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Reducing NOx emissions from road transport

Road transport is the third largest source of UK greenhouse gases accounting for more than 20% of total emissions. Traditionally vehicle emissions have been calculated by measuring carbon dioxide emitted from a vehicle during tests. However new, more stringent tests have come into force to effectively measure other harmful emissions including NOx gases.

NOx is created in diesel engines when nitrogen from the fuel mixes with air during the combustion cycle. NOx is a major contributor to greenhouse gases as it is made up of more than one gas - it contains nitrogen oxide, nitrous oxide and nitrogen dioxide. Nitrogen dioxide is thought to account for more than 7% of all major contributors to greenhouse gases.

To combat the effects of road transport gases on the environment various European directives have been introduced. These directives are aimed at reducing ‘regulated emissions’ such as carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HCs) and particulate matter less than 10 microns in size (PM10). Recently the new Euro 6 directive was introduced for new cars and light duty vans.

From September 2017 all newly launched vehicle models are required to be tested using the Worldwide Harmonised Light Vehicle Testing Procedure (WLTP) which will replace the currently used New European Drive Cycle (NEDC) tests. In addition, from September 2019 the Real Driving Emissions (RDE) which has already been introduced, will be used to test all newly registered vehicles.

To reduce NOx emissions most diesel cars are required to use AdBlue, a solution made from water and urea that turns nitrogen oxides into harmless nitrogen and oxygen using Selective Catalytic Reduction (SCR).

Securing a regular supply of AdBlue should be high in a transport managers list of priorities as many cars will not be able to operate if the Adblue tank runs dry. With the AID Direct Supply Scheme you can rest assured that your fleet will have a consistent supply of AdBlue to keep it running smoothly.