BELGIUM: New petrol engines pollute more than diesels

By Graeme Roberts | 28 November 2013

New gasoline direct injection (GDI) car petrol engines emit more cancer causing particles than modern diesel engines, a study by independent vehicle researchers TUV Nord claimed.

While GDI engines make petrol cars more fuel efficient and emit less CO2, the findings show that these engines typically release around 1,000 times more harmful particles than traditional petrol engines and 10 times more than new diesels.

"The cost of a filter to eliminate particle emissions from GDI cars is low (around EUR50), with no loss in fuel efficiency and a big societal benefit. Despite this, carmakers are delaying fitting filters on GDI cars," TUV Nord said.

Greg Archer, clean vehicles manager at Transport & Environment, said: “Cars are the largest source of air pollution in Europe’s cities and 90% of European citizens are already exposed to harmful levels of particle pollution. Carmakers’ reluctance to install cheap particle filters on GDI engines means that society as a whole has to pay the cost through more ill health.”

EU laws already require particle filters to be fitted to all new diesel cars but there is no mandatory requirement for new petrol engines. By 2020, GDI engines are expected to power almost all new petrol cars sold in Europe, accounting for around half of all new passenger vehicles.

Vehicles tested by TUV Nord all showed the number of particles emitted from GDI engines is likely to exceed the 2017 European emissions limits, Euro 6. Emissions from the Renault Mégane were almost twice as high as those from the Ford Focus and Hyundai i40, when tested without a gasoline particle filter fitted. Fitting the filter reduced the number of particles in the exhaust by a factor of around 2,000, enabling the car to emit levels of particles in similar numbers to those found in unpolluted air.

There is also widespread concern that, as with fuel economy figures for cars, there will be a large disparity between particle emissions in vehicle tests and the actual emissions from real-world driving. With a filter fitted the emissions are negligible under all driving conditions.

“More fuel-efficient, lower CO2 GDI engines would be a great innovation if they did not emit harmful particles. These particles can be eliminated for the price of a hands free kit. It’s time for carmakers to act responsibly and make petrol cars less polluting overall,” Archer said.