Combustion-engined passenger cars

Most modern combustion-engined passenger cars have either a petrol or diesel engine. The energy and/or fuel consumption therefore depends on both the general vehicle properties (such as weight, aerodynamics etc.) and the engine efficiency. Driving behaviour (speed, acceleration) and the place of use (town, motorway, country road) also play a significant role. Diesel engines are generally slightly more efficient than petrol engines – i.e. diesel engines usually have slightly lower fuel consumption than comparable petrol vehicles.

The CO₂ emissions from combustion-engined passenger cars depend directly on the fuel consumption. Biofuels are considered to be carbon-neutral because the CO₂ was extracted from the atmosphere during growth of the biomass. However, the agricultural production of biofuels is partly associated with significant CO₂emissions (and other environmental effects). The overall balance for biofuels must therefore be considered across the entire life cycle. All conventional fuels today contain proportions of biofuels (admixture).

Pollutant emissions from combustion-engined passenger cars depend on the engine and the whether the vehicles are fitted with an exhaust gas treatment system (particulate filters, catalytic converters). European emissions standards have led to a continual reduction in pollutant emissions from cars. However, the air quality limit values for NO₂ and particulates are still being exceeded on many busy roads. NO₂ and particulates are primarily emitted from diesel cars. The lower fuel consumption is often counteracted by higher pollutant emissions. Further improvement of passenger car exhaust emissions is therefore necessary.

Back

Details

Last Updated on Friday, 03 May 2013 20:06