The Netherlands Environment Agency (PBL) estimates that from now to 2050 around 100 million premature deaths linked to air pollution could be avoided through measures such as low emission cars.
The health and economic toll of poor air quality affects vulnerable residents most: the poor, children, and the elderly who live, play, walk and work on or close to congested urban highways.
Costs accrue in lost working days, increased morbidity and mortality, decreased productivity, damage to property, reduced agricultural output, and loss of tourism revenue. A recent study in Mexico showed that air pollution affects brain as well as cardio-vascular health, contributing to brain inflammation and intellectual deficits in school-age children.
Cutting vehicle fuel use per km in half will halve the rate of CO2 emissions from vehicles; the overall change in CO2 emissions will also depend on the types of fuels used, the rate of growth in vehicle ownership and annual distance driven per vehicle, and on in-use conditions that can cause vehicles to perform far below their tested efficiency rating.
Improving fuel efficiency and promoting newer, more fuel efficient cars, will also reduce other vehicular emissions that contribute to global climate change, especially N2O and black carbon. Recent studies show that black carbon is likely to be the second most important contributor (next to CO2) to global warming.
When fuel is burned in a vehicle engine, there will always be some emissions. Vehicle emissions are one of a number of contributing factors to poor urban air quality. Key emissions from vehicles include carbon monoxide (CO), unburned hydrocarbons or volatile organic compounds (HC or VOC), nitrogen oxides (NOx), and particulate matter (PM).
These emissions depend very much on the fuels used and the design of the vehicles. Estimates of motor vehicle contribution to urban air pollution worldwide vary anywhere between 25 and 75 percent, depending on the pollutant and the location.The introduction of very efficient petrol vehicles with additional emissions controls systems will contribute to emission reductions. For diesel vehicles, there has been significant progress in reducing the level of sulphur in diesel which has gone hand in hand with the introduction of cleaner diesel engines and after-treatment technologies. Further improvements, including advanced after-treatment devices such as particulate traps and catalyst-NOx controls and SCR systems, are being introduced, significantly reducing diesel vehicle emissions. The introduction of low-sulphur diesel fuels has made the introduction of after-treatment technologies possible.