is becoming clearer. There has long been a suspicion that long term exposure to diesel emissions was seriously detrimental to human health, from irritation to eyes and throat, through cardiovascular problems to lung cancer. These suspicions were confirmed by the International Agency on Cancer (part of the World Health Organisation) in their June 2012 report.

Shortly afterwards, the European Agency for Air Quality report indicated that the steady improvement in air quality has stopped and is now getting worse, with rises in particulates and NOx being most noticeable. One of the key sources was considered to be diesel engine road vehicles (although to be fair, carbon from tyres and ultrafine brake dust particles are also significant sources). There was therefore a question as to how this could happen when modern diesel engines were supposed to be cleaner. The problem is about both the size and the quantity of the particulates - or more specifically, the total mass. The human eye can only see particles as small as 25 microns but the most harmful particulates are around 10 microns, which are small enough to be easily inhaled and get down into the smallest vessels of the lungs, where they lodge. When you get down to ultrafine particles of 2.5 microns or less, they are small enough to pass through the lungs into the bloodstream. It gets even worse - the most harmful toxins are attached to the particulates. I think by now you are beginning to understand the core issue - modern diesels produce ultrafine particulates which you cannot see (unless you look across a city and can see the total mass as smog) but are building up to increasingly kill the population. Anne Hidalgo, the front runner to be the next Mayor of Paris has already vowed to completely ban diesels from the city under her jurisdiction if elected.

The problem is made worse by weak roadworthiness (MOT) testing that cannot reliably identify if the diesel particulate filter (DPF) has been removed, which is particularly a city problem where the pollution levels are at the highest but where many DPFs clog and are removed, creating a vicious circle. The issue of DPF removal will only get worse as the costs of repairing Euro 5/6 emission systems impacts ageing vehicles.

Perhaps Norway is showing the way forward and has become the largest worldwide market for the all-electric Tesla S. I fully accept that even though the Tesla has outsold every other car in Norway in April to create a record monthly total, this is a country which can afford to choose this solution.

The European exhaust emission legislation for passenger cars has significantly reduced NOx and particulate mass as it has evolved from Euro 4 to Euro 5 but the latest Euro 6 legislation has only imposed a reduction on NOx. In doing so, it has further increased the costs of meeting these emission regulations. This makes diesel engine vehicles more expensive to manufacture and sell, making diesels less attractive, which in turn reduces their production volumes, further increasing costs and selling prices, so a downward spiral has begun.

So where is all this leading for you and your business? Quite simply, diesels are likely to be a substantial part of your business, or even an area that you specialise in. However, the rejection of diesel on the grounds of both their effect on air quality and the increasing price of buying them will start a downward trend which is only likely to exponentially increase.

What will replace diesels? The simple answer would be petrol engines that are smaller yet more powerful and economical, but there is also likely to be an increasing switch to hybrid or even full electric vehicles. This increasing volume, supported by the increasing infrastructure of fast charging points, has started to alleviate the initial price and 'range anxiety' issues.

Related Articles


Sign Up

For the latest news and updates from Aftermarket Magazine.


Where should the next Automechanika show be held?


©DFA Media 1999-2019