INNOVATION

Home > Innovation > Eco-technologies > Protecting air quality

PROTECTING AIR QUALITY

Emissions of pollutant gas have been halved in the last five years thanks to research by carmakers. A major actor in this research, Renault is continuing its work on improving air quality. One of the main thrusts of this policy is gradually equipping range vehicles with new technologies.

Working on combustion itself 

CO2, the main greenhouse gas, is emitted via combustion as soon as a vehicle is started. This is why Renault engineers are working on optimizing combustion. The objective is to increase performance while cutting consumption and emissions.

 

Renault created the low pressure EGR (Exhaust Gas Recirculation) system to reduce nitrogen oxide (NOx) emissions from combustion.

Using several injectors in the diesel burning process also optimizes combustion. This multi-injection diesel process reduces pollutant emissions and engine noise.

 

In the future, the HCCI diesel engine (Homogenous Charge Compression Ignition) and CAI gasoline engine (Controlled Auto Ignition) will emit practically no soot or NOx. The secret: reabsorbing part of the burnt gas to enable “cold” combustion.

 

Lastly, downsizing, a Renault expertise area, has a two-fold advantage. By reducing engine capacity, it cuts CO2 emissions while increasing performance.

Purifying exhaust gases 

 

Several after-treatment technologies can be used to reduce exhaust gas pollution.

 

With its micro-porous structure, the particulate filter rids exhaust gas of carbon particulate matter. It is automatically regenerated every 300 to 500 km.

 

With the catalytic converter, Renault has managed to reduce the concentration of carbon monoxide (CO) and NOx in exhaust gases by nearly 99%. Catalytic converters operate optimally when combined with a lambda sensor that measures the concentration of oxygen in exhaust gases.

 

To comply with future standards on pollutant emissions, Renault has developed the NOx trap, which further optimizes the functioning of the catalytic converter. The NOx trap was launched in France and Germany in September 2008 on private fleets of the 2.0 dCi Renault Espace.

Protecting air quality in the cabin 

For the comfort of driver and passengers, Renault optimizes cabin air quality by filtering the air immediately around the vehicle.

Cabin air quality also hinges on the materials used. For example, thoroughly sealing a vehicle eliminates any risk of exhaust gases seeping into the cabin.