Answer to Question #219890 in Civil and Environmental Engineering for Khile

Question

Explain the NOx emissions of Diesel cars. (What environmental 

problem it causes, health problems related to it, how it can be managed 

in diesel vehicles, why VW did not opt to use it, Standards set in US, 

how it is regulated) 

4. In light of the above problems, why didn’t they rather opt for hybrid or 

electric cars

Answer 1

Diesel engines operate at a higher temperature and pressure the conditions which favour the production of NOx gases.

Elevated levels of nitrogen dioxide can cause damage to the human respiratory tract and increase a person's vulnerability to, and the severity of, respiratory infections and asthma.

Long-term exposure to high levels of nitrogen dioxide can cause chronic lung disease.

It may also affect the senses, for example, by reducing a person's ability to smell an odour.

High levels of nitrogen dioxide are also harmful to vegetation—damaging foliage, decreasing growth or reducing crop yields.

Nitrogen dioxide can fade and discolour furnishings and fabrics, reduce visibility, and react with surfaces.

These emissions can be reduced by making process changes (such as modifications to the combustion process) or by installing air pollution control equipment (such as selective non-catalytic reduction (SNCR) or selective catalytic reduction (SCR)).

VW opt not to use standard set by USA regulations because they couldn't find a technical solution within the company's "time frame and budget" to build diesel engines that would meet U.S. emissions standards.