For many years diesel-fuelled cars were promoted as being “cleaner” and less polluting than petrol ones.
They accounted for half of all cars sold in the UK and Europe.
However, in 2015 came news of a scandalous manipulation of the data following investigations in the USA by at the International Council on Clean Transportation (ICCT).
The scandal, subsequently known as “Dieselgate” revealed that VW among others had embedded defeat devices in cars and their software detected when emissions tests were being run, activating pollution controls that were then switched off after the cars had left the testing labs.
The result, the researchers found, was that Nitrogen Oxide emissions were actually between 15 and 35 times the allowed limits, depending on the make of car and the climate/weather conditions at the time.
Suddenly, the diesel-fuelled vehicle fell out of favour and regulators acted to require cars to be tested on the road as well as in labs and to alter various regimes such as MOT testing, road tax and charges for entering low emission zones in London.
However, testing car emissions is more complex than first appears and if you still want a diesel car in preference to a petrol-fuelled one there are plenty of good reasons to still buy one, among them fuel economy and greater pulling power.
According to the website Air Quality.org : “emissions from petrol cars have been dramatically reduced by the introduction of catalytic converters, which oxidise pollutants such as CO to less harmful gases such as CO2.”
It says that even cars with catalytic convertors “still produce more CO and HC than diesel cars, although exhaust emissions of NOx and particulates are much lower than diesel cars.”
But, it says: “Diesel fuel contains no lead and emissions of the regulated pollutants (carbon monoxide, hydrocarbons and nitrogen oxides) are lower than those from petrol cars without a catalyst. However, when compared to petrol cars with a catalyst, diesels have higher emissions of NOx and much higher emissions of particulate matter.”
A new assessment published this month by Which? published this month by Which?, the consumer organisation, compares Diesel, petrol and hybrid cars on a range of measures.
While it says that on average it costs more to buy a diesel car, the outlay can be more quickly recovered, depending on the make and model and that “some diesel cars emit less NOx than the average petrol car” and that “diesel trumps its petrol counterpart for fuel economy on both the motorway and around town”.
So if a diesel car is more suited to your needs and your budget, there is really no reason not to buy one.
I usually have a number of great diesel cars available if you would like to take a look at my cars for sale.
