The most recent diesel vehicles (Euro 6d-temp) produce ultra-fine particles for which there are no regulations yet, but also emit up to a thousand times more particles than normal during certain emission peaks, according to the independent study of the European NGO Transport & Environment.
The study, “New diesels, new problems” was published on Monday 13 January. If the results are confirmed, it would be a major blow to manufacturers, who are saying that diesels have never been as “clean” as they are now.
The particle filtration system, which is used to retain carcinogenic fine dust, has been installed in diesel vehicles for the past ten years. The system needs to regenerate about every 480 kilometres to remain effective. However, when it regenerates, the level of particles released can reach up to 1000 times the normal emission rate, resulting in the limits being exceeded.
This problem affects 45 million cars in Europe, with a total of 1.3 billion regenerations every year, according to Transport & Environment.
In Belgium, almost 2 million vehicles are affected. A regeneration usually happens when driving at a high speed, but can take place at any time, including when driving in a city. The process lasts about 15 minutes, but the polluting effects can last for about half an hour.
Laboratory tests of the two most popular diesel cars in Europe (Nissan Qashqai and Opel Astra) showed that both models met the legal limits for gaseous pollutants as well as the mass of particle matter.
However, during the regeneration phases, emissions exploded and exceeded the legal limits for particulate emissions by 32%, sometimes even up to 115%.
“Regulated particles are only part of the story. Smaller ultrafine particles are considered a greater threat. And yet they are ignored by official approval tests,” said Anna Krajinska, an expert engineer at Transport & Environment, reports RTBF. “The next Euro standard for pollutant emissions must close these loopholes and impose limits for all pollutants. The absolute goal is a standard that requires zero emissions for all vehicles on our roads,” she added.
A large proportion of particulate matter is still not measured today as only solid particles with a diameter greater than 23 nm are regulated.
During the test, all solid particles with a diameter greater than 10 nm were measured, resulting in the total number of particles emitted increasing from 11 to 184%.
The Brussels Times