Description

Exhaust emissions have always been an area of concern for the automotive industry. The problem lies in the fact that vehicles produce emissions when they burn the fuel to run the engine. Both petrol and diesel engines have a mixture of gases in their exhaust. Termed as “tail pipe emissions”, they are categorized as Criteria Air Contaminants (CAC) and Greenhouse Gases (GHG). CAC includes nitrogen oxide (NOx), sulphur oxides (SOx), Volatile Organic Matter (VOC), particulate matter (PM) and ammonia (NH3). GHG includes carbon dioxide (CO2) and methane (CH4) and nitrous oxide (N2 O), a colorless non-flammable gas which has upto 300 times the global warming potential of CO2.

NOx is formed when nitrogen and oxygen in air react at high temperatures. In general, the higher the peak flame temperature during combustion, the higher the NOx emissions. Diesel engines are considered to be more efficient than gasoline engines due to their high compression ratios. However, the downside of this performance benefit is that their peak flame temperature is higher than gasoline engines which results in higher NOx emissions as compared to gasoline engines. It is important to note that diesel was once promoted as an eco-friendly fuel by the EU, considering that diesel engines emit 60% less CO2 than a gasoline engine, recently the focus has shifted towards NOx emissions after the 2015 “Dieselgate” scandal that triggered a sense of urgency to bring tailpipe emissions to zero.
This research service titled “Technologies for NOx Emission Reduction and Control in Automobiles” discusses the current and upcoming regulatory standards and test procedures for NOx emissions from mobile sources and why vehicle manufacturers are scrambling to invest in emission control technologies in addition to pursuing ambitions in alternative drive train systems.
An overview of the different approaches adopted by automotive manufacturers to reduce engine-out emissions as well as exhaust after-treatment methods in light-duty and heavy-duty vehicles is provided with a detailed analysis of their technical drivers and challenges. The technologies are assessed based on their ability to meet standards, adoption potential, and their current state of maturity in the technology life cycle.
A listing of key stakeholders is presented along with recent innovations and patent filing trends to identify the growth opportunities for NOx emission monitoring and control technologies.