Based on empirical data and academic literature, vehicles of different technologies emit different amounts of pollutants. Petrol vehicles tend to produce more carbon dioxide (CO2), carbon monoxide (CO) and hydrocarbons (HC), whilst diesel vehicles are more carbon efficient, but produce more nitrogen oxides (NOx) and particulate matter (PM). The inclusion of various types of pollutants in the scheme allows for a more holistic evaluation of vehicle models and encourages the purchase of cleaner car and taxi models that not only emit lower levels of CO2, but also lower levels of other pollutants in order to further improve our ambient air quality.
The 5 pollutants were selected and based on our existing type approval emissions standards for new vehicles. Under the VES, the emission standards include pollutants such as HC, CO, NOx, PM and CO2.
The VES rebate or surcharge will be determined by the worst performing pollutant. The National Environment Agency (NEA) requires all new vehicles to be tested for their emissions. Only those that passed the emissions standards can be registered. These pollutants are also proven by scientific studies to have adverse impact to human health.