So just what is a Euro 6 diesel?
A super stringent exhaust emission standard for all diesel engines, which comes into force for all new vehicles sold after 1 January 2015.
It replaces Euro 5 standards that have been in force since 2011.
Diesels have it tough meeting the nitrous oxide emissions
Changes for petrol engines will be relatively minor, but diesels have a much tougher time having to reduce, not so much particulate emissions, but nitrous oxides, or ‘NOx’, because they are a significant greenhouse gas and air pollutant.
Scientists tell us this gas is four-times more damaging to the environment that CO2 and represents the fourth largest contributor to global warming gases being emitted today.
To meet the new Euro 6 standard, NOx has to be halved compared to Euro 5, setting the limit at just 80 mg/km compared to the permissible limit of 500 mg/km for vehicles of a 2000 vintage.
Euro 6 standards also place a cap on emissions of hydrocarbons and nitrous oxides on diesel engines at 170 mg/km, compared to 230mg/km with the current regulations.
The biggest challenge for manufacturers is that diesels emit much more NOx than petrol engines, so after some hefty research and development investment two main solutions have been formulated.
